Advances in digital dentistry have greatly enhanced what dentists can do for their patients in the clinical setting by increasing efficiency and ensuring more predictable, favorable clinical outcomes. For example, the use of computer-aided design/computer-aided manufacturing (CAD/CAM) systems in dentistry, such as Dentsply Sirona’s CEREC CAD/CAM system for same-day single-tooth restoration, has increased dramatically during the last decade. Our office started moving in the digital direction in 2014 when we began using CEREC for single-tooth, fixed restorations.

More recently, we have stepped outside of using in-office systems just for single-tooth restorations and have begun using our scanners to work collaboratively with dental laboratories for more complex cases. We have gradually transitioned our removable restorations in that direction as a result of Primescan’s (Dentsply Sirona) capability to scan full arches accurately. Incorporating digital technology has made dental outcomes more predictable and has improved our patients’ experiences in many ways.

The transition for any patient from having teeth to having no teeth is a profound transformation that has physical and emotional ramifications. The most predictable way to prosthetically mimic Mother Nature is to place multiple implants and fabricate a fixed denture to achieve function, form, and aesthetics. For this particular multidisciplinary case, we partnered with dental lab technician Paolo Lubrano from Bespoke Dental Technologies (Milford, Conn) and an oral surgeon who could provide general sedation at a surgical center. Even with the advent of modern technology to assist in collaborating and coordinating treatment more easily over live video calls, it was important to choose a lab in close proximity to the practice. Due to the nature of the complex treatment that would necessitate conversion of a denture chairside on the day of surgery, I felt it was crucial for the best clinical outcome. The ability to have in-person meetings and for the patient to meet the lab technician, which would instill trust in the process, was paramount to the overall success of the case. We needed a lab technician who was able to attend, assist, and again convert the immediate dentures chairside on the day of surgery. This was the most complex and extensive case we have partnered on with a dental lab to date, and the results were exceptional.

CASE REPORT

In 2019, a 55-year-old male presented with multiple failing restorations, partial edentulism, multiple areas of decay, failing root canals, and periodontal disease (Figure 1). The patient not only desired a new smile but, more importantly, he also wanted to be able to function by being able to eat and chew comfortably. The patient was given an ideal treatment plan, alternative treatment options, and the range of fees associated with the respective options. He was also advised to do some reading and research on his own and to even seek another professional opinion due to the extensive, life-changing nature of the treatment and the substantial financial investment he would be making.

Figure 1. The patient presented with mul- tiple failing restorations, areas of decay, partial edentulism, failing root canals, and periodontal disease.

The patient was absent from the practice during the pandemic but returned in November 2022. At that time, he had already had a consultation with the oral and maxillofacial surgeon, Dr. David Solomon, and decided he would require sedation for the surgical phase of treatment. The treatment plan included placing 6 implants in each arch to support 2 full-arch zirconia prostheses.

Following the Xcell Implant Process, a technique developed by Dr. Jonathan Abenaim, the patient’s hard and soft tissues were digitally scanned with the Primescan. The scans, along with one fully retracted, full-face digital photograph and one full-face smiling digital photograph, were sent to the lab along with the preferred shade for the immediate dentures that would be 3D printed. Dentures would be printed preoperatively to be used as immediate dentures by the patient starting the day of the surgical extractions and implant placement.

In preparation for designing and printing the temporary full dentures, the images were superimposed into the 3Shape design software. This process enabled the lab technician to correct everything from the necessity of shifting or uprighting the midline to even leveling a natural cant, which was apparent when the patient smiled. The 2 full-face photos taken pre-op would be superimposed with the digital scan, enabling this process to occur easily and predictably.

After designing the temporary prosthesis (Figure 2), the STL file was exported on the Asiga composer, and prototypes for the upper and lower dentures were 3D printed on the Asiga Max using Rodin Titan (Pac-Dent) (Figures 3 to 5). The printing process for both arches took approximately 50 minutes. The same file was also printed in Keystone HardClear (Keystone Industries) with the occlusal of all teeth cut out, which would function as a surgical template. This would provide the surgeon with a guide for the hard-tissue boundaries where the implants could be placed.

Figure 2. To ensure proper fit of the Rodin Titan (Pac-Dent) protype hybrid, the pro- totype of the hybrid was nested with the intaglio on the Asiga composer to design the prosthesis.

Figure 3. Rodin Titan temporaries 3D printed with the Asiga Max.

Figure 4. The hybrid temporaries were processed and cured.

Figure 5. The Rodin Titan.

The Asiga Max features a smart positioning system that has a series of positioning encoders that read the precise position of the build platform during layering to ensure that each layer is formed accurately. It also has a high-power UV 385-nm LED, which cures faster at deeper UV wavelengths, helping to reduce overcure. It is an “open material” system, which means a wide variety of manufacturers’ materials (more than 400) can be used with it for 3D printing. Additionally, the touchscreen display is very user-friendly.

Choosing a Resin for the Temporaries 

We chose Rodin 3D Resin (Pac-Dent) printing materials, which are FDA-registered, biocompatible medical devices. Rodin Titan (Figure 5) is a unique ceramic nanohybrid resin engineered to be used for full-arch restorations and provisional hybrid dentures. It shares the core composition of Rodin Sculpture, which is a newer class II ceramic nanohybrid with analogous ceramic filler content. Rodin Titan possesses a substantial increase in flexibility for greater impact strength. The increased flexural modulus is ideal for printing full-arch restorations such as split-file designs, full monolithic dentures, and immediate screw-retained dentures.

Titan’s formulation allows quick and accurate 3D printing and is available in 6 VITA shades (0M1, 0M3, B1, A1, A2, and A3) to enable the replication of natural aesthetics, including translucency and radiopacity. Restorations can be customized with acrylic-based, light-curable stain and glaze systems, like the Rodin Palette Naturalizing Kit (Pac-Dent).

Every resin formulated for 3D printing has a specific method for post-processing. Rodin is unique because it is rinsed for just a second in isopropyl alcohol. A spray bottle containing isopropyl alcohol was used to lightly spritz the prototypes. After air drying, they were sprayed a second time and allowed to air dry again. The next step was to light cure them in an Otoflash G171 Curing Light with nitrogen gas for a 4,500 total flash output. According to the manufacturer, the Otoflash UV is a little stronger than that of other light-curing boxes. 

Next, the prototype was glazed (OPTIGLAZE Color [GC]), which was set by undergoing 200 flashes under nitrogen in the Otoflash. The temporary was then characterized by staining and glazing to achieve as natural a look as possible (Figure 6). Generally, this involves applying a clear coat of glaze followed by adding a little brown for character, blue for translucency, and perhaps some white. The prototype was then light-cured again for 200 flashes as a final set for the glaze (Figure 7).

Figure 6. (a and b) The hybrids after staining and glazing with Rodin Palette (Pac-Dent).

Figure 7. (a and b) Occlusal view of finished temporaries.

Day of Surgery

With the restorative dentist and lab technician present, the oral and maxillofacial surgeon removed the patient’s remaining teeth under general anesthesia in a surgical center. Twelve Biomet 3i platform-switching implants (5/4 and 4/3), 6 in each jaw, were immediately placed referencing the free-hand guide created in the lab. Multi-unit abutments (MUA) were placed on the implants on the day of surgery for ease in restoring the case. This helps the tissue to heal and adapt around the MUA and eliminates the need for a more involved, subsequent “uncovery” appointment, which may include the potential need to cut the tissue.

When the patient awoke from sedation, 2 temporary immediate dentures were ready to be converted into hybrids and fixed in the mouth (Figures 8 to 12). The patient was thoroughly instructed pre- and postoperatively to adhere to a liquid and soft diet until the implants were fully integrated, typically for a period of 4 to 6 months.

Figure 8. The temporary hybrid on the day of insertion and after healing.

Figure 9. Profile with the temporary hybrid on the day of insertion.

Figures 10 to 12. Retracted view of the temporary hybrid in place.

Final Scans

When integration was complete, the converted dentures were removed, the MUA healing caps were removed, and JA scan bodies (Dr. Jonathan Abenaim—Xcell Implant Process) were placed. Digital scans of the upper and lower arches were then taken using the Primescan.

The JA scan bodies are made of titanium and have a simplified geometry and size. They were designed to enable scanning the full arch quickly and accurately with any intraoral scanner. They were also designed to be used as healing abutments. These scan bodies were left on the MUAs during this short period of time, and the dentures were relined with a soft reline material (GC Reline II [GC]) so that the JA scan bodies could be captured. This allows for less chair time, less retrieval of components in and out of the mouth, and better retention of the temporary denture. These scan bodies could have even been placed on the MUAs at the time of surgery and scanned on the day of surgery. Still, in this particular case, this workflow was not utilized due to the nature of the surgery being completed under sedation in a surgical center.

The scans were sent to the lab, where the scan bodies were aligned using 3shape software, and the final prosthesis was designed. At this stage, the bite, midlines, mold form, size and shape of the teeth, and the natural-looking aesthetics of the teeth were incorporated into the design. This is a crucial difference in the workflow that is a game changer for the clinician with regard to chair time and cost. We are now able to print implant-retained temporary prostheses using temporary materials.

For this patient, the temporaries were 3D printed using Rodin Titan in the Asiga Max printer and glazed using Rodin Palette. At this point, PMMA temporaries of the maxillary and mandibular full-arch prostheses were printed in less than an hour per arch. This temporary does not have any Ti-bases and can be completed very easily and cost-effectively. We are able to allow the patients to wear these temporaries for periods of time to work out their function, parafunction, form, and phonetics, as well as to confirm their aesthetics. We can very easily scan any changes, such as wear patterns that have been established over time or adjustments to the length of anterior teeth made by the clinician chairside in the temporaries, and remake a new set if the clinician and/or patient desires. Any changes can then be confidently converted to zirconia in the final prosthesis.

Choosing the Screw-Retention System

We chose the Powerball screw and its corresponding scan bodies system for the various reasons mentioned above. One of the main advantages is that it can be used to fabricate Ti-base-less prostheses. This means that the MUA can be connected directly without the use of a titanium base. It is the first patented screw designed for full-arch zirconia/PMMA/resin prostheses.

Historically, the issue with the design of traditional zirconia prostheses has been that they have not been able to connect directly to the implants without using a Ti-base. The prostheses were implant-level fixtures, and connecting the prosthesis directly to the implant could only be accomplished with a Ti-base. With the Powerball screw process, the MUAs are put on the implants, and the prosthesis is connected directly to them. Then the Powerball screw connects directly into the MUA, eliminating the Ti-base.

Not having a Ti-base on the prosthesis means less restorative space is needed. This, in turn, means that a stronger prosthesis is fabricated, and the fear of a debond of a Ti-base from the prosthesis and/or fracture of the Ti-base or the zirconia is eliminated. In addition, the edges of the screw are rounded to allow easy milling and the correct union of the screw and the corresponding prosthesis. Facial screw access is no longer a reality, as the screw allows for up to a 30° angle correction. Another advantage of the system is that the head of the screw uses a proprietary screwdriver that allows torque to be achieved without causing stripping of the head.

Another favorable aspect of this change in protocol is that it is less catastrophic if an issue requires removing the prosthesis. For instance, if a Ti-base debonds, the prosthesis must be removed and recemented chairside, and that is if the prosthesis did not break. If a screw fractures, it would be within the implant, whereas if a screw fractures in this system, it would be in the MUA, which can be removed more easily while preserving the prosthesis. Another drawback to Ti-bases is that if excess cement is left around a Ti-base, it could lead to peri-implantitis.

For these reasons, this is a more patient-friendly system. Parts can be replaced more easily and in less time, and patients will not be without their prostheses for days while dental labs remake them. This system saves both clinicians and patients a significant amount of time and money.

After the prototypes were inserted, the bite was equilibrated chairside, and some minor design concerns were addressed. A second set of temporary prostheses was in place for 2 weeks, and then wear and chewing patterns were checked. Those were scanned, superimposed over the design in 3Shape, “bio-copied,” and adjusted for in the design of the final zirconia (ArgenZ HT+) prosthesis.

The patient was thrilled with the temporaries and even happier with the final dentures and the final aesthetic results (Figures 13 and 14).

Figure 13. Final zirconia prosthesis (ArgenZ HT+).

Figure 14. The patient with tears of joy in his eyes.

CONCLUSION

The result of following a digital workflow, specifically the Xcell Implant Process, is that it is a more predictable, cost-effective, and time-saving process that allows an advanced dental procedure to be easily accomplished by the general practitioner with proper training. The digital workflow is seamless, and the resulting accuracy will guarantee that the prosthesis fits without distortion. It has eliminated many clinical steps and appointments, including physical models; the introduction of inaccuracy by having multiple models; the use of verification jigs; and the necessity of using costly and multiple implant parts, such as cylinders and/or Ti-bases.

In addition, multiple PMMA temporaries can be fabricated easily and inexpensively until aesthetics and occlusion have been worked out to the patient’s and clinician’s satisfaction. These PMMA temps can even be fabricated chairside if the clinician has an in-house printer and the appropriate software. Resins such as Rodin Titan were used successfully and proved to have adequate strength and aesthetics for full-arch temporary prostheses.

Because of the complex nature of this case, it was important to collaborate with a local lab. It should be noted that this was Bespoke’s first digital workflow for a hybrid case and the process went as smoothly as it would have with a seasoned lab due to the simplicity of the XCell Implant Process and use of the Powerball screw.

ABOUT THE AUTHORS

Dr. You graduated from the University of Alabama at Birmingham School of Dentistry and completed a General Practice Residency at St. Francis in Hartford, Conn. She practices general dentistry and now owns a private practice in New Haven, Conn. She can be reached at dr.you@lumos.dental.

Mr. Lubrano is a master ceramist who graduated from dental school at the University of Perugia in Italy in 2010. After working in the clinical area of dentistry, Mr. Lubrano fell in love with the artistry of the lab business. His passion for ceramics and lab work grew as he learned more about implants and the digital workflow, and he has taken many courses over the past 10 years to develop his craft, which also led to involvement in guided surgery for simple and complex cases. He later became a KOL for ZimVie Dental and Asiga. He can be reached via email at p.lubrano@bespokedentallab.com. 

Disclosure: The authors report no disclosures.  

Sjögren’s Syndrome (SS) is a systemic autoimmune disease affecting the exocrine glands. It is characterized by intense lymphocytic infiltration that progressively destroys mainly salivary and lacrimal glands.^1,2 SS is subdivided into 2 categories: primary, which includes dry eyes and hyposalivation, and secondary, which occurs in conjunction with other connective-tissue diseases (eg, arthritis and lupus erythematosus, among others).³ The etiology is unknown. It is suggested that an interaction between environmental factors (eg, viruses, stress, hormones) and patient genetics can lead to inflammatory responses against epithelial tissues.^4,5 

SS is the second most common connective tissue disease, affecting up to 3.1 million Americans, or approximately 1 in 70 people, according to the National Arthritis Data Workgroup. This number refers to those presenting with primary SS. It can be doubled if including patients presenting with secondary SS.^6,7 It is more commonly found in women than in men (9:1) and is most often diagnosed during the fourth and fifth decades of life.^5,8 

Oral symptoms include dry mouth; cracked lips; angular cheilitis; mucosal sores; tongue depapillation; swelling of the salivary glands; oral infections, such as candidiasis; and difficulty in mastication, swallowing, and speech. Hyposalivation and changes in saliva composition can cause a burning sensation and an intolerance to the use of removable prostheses.⁹ Moreover, patients with xerostomia have a high incidence of caries, resulting in the extraction of teeth during their lifetimes.¹⁰ This oral agony impacts patients psychologically and emotionally, affecting their social interactions and quality of life.¹¹ 

Early interdisciplinary intervention is recommended to provide long-term solutions for improving function, speech, aesthetics, and self-esteem.

Oral rehabilitation with implants is a possible solution since SS does not affect bone healing and osseointegration.^2,5,12 Binon and Fowler¹³ presented a case report with mandibular-osseointegrated implants and a fixed prosthesis that remained functional and stable after 13 years of followup. Due to the difficulties SS patients have wearing removable prostheses, a fixed transitional prosthesis during the surgical stage is key. Drew et al¹⁴ proposed the stage approach, in which hopeless teeth are kept in strategic positions as abutments to support an interim fixed prosthesis during the surgical stage, making the transition from a terminal dentition to a full-arch reconstruction easier. Some of the advantages of this technique include increased patient comfort, soft-tissue management, protection of grafted areas, alveolar bone preservation, and surgical templates for the position of future implants.

Furthermore, the severity of caries makes the extraction of teeth a very common procedure affecting the alveolar ridge morphology. In general, the buccal vertical bone resorbed 2.2 mm after extraction, making the ridge augmentation procedure required before implant placement in most cases. Another option to avoid extraction in strategic sites is root preservation. Its requirements include prophylactic root canal therapy and removal of coronal tooth structure, leaving the root face below the crestal bone. This technique preserves the ridge form on pontic sites between teeth or implants, supports the soft tissue, and prevents epithelial down growth.¹⁵ The aim of the present case series is to show a simple way to restore these complex cases. Case 1 shows the sequence from a terminal dentition to full-mouth, implant-supported prostheses using the stage approach and the root banking technique. Case 2 shows the longevity of an SS patient after 15 years of followups using the staged approach.

CASE REPORTS

Case 1 

A 59-year-old Caucasian female presented to the department of periodontics, Rutgers School of Dental Medicine, with the chief complaint of “All my teeth are breaking.” She was diagnosed with SS and rheumatoid arthritis in 2015. The patient was dissatisfied with her smile and came to the school to find a permanent solution. Intraoral examination revealed a partially edentulous maxilla and mandible, dry mouth, and subgingival carious lesions in the majority of her teeth with a decrease in the occlusal vertical dimension (OVD) (Figure 1). Radiographic examination revealed sinus pneumatization, recurrent and subgingival caries, and defective endodontic lesions (Figures 2 and 3). On the first visit, oral health was addressed by prescribing a high-fluoride toothpaste (PreviDent 5000 [Colgate Oral Pharmaceuticals]) to be used 3 times per day. A comprehensive evaluation of her case with a multidisciplinary team, including the prosthodontics and periodontics departments, determined that a full-mouth implant rehabilitation would be the best option for her. The patient was motivated and agreed to proceed with the treatment.

Figure 1a.

Figure 1b.

Figure 1c.

Figure 1d — Figure 1. (a to c) Initial clinical view. The patient presented with severe subgingival caries and remaining roots and missing several teeth. (d) Asymmetry in her smile that does not follow the lower lip, and several missing teeth in the posterior areas.

Figure 2. Initial panoramic radiograph showing the terminal dentition and bilateral pneumatization of the maxillary sinuses.

Figure 3. Initial periapical radiographs with recurrent and subgingival caries, missing teeth, and defective endodontic lesions.

Treatment was planned to have multiple phases. The first phase involved the abutment selection to hold the interim fixed prostheses. In the maxilla, the upper right canine, central incisors, and first upper left premolar were selected, and in the mandible, the lateral incisors, lower left first molar, and lower right second premolar were selected. These teeth presented a strategic position in the arches without periodontal involvement or mobility. Preliminary casts were articulated in centric relation, and diagnostic waxing was made with OVD increased, improving aesthetics and function.

The teeth were prepared, and hopeless teeth were decoronated (their pulp chambers were calcified). Subgingival carious lesions were excavated and restored with glass ionomer material. Then polymethyl methacrylate (PMMA) shells with metal reinforcements were relined with PMMA (ALIKE [GC America]) (Figures 4 to 6).

Figures 4 and 5. Temporary abutments were prepared.

Figure 6. Maxillary and mandibular interim full-arch prostheses inserted after teeth were prepared and hopeless teeth were decoronated.

The second step involved the surgical phase. Decoronated teeth were extracted and grafted with allograft (RegenerOss [ZimVie]) and resorbable membrane (Geistlich Bio-Gide [Geistlich Pharma AG]) to maintain the bony architecture for future implant placement (Figure 7). Four months later, CBCT was taken with guide stents. Implant planning was made with Romexis planning software (Planmeca Group), and tooth-borne surgical guides were fabricated (Figure 8). Five implants (ZimVie) were placed in each arch: In the maxilla, 4/3- × 10-mm upper right first premolar, 3.25- × 13-mm and 3.25- × 11.5-mm lateral incisors, 3.25- × 11.5-mm upper left canine, and 5/4- × 10-mm second premolar; and in the mandible, 4/3- × 8.5-mm implants in the lower left second premolar and canine, 3.25- × 10-mm between central incisors, and 4/3- × 10-mm in the lower right first premolar and first molar sites (Figures 9 and 10). After surgery, interim fixed prostheses were adjusted, and pressure was released against the tissues. Implant sites were uncovered after 4 months. Then digital scans were made (TRIOS [3Shape]) with scan bodies (BellaTek Encode Impression System [ZimVie]) (Figures 11 and 12). Scans were imported into a CAD/CAM software program (3Shape Dental System [3Shape]) to fabricate a new set of interim prostheses.

Figure 7. Hopeless teeth were extracted and grafted.

Figure 8. Implant placement with a tooth-borne supported surgical guide.

Figure 9. Five implants were placed and grafted.

Figure 10. Lower anterior area, implant placement with simultaneous soft-tissue grafting with Fibro-Gide (Geistlich USA) to change the soft-tissue phenotype.

Figures 11 and 12. Scan bodies inserted to fabricate a new set of interim prostheses (implant-supported).

The third phase involved prophylactic root canal therapy in the upper right canine, central incisor, and lower lateral incisors. Root canal therapies were performed, the coronal gutta-percha was removed, and tapered preparation of the coronal canal space was made to facilitate the Geristore (DenMat) placement 2 mm below the crestal bone. A minimum of 5 mm of gutta-percha was maintained in the apical portion of the canal space to ensure an adequate apical seal. Geristore was placed in the tapered wall preparation with a small tip engaged at the level of the gutta-percha (Figure 13). The remaining teeth were decoronated, and full-arch, screw-retained prostheses were inserted, making the transition from tooth-borne interim prostheses to implant-supported interim prostheses. The upper left central incisor, second premolar, lower left first molar, and lower right second premolar were extracted and grafted with allograft (RegenerOss [ZimVie]).

Figure 13. Prophylactic root canals were performed, gutta-perchas were removed, and tapered root spaces were filled with Geristore (DenMat).

Figure 14. Smile after delivering definitive prostheses.

Figure 15. (a) Maxilla: occlusal view after cementation. (b) Mandible: occlusal view after insertion.

Figure 16. Schematic sequence, upper view: initial presentation. Lower view: selection of the strategic abutments to hold the interim prostheses.

Figure 17. Upper view: Five implants were inserted in the maxilla and in the mandible. Internal sinus elevations were made with immediate implant placement in the premolar sites. Lower view: definitive full-arch, fixed prostheses. Root banking was made to preserve the buccal anatomy and maintain the bone for possible future implants.

The fourth step involved the restorative phase, in which maxillary and mandibular master casts were generated and verified. Gold-shaded titanium custom abutments (Atlantis [Dentsply Sirona]) were inserted in the maxilla, and multi-unit abutments were placed in the mandible. PMMA prototypes were inserted and adjusted. The patient stayed with the prototypes for 2 weeks to evaluate oral hygiene, phonetics, aesthetics, and function. All the corrections were made to them. After 2 weeks, prototypes were re-scanned in the laboratory. Definitive monolithic zirconia prostheses were delivered (Figures 14 and 15). An occlusal device was inserted with 4 months of recall appointments. A treatment plan sequence was summarized in the schematic view using Dental_Flash (Attachments International) (Figures 16 and 17). 

Case 2 

A 62-year-old white female presented to the periodontics department in August 2006. Her chief complaint was that she was “tired of fillings and root canal treatments.” Previous dental treatment included several extractions, root canals, implants, and a removable partial prosthesis that she did not tolerate. She stated she had been through several reconstructions that had failed due to caries on abutment teeth. She was diagnosed with SS and Lichen Planus many years ago. Intraoral examination revealed generalized gingival inflammation with bleeding on probing, crowns and bridges in the maxilla, subgingival caries, and defective restorations in the mandible (Figure 18). Radiographic examination revealed defective restorative materials, RCTs, carious lesions, and implants on the molars and premolar areas (Figures 19 and 20). After evaluation of all her factors and patient expectations, the option of implant-supported, fixed prostheses was offered to the patient. The stage approach was crucial in her case because she had poor tolerance of a removable prosthesis in the past. A schematic sequence using Dental_Flash briefly summarized her phases using the staging approach (Figures 21 and 22). The patient has been stable for the past fifteen years with 4-month recall appointments (Figure 23).

Figure 18a.

Figure 18b.

Figure 18c — Figure 18. (a to c) Initial presentation.

Figure 19. Initial panoramic radiograph.

Figure 20. Initial periapical radiograph.

Figure 21. Upper view: initial presentation of the patient with several RCTs, subgingival caries, and defective restorations. Lower view: selection of the key abutments. Five natural abutments were preserved and connected with the poste- rior implants to stage the case. Hopeless teeth were extracted, and insertion of the fixed interim prostheses that were used during the entire treatment was done.

Figure 22. Upper view: Implants were placed as shown in the schematic. Four months after healing, abutment teeth were extracted with immediate implant placement of the lateral incisors. Lower view: The following final prostheses were planned: In the maxilla, posterior segments from first premolar to first molar; In the mandible, posterior segments from first premolar to second molar; and both anterior segments from canine to canine.

Figure 23. Fifteen-year followup: periapical radiograph of implants showing no bone loss after all those years of function.

DISCUSSION

SS patients show a high incidence of dental caries despite a recall frequency of 5 visits per year.¹⁶ One study found that SS patients with excellent oral hygiene, on 3- to 4-month recalls and fluoride dentifrices, had elevated levels of dental caries with premature tooth loss.⁷ This problem is a consequence of the decrease in salivary flow and changes in its composition.⁵ It also contributes to difficulties wearing removable prostheses because, in the absence of saliva, the protective layer is not present, making the mucosa susceptible to sores. Additionally, in a complete denture, low salivary volume can affect the retention of the prosthesis.⁹ Therefore, a different approach needs to be implemented with these patients.

The staged approach was followed to maintain a fixed interim prosthesis during the entire rehabilitation process. In 2010, Cordaro et al¹⁷ described a protocol to stage a patient. This protocol offers many benefits, such as avoiding removable prostheses, improving patient comfort, and soft-tissue management, among others.¹⁴ This technique can be performed with natural teeth or with transitional implants if natural teeth are absent.¹⁸ However, it can be more time-consuming to treatment plan, but lengthy treatment can be helpful for a patient’s financial planning.^14,17,18

Furthermore, root banking was performed to preserve the shape of the alveolar bone, gingival tissue, and alveolar mucosa. It can be done with a coronally advanced flap or an autogenous soft-tissue graft to cover over the root surfaces, allowing new cementum and connective tissue to form above the coronal surface.¹⁹ Over time, there is a flattening of the crest, and the periosteum grows on top of the maintained roots. The periosteum is attached to the supracrestal interdental fibers, and bone grows crestal to the root.²⁰ The rationale for preserving the root is to create potential future implant sites. To perform this technique, prophylactic root canal therapy with a final canal orifice restoration is needed. In 1997, the application of resin-ionomer restorative materials for the repair of external resorption defects in the cervical one-third of roots was presented. It showed high-power micrographs illustrating the close adhesion of fibroblasts and connective tissue to this dual-cure, self-adhesive resin-glass ionomer restoration.²¹ Placement of this material into the root canal space has been studied in the endodontic literature because of its ease of placement, fast setting time, and retro canal leakage qualities.²² In 2005, utilizing scanning electron microscopy, it was indicated that human gingival fibroblasts proliferate, attach, and spread when in contact with Geristore and maintain relatively normal morphology.²³

Coronal tooth structure must be maintained during the time in which root canal therapy is performed. At this stage, placement of Geristore coronal seal maintains proper restoration at the occlusal cavosurface margin seal before tooth decoronation. It is critical that the placement depth of the Geristore restoration must extend below the anticipated horizontal root sectioning on the root face. Apical gutta-percha must maintain a minimum of 5 mm apical seal length for predictable root canal therapy success. 

From the prosthodontics perspective, performing an aesthetic analysis before any intervention is paramount. In 2011, Bidra²⁴ described all the parameters that must be evaluated when a fixed, implant-supported prosthesis is in mind. Lip position and gingival display are critical and must be evaluated during static and dynamic movement when the patient smiles.²⁵ After this analysis, the possibility of adding pink ceramic to the final prosthesis was taken under consideration since after extractions and implant placement, some bone loss can cause a gingival recession that can be visible because of the amount of display of gingiva during a maximum smile. Therefore, using pink ceramic can allow adequate contours to be obtained, compensating for gingival recession and promoting aesthetics.²⁶ When pink ceramic is expected, the prosthesis-tissue junction must be evaluated. As a rule, the crestal bone level must be apical to the maxillary lip-line at the time of maximum smile. If these parameters are not met during the preoperative evaluation, an aggressive presurgical procedure must be performed before implant placement.²⁵

In addition, during the smile analysis, the necessity to restore the patient up to the first molar was evaluated. In case 1, during maximum smile, the patient showed up to the second premolars. Restoring the patient to the molar areas would have required external sinus lifts; therefore, it was decided to go with a shortened dental arch (SDA).²⁷ In a 6-year follow-up study of oral function in SDAs, the authors concluded that SDAs provide durable occlusal stability.²⁸ Likewise, Hattori et al²⁹ indicated that during maximum voluntary clenching, SDAs never caused overloading in the TMJ, and Witter³⁰ concluded that masticatory ability is generally sufficient when 20 or more teeth remain. Thus, the SDA protocol can be the most conservative treatment for high-risk patients without compromising oral functionality.²⁷

In case 2, it can be appreciated how beneficial serial extractions can be for dentists and patients. Implementing this approach, the 2-stage implant placement procedure is simple to follow. In this case, natural teeth and implants were used as strategic abutments. Because other dentists placed those implants, the case was overengineered. Early reports suggested using as many implants as possible in the maxilla, from 6 to 10, and having 4 to 8 implants in the mandible being parallel to each other to support the full-arch prostheses.³¹ Recent studies suggest that the use of 6 or more implants in the maxilla and 4 to 6 implants in the mandible results in a high survival rate above 95%.^32,33 Moreover, using the root banking technique allows us to use fewer implants, submerging roots in the pontic areas to preserve the alveolar bone for the future. Today, this case would be planned differently: 7 implants in the maxilla using the 4 implants in the posterior areas that the patient presented and adding implants for the upper right first premolar, central incisor, and upper left lateral, root banking both canines. In the mandible, recommended therapy would be to restore the case with 6 implants, including the 3 implants that patient presented with in the posterior areas and 3 additional fixtures in the bilateral cuspid areas and left second premolar area. We could also root bank bilateral first premolars and the left central incisor. In the 15-year sequential radiographs, it can be appreciated that the crestal bone around the implants remained stable, implant probing depths were 3 mm or less, and the tissues showed little change after 15 years of function. This patient maintains above average home hygiene with reinforced hygiene appointments every 4 months.

CONCLUSION

SS patients are immunocompromised with many negative impacts on their mouths, affecting their function, aesthetics, and social interactions. Thus, a multidisciplinary team is crucial to treat them. This clinical report shows how, with the use of selective terminal abutment teeth, a patient can be restored from a terminal dentition to a full-mouth, fixed rehabilitation. Since many SS patients have a history of dental failures, root banking can be a consideration to preserve the bone in the pontic sites for future implants. Fifteen years of followup indicates that the staging approach may be beneficial for the SS patient.

REFERENCES

1. de Mendonça Invernici M, Finger Stadler A, Nicolau G, et al. Management of Sjogren’s syndrome patient: a case report of prosthetic rehabilitation with 6-year follow-up. Case Rep Dent. 2014;2014:761251. doi:10.1155/2014/761251 

2. Chrcanovic BR, Kisch J, Wennerberg A. Dental implants in patients with Sjögren’s syndrome: a case series and a systematic review. Int J Oral Maxillofac Surg. 2019;48(9):1250–9. doi:10.1016/j.ijom.2019.02.005 

3. Jorkjend L, Johansson A, Johansson AK, et al. Periodontitis, caries and salivary factors in Sjögren’s syndrome patients compared to sex- and age-matched controls. J Oral Rehabil. 2003;30(4):369–78. doi:10.1046/j.1365-2842.2003.01088.x

4. Mavragani CP, Moutsopoulos HM. Sjögren’s syndrome. Annu Rev Pathol. 2014;9:273–85. doi:10.1146/annurev-pathol-012513-104728

5. González S, Sung H, Sepúlveda D, et al. Oral manifestations and their treatment in Sjögren’s syndrome. Oral Dis. 2014;20(2):153–61. doi:10.1111/odi.12105 

6. Zero DT, Brennan MT, Daniels TE, et al; Sjögren’s Syndrome Foundation Clinical Practice Guidelines Committee. Clinical practice guidelines for oral management of Sjögren disease: Dental caries prevention. J Am Dent Assoc. 2016;147(4):295-305. doi:10.1016/j.adaj.2015.11.008 

7. Cartee DL, Maker S, Dalonges D, et al. Sjögren’s syndrome: Oral manifestations and treatment, a dental perspective. J Dent Hyg. 2015;89(6):365–71.  

8. Mathews SA, Kurien BT, Scofield RH. Oral manifestations of Sjögren’s syndrome. J Dent Res. 2008;87(4):308–18. doi:10.1177/154405910808700411 

9. Bolstad AI, Skarstein K. Epidemiology of Sjögren’s syndrome—from an oral perspective. Curr Oral Health Rep. 2016;3(4):328–36. doi:10.1007/s40496-016-0112-0 

10. Christensen LB, Petersen PE, Thorn JJ, et al. Dental caries and dental health behavior of patients with primary Sjögren syndrome. Acta Odontol Scand. 2001;59(3):116–20. doi:10.1080/000163501750266684 

11. Enger TB, Palm Ø, Garen T, et al. Oral distress in primary Sjögren’s syndrome: implications for health-related quality of life. Eur J Oral Sci. 2011;119(6):474–80. doi:10.1111/j.1600-0722.2011.00891.x 

12. Payne AG, Lownie JF, Van Der Linden WJ. Implant-supported prostheses in patients with Sjögren’s syndrome: a clinical report on three patients. Int J Oral Maxillofac Implants. 1997;12(5):679-85. 

13. Binon PP, Fowler CN. Implant-supported fixed prosthesis treatment of a patient with Sjögren’s syndrome: a clinical report. Int J Oral Maxillofac Implants. 1993;8(1):54–8. 

14. Drew HJ, Alnassar T, Gluck K, et al. Considerations for a staged approach in implant dentistry. Quintessence Int. 2012;43(1):29-36. 

15. Choi S, Yeo IS, Kim SH, et al. A root submergence technique for pontic site development in fixed dental prostheses in the maxillary anterior esthetic zone. J Periodontal Implant Sci. 2015;45(4):152–5. doi:10.5051/jpis.2015.45.4.152 

16. Chuang CJ, Hsu CW, Lu MC, et al. Increased risk of developing dental diseases in patients with primary Sjögren’s syndrome—A secondary cohort analysis of population-based claims data. PLoS One. 2020;15(9):e0239442. doi:10.1371/journal.pone.0239442 

17. Cordaro L, Torsello F, Ribeiro CA. Transition from a failing dentition to a removable implant-supported prosthesis: a staged approach. Quintessence Int. 2010;41(5):371–8. 

18. Papaspyridakos P. Full mouth implant rehabilitation with staged approach: 6-year clinical follow-up. J Esthet Restor Dent. 2015;27(4):213–23. doi:10.1111/jerd.12158 

19. Salama M, Ishikawa T, Salama H, et al. Advantages of the root submergence technique for pontic site development in esthetic implant therapy. Int J Periodontics Restorative Dent. 2007;27(6):521–7. 

20. O’Neal RB, Gound T, Levin MP, et al. Submergence of roots for alveolar bone preservation. I. Endodontically treated roots. Oral Surg Oral Med Oral Pathol. 1978;45(5):803–10. doi:10.1016/0030-4220(78)90158-5 

21. Dragoo MR. Resin-ionomer and hybrid-ionomer cements: part II, human clinical and histologic wound healing responses in specific periodontal lesions. Int J Periodontics Restorative Dent. 1997;17(1):75–87.

22. Greer BD, West LA, Liewehr FR, et al. Sealing ability of Dyract, Geristore, IRM, and super-EBA as root-end filling materials. J Endod. 2001;27(7):441–3. doi:10.1097/00004770-200107000-00001 

23. Al-Sabek F, Shostad S, Kirkwood KL. Preferential attachment of human gingival fibroblasts to the resin ionomer Geristore. J Endod. 2005;31(3):205–8. doi:10.1097/01.don.0000137650.61607.25 

24. Bidra AS. Three-dimensional esthetic analysis in treatment planning for implant-supported fixed prosthesis in the edentulous maxilla: review of the esthetics literature. J Esthet Restor Dent. 2011;23(4):219–36. doi:10.1111/j.1708-8240.2011.00428.x 

25. Bidra AS, Agar JR. A classification system of patients for esthetic fixed implant-supported prostheses in the edentulous maxilla. Compend Contin Educ Dent. 2010;31(5):366–8, 370, 372–4 passim. 

26. Simon H, Raigrodski AJ. Gingival-colored ceramics for enhanced esthetics. Quintessence Dent Technol. 2002;25:155–72.

27. Armellini D, von Fraunhofer JA. The shortened dental arch: a review of the literature. J Prosthet Dent. 2004;92(6):531–5. doi:10.1016/j.prosdent.2004.08.013 

28. Witter DJ, de Haan AF, Käyser AF, et al. A 6-year follow-up study of oral function in shortened dental arches. Part I: Occlusal stability. J Oral Rehabil. 1994;21(2):113–25. doi:10.1111/j.1365-2842.1994.tb01131.x

29. Hattori Y, Satoh C, Seki S, et al. Occlusal and TMJ loads in subjects with experimentally shortened dental arches. J Dent Res. 2003;82(7):532–6. doi:10.1177/154405910308200709 

30. Witter DJ, Cramwinckel AB, van Rossum GM, et al. Shortened dental arches and masticatory ability. J Dent. 1990;18(4):185–9. doi:10.1016/0300-5712(90)90107-p 

31. Daudt Polido W, Aghaloo T, Emmett TW, et al. Number of implants placed for complete-arch fixed prostheses: A systematic review and meta-analysis. Clin Oral Implants Res. 2018;29 Suppl 16:154–83. doi:10.1111/clr.13312

32. Gallucci GO, Avrampou M, Taylor JC, et al. Maxillary implant-supported fixed prosthesis: a survey of reviews and key variables for treatment planning. Int J Oral Maxillofac Implants. 2016;31 Suppl:s192–7. doi:10.11607/jomi.16suppl.g5.3 

33. Heydecke G, Zwahlen M, Nicol A, et al. What is the optimal number of implants for fixed reconstructions: a systematic review. Clin Oral Implants Res. 2012;23 Suppl 6:217–28. doi:10.1111/j.1600-0501.2012.02548.x 

ABOUT THE AUTHORS

Dr. Ramirez-Sosa received her BDS at Universidad Santa Maria in Venezuela, graduating in 2007. Then she broadened her expertise by completing a Certificate Program in Esthetic Dentistry from Universidad de Carabobo in 2010. For 7 years, she practiced dentistry in Venezuela, working in private and corporate sectors. Dr. Ramirez-Sosa continued her academic and professional journey at the Rutgers School of Dental Medicine (RSDM), where she completed her residency in prosthodontics in 2022. She can be reached via email at carmen.rsosa@gmail.com. 

Dr. Shah is a board-certified periodontist working in New York. Dr. Shah completed her DDS at University of the Pacific in 2017. After completing dental school, she worked in private practice as a general dentist for 2 years. Then she continued to complete her periodontal residency at Rutgers University, graduating in 2023. During her postgraduate tenure, Dr. Shah presented at the Northeastern Implant Symposium, served as chief resident, and was awarded the Michael J. Deasy Endowed Scholarship. She can be reached at serenashahdds@gmail.com.

Dr. Howard J. Drew is a professor, director of implantology, and the vice-chairman in the Department of Periodontics at RSDM. He received his doctorate and degree in periodontics from RSDM. He has been awarded the RSDM Excellence in Teaching Award and Stuart Cook Master Educators Guild Award, and he received the prestigious American Academy of Periodontology Educator Award. Dr. Drew was inducted into the American College of Dentists, and he was awarded the RSDM Alumni Association Decade (1980s) Award. He has authored more than 30 publications and has lectured throughout the country. He was in full-time clinical practice for more than 25 years. He can be reached at drhjdrew@aol.com.

Dr. Alexander S. Drew is a maxillofacial prosthodontist with a private practice in Summit, NJ, limited to prosthodontics and restorative dentistry. He received his DMD degree from the University of Pennsylvania. After completing dental school, he earned a specialty certificate in prosthodontics and a masters of science degree from the Columbia University College of Dental Medicine where he was the chief resident. He then completed a subspecialty fellowship in maxillofacial prosthetics and was awarded a certificate from Memorial Sloan Kettering Cancer Center. Dr. Drew is a member of the American College of Prosthodontics and the ADA. He is an associate fellow of the American Academy of Maxillofacial Prosthetics and author to research publications in high-impact scientific journals. He can be reached at asdrew1@gmail.com.

Dr. Cappetta is the director of the postgraduate program of periodontics at RSDM. He received his doctorate from Rutgers University and his periodontics degree from Boston University. Dr. Cappetta has authored numerous publications in multiple periodontal journals, ranging from implant-supported prosthetics to novel mucogingival surgeries.He can be reached via email at cappeteg@sdm.rutgers.edu.

Dr. Falcon is a board-certified endodontist and director of the Advanced Specialty Education Program in Endodontics at RSDM in Newark, NJ. He has maintained private practice for 40 years. He has served nationally as District II Director on the American Association of Endodontists’ Board of Directors. He is presently President of the New Jersey Association of Endodontists. He can be reached at falconpa@sdm.rutgers.edu.  

Disclosure: The authors report no disclosures. 

In the realm of contemporary dental practice, intricate cases often provide opportunities to demonstrate the integration of innovative technology and comprehensive clinical management. This case study presents a nuanced account of a patient who presented with a challenging dental scenario necessitating a multifaceted approach to restoration. The primary aim of this study is to illuminate the diagnostic process, treatment planning, and execution of a complex dental reconstruction supported by state-of-the-art techniques and equipment.

CASE REPORT 

Patient Presentation 

A female patient sought dental care at our clinic with a notable dental challenge. She presented with a previously placed 3-unit bridge on teeth Nos. 8 through 10 that had deteriorated to the point of being non-restorable (Figures 1 and 2). The cause of this bridge failure was attributed to a combination of a deep bite and occlusal trauma. Adding to the complexity, tooth No. 7 displayed mobility as a result of prior periodontal disease, rendering it unsuitable as a viable abutment for a new bridge (Figure 3).

Figure 1. Preoperative patient smile. Note the high smile-line and fractured teeth Nos. 8 and 10.

Figure 2. Pre-op image showing the deep bite contributing to fracture.

Figure 3. Pre-op x-ray showing minimal bone around No. 7 and a fractured root tip on No. 8.

Of note, the patient had been employing an Essix Appliance for more than a year and a half before discovering our practice. The Essix Appliance, a form-fitting, transparent shell, had been instrumental in maintaining tooth positions and aiding retention.

Despite recognizing the need for treatment, the patient hesitated to seek care due to her specific requirements. She was determined to find a dentist capable of comprehensively managing her case without the need for referrals to multiple specialists. Moreover, she was adamant about receiving care that incorporated the latest advancements in dental technology.

Remarkably, the patient sought our practice for more than just clinical expertise. She was drawn by our practice’s reputation for housing state-of-the-art technology and, importantly, a singular dentist capable of orchestrating every facet of her care. The patient’s insistence on avoiding multiple offices underscored the appeal of having a unified approach to her treatment, encompassing the roles of the restoring doctor, surgeon, and even lab technician, all under one roof.

Treatment Plan

Upon thorough examination, it became evident that attempting to restore the compromised bridge would yield a poor prognosis. As such, a decision was reached to extract teeth Nos. 7, 8, and 10 and to promptly replace them with implants at position Nos. 7 and 10. This intervention would involve employing partial extraction therapy and grafting techniques.

Utilizing a combination of preoperative CAD/CAM data and CBCT scans obtained through Orthophos SL 3D (Dentsply Sirona), a meticulous implant placement strategy was formulated with the aid of SICAT software (Figure 4). This software not only facilitated precise planning but also guided the creation of a surgical guide designed using the CEREC inLab system (Dentsply Sirona) and subsequently produced via a Primeprint 3D Printer (Dentsply Sirona).

Figure 4. SICAT planning software with CAD/CAM imaging correlated.

Following the healing period, an intraoral scan would then be captured using Primescan technology (Dentsply Sirona) and employing intraoral FLO scan bodies. This digital scan would serve as the foundation for the design and fabrication of custom Atlantis abutments (Dentsply Sirona). Subsequently, a provisional bridge would be generated through 3D printing.

As the pontic sites matured, the final fixed bridge spanning teeth Nos. 7 to 10 would be crafted using the innovative KATANA Zirconia ONE material (Kuraray Noritake). The overarching treatment objective was twofold: to reinstate the patient’s missing teeth and, crucially, to rectify the deep bite surgically and restoratively. This comprehensive approach aimed to mitigate unfavorable occlusal forces on the new implant-supported bridge.

Treatment Execution and Clinical Outcomes

The foundation of our treatment approach rested on comprehensive records that provided us with invaluable insights. High-quality clinical photography, supplemented by intraoral x-ray images, allowed for a detailed assessment of the patient’s oral condition. However, the key to precision lies in the utilization of advanced imaging modalities. CBCT scans provided intricate 3D reconstructions, granting a deeper understanding of the patient’s bone structure and aiding in implant placement planning.

The integration of CAD/CAM technology was pivotal. Diagnostic wax-ups were meticulously crafted, facilitating visualization and communication of the intended treatment outcomes. This stage was particularly crucial for establishing the desired occlusal relationships and guiding the subsequent steps of the treatment plan. Precise calculations were conducted to determine the optimal bone reduction necessary to address the gummy smile and ameliorate the deep bite, ensuring a harmonious final result.

Dental Extractions and Immediate Implant Placement

With a comprehensive treatment plan in hand, dental extractions were performed, accompanied by partial extraction therapy to preserve the alveolar bone architecture. This meticulous approach was coupled with bone grafting to augment the sites for future implant placement. Immediate implant placement was executed at position Nos. 7 and 10, laying the groundwork for the eventual implant-supported bridge (Figures 5 and 6). To maintain the gains achieved during this phase, an Essix retainer was employed. This interim measure provided stabilization while minimizing the potential for undesirable tooth movement.

Figure 5. Implant placed on No. 7.

Figure 6. Implant placed on No. 10.

Uncovering and Healing Abutments

After the healing period, uncovering of the implants was undertaken. Healing abutments were positioned, enabling unimpeded tissue healing and facilitating the emergence profile.

Abutment Fabrication

Precision at every stage was our guiding principle. To this end, intraoral FLO scan bodies were integrated into the workflow, and digital scans were obtained for the design and fabrication of custom Atlantis abutments (Figure 7). These abutments, crafted from gold-hue titanium, were meticulously designed to ensure optimal fit and emergence profile, reinforcing the aesthetic and functional goals of the treatment (Figure 8).

Figure 7. Surgical guides designed with inLab Software (Dentsply Sirona).

Figure 8. Custom abutments designed with Atlantis Editor (Dentsply Sirona).

Provisional Bridge Design and Fabrication

An integral stage of the treatment plan involved the design and fabrication of a provisional bridge to develop the pontic sites (Figures 9 and 10). Leveraging 3D printing technology through our Primeprint 3D printer, a provisional bridge was crafted. This intermediary step allowed for precise pontic development, ensuring optimal soft-tissue contours and enhancing the overall aesthetic outcome.

Figure 9. A temporary bridge for pontic development was 3D printed with Primeprint (Dentsply Sirona).

Figure 10. Pontic sites developed and ready for the final bridge.

Final Bridge Design and Fabrication

The penultimate stage heralded the transition to the fabrication of the final fixed bridge spanning teeth Nos. 7 to 10 (Figure 11). Iterative modifications to the design were meticulously carried out, culminating in a digital blueprint that captured the desired functional and aesthetic considerations. Milling, contouring, and glazing of the KATANA Zirconia ONE bridge were undertaken in-house, facilitated by the collaborative use of lab technologies. The final product seamlessly married form and function, delivering an exceptional final result (Figures 12 and 13).

Figure 11. The 4-unit bridge (post-sinter) made with KATANA Zirconia ONE (Kuraray Noritake).

Figure 12. Final bridge.

Figure 13. Postoperative smile.

CONCLUSION

In conclusion, this intricate and multifaceted treatment journey underscores the power of technology-enabled dentistry. The judicious integration of advanced imaging, CAD/CAM systems, 3D printing, and collaborative lab technologies not only facilitated precision and efficiency but also contributed to patient confidence and acceptance. 

The seamless orchestration of each step under a single practitioner’s guidance exemplified our commitment to holistic, patient-centered care, while the culmination of efforts in the form of a meticulously designed and crafted bridge bore testimony to the synergy between art and science in modern dental practice.

The patient’s satisfaction with the treatment was evident, reflecting the favorable outcomes and streamlined process of the intricate treatment plan. Her contentment resonated not only with the achieved results but also with the systematic and effective navigation through the comprehensive therapeutic regimen. This positive response underscored the synergy between advanced dental techniques and meticulous clinical management, exemplifying the convergence of patient-centric care and contemporary dentistry.

While the role of technology undoubtedly streamlined the delivery of this intricate treatment, the patient’s agreement with the proposed plan was heavily influenced by the perception of our practice’s technological capabilities. Beyond the treatment itself, effective communication of our practice’s technology-focused approach played a pivotal role in fostering patient trust and case acceptance.

Furthermore, the integration of technology into our workflow was contingent on its ease of use and compatibility with our established processes. This consideration extended to the meticulous selection of equipment, ensuring that each component seamlessly contributed to a patient-centered and efficient treatment journey.

ABOUT THE AUTHOR

Dr. Apekian graduated from the University of California (UC), Davis, with a degree in neurobiology, physiology, and behavior. She earned her DDS degree from UC, San Francisco (UCSF), where she graduated top of her class. She is active in the Sacramento District Dental Society, serving as the legislative committee chair, as well as serving on the Continuing Education, Ethics, and Leadership Committees. She has also represented Sacramento at the California Dental Association (CDA) House of Delegates. Dr. Apekian is an active member of the CDA, ADA, and UCSF Alumni Association. She recently built and designed one of the most technologically advanced dental offices, utilizing CAD/CAM technologies, 3D imaging, state-of-the-art infection control systems, and full digital integration. She is a graduate of the Sacramento Implant Continuum and utilizes the latest technology for guided implantology. She also serves as a mentor and trainer for Dentsply Sirona’s CEREC CAD/CAM technology throughout the Sacramento, Calif region. She teaches fellow dentists how to utilize the technology to design and produce complete restorations, surgical guides, and appliances for prosthetics, implantology and orthodontics. She can be reached at gotfloss@gmail.com. 

Disclosure: Dr. Apekian has financial interests in Kuraray Noritake and Dentsply Sirona.  

The replacement of a full arch of failing teeth has long been seen as the panacea of implant dentistry. The All-on-4 protocol as described by Malo et al¹ has shown excellent implant and prosthetic success rates. Traditional analog workflows included:

1. Preliminary diagnostic impressions
2. Diagnostic trial setup
3. Surgical procedures, including analog impressions
4. Try-in/bite verifications
5. Insertion of temporary prostheses

These additional steps increase the overall time taken for prosthesis delivery as well as costs. Continuing development in additive manufacturing (3D printing) has resulted in predictably accurate prints. The resins used in contemporary 3D printing have been shown to have physical properties similar to milled polymethylmethacrylate (PMMA)² and can now be printed on “desktop” printers.

In addition to the improved speed and accuracy of 3D printed restorations, the implementation of photogrammetry allows for the accurate capture of implant positions, ensuring the delivery of a completely passive prosthesis.³

The use of CAD software (exocad) enables rapid production of a digital file, which, when combined with all the relevant preoperative and intraoperative data, allows the clinician to quickly approve the case design and proceed to prosthesis fabrication. This case report describes a simplified, completely digital workflow for the provision of a full-arch temporary prosthesis within 24 hours.

CASE REPORT

A patient presented with a partially dentate mandible and a failing acrylic lower partial denture (Figure 1) and requested a fixed solution with the specific desire of being “able to bite into an apple.” His existing vertical dimension of occlusion (VDO) was satisfactory, and the initial CBCT was performed with the patient in occlusion at this VDO (Figure 2). This pre-op CBCT will provide a reference for relating the postoperative CBCT back to the patient’s original vertical dimension. If any alterations are anticipated, it is important to perform these prior to the diagnostic CBCT either by addition of composite to existing teeth in dentate patients or by fabrication of a denture at the correct VDO in edentulous patients. 

Figure 1. The patient presented with a partially dentate mandible and failing teeth Nos. 22 and 27.

Figure 2. Preoperative CBCT taken to document the original vertical dimension.

Figure 3. The exocad design file.

Additional diagnostic data collected at this appointment included intraoral scans (i700 [Medit]), DSLR photography, and a 3D face scan (Vectra Smile [JK Dental Group]). All of the diagnostic data was merged in exocad to create a digital patient (Figure 3). 

Implant planning was performed using Blue Sky Plan planning software (BlueSkyBio) to ensure adequate available bone was present to place and immediately load the implants (Figure 4). Freehand surgery was performed on the patient under IV sedation.

Once surgery was completed, and before surgical closure, iCam body scans were performed using Imetric 4D Imaging photogrammetry (Figures 5 to 7).

Figure 4. Surgical planning in Blue Sky Plan planning software (BlueSkyBio).

Figure 5. Mandible after alveolectomy for prosthetic space.

Figure 6. Implants placed.

Figure 7. Implants with iCam body scans (Imetric 4D Imaging photogrammetry) attached.

A post-op CBCT scan was taken to generate 2 STL files from DICOM data by altering thresholds: 

1. An STL of iCam reference scan bodies for stitching to soft tissue (increasing the Hounsfeld unit threshold).
2. An STL of hard tissues to relate to pre-op CBCT within Imetric software (lowering Hounsfeld unit threshold).

All diagnostic data were aligned and exported to exocad for the generation of an STL file of the provisional prosthesis.

The prosthesis was designed in exocad CAD software (Figures 8 and 9), and 3D printing was performed on an Ackuretta Sol printer using Rodin Sculpture A1 Resin (Pac-Dent) following the manufacturer’s settings. Optimal support settings were generated by the AI software. 

Figure 8. Prosthesis design.

Figure 9. Nesting in printing software.

Rodin Sculpture (Figure 10) is a new ceramic nanohybrid resin that streamlines the fabrication process while reducing manufacturing costs for both clinicians and dental laboratories. It is an FDA 510(k)-cleared, biocompatible, light-curable resin designed to be used with specific CAD/CAM systems in combination with manufacturer-validated 3D printing and light-curing devices. This new resin can be used to fabricate permanent full-contour crowns, inlays, onlays, and veneers. In addition, it can be used to fabricate All-on-X immediate prostheses, monolithic dentures, and split-file denture tooth arches. It is composed of the same resin components found in most restorative composites with the addition of a high concentration of true nano-ceramic fillers that provide brilliant radiopacity. 

Rodin was chosen for its excellent mechanical properties coupled with its lifelike translucency. It offers the highest flexural strength and modulus of any long-term/permanent restoration and features lifelike aesthetics. It is also highly break-resistant, reducing the incidence of repairs and remakes. 

After printing, the prosthetic was removed from the build plate, and the supports were removed (Figures 11 and 12). Next, it was carefully washed with isopropyl alcohol to remove excess uncured resin. The support tips were finished smooth with a low-speed handpiece and a finishing bur. The denture was then polished with pumice and acrylic polishing compound for a final finish.

Figure 10. Rodin Sculpture (Pac-Dent).

Figure 11. Printed prosthesis on build plate.

Figure 12. Prosthesis prior to cleaning.

Gingival staining and glazing were achieved using denture stain elixirs (Larry’s Magical Denture Elixirs [TAUB Products]) and Rodin Palette glaze for surface characterization (Figure 13). The prosthesis was then light-cured in the Ackuretta Curie unit. 

The following morning, the provisional prosthesis was delivered with polymer-specific prosthetic screws. No occlusal adjustment was needed. When designing the prosthesis, care was taken to minimize cantilever length and respect minimum thickness around implant access channels.

Figure 13. Staining and glazing of prosthesis.

Figure 14. (a) Temporary prosthesis at initial delivery and (b) at 6 months in function prior to proceeding to the definitive restoration.

Figure 15. Intraoral situation prior to the definitive restoration.

The photos in Figure 14 show the temporary prosthesis at delivery and at 6 months in function prior to proceeding to the definitive restoration. Figure 15 shows the healing underneath the printed bridge, which demonstrates the biocompatibility of the Rodin material.

REFERENCES

1. Malo P, de Araújo Nobre M, Lopes A, et al. A longitudinal study of the survival of All-on-4 implants in the mandible with up to 10 years of follow-up. J Am Dent Assoc. 2011;142(3):310–20. doi:10.14219/jada.archive.2011.0170 

2. Alageel O, Alsadon O, Almansour H, et al. Assessment of effect of accelerated aging on interim fixed dental materials using digital technologies. J Adv Prosthodont. 2022;14(6):360–8. doi:10.4047/jap.2022.14.6.360 

3. Ma B, Yue X, Sun Y, et al. Accuracy of photogrammetry, intraoral scanning, and conventional impression techniques for complete-arch implant rehabilitation: an in vitro comparative study. BMC Oral Health. 2021;21(1):636. doi:10.1186/s12903-021-02005-0 

ABOUT THE AUTHOR

Dr. O’Dowling graduated from University College Cork, Ireland, in 2006, where he was awarded the Noel Hayes Award for Oral Surgery and the British Undergraduate Society Award for Restorative Dentistry, and he was accepted as a member of the Student Clinicians of the American Dental Association for his project work on molar/incisor hypomineralisation. He has worked in private practice in Ireland and in Queensland and Perth, Australia. During this time, he has continued to advance his knowledge in implant surgery and prosthetics and completed his MSc in Oral Implantology in 2018 from Goethe Dental School (Frankfurt, Germany). He is a Diplomate of both the International Congress of Oral Implantologists and the American Board of Oral Implantology/Implant Dentistry and a Fellow of the American Academy of Implant Dentistry. Dr. O’Dowling maintains a keen interest in all aspects of implantology, ranging from simple implant placement to advanced techniques such as partial extraction therapy, autogenous bone plates, and sinus augmentations. His current focus is the simplification of full-arch restorative protocols utilizing digital techniques and 3D printing. He can be reached at daveodowling83@gmail.com. 

Disclosure: Dr. O’Dowling reports no disclosures. 

Transitioning from a terminal dentition to complete dentures can be an aesthetic and functional challenge. Immediate complete dentures (ICDs) are prosthetics that are inserted at the time of extraction. They can serve a crucial role, as they allow patients to maintain prosthetics throughout their transition to edentulism. They can offer many other benefits to patients, including soft-tissue support, maintenance of vertical dimension of occlusion, and more predictable healing of the ridges and soft tissue.^1-3 

Immediate complete dentures are not without their disadvantages; unlike conventional complete denture workflows, clinicians cannot complete a full clinical try-in. This leads to unpredictability, not only in anterior aesthetics but also in function. Without this step, it is difficult to communicate what wearing a denture will feel like or if the patient can even tolerate the sensation on the palate. Additionally, establishing centric relation position can be particularly challenging in the presence of a mobile, painful, or otherwise compromised terminal dentition. 

There are 2 categories of immediate dentures: (1) classic immediate dentures (D5130/D5140), which are intended to serve as a long-term definitive restoration, and (2) interim immediate dentures (D5810/D5811), which are intended to be replaced after healing. The greatest benefit of classic immediate dentures is the cost to the patient. Although these are typically done for a higher fee than other types of complete dentures, the patient is only responsible for the cost of one set of dentures. With interim immediate dentures, the initial cost is lower, but the patient will pay for a second set of conventional dentures (or implant overdentures) after healing. This allows the clinician to make changes to the tooth arrangement in the definitive set, improving aesthetics and function.³ No matter the type of prosthesis chosen, digital dentistry can help increase the predictability of immediate complete dentures and shorten the workflow.

While ICDs were first introduced in the literature in the 1930s,² the protocol remained very similar until the advent of digital dentures in the 2010s. There is now widespread use of intraoral scanning for immediate and other complete dentures.⁴ A decade after the commercial availability of digital dentures,⁵ there are now numerous case reports incorporating scanning into ICD workflows.^6-9 The following case report walks through a fully digital workflow to fabricate an immediate complete denture.

CASE REPORT

An 83-year-old, long-term patient of the practice had been maintaining her dentition through routine periodontal maintenance and with a transitional  removable partial denture (RPD) (Figure 1). She presented to an emergency appointment with a chief concern of pain in her upper left molars. After a clinical exam including endodontic testing, it was determined that both of her upper left molars would require root canal therapy. Due to canal calcification, the result would be unpredictable. She was not interested in proceeding with that plan and requested extraction. She was advised that with extraction of the 2 painful teeth, her remaining maxillary dentition could no longer predictably support an RPD as she carried a diagnosis of periodontitis in her maxillary dentition (stage 3, grade B) concurrent with diabetes and traumatic occlusion due to loss of posterior support. She had Class II mobility on her remaining maxillary anterior teeth and Class I mobility on her maxillary molars. After inviting and answering questions, the patient was eager to proceed with an interim immediate complete denture, followed by the fabrication of a definitive complete denture.

Figure 1. The patient presented with irreversible pulpitis on teeth Nos. 14 and 15. Endo prognosis was poor, and the patient did not want to proceed with the procedure. Due to lack of remaining stable abutment teeth, an interim immediate complete maxillary denture was treatment planned.

The patient was very aesthetics-focused and requested that the shape and size of the anterior teeth of her interim immediate denture resemble her current dentition. To more predictably achieve this goal, a digital workflow was chosen. Due to her reduced periodontium, odontogenic pain, and the mobility of her maxillary teeth, an intraoral scan was used for the final impression. 

A complete denture design using the denture module  on the 3Shape Dental System (3Shape) was used, morphing the anterior design to follow the patient’s existing teeth. Bilateral balanced occlusion was designed in excursive movements in the software (Figure 2). The teeth were nested in segments and fabricated along with the base using additive manufacturing (carbon M3) with denture tooth and base resins (Lucitone Digital Print Denture System [Denstply Sirona]). The teeth were fused to the base, and the prosthesis was finished and polished.

Figure 2a. The patient’s pretreatment scan was loaded into the design software.

Figure 2b. A tooth mold was chosen from the 3Shape library that closely matched the patient’s existing centrals, and the teeth were morphed to match more closely.

Figure 2c. The complete immediate den- ture arrangement was finalized based on the opposing dentition.

Care was coordinated with an oral maxillofacial surgeon, who extracted the remaining maxillary dentition with local anesthesia. At the completion of extractions, the denture was relieved of high spots and relined with a chairside soft reline material (COE-SOFT [GC America]), and occlusion was adjusted for bilateral balance (Figure 3). This prosthesis was worn and maintained with chairside reline (COE-SOFT) for approximately 6 months following standard protocol (Figure 4).

Figure 3. The immediate complete denture at the time of insertion.

Figure 4. The prosthesis was maintained with chairside soft reline for about 6 months.

At a follow-up appointment, the requested changes were discussed with the patient. Vertical dimension of occlusion and bilateral balanced occlusion were verified. The patient was happy overall with aesthetics but wanted a slightly bolder and larger mold. The midline was also adjusted. The changes were minimal, and though the monolithic try-in could have been skipped, the patient preferred a try-in before proceeding with the final prosthetics.

The soft reline had been well-adapted and contoured, with the prosthesis having excellent support, stability, and retention. Subsequently, a reference denture workflow followed, scanning the prosthesis (intaglio and teeth), along with the opposing dentition, and a centric relation scan was also taken (Figure 5). These were uploaded into design software, and changes were incorporated before printing the monolithic trial denture (Figure 6).

Figure 5. The prosthesis was scanned, along with the opposing dentition and interocclu- sal record, so that the laboratory could follow a reference denture workflow.

At the try-in, the clinician and patient walked through the checklist together (Appendix 1), and no changes were needed. The try-in was printed in an FDA-cleared resin (Lucitone Digital Value [Dentsply Sirona]), and the patient was sent home with the trial denture to identify any sore spots prior to the insertion visit. The definitive dentures were fabricated with the same materials and method as the ICDs. 

Appendix 1

The dentures were inserted and adjusted following conventional protocols (Figures 6 and 7). 

Figure 6. The monolithic printed try-in was completed to verify changes in fit and aesthetics.

Figure 7. Final prosthesis after healing.

DISCUSSION

Immediate dentures serve a role in preserving function and quality of life after extraction. One must consider, though, they are not without their disadvantages. Literature and clinical experience from providers corroborate the narrative that immediate complete dentures are a consistent challenge. After working with numerous students and clinicians over the years, one of the biggest frustrations with complete dentures in general is the lack of predictability. There is so much room for error along the often long and tumultuous process that it can prove to be frustrating to both clinicians and patients. Following conventional denture workflows, records are destroyed; a remake or modification often requires going back several steps to regain traction. Immediate denture workflows amplify this challenge. The unpredictability is greater due to lack of try-in, and going back to pre-extraction records is virtually unachievable. 

CAD/CAM dentures overcome some of these challenges. The preservation of records is often an underappreciated aspect of the workflow. By merging files and photos and customizing molds for the patient, we can now achieve results that would be impossible through conventional workflows. Clinicians can go back to a previous try-in or remake a denture without any additional clinical steps. In other words, the process is more predictable—and less stressful. 

Often, the monolithic try-in has a steep learning curve for clinicians new to digital dentures. Included here is a checklist that has helped my students and me through the learning process (Appendix 2). This monolithic trial denture can be quite versatile. It may be partially printed for immediate dentures. If printed in an FDA-cleared resin, it may be worn as an interim denture or worn home short- or long-term for the patient and family to evaluate function and aesthetics. It can then be maintained by the patient as a “backup denture” if something were to happen to his or her prosthesis.

 CLOSING COMMENTS

Historically, classic (or conventional) immediate dentures were more common, using the immediate denture as a definitive prosthesis. In this workflow, typically, posterior teeth were removed and custom impression trays were made after healing, then conventional border molding, records, and posterior tooth try-ins were completed before processing. While this achieved the best possible result, unpredictable surgical healing, lack of a try-in, and patient factors remained a challenge. With the ability to duplicate and preserve records, perhaps a paradigm shift toward interim immediate dentures should be considered. Overall, the workflow presented (interim immediate followed by reference/copy denture) should typically result in fewer clinical appointments and less chair time than the conventional/classic immediate denture workflow (Appendix 2).

Appendix 2. Proposed digital immediate complete denture workflow.

Another benefit of digital dentistry in the immediate denture workflow is the ability to scan the final impression. When patients are missing many teeth, particularly in the posterior mandible, the soft-tissue scan can be a challenge, and a conventional impression is often the best choice. When many teeth are remaining, however, intraoral scanning becomes much easier.

To summarize, there is not one correct workflow for complete dentures. CAD/CAM offers clinicians numerous ways to improve the complete denture workflow and customize it to work for their practices.

REFERENCES

1. Kelly EK, Sievers RF. The influence of immediate dentures on tissue healing and alveolar ridge form. J Prosthet Dent. 1959;9(5):738–42.

2. Seals RR Jr, Kuebker WA, Stewart KL. Immediate complete dentures. Dent Clin North Am. 1996;40(1):151–67. 

3. Rahn AO, Ivanhoe JR, Plummer KD. Textbook of Complete Dentures. 6th ed. Shelton,CT: People’s Medical Publishing House; 2009.

4. AlRumaih HS. Clinical applications of intraoral scanning in removable prosthodontics: a literature review. J Prosthodont. 2021;30(9):747–62. doi:10.1111/jopr.13395 

5. Goodacre CJ, Garbacea A, Naylor WP, et al. CAD/CAM fabricated complete dentures: concepts and clinical methods of obtaining required morphological data. J Prosthet Dent. 2012;107(1):34-46. doi:10.1016/S0022-3913(12)60015-8 

6. Mendonça G, Edwards SP, Mayers CA, et al. Digital immediate complete denture for a patient with rhabdomyosarcoma: a clinical report. J Prosthodont. 2021;30(3):196-201. doi:10.1111/jopr.13305

7. Neumeier TT, Neumeier H. Digital immediate dentures treatment: a clinical report of two patients. J Prosthet Dent. 2016;116(3):314–9. doi:10.1016/j.prosdent.2016.01.010 

8. Fang JH, An X, Jeong SM, et al. Digital immediate denture: a clinical report. J Prosthet Dent. 2018;119(5):698-701. doi:10.1016/j.prosdent.2017.06.004

9. Clark WA, Duqum ID. Dentsply Sirona: Lucitone Digital Print Denture. LMT Communications. 2021. 

ABOUT THE AUTHOR

Dr. Clark completed her doctoral degree from the Marquette University School of Dentistry in Milwaukee and earned her master’s degree in clinical dentistry and certificate in postgraduate prosthodontics from the University of Alabama at Birmingham School of Dentistry. She practiced prosthodontics for 7 years with Team Atlanta (Goldstein, Garber, and Salama), before her current full-time prosthodontic faculty role in at the University of North Carolina Adams School of Dentistry. She has been named a “Leader in Continuing Education” by Dentistry Today for the last 6 years, presenting on a wide range of prosthodontic topics. She recently received the young alumna of the year award from the Marquette University School of Dentistry and the Hunt Memorial Teaching Award from the University of North Carolina Adams School of Dentistry. She has published articles in numerous peer-reviewed journals and serves as a key opinion leader for multiple companies on digital dentures. She can be reached at wendyauclair@gmail.com. 

Disclosure: Dr. Clark serves as a KOL for Avadent Digital Dentures and Dentsply Sirona, but she received no compensation for writing this article.

In today’s society, we are seeing more and more patients presenting with teeth that are severely broken down either from decay, wear, or periodontal disease. Our goal as dental providers is to treat the various dental problems these patients present with to maintain an oral environment that is healthy, functional, and aesthetic. However, there comes a time when all the various dental treatments are exhausted, and tooth removal is necessary.

This article describes a patient who was referred to me by a colleague for full-mouth dental implant reconstruction because all her previous treatments were no longer maintaining a healthy periodontium. 

CASE REPORT

Initial Consultation

A patient in her mid-60s presented to my practice and was referred to me by her general dentist for an evaluation of her existing dental condition in both her maxillary and mandibular arches (Figure 1). The patient informed me that there were several areas where the teeth felt loose and uncomfortable. In fact, a portion of her upper left, fixed, partial denture had been recemented several times to try to buy the patient some time before deciding on what treatment she would pursue. Her main concern was restoring her dentition to proper form, function, and aesthetics, even if it meant extracting all her existing teeth.

Figure 1. Preoperative smile view.

Figure 2. Pre-op retracted bite view.

Figure 3. Pre-op retracted open bite view.

Upon clinical examination, it was very apparent that, in the past, the patient had already undergone extensive restorative and prosthetic rehabilitation by trying to save her teeth with multiple areas of crowns and bridges (Figures 2 and 3). Due to the recent loss of her posterior maxillary and mandibular teeth within the last few years, the patient’s vertical dimension was showing signs of collapse, causing further force and wear on her anterior teeth and restorations. Deep periodontal probing depths in many areas indicated localized periodontitis in most of her remaining teeth. It was also noted that there were several areas in the gingival tissue where there appeared to be “amalgam tattoos,” which were signs that some of these teeth were possibly treated with apicoectomies. When asked, the patient did mention that several of these teeth had been treated on multiple occasions with endodontic therapy, followed by apical surgery, to try to maintain these teeth as long as possible. Reviewing her radiographs (XDR Radiology) as well as her CBCT scans (CS 8100 [Carestream Dental]), it was very apparent that several teeth in the maxillary arch were treated with endodontic treatment followed by apical surgery (Figure 4). Additionally, there were several areas of recurrent decay at the margins of the dental restorations. Bone loss was also very evident in the radiographs and CBCT images.

Figure 4. CS 8100 (Carestream Dental) 3D view.

All risks, benefits, and alternatives of various treatments were reviewed with the patient. It was decided that the treatment that would provide the best prosthetic, functional, and aesthetic outcome for the patient with a good long-term prognosis would be to remove all the remaining teeth and replace them with fixed, full-arch, implant-retained restorations. 

Planning

Once the patient confirmed that she would like all her remaining teeth extracted, our goal was to plan the placement of dental implants in regions of bone so that the final fixed restorations would be biomechanically stable. Using the CS 8100 planning software, we virtually positioned the placement of dental implants according to an adaptation of Misch’s principles in full-mouth dental implant reconstructions (Figure 5). Misch developed a treatment plan sequence to decrease the risk of biomechanical overload to a fixed implant prosthesis consisting of (1) prosthesis design, (2) key implant positions for the prosthesis, (3) patient force factors, (4) bone density in the edentulous sites, (5) implant number beyond key positions, (6) implant size, (7) available bone in the edentulous sites, and (8) implant design.¹ Since the patient’s bone was somewhat compromised in the areas of the apicoectomies, it was decided to place additional dental implants in those regions to ensure a more successful outcome. When selecting dental implants for immediate loading of a full-arch, fixed provisional restoration, one should choose an implant with a slightly tapered design, aggressive threads, and a prosthetic platform design that preserves crestal bone. The dental implant of choice for this reconstruction was Touareg OS dental implants (Adin Dental Implants) because of its self-tapping and bone-condensing design that achieves high primary stability. Additionally, these dental implants feature a calcium phosphate gritting media surface treatment, OsseoFix (Adin Dental Implants), to achieve the desired roughness for optimum osseointegration.

Figure 5. Treatment planning of dental implants.

When planning for the placement of dental implants for full-mouth reconstruction, several anatomic factors need to be evaluated by the solo dental/surgical provider or dental team (specialist and restorative dentist). These include, but are not limited to^2-4: 

1. The magnitude of the 3D anatomical defect

2. The visibility of the prosthetic transition line

3. The volume and quality of available bone in the maxillary zones

4. The position of the inferior alveolar nerve and mental foramen

Utilizing these principles, a virtual treatment plan was forwarded to Pittman Dental Laboratory (Gainesville, GA) and ITX Pros (Tampa, Fla) to further complete the planning and ultimately design surgical guides. In the lab, the patient’s digital data, including images of her dentition and smile, along with impressions of the teeth (Silginat [Kettenbach LP]), were merged with the underlying 3D bone structures taken from the CBCT scan (Carestream Dental). Once the data was fused, it served as the foundation for a virtual online meeting that included the dental provider, the doctor on staff at ITX Pros, and the lab technician (Pittman Dental Laboratory). The virtual workup was based on all the assembled digital and clinical information from the respective dental provider and laboratory personnel. The treatment plan that was formulated among all the team members included optimal implant position, size, depth, and orientation. Using eDentalCAD software (exocad), the dental laboratory also designed the implant-supported, immediate, fixed, maxillary and mandibular PMMA prostheses.

Figure 6. Surgical guides and provisional restorations.

Once the planning was completed amongst the collaborative teams, all the components for the surgery were fabricated and delivered to the dental office.^5,6 These components included the bone foundation guides, surgical implant guides, and PMMA immediate provisional restorations (Figure 6). Necessary bone retention pins with respective drills were also provided in the package for proper anchorage. Before use, these components would be sterilized using cold sterilization.

Surgery

On the day of surgery, the patient was appropriately sedated with IV medications, and local anesthesia was administered in both the maxillary and mandibular regions. Since the patient’s maxillary teeth exhibited Class III mobility, the bone foundation guide would be positioned on the patient’s anterior nasal spine for greater stability after removal of her maxillary teeth (Figure 7) with the GoldenForce Forceps (GoldenDent). A full-thickness flap was reflected (Figure 8) using the Reflector (GoldenDent) on the facial aspects of the ridge, and the bone foundation guide was secured with bone screws. Bone leveling was accomplished using a surgical motor (AEU-7000 [Aseptico]) and handpiece (Mont Blanc [Anthogyr]) with copious amounts of sterile saline irrigation (Figure 9). 

Figure 7. Extractions using GoldenForce Forceps (GoldenDent).

Figure 8. Reflecting tissue with a Reflector instrument (GoldenDent).

Figure 9. Bone leveling with a surgical handpiece.

Figure 10. A surgical implant guide (Pittman Dental Lab/ITX Pros).

Once the bone was relieved to the level of the guide, the implant surgical guide was positioned and secured into the bone foundation guide (Figure 10). Following the instructions from the dental lab and planning company (Pittman Dental Laboratory, ITX Pros), a drilling protocol was utilized with Adinguide (Adin Dental Implants), a CBCT guided drilling and implant insertion kit (Figure 11). Some of the advantages that I have personally found with this system is the keyless, self-centering drills that have built-in stoppers to ensure precise and accurate drilling to the desired depth. Most importantly, the Adinguide’s ActiveFlow irrigation technology design forces coolant through the guide to ensure that the irrigation reaches the bone, preventing overheating. Once the sequential drilling was completed, the dental implants (Touareg OS) were inserted with fixed implant drivers through the sleeves of the surgical guide (Figure 12). The dental operator may use either a hand-operated ratchet or a handpiece adapter to insert the dental implant at a recommended torque of 50 Ncm. 

Figure 11. Adinguide (Adin Dental Implants).

Figure 12. Implant insertion drivers.

Figure 13. Occlusal view of transmucosal abutments.

Figure 14. Maxillary PMMA provisional restoration.

To ensure the correct orientation of the internal hex component, an occlusal view of the placed implants was inspected (Figure 13), followed by the placement of the transmucosal abutments (Adin Dental Implants). These multi-unit abutments were torqued to a level of 25 to 30 Ncm. The PMMA provisional restoration (Pittman Dental Laboratory) was then positioned over the prosthetic guide that was secured into the bone foundation guide (Figure 14). Using Quick Up (VOCO), a gingiva-colored composite for luting attachments, the temporary cylinders were picked up. The ideal combination of self-curing and light curing ensured full setting before the provisional was unscrewed from the multi-unit abutments. Any excess acrylic was removed with an acrylic bur (Komet) and polished to high gloss. It is important to note that it is desired to have a convex undersurface of the FP3 provisional restoration for proper tissue healing and cleansabilty.

Figure 15. Mandibular bone foundation guide.

Figure 16. Surgical implant guide.

Figure 17. Insertion of Touareg OS dental implants (Adin Dental Implants).

Figure 18. Mandibular PMMA provisional restoration.

Figure 19. Panorex view of immediate provisionals on dental implants.

In the lower arch, a full-thickness flap was reflected; however, a tooth positioning guide was used to position the bone foundation guide into its accurate position. Using bone screws, the bone foundation guide was then stabilized (Figure 15). At this point, the tooth positioning guide was removed to get full access to the remaining mandibular teeth. Using the Wedge (GoldenDent) instrument, the teeth were loosened, followed by their removal via the Physics Forceps (Directa Dental). Once the teeth were removed, an appropriate alveolectomy was performed, followed by the indexed placement of the surgical implant guide (Figure 16). Again, a fully guided protocol with an appropriate drilling sequence (Adinguide) was used to allow the placement of 6 Touareg OS dental implants. All implants were placed within insertion torque values that ranged from 50 to 70 Ncm (Figure 17). Straight transmucosal abutments were then positioned and tightened to about 25 to 30 Ncm, followed by the placement of the temporary cylinders. Once again, the prosthetic pickup of the provisional restoration was accomplished using Quick Up material (Figure 18). The prosthesis was then removed, contoured, and polished. Soft-tissue closure was accomplished with 4.0 Chromic Gut Sutures (GoldenDent). Once the provisional bridge was secured back onto the multi-unit abutments, any bite adjustments were made with a red diamond football bur (Komet).^7,8 After the patient recovered from anesthesia, an immediate postoperative panoramic x-ray was taken, confirming the position of the dental implants (Figure 19).

Prosthetics

The final restorative phase of treatment was initiated after about 4 to 5 months of healing to ensure full osseointegration of the dental implants. Full-arch impressions were taken using Panasil (Kettenbach LP) polyvinyl siloxane material. Relations were accomplished by taking a bite registration (Futar [Kettenbach LP]) using clear duplicates of the provisional restorations. These impressions and relations, along with digital images of the patient smiling, were forwarded to the dental laboratory (Hybrid Technologies, Orlando) for design in DentalCAD software. Verification jigs (Figure 20) as well as a smile composer were fabricated by this dental laboratory for both the upper and lower arches. When the patient returned several weeks later, the verification jigs were tried in, followed by the smile composers. When the verification jig was inserted, its components were secured with light-cure composite (Grandio Flow [VOCO]) followed by an open-tray impression using Panasil heavy- and light-body material. The smile composers were then inserted so that the patient could see how they looked. Another bite registration was accomplished using Futar Bite Registration with the smile composers (Figure 21). Since the patient was very pleased with the aesthetics of these smile composers, we instructed the dental laboratory to fabricate the definitive restorations. 

Figure 20. Duralay verification jigs.

Figure 21. Futar Bite Registration (Kettenbach LP) with the smile composers.

Figure 22. Zirconia on titanium frame hybrid restorations (Hybrid Technologies).

When providing full-arch, fixed FP3 dental implant restorations, I prefer to utilize a titanium frame with overlying monolithic zirconia and pink porcelain (Figure 22) to replicate the gum tissue. I have personally found that this type of hybrid restoration prevents fractures, chipping, and staining of the teeth because of its zirconia component. In contrast, the titanium component prevents coping dislodgement and distal fracture of cantilevers.^9,10 It is highly suggested that these patients have a nightguard to help with any nighttime grinding or clenching.

Figure 23. Postoperative retracted bite view.

Figure 24. Post-op retracted open bite view.

The definitive titanium hybrid fixed restorations (Hybrid Technologies) were inserted and torqued to the manufacturer’s recommendation of 15 Ncm (Figures 23 and 24). A panoramic x-ray was taken to confirm full seating (Figure 25). Once confirmed, FirstPlug (35 Newtons), a patented medical-grade PTFE material, was placed into the screw channel of the implant restorations, followed by composite material (Wagofil [GoldenDent]).

Figure 25. Post-op panorex x-ray.

Figure 26. Post-op smile view.

The patient, as well as the referring dentist, was very pleased with the final result (Figure 26). Not only were we able to provide an ideal aesthetic outcome, we were also able to provide one that would have a more favorable functional outcome with a good, long-term prognosis. As dentists, our goal is always to save teeth. However, there comes a time or situation where a tooth or teeth is not restorable or does not have a great prognosis, so a dental implant or full-mouth reconstruction with several dental implants is recommended.

REFERENCES

1. Misch CE. The implant quality scale: a clinical assessment of the health-disease continuum. Oral Health. 1998;88(7):15-20, 23-5; quiz 25-6. 

2. Jivraj S, Chee W, Corrado P. Treatment planning of the edentulous maxilla. Br Dent J. 2006;201(5):261-79; quiz 304. doi:10.1038/sj.bdj.4813952 

3. Davarpanah M, Szmukler-Moncler S. Immediate loading of dental implants: Theory and clinical practice. Quintessence International; 2008. 

4. Bedrossian E. Implant treatment planning for the edentulous patient. Mosby; 2008.

5. Romanos GE, Gupta B, Gaertner K, et al. Distal cantilever in full-arch prostheses and immediate loading: a retrospective clinical study. Int J Oral Maxillofac Implants. 2014;29(2):427–31. doi:10.11607/jomi.3243 

6. Vercruyssen M, Laleman I, Jacobs R, et al. Computer-supported implant planning and guided surgery: a narrative review. Clin Oral Implants Res. 2015;26 Suppl 11:69-76. doi:10.1111/clr.12638 

7. Drago C. Frequency and type of prosthetic complications associated with interim, immediately loaded full-arch prostheses: a 2-year retrospective chart review. J Prosthodont. 2016;25(6):433–9. doi:10.1111/jopr.12343 

8. Balshi SF, Allen FD, Wolfinger GJ, et al. A resonance frequency analysis assessment of maxillary and mandibular immediately loaded implants. Int J Oral Maxillofac Implants. 2005;20(4):584–94. 

9. Pozzi A, Tallarico M, Moy PK. Four-implant overdenture fully supported by a CAD-CAM titanium bar: A single-cohort prospective 1-year preliminary study. J Prosthet Dent. 2016;116(4):516–23. doi:10.1016/j.prosdent.2016.03.015

10. Kapos T, Evans C. CAD/CAM technology for implant abutments, crowns, and superstructures. Int J Oral Maxillofac Implants. 2014;29 Suppl:117–36. doi:10.11607/jomi.2014suppl.g2.3 

ABOUT THE AUTHOR

Dr. Nazarian graduated from the University of Detroit Mercy School of Dentistry and completed an AEGD residency from the US Navy in San Diego. In addition, he completed advanced training in dental implants and grafting from the world-renowned Misch International Implant Institute and holds a Diplomate in the International Congress of Oral Implantologists. He teaches other dentists the art and science of dental implants and cosmetics so that his methods can help others outside of his own practice. He has taught non-invasive extractions, grafting, full-mouth rehabilitation, and 3D diagnosis and treatment planning with CBCT. He has been published nationally and internationally in leading dental publications in the areas of cosmetics, metal-free crowns, extractions, grafting, sinus lifts, immediate implant placements, same-day implant provisionalizations, and CAD/CAM restorations. He can be reached at aranazariandds@gmail.com.

Disclosure: Dr. Nazarian reports no disclosures.

A patient enters your practice looking unhappy and says she’s ashamed to smile. Do you immediately ask to see her teeth and possibly comment on them? You have a choice to make. In this author’s opinion, the most important thing to do when a patient enters a practice is to begin creating a relationship with the patient. Experience tells me case acceptance is directly related to knowing the patient’s goals for his or her mouth, building trust with the patient, and helping him or her feel understood.

Background

This patient previously had a full-mouth rehabilitation done elsewhere and said, “I’m unhappy with the way my teeth look” (Figures 1 and 2). I didn’t say “Let me see your teeth,” but rather asked if it would be okay to ask her some questions. Getting permission to ask questions changes the doctor-patient dynamic and levels the playing field between doctor and patient, as if to say to the patient, “We’re in this project together.” The patient begins to know he or she is important, and in the many years I’ve asked that question, I never had a patient reply “No.” I needed to find out what she meant by “unhappy with the way my teeth look” and patiently listened to her answers.  

Figure 1. Preoperative retracted view.

Figure 2a. Pre-op right lateral view. Figure 2b. Pre-op left lateral view.

My questions were not simply “yes” or “no” questions. Instead, they were designed to find out what she liked and disliked about her smile. I also asked her, “How do you think you’d feel if you were happy with your smile?” Notice the key words have to do with emotions. This dialogue with a patient can also create a sense of hope.

 Another important technique in the initial interview is scaling. While it has the same name as the periodontal procedure, it is a way of finding out the strength of the emotions the patient described. I asked, “On a scale of 1 to 10, with 1 being slightly unhappy and 10 being so unhappy with your smile that you cover your mouth or refrain from smiling completely, what number would you give it?” She said “10!” 

I had not examined her yet, and she remarked that she already felt better being in my office. In this author’s opinion, knowing more about a patient as a person, and not simply as a mouth to rehabilitate, is critical. We spoke about her hobbies, her family, where she grew up, etc. She did most of the talking, and I did more of the listening. In a short amount of time, we were able to establish a relationship that led to building trust, an essential ingredient for happy patients and practice growth. Finally, I said, “Let’s take a look at your situation.” 

CASE REPORT

Examination included oral cancer screening, including a VELScope (LED Dental) subsurface tissue survey, TMJ palpation, appropriate x-rays, impressions for diagnostic models with Silganat alginate substitute (Kettenbach LP), and bite registration with O-Bite (DMG America). Models were poured with COECAL stone (GC America) and mounted on a hinge articulator. Existing restorations, periodontal pocket measurements, and restorations I thought she needed for function and appearance were noted in her record. Photographs, including portraits and intraoral images (Figure 3), were made using a Canon/PhotoMed Clinical System (PhotoMed International). 

Figure 3a. Pre-op upper arch occlusal view. Figure 3b. Pre-op lower arch occlusal view.

Prior to our next visit, I had a treatment plan consultation with my laboratory technician.¹ For full-mouth rehabilitation cases, I find it helpful to speak with my technician prior to presenting treatment plans to patients. There can be technical aspects and challenges with the fabrication of restorations I might not see. The goal was to bring the patient back to a healthier state and give her a smile she could enjoy and be proud of. My laboratory was a critical partner in achieving this goal.

At a subsequent visit, we discussed a plan, and all patient questions were answered. She understood that there were some problems that could appear as we moved forward because I couldn’t know what might lay under her existing crowns. The plan included potential root canals, posts, cores, extractions, and implants and a potential sinus lift. Approximate costs were presented only for what I knew I’d have to do. The approximate costs for treatment that could become necessary would be determined sometime in the future. She acknowledged that she understood and looked forward to our next treatment conversation to update her after all her old crowns were removed and her teeth were temporized. 

Treatment Plan

We planned to restore her dentition with PFM crowns and bridges in most areas. A semi-precision interlock between teeth Nos. 5 and 6 was suggested by my lab technician, Steve Killian, CDT (Killian Dental Ceramics, Irvine, Calif). Broken-stress measures serve as “safety valves” against the tremendous leverage forces created by the rigid attachment to 2 or more teeth.^2,3 Further, a rigid connector may not be an ideal choice due to differences in the physiological tooth movement of different teeth. Curvature of the arch, the facio-lingual movement of an anterior tooth, occurs at a considerable angle to the facio-lingual movement of molar teeth. These movements can create stress on the abutments in long-span prostheses. Some means must be used to neutralize the effects of these forces.⁴ 

Lithium disilicate IPS e.max (Ivoclar Vivadent) crowns were planned for the lower incisors. Implants and a fixed bridge in the upper left quadrant were planned using 2 implants and tooth No. 15 as abutments. As we moved forward, we’d find out what else might be needed.

Chairside

All upper restorations were resected with coarse #850-016 Piranha diamonds (SS White Dental) for the porcelain and Great White #2 Gold Series carbides (SS White Dental) for the metal. The existing crowns and bridges were then removed with a Wynman Crown Remover (Integra Miltex). Tooth No. 7 was no longer savable and was extracted. Immediately after extraction, a BioTemps bridge (Glidewell) was relined to fit the preparations and cemented with GC TEMP ADVANTAGE (GC America). A piece of fibrous tissue remained on the buccal of the No. 7 edentulous area several months later. A reduction guide typically used for tooth preparations was created for the excess fibrous tissue and was placed to remove the fibrous tissue with a Microlaser NV (DenMat) (Figures 4 and 5). 

Figure 4. Reduction guide for fibrous tissue removal.

Figure 5. Tissue removed with an NV Laser (DenMat).

The lower arch was treated with PFM bridges in the posteriors. Teeth Nos. 23 to 26 were prepared for the IPS e.max crowns using a Piranha diamond #856-018 (SS White Dental). The closest stump shade was provided to the lab with a photo (Figure 6) so the technician could see any differences between the shade tab and the actual preparations. An impression was made using Identium Medium Body and Light Body (Kettenbach LP). Traxodent (Premier Dental) (Figure 7) retraction paste was used prior to impressioning. The final mandibular full-arch rehabilitation is seen in Figures 8 and 9. 

Figure 6. Ivoclar Stump Shade Guide for IPS e.max restorations (now called IPS Natural Die Material shade guide).

Figure 7. Traxodent (Premier Dental) prior to placing compression caps.

Figure 8. IPS e.max crowns bonded in with Panavia V5 (Kuraray Noritake Dental) immediately postoperatively.

Figure 9. Lower arch rehabilitation post-op.

The upper bridge frame from Nos. 2 to 11 was tried in for fit and occlusal clearance, and the interlock between Nos. 5 and 6 was evaluated (Figure 10). A bite registration was made with O-Bite (DMG America), and a counter lower arch impression was made with StatusBlue (DMG America). 

Figure 10. Try-in of 2-section frame with a semi-precision interlock.

The final upper rehabilitation from Nos. 2 to 11 was inserted with GC Fuji PLUS resin-modified glass ionomer cement (GC America) (Figure 11). A new interim partial with prosthetic teeth on the upper left was inserted to use until implants were placed and ready for restoration in the Nos. 12 and 13 areas. 

Figure 11a. Upper arch ready for implant placement in upper left bicuspid region. Figure 11b. Upper arch rehabilitation prior to implant placement in the Nos. 12 and 13 areas.

Sadly, a few weeks later, the patient fell face-forward, and the blunt force trauma fractured much of the porcelain over the Nos. 6 to 8 area (Figure 12). The patient was told it was improbable that a repair would work due to the seriousness of the fracture. Nevertheless, she asked me to try to fix it. I tried to remove the fractured porcelain and restore it with CLEARFIL Universal Bond Quick (Kuraray Noritake Dental) and CLEARFIL MAJESTY ES-2 composite (Kuraray Noritake Dental). After multiple attempts over several visits, it was clear the patient would need a new bridge from Nos. 6 to 11. Fortunately, the rest of the arch was preserved: The semi-precision interlock saved us. Finally, Nobel Replace Select Implants (Nobel Biocare) were placed in areas of Nos. 12 and 13 and covered to integrate. 

Figure 12a. Blunt force trauma caused major fracture in the porcelain of the Nos. 6-to-11 bridge. Figure 12b. Blunt force trauma caused major fracture in the porcelain of the Nos. 6-to-11 fixed bridge.

Within 3 months, our patient took ill and had an extended hospitalization for several months. During that time, she lost bone around the fully integrated Nos. 12 and 13 implants (Figure 13), leaving some threads on the implants exposed. A second new interim partial made of Lucitone 199 (Dentsply Sirona) and wrought wire clasps was fabricated to fit over the exposed implants and the No. 14 prepped tooth (Figures 14 and 15).

Figure 13. Nobel Biocare implants with healing caps after prolonged medical problems and hospitalization.

Figure 14. Lucitone 199 (Dentsply Sirona) flipper to be worn over healing abutments with exposed threads.

Figure 15. Post-op photo with new interim partial inserted.

An impression was made with Identium Medium and Light Body for a fixed bridge from Nos. 12 to 15 to be supported by 2 implants and a natural tooth. Although this wasn’t my first choice, the situation dictated that this was the best treatment option. The bridge was returned and fitted using Occlude Aerosol Marking Spray (Pascal Company) (Figure 16). Gingival embrasures of the bridge were refined to make them cleansable and polished with Dialite Knife Edged Discs (Brasseler USA) (Figure 17). Waxed dental floss (Oral-B Glide [Procter & Gamble]) loops with slipknots were placed in the embrasures to facilitate cement removal after seating the bridge (Figure 18). It would be easy to open the slipknot with an explorer and then run the floss buccolingually, ensuring no cement was left behind. The bridge from Nos. 12 to 15 was cleaned with a MicroEtcher IIA (Zest Dental Solutions), and the cementation was done with Panavia V5 (Kuraray Noritake Dental). 

Figure 16. Fitting the upper left bridge with Occlude Aerosol Marking Spray (Pascal).

Figure 17. Polishing gingival embrasures with Dialite discs (Brasseler USA).

Figure 18. Slipknot loops to facilitate embrasure cement cleanup.

Figure 19. Final post-op photo.

Tooth vs Tooth and Implant-Supported Bridge

There has been much discussion and no consensus about cementing fixed bridges that are tooth- and implant-supported. Frank Spear said that whether or not it is acceptable to connect an implant to a tooth or teeth in a restoration is one of the most misunderstood areas of implant dentistry. The reason so much confusion exists is simple: There isn’t one correct answer. With the risks of overloading the implant and intrusion of the teeth, it would seem reasonable to ask why you would want to connect an implant and a tooth, but there are times when it may be necessary and sometimes even desirable.⁵ Al-Omiri et al⁶ concluded that further long-term randomized clinical studies with large sample sizes are required to determine the viability of this treatment paradigm. In this author’s opinion, for this case, in the upper left posterior quadrant, combining 2 implant abutments with one natural tooth abutment was indicated.

CONCLUSION

Dentists and their teams have the power to change a person’s life, whether with appearance-related procedures, by restoring function, or with a combination of both. So long as a patient doesn’t have pain, swelling, or bleeding, I believe it’s important to talk with him or her about his or her goals for oral health and appearance, ie, his or her smile. Sometimes achieving the desired results is a smooth and short journey; other times, it’s long with unexpected challenges along the way. As the Beatles song title says, it can be a “long and winding road.” And when doing a full-mouth rehabilitation, we ought to keep the words of the dental icon Dr. Peter Dawson in mind. He said the longest distance between 2 points is a shortcut.⁷ 

This patient came in excitedly for a final visit that she called her “dental photo shoot.” She reported everything in her mouth felt fine and that she could smile and eat without hesitation. The final photo (Figure 19) shows how much the treatment meant to her. Much has been written about a smile. “Everyone smiles in the same language” has been attributed to the famous comedian, George Carlin. Mother Teresa said “Peace begins with a smile.” The Broadway hit musical Annie has a famous song titled “You’re Never Fully Dressed Without a Smile.”

At our final visit, I asked this patient to tell me what it meant to her to have her smile changed and give her what she once had. She told me, “All the work we put in to change my smile was life-changing. When I used to hide my smile for many, many years, I didn’t realize how debilitating that was. Today I smile with courage—I am encouraged. There’s nothing that stops me anymore because of my smile.” I concluded by asking her if her new smile was infectious. She replied, “That’s what I’m told.”

ACKNOWLEDGMENT

The author extends his heartfelt thanks to the late Stephen Killian, CDT; John Hunzicker; and the entire team at Spectrum Killian Dental Ceramics in Irvine, Calif. 

REFERENCES

1. Fier MA. Patient-centered treatment planning: part 1. Dent Today. 2007;26:56-61.

2. Markley MR. Broken-stress principle and design in fixed bridge prosthesis. J Prosthet Dent. 1951;1(4):416-23. doi:10.1016/0022-3913(51)90027-3 

3. Sivakumar S. Management of partial edentulism using nonrigid connectors as a treatment modality: a case report. Cureus. 2020;12(4):e7790. doi:10.7759/cureus.7790

4. Yaqoob A, Rasheed N, Ashraf J, et al. Nonrigid semi-precision connectors for FPD. Dent Med Res. 2014;2:17-21.

5. Spear F. Connecting teeth and implants: Yes, no, maybe? Spear Education. 2018. 

6. Al-Omiri MK, Al-Masri M, Alhijawi MM, Lynch E. Combined implant and tooth support: an up-to-date comprehensive overview. Int J Dent. 2017;2017:6024565. doi:10.1155/2017/6024565

7. Hedlund A. How to avoid mistakes during treatment planning. Dawson Academy Whitepaper. 2014.

ABOUT THE AUTHOR

Dr. Fier is a practicing clinician and a clinical associate professor at the Touro College of Dental Medicine. He is the executive vice president of the American Society for Dental Aesthetics. He teaches continuing education courses nationally and internationally at dental schools, major conventions, and study clubs. Dr. Fier is a Diplomate of the American Board of Aesthetic Dentistry, a Fellow of the American College of Dentists, the International College of Dentists, and the Academy of Dentistry International.  He can be reached at (845) 354-4300 or via email at docmarv@optonline.net or marvin.fier@touro.edu.

Disclosure: Dr. Fier receives lecture support from some of the companies mentioned in this article. 

In today’s economy, we have seen dramatic changes in lifestyle, health, and income. Because of this, we have seen patients delay dental treatment until it finally becomes very painful. Although patients may want full-mouth dental implant reconstructions with fixed restorations, this may not always be something that fits into their budgets. As dental providers, we need to offer our patients a variety of different treatment options in order to restore their dentition to proper form and function. This article focuses on the steps involved in providing denture and overdenture treatment, in addition to extractions, grafting, and dental implant placement.

CASE REPORT
Diagnosis and Treatment Planning
A patient presented to my practice for a consultation, wanting to restore his smile. He complained of generalized discomfort in his teeth due to the caries and periodontal disease that were readily apparent (Figures 1 and 2). Previously, the patient had teeth removed one at a time when there was severe pain or infection. However, this time he wanted to have a “game plan” and be proactive in any suggested treatment that would fit into his budget. He had already been informed by a few dental providers that he would probably need all his remaining teeth removed due to his advanced periodontal disease, so he was aware that this might be the case.

Figure 1. Retracted, preoperative smile view.	Figure 2. Retracted, pre-op frontal view.
Figure 3. A CBCT scan was taken (CS 8100 3D [Carestream Dental]).	Figure 4. Pre-op centric occlusion bite registration (Futar [Kettenbach LP]).
Figure 5. Immediate dentures.	Figure 6. Physics Forceps (GoldenDent) were used for extractions.
Figure 7. The area, grafted and sutured.	Figure 8. Try-in of the immediate denture.
Figure 9. Chairside soft denture reline material (Sofreliner Tough [Tokuyama Dental America]).	Figure 10. Dispensing Sofreliner Tough into the immediate denture.

At the consultation appointment, the patient was informed that we would require a CBCT scan to assist us in accurately diagnosing his dental conditions (Figure 3). Using the CS 8100 3D (Carestream Dental), a CBCT scan was taken so that we would be able to identify the areas of infection and decay and also the areas of remaining bone for dental implant placement. Since the patient had expressed his concern about cost, our goal was to not only find a treatment modality that would restore aesthetics and function economically but also provide a treatment that could potentially be upgraded in the future.

Preliminary impressions for immediate dentures were obtained using Silginat (Kettenbach LP), a cost-effective, elastomeric polyvinyl siloxane (PVS) impression material. Orthodontic retractors were utilized to verify that the patient was accurately biting in centric occlusion (CO) into the fast-setting bite registration material (Futar [Kettenbach LP]) (Figure 4). Photographs of the patient’s smile and midline were acquired in order to properly inform the dental laboratory team of any changes that were desired, including tooth position, tooth size, and arch form, for the immediate dentures (Figure 5).

All risks, benefits, and alternatives were fully described to the patient and any questions fully answered. Upon listening to the various treatment options, the patient decided to have all his remaining teeth extracted and those sites grafted. In the upper arch, the patient would be getting a complete denture, whereas in the lower arch, he would be getting an overdenture retained by 4 dental implants.

In order to assist the patient with this investment, financing options using a third-party payment option (Alphaeon Credit) were discussed. This consideration was a very important part of facilitating acceptance of his care since it made the cost of treatment more economical.

Clinical Protocol
After local anesthesia was administered, we started removing the teeth in the maxillary arch (Physics Forceps [GoldenDent]) (Figure 6). Since the Physics Forceps act like a Class I lever, the only force applied with the beak is on the lingual aspect of the tooth. With the beak positioned at the lingual cervical portion, the soft bumper is placed on the buccal alveolar ridge at the approximate location of the muco-gingival junction. While the beak grasps the tooth, the bumper acts as the fulcrum, providing leverage and stability for the beak. Extraction is accomplished with slight wrist movement rotation in the buccal direction for about 30 to 60 seconds, depending on the length and curvature of the roots.

Once the teeth in the maxillary arch were removed, any granulation tissue remaining within the sockets was removed using a curette (GoldenDent), and any sharp areas of the alveolar crest were leveled with a bone bur (GoldenDent). OsteoGen Bone Grafting Plugs (IMPLADENT LTD) were then placed in each socket to facilitate bone growth within the sockets over a 4- to 5-month period for future implant placement if the patient desired. Using resorbable sutures, the OsteoGen Bone Grafting Plugs were further stabilized, and the tissue was sutured (Figure 7).

The immediate maxillary denture was tried in to confirm a passive placement, and the patient’s midline was also confirmed (Figure 8). Next, the immediate denture was fully seated with a self-cured, silicone-based soft reline material (Sofreliner Tough Medium [Tokuyama Dental America]) (Figures 9 and 10). According to the manufacturer, Sofreliner Tough is designed to provide long-lasting and consistent relief with outstanding durability for up to 2 years. This reline material is also claimed to have excellent stain and odor resistance and excellent adhesion to denture base materials.

Using the same forceps and atraumatic technique as with the upper arch, the remaining lower teeth were extracted (Figure 10). The remaining sockets were curetted to further remove any debris or granulation tissue (Figure 11). Once cleaned out, the bone leveling guide was positioned over the mandibular ridge (Figure 12). This bone leveling guide was then used as a reduction guide to eliminate any undercuts while creating a leveled area with sufficient width for dental implant placement (Figure 13). Once the ridge was completely leveled to the height of this guide, the implant surgical guide was secured into place (Figure 14). Using the MGuide set (MIS Implants Technologies), the drilling sequence for 4 Seven (MIS Implants Technologies) dental implants was initiated. This computer-based planning system enhances both accuracy and effectiveness for a more ideal implant placement procedure. The drills in the MGuide kit are designed with built-in stoppers to allow precision preparation and placement to the planned depth and positions without the need of keys.

Figure 11. The lower teeth were removed using the same forceps and extraction technique as with the maxillary extractions.	Figure 12. The remaining ridge after tooth removal.
Figure 13. Leveling bone using a CBCT-based guide.	Figure 14. Positioning the implant surgical guide.
Figure 15. A 3.75- × 13-mm Seven (MIS Implants Technologies) dental implant.	Figure 16. Overdenture attachments were inserted, followed by graft material.
Figure 17. Overdenture housings ready for pickup.	Figure 18. Chairside hard denture reline material kit (Rebase II [Tokuyama Dental America]).
Figure 19. Immediate postoperative retracted view.	Figure 20. Retracted, post-op smile view.

The four 3.75- × 13-mm Seven dental implants (Figure 15) were torqued down to the desired depth at approximately 50 Ncm. Next, 5.0-mm (in height) LOCATORs (Zest Dental Solutions) were inserted within the implants using the provided Zest tool. Using a torque wrench with the appropriate adapter, the LOCATORs were tightened to 30 Ncm (Figure 16). Now that the internal aspects of the dental implants were sealed, bone grafting putty material (GoldenDent) was injected into any remaining voids in the bone (Figure 17). Using resorbable sutures, primary closure was accomplished around the locations of the implants. In order to avoid tearing the sutures during the pickup procedure of the Zest housings, small strips of C-fold towel were used to cover any exposed areas of the sutures.

Since the bone had been leveled with the guide, there was no interference detected between the denture base and attachments in the anterior portion of the immediate denture. Using Rebase II chairside hard denture reline (Tokuyama Dental America) (Figure 18), the female components of the LOCATORs were then picked up. Since this material is methyl methacrylate-free, it doesn’t have a strong odor or taste. In addition, it generates very minimal heat while setting.

The first step in the pickup process was to brush a thin coat of Rebase II adhesive (included in the Rebase II Kit [Tokuyama Dental America]) into the area of the overdenture attachments. This is done to enhance the chemical retention between the denture base and the hard reline/pickup material. KY lubricant was then applied to the surrounding surfaces of the denture to prevent unwanted adherence of excess material. Once the powder and liquid of the Rebase II material were mixed, the material was then placed into a plastic dispensing syringe and injected into the internal anterior portion of the lower immediate denture as well as onto the receptor attachments.

The prosthesis was held in position by the patient biting together in CO (Figure 19). After approximately 3 minutes, the overdenture with the incorporated retention caps was removed, and any excess material was removed with a trimming bur. The bite of the upper immediate denture with soft reline opposing the lower overdenture was verified, and any interferences were eliminated (Figure 20).

CLOSING COMMENTS
As we see more and more patients presenting with dental issues who require full-mouth extractions, we need to offer a variety of different treatment modalities to accommodate their aesthetic and functional needs. These treatment options also need to take their budgets into consideration. Overdentures are a great treatment option for these patients, which can later be upgraded to fixed restorations with additional dental implant therapy.

Dr. Nazarian maintains a private practice in Troy, Mich, with an emphasis on comprehensive and restorative care. He is a Diplomate of the International Congress of Oral Implantologists. He has conducted lectures and hands-on workshops on aesthetic materials, grafting, and dental implants throughout the United States, Europe, New Zealand, and Australia. He can be reached via email at aranazariandds@gmail.com.

Disclosure: Dr. Nazarian reports no disclosures.

Related Articles

Focus On: Case Acceptance

Prosthetic-Driven Treatment Plan: Thoughtful Choices Ensure Optimal Results

Integrating a Systematic Digital Workflow

INTRODUCTION
The fixed full-arch implant restoration is among the most rewarding types of treatments in dentistry. The clinician is able to provide patients who present with terminal dentition or unstable dentures a fixed solution with the same function, stability, and aesthetics of natural dentition.¹ In addition to replacing the patient’s teeth, this implant solution dramatically improves patient comfort, self-confidence, and quality of life.²

Clinicians who provide this service for their patients have commonly encountered a complex clinical procedure requiring numerous appointments and considerable chair time in order to produce the optimal prosthetic design. This clinical inefficiency is caused by many factors, including difficulties in capturing an accurate impression, visualizing where the teeth should be positioned within the restorative space, and correctly recording the jaw relationship of the patient. However, by making full use of the traditional tools and methods and taking advantage of modern innovations like the CAD/CAM provisional implant prosthesis, we can simplify the process, save valuable chair time, and produce a more predictable outcome. Investing more time in properly completing the steps at the beginning of the restorative process can save substantial time in subsequent appointments and result in a more accurate and efficient clinical workflow. There are several key elements of restoration fabrication that can help streamline the process:

• Place multi-unit abutments to correct angulation issues and establish a level restorative platform around the arch. This eases the seating and removal of try-in appliances as well as the restoration.
• Capture the precise position of the implants and how they relate to the positioning of the other implants around the arch. This can be accomplished through the use of an implant verification jig and custom impression tray.
• Determine the correct positioning of the prosthetic teeth in space. This places special importance on taking the time to make all necessary adjustments to the wax rim.
• During the wax rim appointment, accurately record the relationship of the upper arch and the lower arch.
• Provide a provisional implant prosthesis so the patient has a chance to confirm his or her satisfaction with the function, phonetics, and aesthetics of the prosthesis during his or her daily activities before the final restoration is produced.

The following case example illustrates a streamlined clinical workflow for producing a full-arch implant restoration, including the tools, steps, and techniques that can be used at each appointment to achieve a predictable final result. While this process was used to produce a monolithic zirconia implant prosthesis, it can be followed to achieve optimal results for any screw-retained full-arch restoration.

CASE REPORT
Appointment 1: Preliminary Impressions
The patient presented with an immediate healing denture over implants placed by another clinician (Figure 1). Desiring maximum function and stability, he had requested a fixed prosthesis for the implant restoration. An assessment of the restorative space determined that there was sufficient room for a fixed full-arch monolithic zirconia implant restoration, which requires a minimum of 8.0 mm of vertical height. A BruxZir Implant Prosthesis (Glidewell) was selected due the strength and durability of solid zirconia, which has been shown to be remarkably durable in full-arch indications.^3,4 Note that zirconia is also an optimal material to use in situations of limited restorative space since less vertical height is required in comparison to the screw-retained hybrid denture. Furthermore, with the use of aesthetic zirconia in full-arch indications, we can achieve a beautiful outcome that compares favorably to layered or hybrid prostheses, with a far lower risk of chipping and fractures.

Figure 2. A preliminary open-tray impression was made to begin the restorative process. Shown here, the impression tray was tried in to ensure the transfer copings emerged through the holes that were cut in the tray chairside.

Figure 3. A duplicate of the patient’s existing denture was made using a denture duplicating flask. Providing this to the lab is one of the methods that will help ensure that the prosthetic teeth are correctly positioned in space from the very beginning. Furthermore, this provides the clinician with an opportunity to communicate preferences to the dental lab with regard to the patient’s existing appliance.

To begin the restorative process, an open-tray, preliminary full-arch impression was taken at the implant level, and an impression of the opposing arch was also taken (Figure 2). Next, a duplicate of the patient’s existing prosthesis was made to aid the lab in the design of the wax rim (Figure 3). This is an underutilized method that can help streamline the restorative process and give the dental lab a better idea of where the teeth should be situated to guide the creation of the wax rim and help determine the positions of the midline and incisal edges.

The preliminary impression and duplicate denture were sent to the lab team along with clinical smile photos. Providing images of the patient’s smile with his or her existing prosthesis in place is invaluable in communicating the desired aesthetics or any changes to the patient’s denture to the lab team and will also help to save time in the appointments that follow.

Figure 4. A combination of straight and angled multi-unit abutments were connected to the implants to create a uniform restorative platform around the arch. The use of multi-unit abutments helps ensure a smooth, efficient restorative process that minimizes patient discomfort, eases the seating of try-ins, and saves time at future appointments.	Figure 5. The individual sections of the implant verification jig (IVJ) provided by the lab were connected to the implants. Then the IVJ was luted together using Camouflage Nanohybrid Composite (Glidewell). By precisely capturing the inter-implant positions in the final impression, the IVJ ensures that an accurate master cast is produced and a passive fit is achieved for the restoration.
Figure 6. A custom tray fabricated and provided by the lab team was used, capturing the IVJ and the relative positions of the implants in the final impression.	Figure 7. The wax rim was tried in. After careful evaluation, adjustments were made to fine-tune tooth position, incisal edges, the midline, and other important aspects of the restoration design. Shown here, the vertical dimension of occlusion was taken using a digital caliper, which offers a precise means of recording this measurement.

Appointment 2: Verified Final Impression, Wax Rim, and Jaw Relationship Records
To begin the second appointment, multi-unit abutments that were selected and provided by the dental laboratory were connected to each implant (Figure 4). This improved the angulation of the posterior implants and brought the restorative platform of each implant equigingival. Multi-unit abutments are essential in ensuring a smooth restorative procedure and predictable outcome. By raising and creating a level restorative platform, multi-unit abutments simplify each subsequent step. It’s easier, less time-consuming, and more comfortable for the patient when seating the wax rim, setup, provisional, and final restoration. In addition, multi-unit abutments help protect the implant-bone junction because the tissue is not disturbed during try-ins and subsequent visits.

Taking a verified final impression is another key step in ensuring a streamlined clinical workflow. Verifying the positions of the implants in relation to one another is crucial in achieving a passive fit of the wax setup try-in as well as the eventual restoration. For this reason, an implant verification jig, fabricated and provided by the lab team, was connected to the multi-unit abutments and splinted together. This ensured a precise representation of the implant positions in the final impression (Figure 5). Then a custom tray, which helps minimize distortion of the impression material, was used to make the final impression (Figure 6). Because the implant verification jig was picked up in the final impression, the lab team was able to create a highly accurate master cast.

Figure 8. After working with the patient to properly place his jaws in centric relation, care was exercised to record an accurate bite registration. By performing this step correctly, the likelihood of occlusal errors arising later in the process is reduced.

Figure 10. The bite should be confirmed at the wax setup appointment as it’s easier and more efficient to make any occlusal adjustments before the CAD design for the restoration is created.

When trying in and adjusting the wax rim, it’s important to contour the rim to accurately represent the final positioning of the teeth. In this case, because a duplicate of the patient’s existing denture was made along with the preliminary impressions, the laboratory technician was better able to pre-contour the wax rim and establish the positioning of the teeth. At the chair, adjustments were made to fine-tune the teeth positioning and other aspects of the prosthetic design represented by the wax rim. At this appointment, it’s vital to confirm and make any necessary alterations to the key elements of the restoration design, including midline, incisal edge position, lip support, the smile line/occlusal plane, vertical dimension of occlusion (VDO), and phonetics (Figure 7). Note that engaging fewer of the implants eases the removal and reseating of the wax rim as you evaluate and adjust the wax rim.

Capturing an accurate bite is essential to eliminate the need for wax reset appointments. After fully contouring the wax rim and measuring the VDO, we practiced putting the patient into centric relation and having him hold that position. Then, with the patient in centric relation, bite registration material was injected (Figure 8). By taking the time to correctly record the jaw relationship, any significant occlusal issues were avoided in subsequent appointments.

Figure 11. A provisional implant prosthesis fabricated from the CAD design for the restoration was provided by Glidewell. This afforded an additional opportunity to verify the prosthetic design and to fine-tune the occlusion.

Figure 12. Profile view of the provisional implant prosthesis in place. Due to the precision of the CAD/CAM process, the aesthetics, function, and phonetics of the provisional perfectly mimicked that of the approved wax setup. The patient wore the provisional for 3 weeks and confirmed that he was satisfied with the restoration design.

Figure 13. The final BruxZir Implant Prosthesis was delivered. It met the expectations of the patient due to the trial period spent with the provisional in place. The patient was thrilled with the lifelike aesthetics of the prosthesis. By taking great care in executing the recommended steps toward the beginning of the restorative process, each subsequent appointment required less chair time, wax resets were avoided, and the restoration was created following a smooth and efficient clinical workflow.

Appointment 3: Wax Setup Try-In
By following the steps outlined in the previous appointments, the wax setup provided by the lab was accurate and required only simple adjustments. After confirming that the wax setup seated passively, the aesthetics and phonetics were confirmed (Figure 9). Then the patient’s bite was checked (Figure 10). With the midline, occlusal plane, lip support, VDO, and other prosthetic design aspects finalized, the case was returned to the dental laboratory. Upon receipt of the approved wax setup, the lab team scanned the master cast and wax setup and created the CAD design for the monolithic zirconia implant prosthesis. The lab team then fabricated a provisional implant prosthesis that precisely replicated the approved wax try-in, affording the opportunity to confirm the design one last time before the restoration was milled from the BruxZir Esthetic Zirconia (Glidewell).

Appointment 4: CAD/CAM Provisional Implant Prosthesis
The provisional implant prosthesis allowed the patient to “test drive” the restoration. Patients appreciate the opportunity to go home and show their families how the restorations look, test their function, and verify comfort during speaking and eating (Figure 11). In this case, the provisional fit well and required only minor occlusal adjustments (Figure 12). Hygiene instructions were communicated to the patient so he could verify that the restoration could be cleaned properly.

Appointment 5: Delivery of the Final Restoration
After the patient wore the provisional implant prosthesis for 3 weeks, he confirmed that he was happy with the design and ready for the final restoration. The provisional was returned to the dental laboratory so that the minor occlusal adjustments could be implemented in the final CAD design. The final prosthesis was milled from a block of monolithic zirconia, without the need for veneering material, offering maximal resistance to wear, chipping, and fractures. The final restoration was delivered without any complications (Figure 13). Having grown accustomed to the provisional, the patient was extremely happy with the final zirconia restoration.

CLOSING COMMENTS
Although restoring a fixed full-arch implant case can be challenging, by taking the necessary steps, using the proper tools, and investing the necessary amount of time and care during the initial appointments, a smooth, predictable outcome is well within the reach of any dentist who has an understanding of basic denture techniques. Furthermore, with the advent of the digitally fabricated provisional and the monolithic zirconia implant restoration, a beautiful, long-lasting result can be achieved with a great deal of confidence. With growing numbers of edentulous patients requesting the comfort and function of a fixed implant prosthesis, clinicians have every reason to familiarize themselves with a streamlined, reliable clinical workflow for this state-of-the-art restoration.

References

1. Brennan M, Houston F, O’Sullivan M, et al. Patient satisfaction and oral health-related quality of life outcomes of implant overdentures and fixed complete dentures. Int J Oral Maxillofac Implants. 2010;25:791-800.
2. Preciado A, Del Río J, Lynch CD, et al. Impact of various screwed implant prostheses on oral health-related quality of life as measured with the QoLIP-10 and OHIP-14 scales: a cross-sectional study. J Dent. 2013;41:1196-1207.
3. Carames J, Tovar Suinaga L, Yu YC, et al. Clinical advantages and limitations of monolithic zirconia restorations full arch implant supported reconstruction: case series. Int J Dent. 2015;2015:392496.
4. Pozzi A, Holst S, Fabbri G, et al. Clinical reliability of CAD/CAM cross-arch zirconia bridges on immediately loaded implants placed with computer-assisted/template-guided surgery: a retrospective study with a follow-up between 3 and 5 years. Clin Implant Dent Relat Res. 2015;17(suppl 1):e86-e96.

Dr. Manalili received her DDS degree from the Stony Brook University School of Dental Medicine, where she won the Hanau Best of the Best: Excellence in Prosthodontic award. She earned an advanced education specialty certificate in postgraduate prosthodontics before joining Glidewell in 2018. As the director of clinical prosthodontics at Glidewell, she conducts clinical research and performs advanced surgical and restorative procedures. She is also a Fellow of the International Congress of Oral Implantologists and has a passion for a restorative-driven approach to implant placement. She can be reached at taylor.manalili@glidewelldental.com.

Disclosure: Dr. Manalili is a member of the clinical R&D team at Glidewell and received compensation for writing this article.

Related Articles

Full-Arch Implant Surgical and Restorative Considerations: Innovative Digital Workflow Using a Verification Jig With Teeth

Full-Arch Implant Surgical and Restorative Considerations: Utilizing a Full Template Guidance Technique

Full-Arch Zirconia Screw-Retained Prosthesis

Mandibular overdentures are soft-tissue or implant-retained, depending on the number of implants employed. Support, stability, and retention are obtained via natural anatomy, retentive features of the prosthetic components, denture design, and occlusal factors. Treatment plans within the overdenture concept include 2 to 5 implants, placed within the mental foramens corresponding to 5 columns (A, B, C, D, and E) of bone.³ The number of implants utilized dictates the position and whether a superstructure or solitary abutments are used. Research supports 2 independent solitary abutments placed in the B and D positions to retain a soft-tissue-supported overdenture. A 2-implant overdenture is superior in stability, support, and retention compared to a conventional complete denture.^4,5

CASE REPORT
Diagnosis and Treatment Planning
A 71-year-old female presented with an interest in dental implants. Her chief complaint was “Take these dentures and throw them in the garbage. I want to eat pecans and corn on the cob.” Her dental history included the use of maxillary and mandibular dentures for 3 years. The diagnostic appointment included an intraoral examination, diagnostic models, photographs, and a panoramic radiograph (Figures 1 to 3). The medical history indicated she had diabetes mellitus and hypertension. Her A1C value was 5.5. The daily medications reported were 81 mg ASA and 100 mg Losartan. Aesthetics, support, stability, retention, and vertical dimension of occlusion of the existing prothesis were evaluated (Figure 4).

Figure 1. Mandible (edentulous ridge).	Figure 2. Maxilla (edentulous ridge).
Figure 3. Panoramic radiograph.	Figure 4. Complete denture (frontal view).

The consultation included a discussion of treatment alternatives, including overdentures, fixed detachable restorations, and abutment/ceramic metal restorations. Consent was reviewed and signed with an emphasis on proximity of the mandibular nerve, altered sensation, and paresthesia. Treatment time, fees, and financial options were given. The patient chose a maxillary denture reline and a 2-implant mandibular overdenture.

A cone beam computed tomography (CBCT) scan was taken with a radiographic marker guide (Figure 5). Prior to surgery, the CBCT scan was analyzed for implant selection, anatomical features, and abnormalities, and specific attention was given to the location of the mental nerve (Figures 6 and 7). The radiographic guide was modified into a surgical template, depicting implant placement in the mesial-distal dimension.

Clinical Protocol
The patient was prepped, draped, and asked to rinse with a chlorhexidine mouth rinse (Peridex [3M]) for 30 seconds. Infiltration anesthesia was administrated in the buccal/lingual mucosa, consisting of 2 carpules (36 mg) and 2% lidocaine (1:100,000 epinephrine) and 1 carpule (18 mg) and 4% septocaine (1:100,000 epinephrine).

The surgical guide was placed, and then bleeding points were established through the mucosa, utilizing an endodontic explorer and a No. 4 round bur to create a “dimple” on the ridge. A full mucoperiosteal flap was made with a 15-c blade and reflected with a periosteal elevator to expose the ridge. The osteotomy was developed utilizing 1.3-, 2.3-, and 2.8-mm drills to a depth of 13.0 mm. Implant placement was completed by using a fixation mount, 2.5-mm hex tool, and ratchet. Two implants were placed (3.7 x 13 mm Legacy1 [Implant Direct]) with two 3.7- x 3.0-mm titanium healing collars. The flap was closed with 4.0 vicryl sutures using a dual-closure technique, consisting of a horizontal mattress and an interrupted manner. A panoramic radiograph, postoperative instructions, and a soft reline of the mandibular denture completed the procedure (Figure 8).

After 3 months, the healing collars were removed utilizing a 1.25 hex tool, and the gingival sulcus was measured with a periodontal probe (Figure 9). The appropriate abutments (LOCATOR R-Tx Removable Attachment System [Zest Dental Solutions]) were selected and torqued (30 Ncm) into place (Figure 10). Next, 2 impression copings were placed (Figure 11). The existing denture was relieved in the area of the LOCATOR R-Tx abutments and roughened in the area of the reline. A quality vinyl polysiloxane impression material (Imprint III VPS Impression Material [3M]) was utilized to capture the anatomy, peripheral borders, and impression copings. A 3.35-mm abutment analogue was inserted into the impression copings.

The dental laboratory team performed the reline aspect for the maxillary denture and mandibular overdenture and the incorporation of the attachment processing assembly into the denture base.

Figure 5. CBCT 3-D view.	Figure 6. CBCT sagittal view, right.
Figure 7. CBCT sagittal view, left.	Figure 8. Panoramic radiograph of two 3.7 x 13 mm Legacy1 implants (Implant Direct).

The maxillary denture and mandibular 2-implant overdenture were placed with a medium retention (blue) insert (Zest Dental Solutions) (Figure 12). The occlusion was modified to reflect a bilateral, balanced, lingualized occlusion (Figure 13). The patient was scheduled in 3 days for a post-insertion evaluation. After 3 days, minor occlusal and mucosal adjustments were made. The patient expressed that the retention was “great.”

DISCUSSION
The mandibular edentulous patient has served as the impetus for the emergence of research in the field of oral implantology.⁶ The conventional mandibular full-denture patient experiences poor stability, support, and retention in regard to prosthetic principles. Patient limitations include mastication deficiency, occlusal disharmony, lack of confidence, compromised aesthetics, and chronic ulcerations. The overdenture maintains bone and retards bone-resorptive processes. The mandibular overdenture is a cost-effective, predictable prosthesis with successful long-term outcomes.⁷

A diagnosis based on sound clinical and radiological evidence is critical. A clinical exam including palpation of the ridge for undercuts, visualization of keratinized gingiva, and the location of muscle attachments is also important. A CBCT radiograph aids in implant selection, 3-D anatomy, bone abnormalities, and the location of vital structures (mylohyoid undercuts, inferior alveolar nerves).

Infiltration anesthesia is utilized to enhance patient awareness during osteotomy preparation if it’s in close proximity to the mental foramen or if an anterior loop is encountered. A single-stage surgical approach was utilized because the implants were placed in healed sites with an adequate zone of keratinized tissue. The implant placement was designed in the BD position, maximizing anterior-posterior spread.⁸ A torque value was measured to be greater than 35 Ncm via a calibrated torque wrench.

Figure 9. Healing collars at 2 weeks post-surgery.	Figure 10. Abutments (LOCATOR R-Tx Removable Attachment System [Zest Dental Solutions]).
Figure 11. Impression transfer copings in place.	Figure 12. Intaglio surface of the mandibular overdenture with the medium (blue) retention inserts in place.

Figure 13. Maxillary denture/mandibular

The prosthetic approach was based on an evaluation of the existing prosthesis. Phonetics were evaluated by fricative, repose, and sibilant sounds. Aesthetic assessment included incisal edge position, tooth shape, length, width, and pronunciation of the “E” sound. Vertical dimension of occlusion and occlusal principles were evaluated.⁹ The patient approved the aesthetics, phonetics, and occlusion of the existing prosthesis.

After an evaluation, a decision was determined to convert the existing mandibular denture into a 2-implant overdenture.10 This approach should only be used when a denture meets the standard of care of conventional denture prosthetics. As a result, the utilization of an existing denture prosthesis is a limited occurrence. If a new overdenture is fabricated, then a custom tray is used to pick up the impression copings secured to the LOCATOR R-Tx abutments. A unibase is incorporated with denture attachment housings and black processing inserts. A wax bite rim is made to capture a maxillary/mandibular relationship. A denture tooth try-in is followed by final overdenture placement. A well-fitting denture with excellent support and stability, with the aid of implants to maximize retention, improves the clinical outcome.

The prosthetic retentive feature options for implant overdentures can be superstructure bars with retentive attachments or solitary abutments.¹⁰ If 2 implants are utilized, solitary abutments are the prosthetic treatment plan of choice. The LOCATOR R-Tx Removable Attachment System is a technological advancement over earlier design renditions. The innovative design is inclusive of a tapered, narrow geometric platform that enhances the path of insertion. It provides improved path of insertion when multiple implants with various angles of divergence are encountered. This design may reduce the need for the fabrication of a superstructure. The inserts are designed with horizontal grooves and flats to resist vertical and rotational movement. The insert coating material fabricated in TI Carbon nitrate demonstrates better wear resistance. The pink-colored anodization provides a better aesthetic appearance and prevents metal shine-through. A variety of retention inserts allows the management of prosthesis retention and customizes a patient’s level of manual dexterity.

The enhanced design minimizes complications and concerns about past abutments. The internal aspect of the LOCATOR legacy type has the potential to collect plaque and food debris, preventing seating of the male component. The new design contains a small internal aspect for the torque-hex aspect and lowers the potential of food collection. The torque value achieved on the LOCATOR is accomplished with a hex tool and torque wrench vs the tri-lobe design.

CLOSING COMMENTS
The population of the world is aging, and the number of edentulous patients are coincident with this statistic.¹¹ Implant overdentures are an effective, evidence-based modality with proven successful clinical outcomes. Mandibular overdentures demonstrate high success votes within the various treatment plan alternatives. The utilization of solitary abutments is the most common prosthetic approach for the 2-implant approach. It is critical to include overdentures and fixed, detachable, and traditional abutment ceramo-metal restorative options as treatment options for our edentulous patients.

References

1. Misch CE. Treatment options for mandibular implant overdenture: An organized approach. In: Misch CE, ed. Contemporary Implant Dentistry. St. Louis, MO: Mosby; 1993:223-240.
2. Feine JS, Carlsson GE, Awad MA, et al. The McGill consensus statement on overdentures. Mandibular two-implant overdentures as first choice standard of care for edentulous patients. Gerodontology. 2002;19:3-4.
3. Jemt T, Chai J, Harnett J, et al. A 5-year prospective multicenter follow-up report on overdentures supported by osseointegrated implants. Int J Oral Maxillofac Implants. 1996;11:291-298.
4. Rashid F, Awad MA, Thomason JM, et al. The effectiveness of 2-implant overdentures—a pragmatic international multicentre study. J Oral Rehabil. 2011;38:176-184.
5. Raghoebar GM, Meijer HJ, van’t Hof M, et al. A randomized prospective clinical trial on the effectiveness of three treatment modalities for patients with lower denture problems. A 10-year follow-up study on patient satisfaction. Int J Oral Maxillofac Surg. 2003;32:498-503.
6. Albrektsson T, Brånemark P-I, Hansson HA, et al. Osseointegrated titanium implants. Requirements for ensuring a long-lasting, direct bone-to-implant anchorage in man. Acta Orthop Scand. 1981;52:155-170.
7. Vogel RC. Implant overdentures: a new standard of care for edentulous patients—current concepts and techniques. Compend Contin Educ Dent. 2008;29:270-276.
8. English CE. Critical A-P spread. Implant Soc. 1990;1:2-3.
9. Payne SH. A posterior set-up to meet individual requirements. Dent Dig. 1941;47:20-22.
10. Naert I, Gizani S, Vuylsteke M, et al. A 5-year prospective randomized clinical trial on the influence of splinted and unsplinted oral implants retaining a mandibular overdenture: prosthetic aspects and patient satisfaction. J Oral Rehabil. 1999;26:195-202.
11. He W, Goodkind D, Kowal P. An Aging World: 2015. Washington, DC: US Census Bureau; 2016. https://www.census.gov/content/dam/Census/library/publications/2016/demo/p95-16-1.pdf. Accessed October 22, 2019.

Dr. Jackson is board certified and received his DDS degree at the State University of New York at Buffalo School of Dental Medicine. He completed postgraduate training at St. Luke’s Memorial Hospital Center’s general practice residency program and the New York Maxicourse in oral implantology at the New York University School of Dentistry. Dr. Jackson is a Diplomate of the American Board of Oral Implantology/Implant Dentistry, a Fellow of the American Academy of Implant Dentistry, and a member of the ADA. He is the director of the Boston Maxicourse In Oral Implantology and a scientific reviewer for the Journal of Oral Implantology. Dr. Jackson has presented oral implantology lectures internationally and has published peer-reviewed articles in various journals on the topic of implant dentistry. He can be reached at bjjddsimplant@icloud.com or via the website bostonmaxicourse.com.

Disclosure: Dr. Jackson receives honoraria from Zest Dental Solutions and Implant Direct.

Related Articles

Effective Denture Stabilization in an Atrophic Mandible

Simplifying Implant Overdentures: Contemporary Overdenture Abutment and Attachment Systems

The Two-Implant Mandibular Overdenture