Imagine this scene: You are previewing tomorrow’s office treatment day and an endodontic patient is scheduled for 10:00 am. The tooth is the maxillary right first premolar. From your review of the number of probable canals, you know there is an 85% chance of 2 canals.¹ Which canal should you treat first? Does it matter? How do you coordinate the cleaning, shaping, conefit, and obturation sequence between the 2 canals if there are only 2 canals? After all, 6% of maxillary first premolars do have 3 canals. What cleaning, shaping, and packing mechanics are used where and when?
As with any goal, the first step is to have a plan that will produce the outcome we want. While different clinicians may choose different plans, the one chosen should be the one that is the most efficient and effective. This article is designed to make you think about your own current plan and to evaluate if it is the proper one for the patient at 10:00 am on your schedule.
I always teach “cleaning and shaping” as simple in concept, although deft skill is required in execution. I break the cleaning and shaping into what I call the “3 Fs:” namely: “Find, Follow, and Finish.”²

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CASE REPORT: TECHNIQUE

First F: “Finding” the Canals
Step No. 1: Take 3 different horizontal accurate periapical radiographs to learn as much as possible about the root canal system anatomy (Figure 1). In addition, I always take a bite-wing in order to evaluate the chamber anatomy. After anesthesia, place a rubber dam so tooth No. 5 is centered in the rubber dam and the rubber dam is flossed mesial and distal to prevent saliva leakage into the access cavity and endodontic irrigant leakage into the oral cavity.
Step No. 2: If the tooth does not already have cuspal coverage, reduce occlusion similar to cuspal reduction for the eventually required cuspal protection. This step prevents fracture prior to accomplishing restorative treatment, prevents unnecessary pressure to the attachment apparatus during chewing after the endodontic visit, and gives the dentist right angle occlusal surface canal length control reference.
Step No. 3: Prepare the access cavity using an organized access kit (Figure 2). Use concept of “penetrate and flare” with No. 2 round bur and peel off chamber roof.³ Smooth walls with tapered diamond, ensuring straight line access to canal orifi while taking care not to remove any dentin wall structure than is absolutely needed to preserve dentin for a ferrule. Care should be taken not to gouge the walls. Orifi should be visible and dentinal triangles should be removed with Gates Glidden drills or a single combination Gates Glidden drills (such as the X-Gates found in the Access Kit [DENTSPLY]) (Figure 3).
Step No. 4: Irrigate with full-strength sodium hypochlorite and agitate with the EndoActivator (DENTSPLY Tulsa) (Figure 4) in order to thoroughly clean the endodontic access chamber. Do not be in a hurry to “get your length of tooth,” as most dental students were taught during dental school. This is a time to slow down, explore, and experience any “booby traps” such as dense root canal system collagen, calcifications, necrotic debris, purulence, tortuous turns, or simply any anatomic information that you need to know. Eighty-five percent of the time, you will encounter 2 canals for tooth No. 5, as was the case with Nathan, our Read and Watch video series patient.

Second F: “Following” the Canals

Figure 1. Pretreatment Image of tooth No. 5. In order to accurately assess chamber and root canal system anatomy, always take a bite-wing and perpendicular, mesial, and distal periapical images.	Figure 2. Access Kit (DENTSPLY Tulsa Dental) is made of the essential endodontic burs.
Figure 3. “X” gates. This Gates Glidden bur efficiently combines Gates Glidden sizes Nos. 1 to 4.	Figure 4. Endo Acitvator (DENTSPLY Tulsa Dental). This simple device enhances cleaning of the root canal system and increases the number of portals of exit cleaned and sealed.
Figure 5. This apex locater (Root ZX [J Morita]) can be directly applied to rotary files to determine the physiologic constriction.	Figure 6. The full line of the ProTaper Rotary Universal files (DENTSPLY Tulsa Dental), from left to right, they are SX, S1, S2, F1, F2, F3, F4, F5. Usually only 2 shapers and 2 finishers are needed to create proper funnel shape preparations.

Step No. 5: Choose the easiest and straightest canal to clean and shape first. Typically, the palatal canal in the maxillary first premolar is the easiest and straightest. Precurve a No. 10 file with cotton pliers and set the rubber stop to the anticipated length. Gently, and yet intentionally, follow the No. 10 file to the anticipated reference, test with the Root ZX apex locator (J. Morita USA) (Figure 5) and verify with a radiograph. The goal is to “slip and slide” to the radiographic terminus (RT) (Figure 6). If the No. 10 file does not easily follow to the RT, recurve the file and follow again, since the curvature of the file and canal may not match. If the file does not follow deeper again, then restrictive dentin may be the cause. You have 2 choices: use a file with a narrower shaft such as a No. 8, or remove the restrictive dentin coronal to the No. 10 file depth with a rotary file such as the ProTaper S1 Shaper file and perhaps ProTaper S2 in the ProTaper technology (Figure 7). The ProTaper Shaping files (DENTSPLY Tulsa), because of their progressive taper, are extremely efficient and effective for removing restrictive dentin. This strategy is sometimes referred to in the endodontic literature as “early coronal enlargement.”
Step No. 6: Having followed the No. 10 file to the RT, which is validated by an accurate radiographic image and/or the apex locator, carefully reproduce the path by making small amplitude out and in vertical strokes of one mm. Continue until the No. 10 file can easily slip and slide in and out at greater and greater amplitudes up to greater than one-half of the canal length. This technique begins the “glide path” preparation. The glide path is defined as a smooth tunnel from orifice to the RT which is anatomically beyond the physiologic terminus (PT). This tunnel may be short, long, straight, curved, narrow, or wide. The key is that the walls are smooth in order to safely accept rotary shaping. A novice at glide path preparation may want to consider following the No. 10 file with a No. 15 file, which will create a slightly larger and safer glide path. Remember, however, that the No. 15 tip diameter is 50% wider than a No. 10 file. This jump in size increases the possibility of inadvertently producing a shelf that is undesirable with rotary since the rotary metallurgy does not easily flow over shelves. When using a No. 15 in a smooth No. 10 glide path, the safest and most efficient manual motion is the balanced force.

Third F: “Finishing” the Canals

Figure 7. Palatal first instrument to the radiographic terminus. It is important to have this radiographic evidence before continuing with cleaning and shaping.	Figure 8. Stropko Endodontic Irrigator (Obtura/Spartan, Vista). This novel and essential endodontic delivery system easliy fits onto triplex syringe. Water or air can be safely and efficiently directed.
Figure 9. Negative image of first instrument and conefit. By sequencing properly, 2 pieces of information can be ascertained in the same image.	Figure 10. Calamus Dual (DENTSPLY Tulsa Dental). This newly introduced device enables the dentist to both pack and backpack with the same unit.
Figure 11. Palatal and buccal conefit. The conefit film for all canals improves proper cone cutback.	Figure 12. Downpack. This image is useful in measuring if more or deeper packing is required after the downpack.
Figure 13. Backpack. Before access is repaired, the dentist should evaluate solid obturation.	Figure 14. Perpendicular Pack film.

Figure 15. Oblique Pack film. Multiple finish views allow dentist to “discover the anatomy.”

Step No. 7: Once the glide path is finished for the palatal canal, then rotary files can connect the dots between the minimum apical diameter and the orifice, which should be no wider than one-third of the root, in order to preserve maximum ferrule. When rotary shaping is complete (ProTaper technology is demonstrated in the Read and Watch video on cleaning and shaping sequencing and strategy found at dentistrytoday.com), irrigate thoroughly with the Endodontic Irrigator (Stropko) (Figure 8), which efficiently and effectively flushes away debris with sterile water. Then the palatal conefit is made. (Again, you can review the Read and Watch video for details.) Follow the buccal canal with a No. 10 file again to the RT. Place the palatal gutta-percha cone and take a radiograph with the palatal cone and No. 10 file in the buccal (Figure 9). If perfect, remove the palatal cone and place it safely onto a 2×2 gauze. Clean and shape the buccal canal, fit the cone, and then save it on a 2×2 gauze separate from the palatal cone. Then, check the fit of both palatal and buccal gutta-percha cones. Cut off the coronal surplus gutta-percha for reference reproduction and also make a plateau for cotton pliers to follow the gutta-percha cone to place with sealer when packing. Fit gutta-percha cone one-half to one millimeter short of the RT using the apex locator for additional guidance. In straighter, shorter, and wider canals, fit the gutta-percha cone farther from the RT or physiologic terminus if the apex locator identifies the foraminal constriction is shorter than you thought.
In more curved, longer, and narrower canals, fit the gutta-percha cone closer to the RT since apical movement and molding in this type of canal is less than in straighter, shorter, and wider canals. Regarding irrigation, use full-strength sodium hypochlorite while making the glide path. The sodium hypochlorite removes detached pulpal tissue, necrotic debris, biofilm, and kills bacteria. Change to 17% EDTA while shaping with rotary in order to remove the smear layer and facilitate carving dentin due to chelator. Be sure to use the EndoActivator as directed (refer to the Read and Watch video) in order to achieve 3-dimensional (3-D) cleaning.4
In maxillary molars, it is important to locate all orifi before proceeding with cleaning and shaping any particular canal. Some clinicians believe in the “divide and conquer” strategy of treating the easiest canal to the most difficult. The downside of this approach is, first, a narrow canal cannot actually benefit from the chamber irrigation until some of the restrictive dentin is removed, and second, leaving the more challenging canal to the end is typically a time when most dentists (and patients and dental assistants) are often running lower on energy. A strategic approach is to follow these canals (typically the mesionpalatal for maxillary molars) early on so that the cleaning and shaping irrigants truly facilitate cleaning these narrower and more tortuous canals.
Some master endodontic clinicians actually intentionally treat the most difficult canals first. Personally, I usually begin the glide path for all canals before cleaning and shaping any canal in particular. I achieve knowledge about the anatomy, gain confidence because I have evidence that I can follow all the canals, and I immediately adjust my approach to achieve the early glide path when restrictive dentin, for example, is present. I begin to plan my sequence and strategy so the endodontic mechanics are efficient, effective, and intentional.
Step No. 8: Flood the root canal system using maximum-proof alcohol and agitate with EndoActivator. Place paper points, then air dry with Stropko Irrigator. Prefit Calamus pluggers as demonstrated in Read and Watch video. Thinly coat palatal cone with canal sealer (Kerr Pulp Canal Sealer [Kerr]) and follow the cone to place. Remove surplus at orifice (Calamus Dual Obturation System in the Read and Watch video for details of SingleWave and MultiWave vertical compacton of warm gutta-percha technique) (Figure 10). After palatal canal surplus is removed, follow buccal gutta-percha cone to place in case there is cross-bridging between the palatal and buccal systems, in which case packing the palatal before buccal cone placement could result in gutta-percha and sealer flowing into the buccal network and prevent placement of the buccal cone (Figure 11). Using “Dual” cutaway buccal gutta-percha above the buccal orifice, pack palatal then buccal and take “downpack” film (Figure 12). Back pack using Calamus Dual (DENTSPLY Tulsa), create coronal seal to prevent future possible coronal microleakage, and take final finishing Pack films (Figures 13 to 15). If carrier-based obturation is desired, use canal size verifiers or use the last ProTaper rotary file that cut apical funnel taper shape as the verifier. Set the ProTaper Carrier one mm (plus or minus, depending on canal size and length as noted above), heat obturator and follow to place for 3-D seal.

References

1. West J. Endodontic predictability—“Restore or remove: how do I choose?” In: Cohen M, ed. Interdisciplinary Treatment Planning: Principles, Design, Implementation. Hanover Park, Ill: Quintessence Publishing; 2008:123-164.
2. West J. Endodontic update 2006. J Esthet Restor Dent. 2006;18:280-300.
3. Levin HJ. Access cavities. Dent Clin North Am. 1967;Nov:701-710.
4. Ruddle C. Hydrodynamic disinfection: tsunami endodontics. Dent Today. 2007;26:110-117.

Dr. West is the founder and director of the Center for Endodontics and continues to be recognized as one of the premier educators in clinical and interdisciplinary endodontics. He is president of the American Academy of Microscope Enhanced Dentistry (AMED) and past president of the American Academy of Aesthetic Dentistry (AAED). He received his DDS from the University of Washington in 1971, where he is affiliate associate professor. He then received his MSD in endodontics at Boston University Henry M. Goldman School of Dental Medicine in 1975 where he is a clinical instructor. Dr. West has presented more than 400 days of continuing education internationally while maintaining a private practice in Tacoma, Wash. He coauthored Obturation of the Radicular Space with Dr. John Ingle in 1994 and 2002 editions of Endodontics and was senior author of Cleaning and Shaping the Root Canal System in Cohen and Burns’ 1994 and 1998 Pathways of the Pulp. Dr. West is a thought leader for Kodak Digital Dental Systems and serves on the editorial advisory boards of: the Journal of Advanced Esthetics and Interdisciplinary Dentistry, the Journal of Esthetic and Restorative Dentistry, Practical Procedures and Aesthetic Dentistry, and the Journal of Microscope Enhanced Dentistry. He can be reached at (800) 900-7668 or via e-mail at johnwest@centerforendodontics.com.

Disclosure: Dr. West is a co-developer of ProTaper and Calamus endodontic technology, DENTSPLY Tulsa Dental.

Together, the authors explore the Endodontic-Endo-Restorative-Prosthodontic (EERP) continuum. This 2-part article will focus on the pervasive endodontic problems vexing patients, restorative dentist, and endodontists. The authors provide alternative models and thought processes to treat the tooth in a nontraditional approach—from cusp tip to apex. In addition, they will propose immediate tools to implement these important changes.

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INTRODUCTION
During patient treatment, the clinician needs to consider a multitude of factors that will affect the ultimate outcome. In simple terms, these factors can be grouped into 3 categories: operator needs, restoration needs, and tooth needs. The operator needs being conditions the clinician needs to treat the tooth. The restoration needs being the prep dimensions and tooth conditions for op­timal strength and longevity. The tooth needs being the biologic and structural limitations for a treated tooth to remain predictably functional. In this article, we want to discuss failures of endodontically treated teeth that occur not because of chronic or acute apical lesions, but because of structural compromises to the teeth that ultimately render the tooth useless. We want to coronally shift the focus to the cervical area of the tooth and create awareness for an endo-restorative interface. To this end, we will introduce a set of criteria that will guide the clinician in treatment decisions to maintain optimal functionality of the tooth, as well as help in deciding when the treatment prognosis is poor, and when alternatives should be considered.

ENDODONTIC ACCESS
Endodontic accesses are traditionally conservative to the occlusal/incisal tooth structure. However, with the changes that have occurred in restorative dentistry, this technique is unnecessarily restrictive for the operator. In addition, it can be damaging to the more critical cervical area of the tooth.
To introduce the problem, we will present a case (Case 1 shown in Figures 1 to 4) that we feel is quite representative of a large percentage of endodontic accesses performed by general dentists and endodontists. This tragic story is replayed thousands of times each day in the United States and Canada.

CASE 1

Figure 1. Case 1 (Figures 1 to 4): Preoperative view of tooth No. 19 in a 20-year-old female.	Figure 2a. Depicts the de-roofing problem discussed later in the article. The likely bur used by the referring general dentist was a 56-carbide. Red arrow delineates the typical gouging.

Figure 3. Eighteen-month follow-up. In spite of generous access and aggressive canal enlargement, the lesion on the mesial root continues to enlarge.	Figure 4. A more appropriate access shape is overlayed. Partial deroofing and maintenance of a robust amount of PCD is demonstrated. A soffit is depicted which includes pulp horns on mesial and distal.

In Figure 1, we see a lower first molar of a 20-year-old female. These “young” teeth are dangerously hollow to begin with. By the time that 2 dentists with good intentions had finished working on the tooth, the molar was nearly worthless. The most important structures were so badly compromised that the tooth was permanently crippled.

The general dentist created the first access using square ended fissure burs, (possibly one of the most iatrogenic instruments in the history of modern medicine and still the most popular bur in total sales¹) and with the type of dentin removal that is the standard today (Figure 2a). The tooth was then reaccessed by an internationally recognized endodontist (Figures 2b and 2c). This model for generous removal of pericervical dentin (PCD) is common in many specialty practices.
Eighteen months later, the lesion on the mesial root continues to enlarge (Figure 3). In Dr. Clark’s restorative practice and Dr. Khademi’s endodontic practice, such a tooth does not warrant endo­dontic retreatment. The wholesale loss of PCD has reduced the value of this tooth to the point that when the tooth becomes symptomatic, extraction and replacement with an implant is a better option.
In fairness to our patients, we must either change the process, or make implants a first option instead of the eventual option. The new model of endodontic access is superimposed over the tooth in Figure 4.

A NEW MODEL FOR ENDODONTIC ACCESS
As we deconstruct endodontic access, it is crucial to understand the 5 catalyst forces that will change the future of endodontic access and coronal shaping. They are the following: (1) implant success rates (the bar is raised); (2) operating microscopes and microendodontics; (3) biomimetic dentistry; (4) minimally invasive (MI) dentistry; and (5) aesthetic demands of patients.
In both of our practices, our endodontic goals and armamentarium have been in a constant state of flux for nearly a decade as we have collaborated to bring the EERP continuum to maturity. The goal? To satisfy the demands of the above mentioned “Big 5” forces for change. In so doing we have come to realize that, when preparing endodontic accesses, our previous needs as dentists were often in conflict with the needs of the tooth.

Table 1 represents the hierarchy of needs to maintain optimal strength and fracture resistance, along with several other characteristics needed for long-term full function of the endodontically treated tooth.
The brevity of this article precludes a full definition for all of the terms of the glossary (Table 2). However, there are 2 terms explained below. Others will be mentioned in the context of the feature cases.

Three-Dimensional Ferrule
The 3-dimensional (3-D) ferrule is the backbone of prosthetic dentistry. It has historically been described as axial wall dentin covered by the axial wall of the crown (or bridge abutment restoration). The research varies on the actual minimal vertical amount required, but the range of absolute minimums is from 1.5 to 2.5 mm.^2-17 The clinician must remember that build-up material, although necessary, does not “count” toward the ferrule. A more comprehensive view of ferrule is needed, and is embodied in the term 3-D ferrule. There are 3 components of the new ferrule, first is the vertical component, which is de­scribed above. The second component is dentin girth (thickness). The absolute minimum thickness is 1.0 mm; however 2.0 mm is obviously a safer number. The third component is total occlusal convergence (TOC), or net taper. That is the total draw of the 2 opposing axial walls of the prepared tooth to receive a fixed crown. A net taper or TOC of 10° requires 3.0 mm of vertical ferrule; a TOC of 20° requires 4.0 mm of vertical ferrule.^18-32 Deep chamfer marginal zones common with today’s porcelain crowns typically have a net taper of 50° or more, and therefore many of today’s aesthetic margins lose a millimeter or more of there original potential 3-D ferrule at the crown margin interface.

PERI-CERVICAL DENTIN
PCD is the dentin near the alveolar crest. While the apex of the root can be amputated, and the coronal third of the clinical crown removed and replaced prosthetically, the dentin near the alveolar crest is irreplaceable. This critical zone, roughly 4 mm above the crestal bone and extending 4 mm apical to crestal bone, is sacred for 3 reasons: (1) ferrule, (2) fracturing, and (3) dentin tubule orifice proximity from inside to out. The research is unequivocal; long-term retention of the tooth and resistance to fracturing are directly related to the amount of residual tooth struc­ture.^2,33 The more dentin we keep, the longer we keep the tooth.

SACRIFICE VERSUS COMPROMISE

Figure 5. Radiographically ugly but clinically successful (20-year) endodontic treatment. This case was very likely done on a vital tooth. Residual PCD has buttressed this tooth to avoid fracture.

In Case 1, significant dentin was sacrificed to facilitate expedient and safe instrumentation, and yet the endo­dontic treatment was failing. Contrast that case with the tooth seen in Figure 5. There was a significant compromise 20 years ago, when the dentist stopped removing dentin because the complete canal system could not be located and less than half of the distal root was filled. Despite this shortcoming, the “poor endodontic result” was successful, and the well-preserved PCD has buttressed the tooth making the overall case a smashing 20-year success.

LOOK, GROOM, AND FOLLOW: SHAPING VERSES MACHINING
A Mini-Interview/Dialogue With the Authors

Why are Gates Glidden burs so problematic?

Figure 6. Extensive coronal flaring results in extrusion of obturation material in the furcation. The furcal strip perforation is a perfect example of the dangers of “Blind Funneling” with Gates Glidden burs.

Dr. Clark: I abandoned Gates Glidden (GG) burs 12 years ago. I will explain why. Since the introduction of rotary files, GG burs have been used more aggressively and with more reliance on larger sizes (4, 5, and 6) to reduce binding and fracture of rotary files. GG burs have always been considered “safe” because they do not end cut and are self-centering. There is a significant problem here, which is “cervical self-centering.” Because the shank of the GG is so thin, it is difficult to “steer” the GG bur away from high-risk anatomy. As the GG bur straightens the coronal, or “high-curve,” it can shortcut across a fluting or furcation, and weaken and/or create strip perforations (Figure 6).

Why are round burs so destructive?

Figure 7. Text after text shows the same round bur technique relying on tactile feedback as the round bur drops into the chamber.	Figure 8. If the pulp chamber is sufficiently large enough, then a round bur can truly “drop in” to the pulp chamber as shown here with a No. 6 round bur superimposed on the lower molar of this 11-year-old child.

Figure 9. This case is much more representative of the spectrum of cases typically presenting for endodontic treatment.

Dr. Khademi: The traditional way of initiating endodontic access is predicated on mental models that do not represent the day-to-day clinical reality presented to the clinician. Text after text shows the same round bur technique relying on tactile feedback as the round bur drops into the pulp chamber (Figure 7). These kinds of images, so frequently shown in dental school, textbooks and lectures are predicated on mental models based on occlusal decay in children.
If the pulp chamber is sufficiently large enough, then a round bur can truly “drop in” to the pulp chamber as shown here with a No. 6 round bur superimposed on the lower molar of this 11-year-old child (Figure 8).
The reality of day-to-day clinical practice is quite far removed from this, and these deeply ingrained mental models are a setup for occult iatrogenic trauma. More realistically, the case shown in Figure 9 is much more representative of the spectrum of cases typically presenting for endo­dontic treatment. Clearly, trying to drop a round bur into the scant or nonexistent cham­ber is not going to lead to the desired outcome even for a skilled clinician.
Instead, the size of the burs relative to the chambers, the omnidirectional cutting blades (which side cut very ag­gressively), and chatter common with this bur design are much more likely to lead to the kinds of outcomes seen in Case 1 (refer again to Figures 2a to 3).

Figure 10. (Mural is described in the text.) Note: Blue arrows indicate gouges. Red arrows indicate perforations. “JK” indicates that case was done by Dr. John Khademi with adherence to the modern model of directed dentin conservation.

So while round burs are destructive because they contribute to, or exacerbate, these problems; it is really the tactile based mental models predicated on these kinds of drawings showing round burs dropping into the pulp are the ultimate problem. Care and magnification can compensate, but only to a degree (Figure 10).

Figure 10: First Row
Note: Blue arrows indicate gouges. Red arrows indicate perforations. “JK” indicates that case was done by Dr. John Khademi with adherence to the modern model of directed dentin conservation.
Upper Bicuspids are deceptively difficult. At the peri-cervical level, they can be half as wide mesiodistally as buccolingually. This is further complicated by frequent invaginations midroot where round bur access is typically placed. This sequence shows the typical occult gouging in the first case and the misangulation and gouging as the sequence progresses ending in a perforation of a bridge abutment. The correct mesiodistal access of this tooth should be no wider than the coronal canal shape. The access may slightly converge from a broad buccolingually pulp chamber as it moves towards the occlusal in the buccolingually dimension. Round burs simply cannot create this kind of shape.

Second and Third Rows: Molars
I was overwhelmed with the sheer number of gouged up molar cases while mining my The Digital Office image database. Essentially all previously accessed molars were gouged to some degree. The first upper and lower molar cases show what many might consider acceptable access extension and were obviously cut with round burs. Both are gouged. The third upper and lower cases both have frighteningly thin pulpal floors with blushing dentin. The upper fourth case is deceptive in that it is perforated, while the worse looking lower case is not, but the pulpal floor is paper-thin. The last upper molar case (which has a Class V resorption repair) shows what is possible with practice, microscope level magnification, an assistant’s side and the right instruments. The lower molar shows the type of access that should be routinely achievable with high-powered loupes and the right instruments.

Why is complete de-roofing so dangerous?

Dr. Clark: When Dr. Khademi first mentioned maintaining a “soffit,” which is a little bit of roof around the entire coronal portion of the pulp chamber, I was perplexed at first. Today, it makes perfect sense because cleanup is easier, and I feel a great sense of pride in this important advance in MI access. Research will certainly need to be done to validate the strength attributes of the roof strut, or soffit. However, in the absence of a compelling reason to remove dentin, our default position should always be the conservative one. This 360° soffit, or roof-wall interface, can also be compared to the metal ring that stabilizes a wooden barrel.

Dr. Khademi: Presuming one could drop into the pulp chamber in the way drawn and described above, the chamber roof would now be removed by scooping it up and away with a round carbide. A 2-dimensional (2-D) drawing, with the relatively small size of the bur and chamber roof overhanging a large pulp chamber, makes this seem like a reasonable proposition. The chamber walls are somehow always drawn flat even though they are cut by a round bur.
In reality, it is truly impossible to do: to cut flat walls in 3-D with a round instrument. What happens is that the chamber is unroofed in some areas leaving pulpal and necrotic debris, and the walls are overextended and gouged in other areas. Furthermore, the internal radius of curvature at many of the pulpal line angles is simply too small for all but the smallest of round burs.

Figure 11. Illustration comparing the CK endo access bur to the corresponding round bur.

In the final analysis, round burs point cut in an endodontic access application, when instead what is needed is planing. What is needed is a new set of mental models based on vision, and a new set of instruments reflective of the task at hand and the desired shaping outcomes. The new vision based mental model is look, groom, follow. The new burs are all rounded-ended tapers (Figure 11). It is an illustration comparing the CK Endodontic Access bur to the corresponding round bur. The tip size of these burs is less than half as wide as the corresponding round bur. One of the prototype CK Endodontic Access burs has had (right) is shown and contrasted with the corresponding surgical length round bur (left). These burs, designed by Drs. Clark and Khademi, will be available from SS White Burs.)

CASE 2
This case (Figure 12) shows a completely different vision-based model (look, groom, follow) for creating access to the root canal system. This model is predicated on a reversal of many traditional access concepts, which required the elimination of some instruments considered integral to endodontic access and the consequent development of new instruments and techniques.

Figure 12. Mural is described in the text.

First, restorative materials are sacrificed so that PCD is not compromised. A wide swath is cut through the occlusal surface of the restoration just to the level that dentin is encountered. This generous access allows the clinician to more accurately read the color map looking for clues leading to the initial locations of the pulp tissue remnants (PTR), or where the PTR were in a necrotic system (PTR space).
Second, the clinician superimposes a mental framework of the expected canal system onto the portions of the color map that are visible. The color map is not a steadfast light/dark or a definitive color. In addition, it is often variable in different parts of the system due to leakage, restorative materials, and different modes of calcification. The color map must be interpreted through this framework.
Third, once a definitive PTR, or PTR space, is located; it is followed visually and slowly traced out using ultrasonics, or CK burs. Given the size of these burs, explorers become even more pointless. (An examination of the tips of used explorers typically found in a dental office will confirm this.) Poking at the pulp with a blunt explorer does not serve any good purpose. Pictured are: a Ball Ultrasonic (one of the CK burs), a Pear Ultrasonic, a CPR-7, and a BUC 1A. The second picture shows the tip of one of the CK burs with the smallest Munce Discovery Bur. (Dr. Khademi’s skin/thumbprint can be seen in the background.)
Fourth, expecting even the smallest round bur to “drop in” on this unexciting, routine, lightly calcific case is a setup for the kinds of problems that have been discussed earlier. The clinician uses these small CK burs in a low-speed latch (or high-speed) to trough around the periphery of the old pulp chamber looking-grooming-following and connecting the visible PTR with his mental model as a guide filling in the missing pieces. A pulp stone is troughed out following these PTR, and broken free with a spoon excavator.
Fifth, the pulpal floor is cleaned up slowly and carefully with special attention to complete troughing out of the periphery of where the pulpal floor meets the chamber walls. The points of negotiation (PON—formerly canals) to the canal system almost invariably exit the chamber at points along this periphery. Note that an additional PON at t

In an interview conducted by Dr. Damon Adams, Dentistry Today’s editor-in-chief, Dr. David Hornbrook shares his opinions, knowledge, and vast clinical experience on what he feels are some of the hottest topics in dentistry today.
Dr. Hornbrook lectures internationally on all facets of aesthetic dentistry. He founded and was the past director of PAC~live and the Hornbrook Group. He is the past clinical editor of the Dental Practice Report, a member of the Esthetic Dentistry Research Group, which publishes REALITY and REALITY NOW, and is on the editorial boards of many of the leading dental journals. He is also the past editor of the Journal of the American Academy of Cosmetic Dentistry.

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Dr. Adams: I’ve heard you say numerous times that this is the most exciting time in dentistry, because of all the changes that are occurring. In your opinion, what are the most exciting changes that we are currently witnessing?

Dr. Hornbrook: As I travel around the country and interact with other clinicians, laboratories, and manufacturers, I have found the 3 hottest topics today are metal-free indirect dentistry, prepless and minimal preparation veneers, and the use of lasers in dentistry. The technological changes taking place are truly revolutionizing the way we practice dentistry and the manner in which laboratories are fabricating restorations. Digital dentistry and the use of computer-aided design/computer-aided manufacturing (CAD/CAM) fabrication not only improves the quality and accuracy of the dentistry we do, it allows for faster turn around time and has overcome so many of the compromises we have seen with indirect dentistry in the past.
With the advancements in digital dentistry, we are seeing changes in how we take our impressions for indirect restorations. I personally think the traditional “squirt the material out of a gun and wait for it to set 5 minutes in a messy tray” is rapidly going to be a treatment modality of yesterday. I believe that few clinicians will be using “impression material” as we know it today, 5 years from now. Digital impressions are more accurate and comfortable for our patients. If you think about where our compromises in indirect dentistry arise from, they have their roots in the inaccuracy of polyvinyl impressions as well as in the pouring of the impressions in dental stone. If I can now scan the preparation instead of taking a traditional impression, and then either modem that scan to a milling machine I have in my office or directly to the laboratory, I have eliminated many of the potential errors. CEREC (Sirona) users have already been doing this for years with excellent results, but they were forced to endure a substantial initial cash outlay for the equipment. If doctors can now purchase a digital scanner, without the expense of an actual in-office milling machine, at a fifth of the cost, I think we are going to see much wider spread usage of this technology.
Laser technology has been used in dentistry of almost 2 decades, but it has not really been utilized as much as we have seen in the last few years, and probably what we can expect in the very near future. With lasers being produced with reduced cost and size, more reputable manufacturers getting involved, patient demand, and better and more controlled research; these are all reasons for the increase in laser popularity. I believe that the use of lasers in periodontal procedures will become a “standard of care.”

Dr. Adams: David, you mentioned prepless and minimal prep veneers. Why are these techniques such a hot topic at this time?
Dr. Hornbrook: I receive more questions about issues regarding prepless and minimal prep veneers than any other right now. The interest in these techniques is obviously consumer driven and the increased interest by clinicians is a direct re­sult of their patients asking about these conservative treatment possibilities. This interest is primarily due to the fact that a major dental manufacturer went directly to the consumer and said, “You’ve got to have these.” Now the consumer, having read or seen marketing propaganda, comes to our office asking about treatment.
The concepts of prepless and minimal prep veneers have been around for many years, but it has not been until recently that we have seen such widespread interest among clinicians. Many clinicians placing veneers today were previously taught that they must do relatively aggressive preparations to yield acceptable aesthetic results. As a result, the ability to place aesthetic veneers without preparation is still a relatively new concept for most clinicians, yet they should be familiar with it. This is a huge paradigm shift for so many clinicians, including for me. Previously, we have always had the mindset that “if you are going to add something on the facial of the tooth, then you must remove something to make the room.”
Like many clinicians, I had quite a few patients who either declined treatment because they would not let me prep their teeth, or who never approached me because they were concerned about getting their teeth prepped. As I begun looking more closely at this technique, prior to really understanding how to make this work, I struggled with the fact that the nonprepped veneer cases that I had seen all looked bulky, ugly, and too opaque. I did not think that they were representative of the type of artistic dentistry that I wanted to provide. I realize now that those cases were a direct reflection of a lack of preplanning and designing the smile, incorrect use of materials, the quality of the ceramists used, and not necessarily because they were minimal in their preparation.
As dentists practicing in this new millennium, we need to look very closely at the techniques of prepless and minimally prepared veneers. We need to decide if these are services that we should offer to our patients, and if it will provide a good aesthetic result and a successful long-term prognosis. It’s important for clinicians to realize that there’s not just one certain brand of ceramic, one particular manufacturer, or one specific laboratory that can do your prepless veneer restorations. The prepless or minimal prep veneer is a technique, not a specific product. Any ceramic can be used, and there are many expert ceramists who can give you wonderful results.
Success with these techniques is reliant on the communication process with the laboratory technician and in case selection and diagnosis. Many clinicians I have spoken to, when the treatment is a traditionally prepped veneer case, spend a lot of time in the smile design process and write a very detailed laboratory prescription. Yet, when they do a nonpreparation case, they spend very little time in the design process. We need to design the case exactly like we would design any other veneer case. The process of diagnosis becomes even more important with minimal preparation cases—if you want to obtain predictable results. With prepless veneer cases, I have to have more input from my ceramist to see if a result can be delivered that will make both me and my patient happy.
In my opinion, many clinicians look at the prepless veneer as a “lesser” ve­neer, or cheaper veneer, because it is not prepped. Because of this, they use inferior laboratories, or are not as concerned about researching the best materials available. That a huge mistake! Some that I have spoken too even take alginate master impressions, pour-up the models in their office, and send them to the laboratory. Then, when the case is returned with ill fitting margins or compromised aesthetics, they blame the prepless technique for the subpar restorations.
With prepless or minimal prep cases, we must have an intimate relationship with our ceramist. Success is dependent on educating our ceramists, and getting them involved in utilizing the materials to do prepless or minimal prep veneers. The dental laboratory technicians need to give us input as to whether or not they can deliver acceptable results. I’ve had patients say, “I do not want my teeth prepped” and my response was, “I don’t know how aesthetic this is going to look; I think it’s going to look bulky or fake, or it’s not going to be something that looks like the pictures in my reception room.” I’ve have had cases where I have taken impressions and sent them off to the ceramist, despite the fact that I didn’t think it was going to look good, just to get their input. The ceramist, after re­view­ing the case, calls me back and says, “You’re kidding right? I can’t do this! It’s going to be bulky and ugly, and because this one tooth is flared, the entire case is going to be too far facial.” This is the kind of important input I want from my dental technicians.

Although prepless veneers are not indicated for every case, or even the majority of the cases, it certainly should be a part of every clinician’s restorative armamentarium. It is a great option on young adults or teenagers with microdontia, or post­orthodontic treatment. Working with the orthodontist to align teeth correctly can yield excellent results (Figures 1 to 4). Many of these thin veneers are only 0.2 mm thick, so they can look natural and not overly bulky (Figures 5 and 6). Currently, I am using a leucite-reinforced pressed ceramic for my prepless veneers called Emprethins (emprethin.com), be­cause I like the physical properties of this ceramic. The bottom line is to be educated and truly understand the indications and contraindications of this technique before attempting a case or dismissing it as not a possibility.

Dr. Adams: Metal-free dentistry has become a goal for so many clinicians. Are we to a point where one can truly eliminate metal from their restorative practice?

Dr. Hornbrook: We are almost there. Certainly, in direct dentistry, we can eliminate metal. The new composite resins, especially the low shrinkage, high wear resistant resins have become an excellent alternative to amalgam. They can be more conservative and actually strengthen and support the tooth, whereas amalgam has been shown to compromise tooth integrity. Obviously, technique sensitivity when placing resin restorations is higher than amalgams, but if a clinician is willing to take the time to practice excellent dentistry, the final results will be superior, in my opinion. For single tooth indirect dentistry, we can absolutely eliminate metal.

When treatment-planning indirect dentistry, all-ceramic crowns have proven to be an excellent alternative for metal-based restorations. The ability to adhesively bond many of the ceramic materials yield improved integrity and sealing of the margins, better resistance and retention, and improved aesthetics. A major advantage of using the adhesively-bonded metal-free restorations is the ability to be more conservative since most require only 1.0 mm thickness as compared to 1.5 to 2.0 mm for metal supported restorations; maintain our margins supragingival; and place more intracoronal restorations rather than be forced to wrap over cusps that were traditionally done with metal-supported restorations (Figures 7 and 8). The disadvantage of some of the all-ceramic materials, (ie, leucite reinforced and powder-liquid ceramics) is the need to adhesively bond them to place, which requires more attention to technique than we had been used to with metal-reinforced restorations. With the new high-strength ceramic copings, such as aluminum oxide and zirconium oxide, we can now traditionally ce­ment metal-free restorations using the same cements that have always been used with metal. Although the zirconium oxide does introduce some opacity, and thus slightly compromises the aesthetic value of a restoration compared to bonded ceramics, we can achieve superior aesthetics compared to metal-supported restorations. These zirconium-supported ceramics can also be used for multiple-unit bridges, in both the anterior and posterior (Figures 9 to 12).
Nonmetal restorations can be used to replace metal-supported res­torations in all instances, except if the clinician desires to place a precision or semi-precision attachment onto a crown to support a removable partial denture. While partial rests can be placed in all-ceramic crowns, female or male attachments cannot be incorporated into these, and a metal-reinforced crown would need to be utilized.
In my practice, I have eliminated metal almost completely. The only place that I currently use metal is in the implant body itself, and the screw that retains the all-ceramic abutment.

Dr. Adams: Other than the aesthetic advantages, what are other reasons that clinicians might be interested in finding and utilizing metal-free options.

Figure 13. Preoperative photo showing short teeth, and the need for gingival recontouring to increase teeth length.	Figure 14. Immediate postoperative photo of maxillary right, after osseous recontouring. Gingival tissue was recontoured, and approximately 3.0 mm of bone was removed via laser recontouring.

Figure 15. Two month postoperative photo, following osseous recontouring and veneer placement.

Dr. Hornbrook: I already mentioned conservation of tooth structure, which I think is one of the major advantages. Another advantage is certainly metal toxicity, especially when using nonprecious metals in many of these restorations. We know that a majority of our patients have some negative reaction to nonprecious metals such as nickel and beryllium. In my opinion, as we see more of our indirect dentistry being fabricated by overseas laboratories, we may potentially see an increase in problems with the metals being used. We are also going to see galvanic reactions between the different metals used in the mouth, thus potentially compromising both tooth and gingival health. My stance on this is that if we have an option to use a metal-free restoration, we should do so.

Dr. Adams: You mentioned digital impressions earlier. Do you think the use of digital impressions is going to overtake the use of physical impressions, and what will be the hurdles for dentists in adopting this new technology?

Dr. Hornbrook: As I mentioned earlier, in the very near future, digital impressions will replace traditional impressions for most astute clinicians. It just makes sense in terms of accuracy and ease. It will be a less expensive option in the long run. The dental laboratory technicians are embracing this technology because of its accuracy, and the ability for the clinician to see the margins of the preparation immediately in the digital impression. With the increase in CAD/CAM restorations, the dental laboratory technicians will be able to fabricate these restorations more quickly, at a lesser expense.
The hurdles will be the same as it has been for so many new technologies in dentistry, and that is the fear of change along with the initial upfront investment. This technology is going to be a huge paradigm shift for clinicians, but as more systems become available and the technology becomes more user friendly, more dentists will adopt it as their standard protocol.

Dr. Adams: You mentioned lasers in dentistry as another hot topic, what laser or lasers are you currently using?

Dr. Hornbrook: I am currently using a diode and an erbium-doped yttrium aluminum garnet (Er: YAG) laser. The diode is for soft tissue only, whereas the Er: YAG can be used for both soft and hard tissue—the hard tissue being dentin, enamel, and bone.
Lasers are a hot topic everywhere in our society; whether its skin resurfacing, hair removal, tattoo removal, laser etching, or fabrication of intricate instrumentation and devices. Lasers have always been considered cutting edge and state-of-the-art. I’ve been working with soft-tissue lasers for close to 15 years, and they are something that I cannot imagine practicing without. I began using the diode laser, as an alternative to the electrosurgery unit and scalpel, to alter gingival contours in smile de­signs. The advantages were many, but most notably increased predic­tability and no postoperative discomfort following treatment.
Besides using the diodes for smile designs, we’re seeing unbelievable results with periodontal treatment when used as an adjunct to traditional professional cleaning with our hygienist. There is great research regarding bacteriostatic and bacteriocidal properties, as well as osseoclast and osseoblast stimulation. We are not only seeing improved gingival health, we are also seeing bone regrowth in deep pockets with bony defects. I personally think the use of the laser in periodontal treatment will become standard of care. I already think that, but as we discussed earlier, acceptance of new technologies and shifting paradigms is always a slow process in dentistry. The cost of diode lasers has gone from being over $40K per unit to under $10K. In addition, where they were once big and bulky units that needed to be on carts, they are now small and very portable. The decrease in both size and cost is going to make this technology more utilized.
Where the diode can only be used for soft tissue, the Erbium can be used in other capacities. Although it is excellent for soft-tissue recontouring during smile designs, we can also use it for tooth preparation, often times without anesthesia. The Er: YAG laser can be adjusted to be tissue or substrate specific, so we can also be much more conservative when replacing defective restorations, such as pre-existing resin or ceramic restorations. We can set the laser to a specific setting to remove only resin, and have very little effect on enamel, so we’re replacing those restorations without destroying additional tooth structure.
One use of the Erbium laser, that I am very excited about, is using it for a procedure called “closed flap osseous reduction” (Figures 13 to 15). This is basically crown lengthening without laying a flap to expose the bone. I can recontour the tissue to where I want it to be, irrelevant of potentially violating the biological width; and then place the tip of the Er: YAG laser into the sulcus and recontour the bone to re-establish healthy biological width. The healing is amazing and postoperative discomfort is nonexistent. Although many of the successes are anecdotal, there is great research on the response of bone to the Er: YAG laser and the quality of healing when compared to a diamond bur, or other types of lasers.

Dr. Adams: Let’s change the topic a bit at this point. What are your thoughts regarding dentists being able to administer BOTOX and injectable dermal fillers in their office?

So what’s the bottom line? I be­lieve that if we’re going to be designing smiles, we are the ones who should be designing the lips, not the dermatologist or the plastic surgeon. It would be nice if the ADA would get involved in helping support those dentists who want to get more involved with this and try to achieve some consistency with our various State Boards.

Dr. Adams: As new technology and materials are introduced, it seems that dentists are becoming more and more confused. What are your thoughts on this Dr. Hornbrook?

Dr. Hornbrook: You’re absolutely right! Clinicians become confused, because manufacturers tend to confuse us. The names they use for new products, the introduction of new products without training support, and the creation of too many products that are the almost the same but different, all play into this problem. Many new products are designed for specific techniques without proper educational opportunities. Many manufacturers have introduced restorative materials to the dental technicians first, while not educating the clinician, so the ceramists are sitting around waiting for dentists to prescribe a certain restoration and we don’t know anything about it. Manufacturers need to take a very active role in education, but dentists need to take responsibility for the lack of education as well. As dentists, we need to take an active role in really understanding what changes are occurring in our profession and how new technology and materials can improve the quality of care provided for our patients
As an educator, I see such a range of how many hours a clinician spends being educated and updated. I’ve met dentists that attend hundreds of hours a year, as well as those that attend just enough to get their license renewed. Since the changes in our profession are happening so fast, I think dentists need to step back and say, “I need to take an active role in educating myself as to what’s available, and to stay updated.” It’s our professional responsibility to stay educated for our patient’s benefit.

Dr. Adams: Thanks for taking the time to share your thoughts and expertise with our readers! Your contributions to our profession are admirable, and much appreciated. Is there anything else that you would like to add? In addition, what recommendations can you give to young dentists who want to raise the level of care in their practice?

Dr. Hornbrook: I think dentistry is an unbelievable profession, and it’s only going to get better! I have 2 sons, a 10- and a 14-year-old, and if they came to me and said, “Dad, we want to grow up and be a dentist,” I’d be fired up about that! I’d do everything I could to make sure that happened as quickly as possible. I think the profession is awesome now, and I can’t imagine where it’s going to be 20 years from now.
However, let’s address the challenges with the young dental school graduates. Dental school hasn’t changed a lot. The things being taught today at the dental school I went to is pretty much the same thing that I learned, and what the graduates were learning 10 years prior. So where are they going to learn the new techniques and technology, that will enable them to truly love and enjoy our profession like I do today?
My biggest advice is stay educated. When they graduate, I think a lot of these young professionals are ready to take a break from education. because that’s all they’ve been doing for the last 25 plus years. It’s too easy for many of them to be complacent, thinking they already know pretty much everything. These young clinicians need to take control and grab the reins of their careers. How? I would highly suggest that they find a mentor, or a group of mentors, who will motivate, excite, and challenge them. Why make the same mistakes that those before you made? Why wait to gain experience, before you learn how to do it right? Everyone can benefit from sharing their experience, especially from the mistakes that have already been made.
The best advice I can give to young clinicians of any age; stay educated, stay motivated and get fired up about our profession! I think our profession should be considered like a hobby that we just happen to have the opportunity to make a great living from doing! Stay excited about your future, and if you’re not excited, then find a way to ma

In an interview conducted by Dr. Damon Adams, Dentistry Today’s Editor-in-Chief, Dr. Michael Tischler maintains a private practice in Woodstock, NY.

Dr. Adams: As a general dentist, how have you incorporated dental implant surgery and prosthetics into your practice so successfully?

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Dr. Tischler: It starts with a strong belief that dental implants are the ideal way to replace missing teeth. If you look at the literature comparing the other options available to replace missing teeth; a fixed tooth borne prosthesis, a removable appliance, or a bonded fixed prosthesis; dental implants offer the best long-term success without being a detriment to adjacent teeth. At the same time, according to the literature, dental implants preserve or stimulate bone. This information was first brought to my attention years ago by Dr. Carl Misch, and I am so grateful for his mentorship and training throughout the years through his institute. Once you really understand that dental implants best recreate natural tooth function in edentulous regions for both partially and fully edentulous areas, you just want to convey this to your patients.
Overall, I believe that the success rate with dental implants I experience in my practice is related to the principles of treatment planning that translate to favorable loading forces on implants. When dental implants can be treatment planned so that their placement positions do not create undue occlusal forces and angulations, there is less bone loss, and prosthetic breakdown. My friend Dr. Scott Ganz has said that, “patients come to us for teeth not implants.” I like that quote because that is how I treatment plan, from the prosthetic end result backwards. Once you decide with the patient what the end result will be, you can then plan a case by looking at the bone levels and soft tissue architecture. This is the foundation for implant dentistry.
From a practice management standpoint, successful incorporation of implants into my practice has been facilitated through good marketing and staff support. My Web site tischlerdental.com has a lot of information about dental implants that many patients utilize. My team is totally on board with the clinical benefits of dental implants and they convey that message to our patients on a daily basis in person and on the phone.

Dr. Tischler in surgery placing dental implants. Note use of high magnification loops and surgical lighting. Hands-on courses are an important part of training for dental implant surgery and prosthetics. Dr. Tischler offers many hands-on courses throughout the United States and at his teaching facility in Woodstock, NY.

Dr. Adams: What is new and exciting in the field of implant dentistry?

Dr. Tischler: The utilization of cone beam computed tomography (CBCT) is, in my opinion, the most dramatic influence and exciting thing happening right now. The technology that CBCT offers, allows for a dramatic increase in safety, and predictability in implant treatment planning. In my office I have an iCAT CBCT machine, and for the past 2 years, I have not placed a dental implant without using it. There is no other way to get 4 views of a jaw including a 3-dimentional (3-D) view. I can outline the mandibular nerve, visualize bone density, sinus anatomy, and any potential pathologies, as well as many other parameters. Once I plan the location of implants to be placed, I can have a surgical guide created that accurately translates to the mouth, the correct location, angulations and depth for implant placement.
The most recent development in the CBCT field is the formation of third-party companies such as 360 Imaging in Atlanta that process and treatment-plan the information from a CBCT and allow for an online meeting between the surgical and restorative doctors. This is first time, in my view, that the team approach between all doctors involved with a patient’s treatment can easily be coordinated and communicated in an effective manner. This now allows the restorative doctor to help guide the surgeon based on a prosthetic end result. This now allows dialogue between treatment doctors and a realistic and powerful team approach.
In general, I believe the predictability that CBCT offers will allow the number of dental implants placed to increase and to help the many patients out there that need it.

Dr. Adams: Should general dentists place dental implants?

Dr. Tischler: Implant dentistry is not an ADA-recognized specialty. In this country, a licensed dentist can surgically place dental implants as long as they abide by the standard of care for dental implant placement. Dental implant surgery is not generally taught in dental school so a graduating dentist must learn this standard of care through postgraduate educational venues.
The path I took for this was a conglomerate of what I feel are some of the best educational venues in this country by practitioners that are willing to share their knowledge about implant surgery and prosthetics. The Misch Institute is based on the teachings of Dr. Carl Misch, the author of the best selling textbook in the world on implant dentistry. The fundamental principles taught there, and the availability to bring your own patients, is a great opportunity to learn. The instructors at the institute are there to guide you during your first few surgeries, increasing your confidence as you start out. This was powerful for me. Supplementing that with other surgical courses that are available, such as Dr. Mike Pikos’s MAP Institute in Florida, Dr. Pat Allen’s soft tissue course in Dallas, and Drs. Salama and Garber’s courses in Atlanta, were also part of my educational journey. There are also many university-based programs that offer surgical guidance. A dentist can attend as many courses as they want but at some point they are going to have to get in the mouth and start actually placing implants so they can build their comfort level and skill levels.
I also feel it is important to join some of the major implant organizations and get involved. The Inter­national Congress of Oral Implantologists, the American Academy of Implant Dentistry, the Academy of Osteointegration offer great educational venues, annual meetings and periodicals to stay abreast in the field of implant dentistry. While the credentials these organizations offer, give a practitioner something to hang on their wall, the real value in the credentials are the process that it takes to get them. The American Board of Oral Implantology Implant Dentistry of­fers a board-certification proc­ess that I have completed. This process, offers a similar testing protocol that board certification requires for other dental specialties. Just the vigor’s of this exam and preparing for it, I feel brings a doctor to a higher level of care. One other thing I recommend is for general dentists to join the American Academy of Periodontology (AAP) as an associate member. A sponsorship is needed by a periodontist who is an AAP member to join. The AAP’s Journal of Periodontology and the annual meetings offer excellent information on implants and grafting.

Dr. Michael Tischler performing implant surgery at his office in Woodstock, NY. (Note sterile surgical protocol.) Three-dimensional view from cone beam computed tomography (CBCT) showing implant planning of a deficient mandibular arch prior to implant placement for mandibular overdenture. Laboratory model of abutments and soft tissue model for full arch implant supported fixed prosthesis. Dr. Tischler teaches that restoration of a full-arch dental implant case is easier than tooth-borne crown and bridge. Clinical view of BioHorizons stock abutments to support a fixed prosthesis.

Dr. Adams: You have stated in your lectures and articles that fixed implant dentistry is easier than crown and bridge on natural teeth. Can you explain this?

Dr. Tischler: The steps involved in taking an impression, and having the laboratory perform the needed steps to deliver a final fixed prosthesis, is less labor intensive and equally predictable as a tooth-borne crown and bridge impression. I often say that to perform fixed implant prosthetics, a dentist has to be good at screwing and unscrewing parts, and taking impressions. Any dentist can do that! The dental laboratory technicians really do a majority of the work in the lab. They prepare or create an abutment, create provisionals, and can order all parts and pieces needed. The dental lab is actually an integral partner in the implant team.
The fact is that since most dentists don’t understand the parts and pieces involved it becomes intimidating. When you don’t understand something you tend to shy away from it. It is a shame because the literature supports the fact that a single tooth implant has better longevity than a 3-unit bridge, and it is easier to clean for the patient, puts less stress on adjacent teeth, and stimulates the bone.
I do believe for the entire process to be predictable and simplified for the restorative dentist, the surgeon must create the correct hard and soft tissue support for this to happen. Unless an implant is relatively parallel, in the correct position form an occlusion and aesthetic standpoint and the soft tissue is healthy, the process to restore an implant is made more difficult. This is why the restorative dentist must get involved in the process to make sure that in the end, the prosthesis is correctly supported by the implant. It all comes down to correct treatment planning. Also, the importance of bone grafting for success of the final prosthesis cannot be overemphasized. Correct bone levels will dictate the implant to crown ratio, papillae support, and angulations of implants. These are real issues that define the long-term success of a case. This is why I emphasize bone-grafting principles in my courses.

Dr. Adams: With so many implant companies and products available, how do you choose what to use?

Dr. Tischler: It is amazing how many implant companies you see in the journals and at meetings. For example, at the 2008 Greater New York Dental Meeting, there were many implant companies and implant related products to see there. There is an obvious increase in their presence, and this is encouraging since the meeting is mostly a general dental-based meeting. This is certainly a sign of where the implant market is going, as it should. The amount of edentulism in this country is high and people are living longer. The bottom line is that a dental implant offers the best alternative to replace missing teeth and as dentists we can offer that opportunity to our patients.
A clinician really needs to set apart marketing hype from the science of what a product offers. Doing this requires a little research and knowledge of what an implant offers in design for instance, or what a membrane offers to the surrounding tissue and how it handles. For instance the implant I have used for the past 10 years is made by BioHorizons. I like the fact that they have a square-shaped thread that allows for in­creased surface area and that it also comes with a stock abutment, which can be used much of the time. Each implant company offers different design features and nuances that make their product unique. It is up to the clinician to research products and decide what works best for them.

Dr. Adams: How do you get your pa­tients to accept treatment plans which include implants with the associated higher fees?

Dr. Tischler: I start with the awareness that a large portion of the US adult population is missing teeth. I am also knowledgeable that dental implants are the best way to replace missing teeth. Understanding these 2 facts, I basically present what is ideal with respect to implant treatment and accept the percentage of people that can find a way to afford this higher level of care.
I also present alternative plans for patients with regards to implant plans. Often alternative plans include building towards ideal plans with removable implant supported appliances. Over time these removable implant supported appliances can be converted to a fixed prosthesis with additional implants being added for support. In my practice I offer the services of various finance companies such as Capital One and CareCredit, to assist my patients. These financial companies allow me to offer financing without personally taking a risk. I feel the administrative fees these companies charge are outweighed by the convenience to the patient and in­creased acceptance of plans we see.
When it comes to a patient actually accepting implant treatment recommended, it is directly related to the clinician’s confidence in their plan and conviction that what they are presenting is right for the patient. A pa­tient makes large decisions such as an implant treatment plan based on many factors. These factors include, trust in the clinician, the reputation of the practice, feeling comfortable in a dental facility, the marketing and website they have seen, communications from the doctor and staff, and more. It is not just one thing that seals the deal.
In the end I feel the overriding driving factor is a clinician’s commitment to ideal care from dental implants for their patients that drives the many factors involved with creating a successful implant practice. That belief system will energize many things to happen. Unless the clinicians educate themselves or experience the benefits of dental implant services, it will be difficult to convey this with conviction.

Dr. Adams: Why is bone grafting such an important topic for you?

Cross-sectional view of CBCT showing implant placement in relation to tooth position and final prosthetic end result. A traditional radiograph will not show this buccal and lingual perspective. Cross-sectional view showing 3-mm one-piece Biohorizons implant to replace maxillary lateral incisor. One-piece 3-mm implants allow for placement in minimal buccal/lingual bone.

Dr. Tischler: The importance of bone in relationship to the final dental implant prosthesis cannot be overemphasized. It is imperative for any clinician involved with dental implants to understand that unless bone is in a position to support a dental implant, the implant to crown ratio, implant aesthetics, soft tissue around implants, occlusal position, and implant angulation will be affected. These are the most important aspects related to the success of implant treatment.
The status of bone supporting a dental implant should be considered during the treatment planning phase. This can be best done through utilizing CT. To place an implant in a compromised position because “the bone is there” is not justified. The present bone grafting science allows for highly predictable growth of bone. Once a prosthetic end result is determined, bone can be grafted to fulfill that desired position. General dentists extract around 22 million teeth a year according to a recent ADA survey. It has been extrapolated in the literature that only 2% of extraction sites are being grafted. General dentists are not grafting extraction sites. Also in the literature over and over again, it has been proven that once a tooth is ex­tracted, a patient will lose bone in both height and width. Through grafting an extraction site, the bone can be preserved for future implant placement or at least for pontic site development.
Whenever I lecture on dental implants, I include information on bone grafting because of the integral relationship that exists. It is a package deal between understanding dental implant science and bone grafting. They cannot be separated. I would even go one step further that to really tie everything together, soft tissue fundamental principles also need to be understood. What good is a dental implant without healthy surrounding soft tissue? This becomes even more crucial in the aesthetic zone with reference to correct papillae formation since bone supports the soft tissue. I feel that any adjunctive knowledge related to dental implant treatment is important in order to tie it all together and create implant treatment success. Implant dentistry in general, is a multidisciplinary treatment modality. The disciplines involved include biomechanics, pharmacology, cosmetic dentistry, radiology, prosthetic dentistry, anatomy, physiology, and psychology. Psychology might be one of the most important especially when you deal with larger cases that require patient compliance over a long period of time.
One more area of bone grafting that is important for every dentist to understand is sinus grafting. With the posterior maxilla often edentulous because of greater forces and weaker bone, it is important for dentists to know that this region can be predictably augmented for placement of dental implants. This can be performed through various techniques, but in the end a patient has an implant supported prosthesis that outperforms a removable prosthesis on every level. Why shouldn’t a dentist let their patient know this fact? This is just another example of why every dentist should understand the science of implant dentistry and bone grafting.

Dr. Adams: What are your recommendations to your fellow general dentist colleagues with regards to implementing implant dental procedures in their practice?

Dr. Tischler: Considering the substantiated need for dental implant services and future growth of implants in the dental industry, every general dentist should have a firm grasp of this discipline. The increase in needed implant services in the future is only going to increase. I strongly recommend for every clinician to embrace this discipline, even if only to be able to converse intelligently with his or her patients. For colleagues that wish to further their involvement in implant surgery, start with introductory courses to get the ball rolling. Build a foundation from the ground up and find your comfort level. Take courses that allow you to do actual surgical procedures under the guise of experts. If you choose as a general dentist to take on surgery, then allow at least a year or so to build the needed skills and when you are ready start with simple procedures in your practice. It is a multidisciplinary area of dentistry and the learning curve is steep. If you respect that, and are patient, it will happen.
Get involved with implant organizations, study groups, and respected train­ing programs. Get your staff involved as well, because they can carry your message. Realize that whatever you do will be held up to the standard of care in the profession, so make sure you dot every i and cross every t. One of the most important things to do as an implant restorative dentist is to communicate with your surgeon clearly and your laboratory clearly and build a team approach. Enjoy every aspect of implant treatment, but be prepared to deal with problems that will arise. Relish the opportunity to provide such an outstanding service for your patients and be ready to enter a whole new world of dentistry.

Dr. Michael Tischler is a general dentist in private practice in Woodstock, NY. He is a Diplomate of the American Board of Oral Implantology Implant Dentistry, a Diplomate and Fellow of the International Congress of Oral Implantologists, a Fellow of the American Academy of Implant Dentistry, and a Fellow and graduate of the Misch International Institute. He is on the Dental Advisory Board for Dentistry Today and on the Editorial Advisory Board for the Journal of Implant and Advanced Clinical Dentistry. He has published many articles in various dental journals and lectures internationally on the principles of implant dentistry and bone grafting. He is the director of implant education for Microdental Laboratories and is also on the Biohorizons educational speaker’s panel. He offers in-office courses at his teaching facility in Woodstock many times during the year and has a popular instructional DVD available that covers the principles of implant dentistry and bone grafting. He can be reached at (845) 679-3706 or by visiting tischlerdental.com.

Disclosure: Dr. Tischler receives and honorarium as an educator presenting for BioHorizons.