Dentistry Today is pleased to present an interview with Dr. Michael Koczarski, who is recognized as one of the nation’s leading aesthetic dentists. He is a mentor, teacher, and lecturer who has been published extensively in a variety of dental journals. He also serves as editor of the Journal of the American Academy of Cosmetic Dentistry.
DT: Even though direct resin restorations are a very common procedure, they are not always as simple as we might think. Tell us about some of the challenges in treating patients using these materials.
ARE YOU INTERESTED IN VIEWING THE ENTIRE PROGRAM?
Quicktime video player required to view. Download now.
Dr. Koczarski: With a direct restoration, the doctor has to create the exact color and tooth shape with the patient right there in the chair. The challenge for practitioners today, despite all the technological advances, is that the patient’s dental IQ and expectations have risen, due in large part to extensive coverage in the media. It is necessary to make our work very realistic, understanding that in the end we are working to fulfill our patient’s desires.
Sometimes our patients desire aesthetics that may be unattainable. Therefore, it is important to know what our patient’s expectations are before beginning any procedure. They might bring in full-face photos showing a dentist how they want to look, but they may really be seeing the whole face and not just focused on their teeth. The challenge for a dentist is to discover what they want and to help guide them to an end result that is both realistic and achievable. If you can’t deliver what they want, then you have to make sure that you tell them in advance what it is you can or cannot realistically do. The zone of lifelike aesthetics can vary from patient to patient. Is it a zone of about 3 feet away, or is it 6 inches away? And of course as it gets closer, the demands to satisfy a patient’s expectations become much greater.
Even though there are advanced materials available today that can make a restoration more lifelike than ever before, we still have to be able to create it to make it a reality. That is a tough job to do at times. Direct resin veneers are a complex procedure and it’s important not to attempt this as your first work with composite resin restorations. One must understand the anatomy and try to build the smile one tooth at a time. Also, preoperative management of the case is the key.
DT: Would you demonstrate how you would handle an aesthetic veneer case utilizing direct resin composite?
Figure 1. Preoperative full-smile.
Figure 2. Before smile; 1:2 photo showing diastemas.
Figure 3. Diagnostic wax-up showing diastema closures and added length.
Figure 4. Preoperative stint tried in. It will be used as guide to locate proximal contacts and to define length.
Figure 5. Venus (Heraeus Kulzer) shade guide with œrecipe” to create the desired shades.
Figure 6. Preoperative model showing “high” spots where enamel was removed to create the ideal wax up shown in Figure No. 3.
Dr. Koczarski: Sure! The case that I want to share with you is a challenging one (Figure 1). Let’s first look at teeth Nos. 6 to 11 (Figure 2). Diastemas are present on the mesial Nos. 6 and 11, and Nos. 7 to 10 are slightly short with No. 10 protruded out a little facially, requiring that we will need to recontour this tooth. The color adaptive matrix of the composite resin that we will use for this case (Venus [Heraeus Kulzer]) is made to blend in with the dentition effectively and to mimic nature. I will prepare the teeth, taking away the high points of Nos. 7 and 10 while blending the facials of Nos. 8 and 9. Then, I will build the composite veneer on tooth No. 8 alone, followed by No. 9. Once Nos. 8 and 9 are completed, I will complete Nos. 7 and 6, and then Nos. 10 and 11.
Previously in the dental laboratory, a diagnostic wax-up was created for teeth Nos. 6 to 11 (Figure 3). A lingual silicone putty matrix was fabricated using the diagnostic model (Figure 4). This is an important step because this stent will be placed directly into the patient’s mouth to serve as a guide for our composite build-ups.
Laser will be used to trim the soft tissue and minimize any bleeding to keep it under control. We don’t intend to change the overall shade of this patient. In this case, we just plan to blend the restorations in with the surrounding dentition. This patient’s teeth blend in well with shade SB1 and a transition shade of T2. On the backside of the shade guide you’ll find your recipe (Figure 5). With this shade guide (Venus 2-Layer Shade System [Heraeus Kulzer]), SB1 includes: SBO (dentin shade), SB1 (enamel shade), T1 (transition shade), and T2 (topcoat for blending). We need to back the lingual side with SBO to block the light transmission and create an opaque effect. If just SB1 was used, you would have translucency that ends up looking gray. To confirm the shade selection, I apply a thin layer of SB1 enamel and T2 on an unetched and unbonded tooth, and then light-cure the materials to confirm the shade selection. This is a crucial step to do before proceeding on to the preparation phase.
After anesthetizing teeth Nos. 6 to 11, the soft tissue is trimmed to raise the right side to match the left. In the mock-up model (Figure 6), you can see that the dental technician previously marked teeth Nos. 7 and 10 in red to show which parts of them are protruding out too far facially. To blend and build the composite restorations, a little bit more of the facial and distal tooth structure will need to be removed in preparing teeth Nos. 7 and 10. Laser is also used to trim the soft tissue to raise the heights of contours of Nos. 6 and 8 so the result will match Nos. 9 to 11 (Figure 7). By using a diode laser, tissue can be trimmed the same day that we do the bonding steps, since bleeding is very limited and any potential contamination can be controlled. At this stage, it is important to stop trimming and directly face the patient to ensure that the final contours in the soft tissue are symmetrical.
Figure 7. Trimming the soft tissue with a diode laser (Odyssey [Ivoclar Vivadent]).
Figure 8. Stent being used to establish proper incisal length.
Figure 9. Matrix in place to isolate tooth No. 9 to keep bonding resin from contaminating adjacent teeth.
Figure 10. Finishing the proximal contact with Epitex (GC America) finishing strips
Figure 11. Final finishing of case, one-week post-op.
|Figure 12. Postoperative full-smile.|
It is important to use the matrix as your guide in building each tooth, using a flat bladed instrument to pack it like putty. Packing it well will help eliminate the creation of any voids in the composite resin material. Keep in mind the shape of your tooth, trimming off any excess material as you build. Be aware that if too much T1 is used, there won’t be enough room for the T2 topcoat and the tooth will end up looking gray.
The matrix is removed and we check for any lingual voids. A flowable composite such as Venus Flow (Heraeus Kulzer) can be used to fill any defects. Next, the composite is completely contoured and finished, but it is not polished yet. If you notice any seams in the composite material, go ahead and etch and rebond, adding a little more composite material. To create ideal contouring, I also use a sand disc on the facial. Check the size, length, and width of the tooth using your putty matrix as a guide.
To recap what I did on tooth No. 8: I used SBO shade to build the incisal length, the mesial and distal aspects, and the lingual one-half of the tooth; next I used SB1 to build the facial side; and then I used a thin layer of T2 on the incisal edge and entire facial surface. Again, I recommend that you build the teeth in these cases separately. It is a tedious process, but using the stint helps you maintain control of both the contours and contacts.
Using mylar strips (Figure 9), we now isolate tooth No. 9 and totally etch and bond the surface without touching teeth Nos. 8 and 10. I proceed by building the composite ve-neer on No. 9, letting the teeth touch with positive contact. Then I do a”Mopper Pop” using a half Hollenback instrument to break them apart once completed. I build the lingual half of our contact on No. 9 in SBO because I want it to be opaque enough to block light transmissions through the contact area. Otherwise it will look like a gray void. I continue to add SBO material interproximally to touch the mesial of No. 8. I tuck this material into the mesial to hide any black triangles and I add a little more into the incisal so there will not be a void. I use a little bit of rolled-up T2 to apply to the lingual half of the incisal edge area to give us our incisal translucency. I place a top layer of SB1 and then a final top layer of SB2 to help it blend into the gingival third of the tooth. Due to the color adaptive properties of this particular composite, I can back a more transparent color with a more opaque color. The final top layer is comprised of shade T2. Using a plastic filling instrument (PFI) the material is molded to form with final shaping and positioning with a sable brush. Again, we have built up the mesial of No. 9 to kiss up against No. 8. I place the matrix in the mouth and check the contours and shape again. I take a half Hollenback and do a œMopper Pop” (Figure 10) to break the 2 teeth apart, and then run a finishing strip between them to make sure everything is finished properly. These 2 teeth are now done except for a final polish. I then follow the same steps to create veneers on teeth Nos. 6, 7, 10, and 11 individually. ItÃs a little tedious, but it is the best way to stay in control and to accurately create the final form/shape of the teeth, creating nice proximal contacts throughout.
At this point, it’s always best to work from the straight-on facial position for final contours, shaping, and symmetry. I use a flame-shaped 40-µm diamond for final contours and shaping. Occlusion and canine guidance is checked in all excursive movements, and the final finishing and polishing is performed. It’s important to polish carefully, using slow speed, light pressure, and plenty of water (Figure 11).
DT: Why use different opacities when building up a tooth? Aren’t the newest versions of today’s composites good enough to use only one shade?
Dr. Koczarski: You can try to pick one shade to match the shade of a tooth. However, if you want to build a more anatomically correct tooth, you need to build a tooth like a tooth has been designed and built by nature. A natural tooth has a more opaque dentin core, and a more transparent and yet brighter enamel area. Therefore, we try to rebuild those structures into the restoration to mimic nature. This will give you a more natural look and a better matching of the transparencies of the tooth.
There is also a problem that un-der different types of lighting, the restorations can appear to be different. If you get dressed one morning and think your shirt and pants match, then you walk out of the closet into another kind of light, you may decide that they donÃt match after all. We have this same problem when trying to match porcelains or composites to the natural enamel under different lighting. The better you are at matching the translucencies of a tooth, the better your blend to natural tooth color will be as well.
DT: Do you ever custom stain composite resin restorations?
Dr. Koczarski: Yes, I do. In fact the best way to hide or blend a direct composite case to the adjacent tooth structure is to make sure that you mimic and copy things like hypocalcifications, fractures, stained areas, etc. The best way to place custom tinting, staining, and characterization is to “trap” them underneath the final top layer of T2. I often use the Kerr Kolor Plus kit. Sometimes I’ll dilute and mix the colors. For example, if I’m building the distal half of No. 8, and the mesial half has some hypocalcified spots, I’ll make sure I add hypocalcifications to the distal aspect when I’m creating it. By building it in composite and then trapping it inside this skim-coat layer, it appears to be within the tooth, allowing it look like a natural tooth. It will also last longer when it is layered into the restoration in this way. The trick is to create fracture lines, hypocalcified areas, and enamel translucencies with tinting and colors layered under the skim coat layer.
DT: What is your opinion on direct versus indirect restorations?
Dr. Koczarski: Of course, this case is about direct restorations. When this procedure can be done, the major advantage is that it can be minimally invasive since we are not cutting away much tooth structure. Direct composite resins can be very aesthetic as well. This patient’s case ended up looking very nice (Figure 12). However, it’s a lot of work and chair time for me as a dentist, and sometimes it’s hard to charge enough for the time needed to do this kind of case right.
If we had wanted to do a faster technique that involved less chair time, I could have treated this patient with indirect, lab-fabricated veneers, with the patient coming back for a second visit to bond them into place. But, to have done that, I would have been more invasive and there would have been the additional lab costs involved.
There are also the pros and cons regarding the issues of longevity. Typically, a porcelain restoration can last twice as long as a composite restoration.
So, there are pros and cons of both techniques. Much depends on the abilities and artistry of the dentist. Do you want to build veneers that way? Do you have a patient that is willing to sit that long to have it done? Do they want that because they want minimally invasive treatment, or do they simply want a procedure with fewer visits? It just depends. I think the basic and un-derlying theme is that direct composite veneers provide us with a way to put back what was missing or was never there without being too invasive. It allows us to enhance someone’s smile or the strength of their enamel by adding something back. It is using microdentistry to achieve a great result.
DT: Do you always use a wax-up on anterior cases like this, or is there another way to accomplish that?
Dr. Koczarski: If it is more than 2 teeth I always use a wax-up. To me, you’re just flying in the dark without one. And like we mentioned earlier, as you build these teeth you need to stay in control of the transparencies and translucencies that you are trying to build into final form. You need to know where you are going so that you do not end up with a final result that may be too long or too bulky.
I use a wax-up to help eliminate guesswork and to guide me through the building process. As you saw with this case, the lingual putty matrix stent really helped in building the teeth properly.
DT: The 2-shade technique: anatomical and shaded. What’s the difference and when do you use one versus the other?
Dr. Koczarski: In dental school I was taught how to use a shaded technique. I would select the shade of the tooth, pick a composite shade, and then build the tooth. That is building the tooth based on the shade of the overall picture of the tooth.
The anatomical technique is looking at the dentin shade and the enamel shade, and the 2 combined. For example, a darker dentin and a brighter enamel combined looks like an A2. If I have someone whose teeth are more opaque, or someone who has bleached their teeth and their teeth are high in value, the shaded technique is a good way to build the tooth color.
If the patient has teeth that have a lot more depth of color with more transparency to them, like in the C shade range€or if you have tetracycline staining—then I will use the anatomical technique. If the end result desired is a C3, I’ll pick a C5 darker opaque dentin or I may use stain and opaquers to make it look even darker. Then, I will layer a more translucent blue or gray colored composite on. The result will be a C3 with the depth of color coming through. So, I use 2 techniques: the anatomical technique with the more transparent teeth and in the posterior quadrants; and the shaded technique with bleached or lighter teeth.
DT: Please recap how you use the clear composite as a final layer.
Dr. Koczarski: I use it as a skim coating to try and hide the seams from restoration to natural tooth structure. I learned to use a very thin layer of a transparent color to hide the transition of composite into tooth structure. I used to do a single 45° bevel to hide my transition from composite to the tooth structure. Now I place 2 bevels: a 45° bevel followed by a much longer and uneven bevel. As composite is built up to its completed form, I do so, leaving room for the final thin layer, spreading it out over the composite and over the longer skimmed-out bevel. It is important to keep that skim layer to less than 0.5 mm in thickness. If it is applied too thickly, it will start to look gray and will lower the overall value of the restoration. With composite resins, you also have to build the tooth to final form. You cannot overbuild the tooth and then cut it back. I expect this result to last up to 7 to 10 years with this conservative noninvasive approach. Porcelain may last longer, but it’s much more aggressive to the teeth.
Creating a beautiful smile is more than restoring a single tooth back to its proper form. One must take into account the entire aesthetic zone, along with the mechanics of restoring the teeth to proper form and function. To make this effort even more challenging, the clinician is in full control and completely accountable for making the direct composite resin restorations from which the smile is created. Patients usually won’t critique the aesthetics of a posterior direct resin, but once we move into the visible smile (along with the fact that most cosmetic procedures are patient desire- and want-driven) we must be able to deliver what the patient expects.
Preplanning the case and avoiding the œprep and pray” approach to the smile-design process is the cornerstone of success. Utilizing tools for the creation of the restorations, such as a preoperative wax-up and silicone putty matrix, help the clinician break the procedure down to individual restorations that when created in harmony with the preoperative design or wax-up, will allow a final “smile design” to emerge with predictability without getting lost in the daunting task of creating the entire smile all at once.
Proper use of ideal composite materials adds the final touch on creating realistic results that even the most discerning patients demand. Layering colors, utilizing differing opacities and translucencies within the restorative process, is a must. Having a “recipe” to follow simplifies the process and gives the clinician confidence that the final result will have that realistic look. All in all, the easiest way to handle a challenging case is to break it down into smaller and more manageable increments in order to ensure a predictable outcome.
Disclosure: Dr. Koczarski has no financial interest in any of the companies mentioned in this article.