Photo Essay: Utilizing No-Prep Veneers with Zirconia Crowns to Complete a Smile
Chairside Magazine: Volume 9, Issue 1
article by Michael C. DiTolla, DDS, FAGD
These maxillary anterior infiltrations can be exquisitely sensitive for many patients, so I just talk to my assistant to distract the patient, and let the computer do its thing.
Figure 1: This patient came in hoping to make an esthetic improvement in her smile. Because of the amount of wear and interproximal decay on the four anterior teeth, we decided to use zirconia-based crowns to restore #7–10. She had several existing PFMs in her mouth, two of which had already been broken.
Figure 2: Because of the shade change that she desired, I also suggested some no-prep veneers adjacent to the four crowns. This always helps the crowns blend in better while allowing patients to choose nearly any shade they want. I will place them on teeth #5, #6, #11, #12 and #13. The other posterior teeth are PFMs.
Figure 3: In an attempt to always give the most painless injections possible, we begin by using the PF Lite Topical Anesthetic (Steven’s Pharmacy; Costa Mesa, Calif.). She wasn’t going to let an aphthous ulcer stop her from leaving with new temps!
Figure 4: The Wand® handpiece (Milestone Scientific; Livingston, N.J.) for the STA™ device (Milestone Scientific) allows me to give local anesthesia at the slowest possible computer-controlled rate without even having to think about it. These maxillary anterior infiltrations can be exquisitely sensitive for many patients, so I just talk to my assistant to distract the patient, and let the computer do its thing.
Figure 5: To break the contacts between #8 and #9, I am going to use the 856-025 bur (Axis Dental; Coppell, Texas) from the Reverse Prep Kit. This will allow me to break the contact and begin the interproximal margin formation. I can also do this between #7 and #8, and between #9 and #10. I love doing as much as I can with the 856-025.
Figure 6: Here is the 856-018 bur (Axis Dental) being used to break the contact between #10 and #11. Because we aren’t preparing #11, there is no way we can fit the larger 856-025 bur between these two teeth. Both burs are the same shape, the only difference being the diameter. Once the 018 fits through, the 025 can typically pass through as well.
Figure 7: Next, I will do the gingival margin preparation. Typically, I would have already placed a #00 Ultrapak® cord (Ultradent; South Jordan, Utah) in the sulcus, but I know I am not going to impress today, hence the lack of cord. On multiple-unit anterior cases, I rarely impress the day I prep. I will use the 801-023 bur (Axis Dental) to prep the facial and lingual gingival margins.
Figure 8: Here is a look at the BioTemps® (Glidewell Laboratories; Newport Beach, Calif.) from #7–10. They are splinted together for retention purposes. The patient loved how they looked, and if there is any doubt, you can make a putty-wash matrix of the BioTemps on the model, fill it with Luxatemp® Ultra (DMG America; Englewood, N.J.) and lock it onto the patient’s teeth for a preview.
Figure 9: When I measure the length of the central incisors on the BioTemps, they are 10.5 mm from the mid-tooth gingival margin to the incisal edge. That is probably the most common length we see for central incisors, and we will use that number for deciding how much to reduce the incisal edges of the teeth.
Figure 10: With the calipers at 10.5 mm, I can see that the length of #8 is about 9.5 mm. Because we typically reduce 2 mm for anterior teeth and the patient has already reduced 1 mm with wear, I only need to reduce an additional 1 mm from this tooth. Tooth #9 is 8.5 mm long, so I don’t need to reduce anything on this tooth. The laterals will each need 1 mm of reduction as well.
Figure 11: This depth cutter from the Reverse Prep Kit is self-limiting because of the shoulder at the end of the shank. I rest that against the incisal edge of the tooth and step on the rheostat. You can see the half-circle cut from the round bur at the gingival margin. Once the axial reduction is completed, it will be a perfect quarter-circle, aka a deep chamfer or shallow shoulder.
Figure 12: Here, I am using my 1 mm depth cutter to place my axial depth cut at the junction of the incisal third and middle thirds of the teeth. This depth cut is particularly helpful in anterior teeth to prevent final restorations that make patients look like a beaver (unless they are Canadian and request that!).
Figure 13: With all the depth cuts placed, we can now break out the 856-025 bur again and begin to blend them all. The act of blending helps the prep to take the proper shape and also helps to ensure adequate reduction, allowing your technicians to do the best job that they can.
Figure 14: The 379-023 football bur (Axis Dental) is used to reduce the lingual surface of the preps. In cases where the patient has a deep overbite, I find it difficult to visually gauge how much clearance I have created with my reduction, so I place a depth cut on the lingual to ensure I have reduced enough for that particular material.
Figure 15: At this point, the gross preparation steps are finished, and it is time to think about what I need to do to finish these preps. From looking at the radiographs, I know that we have some interproximal lesions, and we can’t go much further until we clean those out and build them back up.
Figure 16: I like using Exposé® (Centrix; Shelton, Conn.) any time I am removing decay, especially in the vicinity of where I think a pulp horn might be located. I find it does a great job of identifying demineralized dentin. BONUS TIP: During endo, use it on the pulpal floor to help identify canal orifices that you are having a hard time finding.
Figure 17: I am removing the demineralized dentin with a #1 round bur in the latch attachment for my KaVo ELECTROtorque handpiece (KaVo USA; Charlotte, N.C.). Regardless of how slow you have it spin, it always has enough torque to remove tooth structure. Rinse, dry and restain with Exposé until you have removed the caries.
Figure 18: Interproximal buildups like the ones I am doing here are probably more accurately described as fillers rather than buildups. I always think of a buildup as providing retention for the crown, whereas in this case, these fillers are more to protect the pulp and eliminate prep undercuts, although they do provide a small amount of retention as well. I am using Vertise™ Flow (Kerr Corporation; Orange, Calif.).
Figure 19: Vertise Flow is a self-adhering, light-cure flowable composite. In other words, it’s a flowable composite with the self-etching bonding agent built into it. You simply express the Vertise Flow into the prep, and agitate it against the dentin for 15 seconds with the brush tip that’s at the end of the syringe. Cure that for 20 seconds, and then just add any additional material directly on top without agitating.
Figure 20: I am now using the 856-025F fine-grit diamond bur to smooth the Vertise Flow fillers that I placed in the preps. I find the self-adhering bond strength of Vertise Flow to be more than adequate for these types of interproximal fillers on anterior preps, but when doing a buildup on a posterior prep, I am going to do the self-etch (or etch-and-rinse) step separately so that I don’t lose the buildup when removing the temp.
Figure 21: Because I am not going to impress this today, I am done with the preps for this appointment, and now need to focus on the BioTemps. The first thing I want to do is confirm that I have a passive fit of the BioTemps. When I set them into place on the preps, I would like them to fall into place, and even be a little loose because we are going to reline them. Have the patient close during the BioTemps try-in to ensure they aren’t too far lingual.
Figure 22: My dental assistant then takes Luxatemp and injects the material into the BioTemps, seats them and has the patient close in order to get the bite correct now. Unfortunately, I have relined them before without checking the bite, and it results in a ton of grinding. If you have good marginal fit on the BioTemps, feel free to remove excess Luxatemp with an explorer; otherwise, leave it alone.
Figure 23: Once my assistant has finished contouring and polishing the gingival third of the BioTemps, they are ready to be cemented. But first, she has to place a coat of G5™ All-Purpose Desensitizer (Clinician’s Choice; New Milford, Conn.) on the preps and wait one minute for it to air dry. She does a second coat the same way, then places pre-knotted Glide® floss (Procter & Gamble; Cincinnati, Ohio) into each of the gingival embrasures, loads the BioTemps with TempBond® Clear™ (Kerr Corporation), and seats them.
Figure 24: The seated BioTemps after initial cement cleanup. Note the small open gingival embrasures that are visible. I blunted too many interdental papillae in my career from the prep appointment to the seat appointment, which doesn’t happen when we leave these open. It also allows the patient to swish with Tooth & Gums Tonic® (Dental Herb Company Inc.; Lancaster, N.H.) during these two weeks to improve tissue health.
The first thing I want to do is confirm that I have a passive fit of the BioTemps.
Figure 25: It has been two weeks, and the patient is back to finish the preps and get the impression. Because the temps have been in place for two weeks, I can see what the tissue has done and make any necessary prep changes. When I used to impress on the first appointment, the seat appointment had too many unwelcomed gingival surprises. Those surprises rarely happen with the extra appointment.
Figure 26: I can’t finalize my margin placement until I place my size #00 Ultrapak retraction cord. This will allow me to place the margins slightly subgingival without taking a bur subgingival. I find it easiest to use this #00 cord like dental floss and “floss” it into the interproximal areas to help hold it down in place. I then grab the two loose ends on the lingual and pull until the cord almost hits the facial of the preps.
Figure 27: I now use a straight (as opposed to off-angle), non-serrated cord packer to place the cord into the facial and lingual sulci. I trim the two loose ends on the lingual so that when the cord is packed, those ends are flush rather than being on top of each other. Because we are going to place another cord, I need that space.
Figure 28: With the #00 cord in place, I can now finish these preps with the 856-025F fine-grit bur. I turn the water off on my electric handpiece, take the speed down to 2,000 rpm, and smooth the gingival margins while slightly dropping them apically to the new gingival tissue level as a result of placing the #00 cord.
Figure 29: My assistant now places the top cord in the two-cord technique, a #2 Ultrapak cord (Ultradent). She can legally place both cords in our state, but I usually do the first one myself because it is part of the prep sequence. She then moistens and places ROEKO Comprecap Anatomic compression caps (Coltène/Whaledent; Cuyahoga Falls, Ohio) on the preps and has the patient bite down for eight to 10 minutes, at which time I get a text telling me they are ready.
Figure 30: The Anatomic Comprecaps are removed, and then the top cord (#2) is removed as I get ready to place the syringe material. Because the bottom cord (#00) stays in place during the two-cord technique, there should be no bleeding at this time, and the gingival margin of the preps should be visible. The two-cord technique takes a little more time, but is well worth it.
Figure 31: You can clearly see the prep margin and the wide-open sulcus. The two-cord technique allows you to get much more impression material subgingival; but, because the sulcular impression material ends up being nearly 1.5 mm long, I had to switch my Capture® VPS impression material (Glidewell Laboratories) from light body to medium body to keep it from tearing when I removed the impression.
Figure 32: Ah, the joys of a custom tray! Never having to bump into teeth, tori or arch-width issues, they allow you to use less impression material while getting a better impression. I know that I cheat because I practice inside a lab, so they are readily available, but if you have a way to make them, it’s hard to go back once you get spoiled by them!
Figure 33: That flange of purple impression material apical to the yellow is the gem of the Two-Cord Impression Technique: the impression of the root surface apical to the restorative margin. Not only does this show technicians exactly where the margin stops, but it also gives the emergence profile for them to match, which is so critical to having natural-looking anterior crowns.
Figure 34: My assistant is now taking the bite registration with Capture Hard Bite (Glidewell Laboratories). Remember that all the lab wants in a bite registration is the incisal third of the preps and the incisal third of the opposing teeth. We do not want or need the entire arch; in fact, the bite registration is more accurate for the anterior preps when there is no material between the unprepared teeth.
Figure 35: It’s the third appointment, and the tissue will not have changed because we didn’t make any modifications to the temps. This eliminates the issue I used to have with black triangles appearing at the seat appointment that weren’t there at the prep appointment. I have stopped trying to make the temps look perfect at the gingival embrasures, especially when it might come back to bite me.
Figure 36: I know of no better way to clean up preparations at the try-in appointment than the KaVo SONICflex Scaler (KaVo USA). It is a must for cases when Durelon™ (3M™ ESPE™; St. Paul, Minn.) is used as a temporary cement to ensure that the temps don’t come off over a holiday or a vacation. Regardless, we use the KaVo scaler on every case to remove all temporary cement, a common cause of restorations not seating completely.
Figure 37: The initial try-in of the restorations is done by my assistant while I am out of the room. I honestly don’t want to influence patients to accept something that they don’t necessarily love. My assistant comes and tells me if the patient likes them, and then I go in and try them in myself to get familiar with any path of insertion issues.
Figure 38: I always place #8 and #9 first, and in this case, I am using Ceramir® Crown & Bridge cement (Doxa Dental Inc.; Newport Beach, Calif.). Because the central incisors essentially can make or break the smile, I prefer not to have to deal with the lateral incisors or any possible contact issues. I will deal with those on the laterals once the centrals are cemented and cleaned up.
Figure 39: Fortunately, there were no issues with the laterals, which you would expect with crowns. The same cannot be said for the veneers; however, I am never surprised when veneers have contact issues. Once I bond a couple of veneers, I always try in the adjacent veneers again, especially with no-prep veneers. Often, I get away with it until I get to the veneer for the second bicuspid.
Figure 40: Once the crowns are on, it is time to place the no-prep veneers. I find that a surgical suction tip (with the suction on) is perhaps the most secure way to place these veneers. The sticky tips often seem to be feast or famine: I’ve had veneers fall off on their way to the mouth, and I have had veneers pull off as soon as I place them. All suction units are not created equal, so your mileage may vary.
Figure 41: I am using the light-cure clear shade veneer cement from the NX3 Nexus® system (Kerr Corporation). I set them into place with the suction tips, and then use two pinewood sticks to fully seat the veneer. One stick pushes the veneer onto the tooth from the facial, while the other pushes it to the gingival from the incisal. Try to use equal force on both sticks. Essentially, I try to slide it on at a 45-degree angle.
Figure 42: I quickly hit the gingival margin for two seconds, and then clean up the gelled cement around the gingival margin and, more importantly, in the interproximal embrasures. If resin cement is allowed to cure completely interproximally, the cleanup effort increases exponentially. Once I can pass a Thornton Bridge & Implant Cleaner (Thornton International Inc.; Norwalk, Conn.) through the interproximals, I know I am safe to cure the veneer completely.
Figure 43: Even if you are fastidious about cleaning the resin cement from the embrasures prior to curing, there is almost always at least some bonding agent that has cured between the teeth. A serrated strip, like this one from Axis Dental, is absolutely essential when seating veneers. If we were out of them on a given day, I would absolutely reschedule a veneer seating appointment.
Figure 44: Here is a good look at my favorite use for no-prep veneers. This is the patient after seating the crowns on #7–10, but without the veneers. It is definitely noticeable that the crowns are there. Sometimes it’s difficult to blend them to surrounding dentition when those teeth really don’t look good enough to match anyway. Without any more injections or prepping, no-prep veneers can help to finish off this smile.
Figure 45: With the no-prep veneers now seated on #5, #6, #11, #12 and #13, the smile looks more natural and complete. Now the only things that really stand out are the PFMs on teeth #4 and #14. We let the patient know that we can change those out if they ever start to bother her.
Figure 46: Right lateral smile shot of the completed case. Again, the no-prep veneers help create a smooth transition from anterior teeth to posterior teeth. Nearly all anterior restorations are larger facially than the teeth they are restoring. Dentists tend to underprepare in the name of conservatism, while technicians tend to overbuild crowns in the name of esthetics.
Figure 47: Left lateral smile shot of the completed case. When we underprepare and technicians overbuild, teeth get bigger; and no-prep veneers are an excellent way to compensate for that, while improving the shade, shape and buccal corridor of the smile as well. Next time you do a crown on just #8 or #9, have the lab make a no-prep veneer for you without even asking the patient. Seat the crown alone, then with the veneer to see the difference for yourself, and see what the patient thinks. You might be surprised by how much they like this idea!
Because the central incisors essentially can make or break the smile, I prefer not to have to deal with the lateral incisors or any possible contact issues.