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exhibitors16 Greater New York Dental Meeting — Nov. 28, 2012 By Michael C. DiTolla, DDS, FAGD n In an effort to increase the indi- cations for BruxZir® Solid Zirconia crowns, the research and develop- ment department at Glidewell Labo- ratories is working to increase the translucency of this monolithic zirco- nia material. While the dental laboratory is not yet to the point of being able to do veneers, anterior BruxZir crowns are starting to come into their own. In Part II of this photo essay, the reversepreparationtechniqueisused to prep tooth #8 (a natural, endodonti- cally treated tooth) and #9 (a failing PFM) for BruxZir crowns. Fig. 1 I use the 801-021 round diamond bur from the Reverse Preparation Set (Axis Dental) to cut a half-circle into the gingival third of the tooth. This half-circle is the formation for the perfect margin. Fig. 2 I make my next depth cut to ensure adequate incisal reduction. I use the MADC-020 bur (Axis Dental) to place 2 mm depth cuts in the incisal edge of #8 to give the technician a good oppor- tunity to build an esthetic, strong incisal edge. Icompletethepreparationsequence using the MADC-015 (Axis Dental), 856-025 (Axis Dental) and Alpen 379- 023 burs (Coltène/Whaledent). Fig. 3 The next step of the reverse prepa- ration technique is to place the #2E Ultrapak top cord (Ultradent). Pack- ing this second cord can be difficult; you can’t floss it into place interproxi- mally like you can with the first cord because doing so would disrupt the bottom cord, which we want to stay firmly planted at the base of the sul- cus. Fig. 4 Once the top cord is in place, you get one last look at your margin. I am not entirely happy with what I see because the shape of my margin does not match the contour of the gingiva. I prepped the margin with a super coarse 856-025 bur, which left little chips, so I use my fine grit 856-025 bur to get rid of that choppiness. After placing two ROEKO Comprecap Anatomic compression caps (Coltène/ Whaledent)foreightto10minutes,we can remove the top cord and take the impressions. Fig. 5 The patient returns after five days for tempremovalandfinalBruxZircrown try-in. The BruxZir crowns fit well, so it is time to start the cementation procedure. Zirconia crowns are susceptible to salivary contamination when they are tried in the mouth. Fortunately, Ivoclean™ (Ivoclar Vivadent) was released earlier this year, specifically forthepurposeofcleaningoutrestora- tions prior to bonding or cementation. I place a couple drops in both of the crowns. The drops will stay in place for 20 seconds before being rinsed away. Ceramir® (Doxa Dental), which contains the same phosphate groups that bond to zirconia, can now be used to cement the BruxZir crowns. Fig. 6 Here are the cemented final BruxZir crowns on #8 and #9. I’m not suggest- ing you switch to this material for all of your anterior crowns. Unless you see the patient has broken other resto- rations or shows higher-than-average wear, you may be better off sticking with IPS e.max® (Ivoclar Vivadent) for this type of situation. We are getting closer, however, to BruxZir Solid Zirconia becoming a go-to anterior crown and bridge mate- rial. The pursuit of BruxZir anterior esthetics: part 2 5 Fig. 5 5 Fig. 3 5 Fig. 4 5 Fig. 25 Fig. 1 (Photos/Provided by Glidewell Laboratories) 5 Fig. 6 About the author Michael DiTolla, DDS, FAGD, gradu- ated from the University of the Pacific School of Dentistry and was awardedhisfellow- ship in the Acad- emy of General Dentistry in 1995. In 2001, he became director of clinical research and education at Glidewell Laboratory.DiTollaiseditorinchieffor ChairsideMagazine,hasamonthlycol- umn on restorative dentistry in Dental Economics and has been lecturing on restorativedentistrytopicssince1995. As a self-proclaimed “average dentist,” he has created techniques that give him great restorative results with a very average set of hands. His mission is to share these techniques with den- tists to help them improve their preps, impressions and restorations. Here at the GNYDM For more information on BruxZir Solid Zirconia crowns and bridges, stop by the Glidewell Laboratories booth, No. 4400. To view a live video of this case, visit the video gallery at www. glidewelldental.com.