When you talk to dentists about the procedures they are fearful of, seating porcelain veneers comes up frequently as one of the most anxiety producing.
The following is a continuation from Part I of the steps in the veneer seating process.
Step 4: Know the materials used. It is absolutely essential to know what materials your technician uses and how they use them. For instance with this particular patient, my lab technician did not acid-etch the veneers before sending them back to me, which required that I etch the surface. Different materials require different etching times so you must know the specifics for each case. In most instances your lab will have already acid etched the restorations but you will need to clean them following your try-in. I typically clean using distilled water in an ultrasonic cleaner for five minutes. Following the cleaning I also silanate the restorations for 60 seconds prior to enhance the resin ceramic bond.
Step 5: Apply retraction cord: When it comes to anterior teeth, I don’t use a rubber dam for veneer placement, I use retraction cord. If the margins are supragingival the cord is not necessary, but if the margins are equigingival, or subgingival, I place an Ultradent 00 cord to avoid contamination during the bonding. I often wait until after the retraction cord is placed to perform the air-abrasion as it is easier with the cord in place.
Step 6: Apply desensitizer and adhesive. I use a total etch adhesive, Single Bond Plus from 3M, so I start by acid etching with 32 percent phosphoric acid for 15 seconds, followed by rinsing and lightly drying with clean air from an Adec air dryer. I then apply Gluma Desensitizer from Kulzer for its desensitizing and antibacterial properties. After lightly drying the Gluma, I paint on two layers of adhesive; I don’t pre-cure my adhesive when doing veneers. I only etch and apply adhesive to the number of teeth I am planning on seating, generally the two centrals first, followed by the lateral and canine on one side, then the other.
Step 7: Go back to the veneers. Now that the teeth are ready, it’s time to go back to the veneers which have been cleaned and silanated, now I paint the Single Bond Plus adhesive on the inside of each veneer, dry it and apply the cement chosen.
Step 8: Place veneers. I then bring the two central veneers to the mouth and place them. After I have placed them correctly and am holding them with pressure from the facial and incisal, I have the assistant “tack cure” from the lingual of the incisal edge. I then clean the margins with a brush and explorer prior to final curing. The only problem with this part of the process is the potential for oxygen inhibition to prevent a complete cure of the margin, the risk of oxygen inhibition can be eliminated by leaving a small excess of cement at the margin instead of cleaning it all, or cleaning completely but painting glycerin over the margin prior to curing the cement. Then light cure 30 seconds from the facial and lingual with a high intensity curing light.
Now that the two centrals are placed, I finish them completely before moving on to the adjacent teeth. The laterals and canine on one side are then completed following the same steps.
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