
Veneers are a conservative way to offer patients exquisite esthetics. Keeping veneer provisionals in place is one of the challenges to achieving these results. It seems like either they are constantly coming off to the point that both I and my patients are frustrated. Alternatively if the patient comes in for the seat appointment and the veneer provisionals have been in place since the preparation I wonder how much work it will be to remove them. For years I searched fort a technique that would allow the provisionals to stay in reliably and come off easily for the seat appointment.
Several years ago I found a technique that achieves just those two goals. I have been using it ever since with great success. Before seating the provisionals air abrade the internal surface with 50 micron aluminum oxide. This will encourage the resin cement to attach to the bisacryl. With the provisionals ready to go, isolate the prepared teeth. Using phosphoric acid spot etch the labial surface of the teeth. You want this spot to be approximately 2-3mm in diameter. I place it midway on the labial surface between the mesial and distal and cervical and incisal of the prep. I leave the etchant in place for twenty-five seconds and then rinse thoroughly, followed by air drying. Next I paint flowable composite of the same shade as the bisacryl onto the air abraded surface of the provisional and seat against the preps.
Using a microbrush I clean off all of the excess flowable that has been expressed at the margins. Once I have adequately cleaned the uncured flowable we light cure all of the surfaces to fully cure the resin. Once cured I can use a scaler, #12 blade or other tools to check and clean the margins and remove the thin layers of cured excess. I have found this technique highly effective whether the are of the prep I am etching is predominantly enamel or dentin. When the patients return for their seat appointment I cut a slot into the facial of the bisacryl over each tooth without penetrating to the tooth surface. This allows me to place the blade of a plastic instrument into the slot and twist gently to separate the flowable. Once it has been freed from every prep the provisional can be removed. I utilize a friction grip brownie running at less slow speed to remove any flowable that remains over the small area where the tooth was etched.
- You can substitute a self etching one step dentin adhesive for the phosphoric acid. KEEP the spot size the same 2-3mm and no larger.
- You can substitute the resin of a fourth generation dentin adhesive for the flowable. DO NOT use the primer first.
- You can substitute any light cure veneer cement for the flowable. DO NOT use a dentin adhesive.
So…don’t…use dentin adhesive? :D
Merry Christmas, Lee!
CARL
Don’t use dentin adhesive if you have spot etched with phosphoric acid. The problem with the adhesive is the primer, if you etch, prime and bond then removal is a nightmare. We want to use parts of the system like etching and then resin ( flowable or the resin of something like Optibond FL) but NO primer in between.
Once I have adequately cleaned the uncured flowable we air abrade all of the surfaces to fully cure the resin?? Air abrade or did you mean light cure?
Tere,
Thanks for catching that, yes I meant light cure!
Do you use the same technique for single tooth veneer temporization as well?
Single Tooth Veneer Provisionals can be very complicated to keep in place. My preference would be to use a Shrink Wrap Provisional Technique, but if I were doing indirect and cementing I would use a spot etch flowable cementation protocol.
Lee
Thank you!!
Im confused, so after spot etching, you don’t use any type of bond on the tooth? so what is the purpose of the etch then since the flowable wont be bonding to the etched part of the tooth anyways? we don’t have any primer + bond systems anymore. everything is one step minus the etch.
thanks
The etchant is etching the surface of the prep. Flowable is an unfilled, or very low filled resin, much like the resin component of a dentin adhesive. Without the primer portion you will get a bond to the enamel or dentin of the prep, but no hybrid zone development. and lower bond strengths. It increases the retention of the temporaries, but still allows removal.
Hi,
Will this work if there is an existing facial composite in the prepped tooth?
Yes, if the composite has been int he tooth awhile follow the technique without change. If you have just placed a composite to do a buildup or repair, I would place a small amount of lubricant (vaseline, lubricoat) on the composite before even making the bisacryl shell as they can bond together.
Hello,
Thanks for sharing your method! When removing the provisionals, which way do you cut the slots on each tooth (vertical or horizontal)? If vertical, do you need to go over the incisal edge, as there likely is flowable on the lingual of the tooth as well? I am going to try this method, however, I am concerned about how difficult it may be to remove the flowable (does it all come off easily or is a lot of time needed to clean off the flowable near the margins)? Thank you!
I typically, use a 330 carbide, dry and running at slow speed on my speed reduction electric. i do not go through the bisacryl, just create a bunch of notches and then use a crown remover to lightly twist. I do go over the incisal edge if I prepped it and have solid bisacryl. It s not difficult at all to remove the resin, just never use a dentin adhesive!
Any ideas on if this technique will work if I want to temporarily bond lithium disilicate? I have a very specific case I’m thinking about doing this.