Dear Dr. DiTolla,

Thanks for another great edition of Chairside^®! When the magazine arrived, we were all eager to see which GL we missed in the last photo hunt contest (of course, the one at the base of the palm tree in the center — we will settle for second place). Before I could turn around, my front desk staff was working hard on the new photo hunt, and she’s doing pretty good so far! I can honestly say this is the only magazine that I really read from cover to cover.

Clinical note: I have become a very big fan of the BruxZir^® crown. Any second molar crown in my practice gets BruxZir, along with some first molars (heavy grinders or previously chipped porcelain). I have found that many of the cases come back with a small rim around the margin, as if there was a minute bevel around the entire prep. Many times it is insignificant, but last week I had a case where I was able to feel a significant step/overhang that needed to be trimmed back. Is this a result of the processing nature of these crowns? I don’t seem to have the same issue with Prismatik CZ™ crowns.

Thanks once again for the great lessons of dentistry that I have put into my everyday practice.

– Robert M. Lieder, DDS
Baltimore, Md.

Dear Robert,

Thanks for the kind words about Chairside! Regarding BruxZir crowns, what you are seeing is a design issue in the software where it bulks up an otherwise thin margin to keep it from chipping during the milling process when a doctor has prepped a very fine feather-edge margin. This is one of the reasons why I like a deep chamfer margin; it designs better, mills better and is most likely going to be stronger.

– Mike

Dear Dr. DiTolla,

Is Silent Nite^® sl as comfortable to wear as a hard/soft nightguard? A patient said she needs a nightguard, and she snores at times. Which would be her choice? Could I just send you upper and lower models to make a Silent Nite sl? Can the patient just use the upper or lower part of the Silent Nite sl as an occlusal nightguard and also as an ortho retainer? Please reply as soon as possible, as there is an urgent decision to make. Thank you!

– Stephen C. Hsu, DMD
Fort Washington, Pa.

Dear Stephen,

Good questions! In my experience, the Silent Nite sl is the more comprehensive device because it stops snoring and bruxism. The upper and lower trays of the Silent Nite sl are made from the same material as the bite splints, so there really is no difference in comfort, save for the fact that the Silent Nite sl has an upper and a lower portion as opposed to a single-arch nightguard.

Unlike previous generations of Silent Nite appliances, with the Silent Nite sl, the patient can actually take it apart on their own and simply wear one half — although that would require the patient to correctly predict the nights on which they were going to snore so they could wear both.

To answer your final question: Yes, you can send us upper and lower models to fabricate the appliance; however, it is more helpful if we have a protrusive bite utilizing the sl-protrusion gauge, which you can get from our lab.

Hope that helps!

– Mike

Dear Dr. DiTolla,

I’m placing my first two minimal-prep veneers on tooth #7 and #10, with Captek™ PFMs (Argen; San Diego, Calif.) on tooth #8 and #9. Glidewell did the diagnostic wax-up and is now finishing it. Could you suggest, A to Z, the try-in and delivery of these veneers, including materials necessary? As these are minimal prep, please advise if I should use a bonding agent or straight cement, as well as the specific silane, acid and cements. Thank you.

– Lee G. Taylor, DDS
Havertown, Pa.

Dear Lee,

I would try in the units one at a time without any try-in cement to check marginal fit. I would try in the crowns on tooth #8 and #9 together to verify the contacts are correct and are not keeping them from seating. I would then load the veneers on tooth #7 and #10 with try-in cement to verify they will seat while tooth #8 and #9 are seated.

I always seat tooth #8 and #9 first, and since they are Captek crowns, I would use a resin-reinforced glass ionomer like RelyX™ Luting Plus cement (3M™ ESPE™; St. Paul, Minn.) or GC Fuji Plus™ (GC America; Alsip, Ill.). Once those have been cemented and the excess cement has been cleaned, it’s time to move on to the veneers.

You should rinse the water-soluble try-in paste out of the veneers for tooth #7 and #10, and then dry them to verify you can see the etched internal surface of the veneers. If you can’t, you should re-etch them with a 6 to 10 percent hydrofluoric acid for 60 seconds, and then rinse. You would then place the ceramic silane solution of your choice (Kerr Silane Primer [Kerr; Orange, Calif.], for example) and evaporate it after about 10 seconds. Place a thin layer of bonding agent (adhesive) from a two-bottle system (such as OptiBond^® [Kerr]) and air thin.

Because these are minimal-prep veneers, and by definition confined to the enamel, etch the enamel surface with your choice of phosphoric acid (I use Ultra-Etch^® [Ultradent; South Jordan, Utah]). Rinse after 15 seconds. We don’t need a dentin bonding agent, so I would use the same bonding agent we placed in the veneer. For me, it’s the adhesive from the two-bottle OptiBond system. Air thin that once you have brushed it onto the tooth, and load the veneers with your preferred resin cement. For me, that is the translucent shade of NX3 Nexus^® Third Generation light cure cement (Kerr). Seat one of the veneers by sliding it into place with facial and incisal pressure. Tack cure it for two to three seconds to get the cement to its gel stage, clean the excess, then finish curing and repeat for the other side.

– Mike

Dear Dr. DiTolla,

An old patient of mine appeared with an incisal angle fracture on the distal of tooth #8. He also has a large Class III filling on the mesial of #8. Tooth #9 is in good condition.

I would like to place two no-prep veneers on #8 and #9. How do you treat the old fillings that are in #8? They have been in place for many years. Is it best to take them out, and replace them with nice clean fillings? The reason I am thinking of no-prep veneers is that the patient has a rare blood problem, and his physician does not want any bleeding at this time. Both #8 and #9 are extremely thin and worn, and the patient wants a nice improvement.

Thanks always for your help.

– Anthony Badalamenti, DDS
New York, N.Y.

Dear Anthony,

I have placed no-prep veneers on top of old composites many times, especially if the shade is not radically darker than the tooth structure around it. Prior to placing the veneers, I pumice the teeth and the composites to make sure I have a clean surface for the phosphoric acid. Then I etch the composites while I etch the enamel, and for the same amount of time (15 seconds). Finally, I rinse the etching and place adhesive on the enamel and composite, etc. So if there is no recurrent decay around the composites, and they are not too low in value, there’s no need to replace them.

– Mike