June 2009, Volume 5, Issue 6
Published by AEGIS Communications
Indications and Caveats for No-Prep Veneers
According to John R. Calamia, DMD, there certainly is a place for the use of minimal prep and no-prep veneers in dentistry. What clinicians need to realize, and be willing to inform their patients about, is that this place is a very small part of what veneers can provide patients, he says.
Successful Spots for No-Prep Veneers
Most of the no-prep cases that Calamia has seen in publications are diastema closures involving space between teeth, which require little or no color change in those areas. For those types of cases, dentists probably could use a no-prep or minimal-prep veneer, he says. For that matter, some of the current composite resins, which for the most part would be just added to the surface of the patient’s tooth, could also be used, Calamia suggests.
“In terms of its viability as a technique, I have utilized no preparation veneers, but it’s very important that I have the right case type in which to place them,” explains Michael R. Sesemann, DDS. “Usually it is a lingually verted tooth with perhaps a collapsed posterior segment where you’re trying to fill out a buccal corridor and make a person’s smile a little wider, or part of the dentition that can be treated with a purely additive technique.”
“The concept of no preparation at all on the tooth really only works if a tooth is minimal in its dimension, such as with a peg lateral,” believes Mark J. Friedman, DDS. “Here you can create a porcelain veneer that has the proper natural anatomy and confluence with the soft tissues without over-contouring.”
However, Raymond Bertolotti, DDS, PhD, cautions that no-prep veneers for peg-shaped laterals and lingually tipped teeth can be challenging for dentists and laboratories when they involve ultrathin stacked veneers. These are the exception, not the rule, he says.
According to Michael DiTolla, DDS, using no-prep veneers comes down to matching the suitability of a proposed dental treatment with what the patient is interested in; but that said, no-prep veneers are not a cure-all.
“No-prep veneers may work well with other restorative dentistry being performed in the same case in order to offer patients the opportunity to finish their smile at the same time,” suggests DiTolla. “For example, if an anterior bridge or anterior crown is replaced, no-prep veneers could be judiciously placed adjacent to these restorations so that everything blends, creating an easy way for a patient to finish off their smile.”
Practicing clinicians and academics alike welcome a more conservative approach to esthetically treating patients, and all agree that preservation of enamel is key. However, they do have concerns related to the no-prep version of veneers.
Not Irreversible. Friedman advises dentists to make an accurate diagnosis, restore teeth when they need restoration, and consider more conservative treatments when appropriate (eg, whitening, microabrasion, orthodontics) and not think that veneers are completely innocuous. Even a no-prep veneer is going to require tooth preparation to remove it, he says. When the veneer is removed, the resulting tooth preparation may, in fact, leave the tooth always needing a restoration due to the lost tooth structure.
“A no-prep veneer, in my opinion, is not an innocuous and reversible procedure,” believes Friedman.
Beware of Over-Contouring. Harald O. Heymann, DDS, MEd, warns that if a patient presents with otherwise normally shaped and sized teeth, there may be no way to avoid over-contouring the teeth without compensating reduction through some tooth preparation. He says that with no-prep veneers, there is no way to compensate for the additional thickness of the veneering material, so if the tooth is already of normal contour and size, then some degree of over-contouring will result, Heymann elaborates.
Gingival Response. As a consequence of over-contouring, one of Bertolotti’s concerns with no-prep veneers involves the gingival response. “If the teeth are tipped lingually, dentists can achieve a nice margin and everything will be fine,” Bertolotti says. “When a tooth is in the normal position and ceramic is added to it, there is potential for some gingival troubles from over-contouring and improper finishing.”
Fragile/Delicate in Nature. Heymann says that if the veneers are actually made as thin as some manufacturers claim, which is as thin as 0.3 mm, they would be very difficult to handle and fracture would be a real possibility. “Even if dentists could successfully seat these veneers, polymerization shrinkage alone could potentially crack a veneer that’s only 0.3 mm in thickness,” Heymann explains. “The fragility of these veneers during try-in and cementation is certainly a source of concern because of problems with potential fracture.”
Less than Desirable Color/Esthetics. Bertolotti’s other concern with no-prep or minimal prep veneers is that with something so thin, a great deal of opacity is needed in order for the veneer to change the color of the tooth. “The vast majority of no-prep ‘color correction’ veneer cases that I’ve seen look very flat and artificial since they don’t have any depth of color,” Bertolotti says.
Interproximal Finishing. Heymann is also concerned with the inability to access the margins of no-prep veneers interproximally to facil-itate proper finishing. When the margins are accessible, they can be smoothed and polished so that they are confluent with the contours of the tooth, he explains. “If you attempt to smooth the interproximal areas with just a diamond strip, you may inadvertently lighten or open the proximal contacts. The result is that the patient will end up catching all kinds of foods between their teeth, which obviously is not good from a periodontal standpoint,” Heymann says.