A FRESH VENEER FOR DAMAGED TEETH
The most smile-altering procedure Nora Davison underwent may have been the veneers on her eight front top teeth.
Veneers—fabrications of tooth-colored materials such as porcelain—cover unsightly or damaged teeth.
Davison’s teeth had been worn down by years of grinding. “They were little squares,” she says. Front teeth are supposed to be rectangular and longer than they are wide. Veneers, the last step in Davison’s treatment, restored this look.
Davison’s veneers were crafted in a lab, based on molds of her teeth made by Watkins. But veneers can also be milled chair-side using technology known as CAD/CAM (computer-aided design/computer-aided manufacturing). Such devices are linked via software to a milling machine that’s able to generate, from a tiny block of strength-enhanced porcelain, veneers, crowns, and tooth-colored fillings. The process marries digital photos taken by an oral camera with computer software capable of designing restorations, and it produces near instantaneous results.
“Seven minutes,” says Stuart Ross, who uses CAD/CAM technology at his office in downtown DC. “The patient can sit there with a mirror and say, ‘I like that’ or ‘It’s too long.’ If they don’t like it, you can craft another.” An advantage is that veneers can be completed in a single office visit instead of two.
No matter the production method, before anything is permanently attached to a tooth, the porcelain must be matched to the shade of the patient’s enamel.
“Probably the hardest thing in dentistry is to do a crown or veneer on a single front tooth,” says Gray. “On the last visit, I’m going to want the patient here for an entire afternoon. I’m going to put them in various types of light—outside, in natural light, in a dark hallway, in fluorescent light. I need to make sure the veneer shade looks natural.”
Gray says a natural look can be attained through “characterization,” a process in which veneers are designed not only to incorporate different hues and levels of translucency—which real teeth exhibit—but to accommodate nicks or other small flaws.
Gray, Watkins, and other dentists who rely on labs provide patients with “temporary veneers” for a week or two until the permanent ones are crafted. These are plastic versions that are attached with a temporary adhesive. Patients can get a sense of how the new teeth feel and look and whether changes need to be made.
Veneers are subject to wear much as actual teeth are, and they have to be brushed and flossed. Their lifespan varies, but most last 15 years or more.
Davison can continue using home whitening—though veneers will neither lighten nor stain, Watkins says. He has advised Davison to wear a night guard to keep her from grinding her new dental work. Although porcelains used today are stronger than earlier versions, veneers, like actual teeth, can be damaged.
Some dentists advertise veneers as a substitute for braces. The contention is that by bonding a veneer onto a crooked tooth, the incongruity can be concealed. But a number of professionals find fault with this approach.
“Yes, instant orthodontics can happen with veneers,” says Watkins, “but patients need to understand the downside. Crooked teeth can require cutting down more of the natural tooth to attach the veneer. It’s going to require bonding the veneer onto the inner part of the tooth, called the dentin. The dentin is not nearly as reliable for bonding onto as the enamel,” or the outer part of a tooth. The more tooth structure a dentist has to cut away, the greater the risk of nerve problems and root damage.
Getting veneers is an irreversible procedure. Once a tooth is reduced to prepare it for the veneer, it can’t be restored.
Dentists debate how much preparation is required prior to attaching veneers, even when crooked teeth aren’t involved. Some veneers are advertised as being so thin that no preparation is required and no anesthetic is necessary. Many dentists argue that some tooth surface must be shaved off for a veneer to fit properly. Otherwise, they say, the veneer—no matter how thin—will jut beyond the surrounding teeth, forming a ledge at the gum line. Think of a press-on fingernail and the ridge that forms where it meets the cuticle.
Says Rockville dentist Patrick Murray: “The advantage of prepless veneers is that you don’t have to prep the teeth; the disadvantage of prepless veneers is that you don’t have to prep the teeth. If you have bulky margins or ledges, the gums will go nuts. They’ll either pull back away from the teeth or it will be a food trap, leading to decay.">> Next: How to Fix a Misshapen Tooth and Bonding