When more than half of the tooth’s biting surface
is damaged, a dentist will often use an inlay or onlay. Inlays and onlays can
be made of porcelain, gold, or composite resin. These pieces are bonded to the
damaged area of the tooth. An inlay, which is similar to a filling, is used
inside the cusp tips of the tooth. An onlay is a more substantial
reconstruction, similar to the inlay but extending out over one or more of the
cusps of the tooth.
Traditionally, gold was used though in recent
years, however, porcelain has become increasingly popular due to its strength
and color, which can potentially match the natural color of your teeth.
Inlays and onlays require two appointments to
complete the procedure. During the first visit, the filling being replaced or
the damaged or decaying area of the tooth is removed, and the tooth is prepared
for the inlay or onlay. To ensure proper fit and bite, an impression of the
tooth is made by the dentist, and sent to a lab for fabrication. The dentist
will then apply a temporary sealant on the tooth and schedule the next
appointment.
At the second appointment, the temporary sealant
is removed. Your dentist will then make sure that the inlay or onlay fits
correctly. If the fit is satisfactory, the inlay or onlay will be bonded to the
tooth with a strong resin and polished to a smooth finish. Inlays or onlays can
last from 10 to 30 years.