Inlay/Onlay
To repair damage involving over ½ of the tooth's biting surface, rather than using a simple filling, or a crown, a dentist will often use an inlay, or an onlay.
Inlays and onlays, can be porcelain, gold, or composite resin and are bonded to the damaged area of a tooth. An inlay is similar to a filling and lies inside the tooth; an onlay is larger and sits on top of parts of a tooth.
Inlays and onlays may require two visits. At the first visit, the old filling, or decay, is removed, and the tooth is prepared for the inlay / onlay. An impression of the tooth is made and sent to a dental laboratory. This impression will be used to construct, a porcelain, or gold inlay / onlay that will fit exactly into your tooth. At this time the dentist will place a temporary sealant on your tooth and schedule a second appointment.
At the second visit, the temporary sealant is removed. Your dentist will then ensure that the inlay / onlay fits properly in your tooth and matches your bite. Once correctly fit, the inlay / onlay is bonded into the tooth with a strong bonding resin, and polished smooth.
Alternatively, a ceramic inlay or onlay can be made using the CEREC method. This requires only one visit.
Considerations
Typically fillings can reduce the strength of the tooth by up to 50%. Inlays and onlays, however, because they are bonded directly into the tooth with special resins, can actually increase the strength of the tooth by up to 75%; as a result, they can last from 10-30 years, and in some cases, provide a good alternative to a crown. |
