Inlays & Onlays


Like crowns, inlays and onlays are custom-crafted porcelain restorations that can repair and strengthen your teeth, particularly after decay or structural damage. However, these restorations are a more conservative option than crowns, allowing your dentist to preserve more of your healthy tooth structure. Inlays and onlays are used to strengthen the chewing surfaces of your molars following treatment for trauma or decay. Inlays lie between the sharp cusps, while onlays extend over the cusps and down the sides of your tooth.

When more than half of the tooths biting surface is damaged a dentist will often use an inlay or onlay.

What are inlays and onlays?

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 has been the material of choice for inlays and onlays. 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.

How are inlays and onlays applied?

Inlays and onlays require only one appointment 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.

Dr. Caron or Dr. Kenney 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.

Considerations for inlays and onlays

Traditional fillings can reduce the strength of a natural tooth by up to 50 percent. As an alternative, inlays and onlays, which are bonded directly onto the tooth using special high-strength resins, can actually increase the strength of a tooth by up to 75 percent. As a result, they can last from 10 to 30 years. In some cases, where the damage to the tooth is not extensive enough to merit an entire crown, onlays can provide a very good alternative.