Inlays / Onlays

When more than half of a tooth’s biting surface is damaged or decayed, a dentist will often use a dental inlay or onlay to restore the tooth.

What are inlays and onlays?

Similar to a filling but designed to strengthen a tooth, inlays and onlays can be made of porcelain, gold or composite resin. The chosen material is bonded to the damaged area of the tooth. An inlay is typically adhered inside the cusp tips of the tooth, while an onlay is used for more substantial reconstructions. The onlay is designed to extend beyond one or more of the cusps of the tooth.

Traditionally, gold has been the substance of choice for inlays and onlays as it is strong and durable. However, porcelain has become increasingly popular as it is also strong and additionally offers color options to potentially match the natural shade of your teeth.

How are they applied?

Inlays and onlays are often placed over two visits. During the first appointment, the damaged or decaying portion of the tooth is removed and the remainder of the tooth is prepared for the inlay or onlay. To ensure proper fit and an aligned bite, an impression of the tooth is made and sent to a lab for fabrication. Our doctors will then apply a temporary sealant to protect the tooth until the next visit.

At the second appointment, the temporary sealant is removed. Our doctors will check the inlay or onlay for correct fit. If the fit is ideal, the inlay or onlay is then bonded to the tooth with a strong resin and polished to a smooth finish.


Traditional fillings can diminish a natural tooth’s strength by as much as 50%. Conversely, inlays and onlays, which are bonded directly onto the tooth, can actually increase the strength of a tooth by up to 75%. As a result, they will often last between 10 and 30 years. When the damage to the tooth is not extensive enough to warrant the application of a crown, inlays and onlays may offer a good alternative.