Inlays and onlays are types of restorations that are used when the damage to the tooth requires more than a filling but doesn’t necessarily require a crown. They can be used to replace a larger filling that is failing, such as metal amalgam, or to restore a damaged tooth.

Inlays are used to fill in the space between a tooth’s cusps (outer ridges of the tooth), and typically require minimal reduction of the tooth structure.

Onlays are placed over the cusps, though not as extensively as a crown.The fact that both onlays and inlays require very little reduction of tooth structure means they are a conservative solution and have the benefit of preserving the strength of a natural tooth, making them a great alternative to crowns.