Inlays and onlays can be used to restore a tooth with extensive areas of decay or damage that would be difficult to repair with a normal filling. As they are more durable than fillings, they are usually placed on the chewing surfaces of the back teeth or can repair large areas on the front teeth. They also offer a less invasive alternative to the full coverage provided by crowns.
Inlays and onlays are made from hard-wearing materials such as porcelain or composite resin. If aesthetics are not an issue, gold is a hardwearing choice. Unlike fillings, they are produced outside the mouth in a dental laboratory and then fitted to the tooth by the dentist. An inlay is cemented within the cavity and an onlay covers more of the tooth and extends over the edges.