Inlays and Onlays
An inlay or onlay is similar to a dental crown in its purpose, which is to restore a damaged or infected tooth. However, inlays and onlays do not cover the entire crown of a tooth, but rather a part of it.
The difference between an inlay and an onlay is in the area that it covers. An inlay rests between the cusps on the chewing surface of a tooth. An onlay can extend over the cusps and the sides of the tooth to restore a larger area. Both inlays and onlays are typically made from dental porcelain or zirconia for the most cosmetically-pleasing results.