An inlay or onlay is used when the cavity is too big for a conventional filling, but isn't so big that a crown is required. An inlay is a filling within the cusp tips of the tooth. Onlays (also known as overlays) will overlay one or more cusps in order to protect and strengthen the tooth. Inlays and onlays can be fabricated out of ceramic tooth colored materials or out of a cast gold alloy. Whereas ceramic restorations lack are more cosmetic, gold restorations are one of the strongest and longest lasting restorations in dentistry.

White Porcelain Inlay	Gold Inlay