Dental inlays and onlays are a more conservative approach to tooth restoration than full crowns. The are used to repair rear teeth that have mild to moderate tooth decay, or for cracked teeth where the damage does not warrant a dental crown. Porcelain, composite resin and sometimes gold is used to create inlays and onlays. Inlays refer to those procedures where the bonded material is limited to the center of the tooth, while onlays refer to those procedures where the bonded material can extend further to one or more cusps of the tooth.
Typically, two visits are required for the placements of inlays and onlays. In the first visit, your dentist will take an impression of your tooth, which will be sent to a lab to create the permanent inlay or onlay. Before you leave, he will fit your tooth with a temporary inlay / onlay to keep the tooth protected between visits. During your second visit, the dentist will remove the temporary protective material and fit your tooth with the permanent inlay or onlay received from the lab.