Inlays and onlays are used to correct smaller cavities or replace mercury (amalgam) fillings. Old-fashioned mercury fillings cause cracking and discoloration of teeth over time. Inlays and onlays, made from tooth-colored porcelain or composite resin, are virtually undetectable in the mouth.
Inlays and onlays also conserve more of your natural tooth structure, and when bonded in place, can strengthen the teeth by up to 75 percent. Perhaps best of all, they can protect teeth from further damage and the need for more extensive restorations.