If you're like most adults, you probably have at least 2 or 3 silver (amalgam) fillings in your teeth. These mercury filled menaces makes natural teeth look dark, and are rarely removed without the discovery of additional cavities underneath. In past years, patients had two basic choices for restoring large dacay on teeth: larger silver fillings or crowns. Similar to crowns, inlays and onlays are custom made from impressions of your prepared tooth. The big difference is less tooth structure is removed. The finished restoration is not only life-like in appearence but also strong and wear resistant.