A filling is often the first thing that comes to mind when you mention the dentist. A dental filling is simply the material that is placed in the tooth to repair damage from a cavity or fracture. There are several different materials that can be used to repair a tooth. The material chosen is based on the extent of the damage to the tooth as well as its visibility. While gold and porcelain are often the material of choice for larger restorations located on the back teeth, the majority of fillings placed are either composite (tooth-colored) or amalgam (silver).