Composite resin fillings are the most common alternative to dental amalgam. They are sometimes called “tooth-colored” or “white” fillings because of their color. Composite resin fillings are made of a type of plastic (an acrylic resin) reinforced with powdered glass filler. This material is considered safe. This plastic and glass mixture contains no metal and can be shaped to resemble a real tooth. It is usually hard to tell that a tooth has even been filled!