Tooth roots are usually replaced with dental implants. It is also placed in the jawbone as a tooth root and is not visible after surgical placement. Dental implants are used to attach dentures, bridges and crowns in a variety of ways. They are usually made of titanium which is strong, lightweight and biocompatible. Titanium and titanium alloys are metals that are commonly used in some bone implants such as orthopedic implants and joint replacements.