A dental implant is a prosthetic replacement for a missing tooth. Natural teeth consist of the crown and the root. The crown is the visible section that is covered with white enamel. Supporting the crown is the tooth root which extends into the jawbone. The root is the part of the tooth that is effectively replaced by an implant.
There are commonly three parts to what is described as an implant - the implant device itself (which is inserted directly into the bone); the abutment - the piece that connects the implant device to the third part - the overlying crown or denture.
Today's implants are predominantly made of titanium, a metal that is bio-compatible and offers strength and durability as well as a unique property of fusing directly to bone - the process known as osseointegration. Other materials, such as zirconium, might be used to make implants in the future. But for now, these materials have not been perfected for general use.