Traditional prosthesis, need grinding intact adjacent teeth addition to its own organization, porcelain bridges because they do not close, and prone to periodontal disease, because there is no root edentulous appear disuse atrophy, leading to the adjacent teeth loose in advance.
Dental implants and natural tooth structure as it is 3-4 times masticatory function of natural teeth, permanent restorations, so it is also known as the third deputy human teeth.