Endosteal Implants are devices that are placed into bone. Endosteal implants may be used when there is enough bony structure to support the intended reconstruction. There are several basic designs. A screw implant is commonly used where there is adequate bone strong enough to support the tooth. Sometimes a screw implant requires bone grafting to create enough bone. A plate implant is used when the bone is too thin to support a screw implant without grafting. A ramus frame implant is a special device which uses plate forms connected by a prefabricated bar to supply a support for a full lower denture. Endosteal implants are pre-manufactured in one, two, or three piece systems. One piece systems are the strongest. Two piece systems can be very strong and should have hermetically sealing parts. Many three piece systems are fraught with complications which Dr. Martin believes make them a poor choice in restorative dentistry. Endosteal implants may not be an appropriate system when the structures of the mouth and face are too deteriorated or damaged to allow for drilling into the bone. The one and two piece systems have had FDA approval since the 1960s and before. The American Dental Association approved a three piece system in 1984.