The subperiosteal metal implant, as with all new approaches of any importance, has its rabid followers, its more cautious enthusiasts, and finally a good number of severe critics who back up their argu ments with rather convincing histopatho logic studies on animals. The idea is not a revolutionary or a new one, as has been stated. There have been periods when interest in metal im plantation flared up and then just as suddenly died down. The inference is that becausc of an initial surgical success the interest mounted, and then lagged when implants failed (because of the inetals used or the technics followed). This rising and falling of interest can be noted best in the nineteenth century when many physicians, including the eminent surgeon, Joseph Lister,1 advocated the use of implanted metal in surgery. He embedded a silver wire to fix a fractured patella. A brief perusal of the illustration might give a better over-all picture of the in terest and activity in metal implantation since 1876. Up to the first decade shown in the illustration, the literature was crammed with articles on implantation, replantation and transplantation. The articles referred not only to human teeth, but also to animal teeth and bits of bone and cartilage of every size and descrip tion. In the last quarter of the nineteenth century, references are beginning to be made to metal implantation. Metallic implantations were made with capsules which were merely placed into sockets left by the extraction of teeth or into holes drilled into the mandible. If heal ing took place around these foreign bodies, individual artificial teeth were fitted or screwed into them. There must have been a modicum of success because in the second and third decades there was a flurry of activity. The metals used at that time were gold, silver and lead. By the fourth decade there were two influences beginning to be felt. First, it became obvious that metallic implanta tion began to fall off. There was a hint at this time, though, pointing to the causes of failure. Casto2 in 1914 implanted three iridioplatinum roots. The important inference is that scientists at this time were thinking that perhaps the more inert metals held the secret to tolerance of metal by bone. This eventually proved to be so. From 1920 to 1940 the implantation of metals suffered a severe setback, however. The professions began to blame almost every thing on the dental focus of infection, and the interest in metal implantation in dentistry dropped down to nearly zero.