The evolution of dental implants 177

A   B

Fig. 5-82. The fate of an implant set either over too much alveolar bone, or loose because of design flaws. A, Berman's circumferentially wired implant appears successful 3 months after implantation. B, Two years later the implant and wire are loose as a result of bone atrophy. (From Berman, N.: Implant technique for full lower denture, Washington Dent. J. 19:15-17, 1950.)

Fig. 5-83. The evolution of Lew's subperiosteal mandibular implant from 1948 (top left) to 1955 (bottom right). Gradually the amount of metal became reduced from a bulky mesh to strategically placed bars and struts with simple, tapered abutment posts. (From Lew, I.: Progress in implant dentistry—an evaluation, J.A.D.A. 59:478-492, 1959. Copyright American Dental Association. Reprinted by permission.)