The evolution of dental implants 175

Fig. 5-79. Another type of Berman meshwork implant held in place by transosseous wires (arrows) in the molar and incisor areas. (From Berman, N.: Implant technique for full lower denture, Washington Dent. J. 19:15-17, 1950.)

Another American, Nicholas Berman of Seattle, Washington, altered Goldberg and Gershkoff's early technique. Recognizing that the bone must be ex-posed to truly evaluate its landscape, Berman made a stone model from an impression taken directly over the exposed bone. From this he cast a Vitallium meshwork that followed the exact configuration of the jaw (Fig. 5-77). Two or three weeks after the initial impression, he again revealed the site and fitted the meshwork under the periosteum and over the bone (Fig. 5-78). Four or five weeks after the implant had been seated and the periosteum had grown through the perforations and adhered the implant to the bone, the prosthesis was applied.

To prevent dislodgment of his implants, Berman tried two techniques: transosseous and circumferential wiring. For transosseous wiring he drilled holes in both molar areas and in the incisor area, passed tantalum wire through the holes, and then tied the wire over the implant (Fig. 5-79). He discarded this transosseous wiring technique in favor of circumferential wiring (Fig. 5-80). With this technique he encircled the entire mandible behind the mental foramina with tantalum wire (Fig. 5-81) .

Berman reported several successful cases. How-ever, again in light of recent knowledge, his implant designs and procedure may be criticized (Fig. 5-82).

Fig. 5-80. A Berman subperiosteal framework held in place by circumferential wiring. (From Berman, N.: Implant technique for full lower denture, Washington Dent. J. 19: 15-17, 1950.)

If his design had incorporated a means of holding the implant to the bone without wiring the mandible, the procedure would have been simpler. Berman's early recognition, however, that the implant must be made from models cast directly on the bone and that a great deal of alveolar bone resorption should have taken place before a subperiosteal intervention is much to his credit.