In posterior quadrants when only a single tooth was missing, fig. 1, the author originally used the Linkow "vent-plants" with a considerable amount of success. To prevent the screw implant from loosening during the early catabolic stages of bone metabolism the crown was fabricated prior to implant insertion. The crown always included a deep mesial and distal occlusal rest or lingual clasps to help stabilize it. Figure 2 shows the prefabricated crown and vent-plant imploded with aluminum oxide. The crown was then fitted into position and ground into proper occlusion prior to the insertion of the implant, fig. 3, and radiographed, fig. 4. Figures 5, 6, 7 show the preparation of the socket with an entering type bur. Figures 8-11 show the drilling into the bone with various sized bone burs to widen it just slightly smaller in diameter than the vent-plant, fig. 12, which made its own threading into the bone as it was of a self-tapping type. Figures 13 and 14 show the vent-plant in its proper position in the bone and the final periapical film showing its actual depth. The crown was then immediately cemented over the implant for immediate stabilization, fig. 15.

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