Correlation between planned prosthetic and residual bone trajectories in dental implants

Statement of problem. The success of dental implant treatment relies on a well-developed treatment plan approach. Historically, implant placement was guided mainly by residual bone height and width, at times compromising prosthetic needs. Purpose. This study analyzed the amount of deviation between planned prosthetic trajectory and residual bone trajectory in different areas of the maxillary and mandibular dental arches, by using a tomographic survey in conjunction with imaging/surgical guides. Methods and material. Ninety-two patients with a total of 235 implant sites were selected for the study. An imaging and surgical guide with a radiopaque indicator was constructed to determine the planned prosthetic trajectory. Cross-sectional tomograms were taken through the indicator at each implant site. The outlines of the available bone, planned prosthetic trajectory, and residual bone trajectory were traced, and the difference in the trajectory between the 2 trajectories was determined. Results. Discrepancies between the planned prosthetic and the residual bone trajectories were greater in the mandibular molar area. This site was statistically different from other site groups at P=.05 (Tukey method). Statistically, all other site groups were not significantly different.