Optimizing pterygoid implant placement without sinus intrusion in edentulous vietnamese patients: A comprehensive tomographic analysis and cross-sectional study.

Background: Severe maxillary resorption presents challenges in dental implant placement. This research aims to assess the feasibility, angular orientation, and appropriate length of pterygoid implants in patients with significant maxillary atrophy. Material and Methods: The study examined Cone Beam Computed Tomography (CBCT) scans from 60 completely edentulous patients classified as Cawood and Howell's Classes V or VI, with less than 4mm residual bone height in their posterior maxilla. Experienced oral and maxillofacial surgeons and researchers conducted virtual pterygoid implant placement, evaluating various implant positions. Results: Position C was the most frequent, comprising 34.6% of cases evaluated. The average antero-posterior angle across all positions was 51.82±5.57 degrees, and the bucco-lingual angle was 74.15±16.53 degrees relative to the Frankfort horizontal plane. The optimal location for implant neck placement was approximately 10 mm from the most distal point of maxillary tuberosity, angled 50 degrees antero-posteriorly and 75 degrees bucco-lingually. While 18 mm implants were typically used, lengths of 20-22 mm were sometimes necessary for bicortical anchorage. Conclusions: This study demonstrates the viability of pterygoid implants even in cases of significant maxillary atrophy. The findings emphasize the importance of adapting implant placement strategies to individual patient anatomies. Further research may be needed to refine techniques for patients with severe maxillary resorption.