Location and patency of the ostium for sinus augmentation from an implant treatment planning perspective: A retrospective CBCT study

Abstract

<h3>Background</h3> In the posterior maxilla, pneumatization of the maxillary sinus paralleled with resorption of the residual ridge markedly reduces bone volume. Sinus lift/sinus augmentation is usually performed to increase bone volume at these sites. The total height needed for augmentation depends on residual ridge height. The ostium, which is an anatomical conduit that opens into the middle meatus, must be patent; blockage due to inflammation or infection can lead to confinement of infection within the maxillary sinus. Clinicians should be cautious while planning sinus augmentation procedures in patients with radiographically evident sinus disease. <h3>Objective</h3> The objective of this study was to evaluate the location of the ostium with reference to the sinus floor and/or mucosal thickening when present. <h3>Study Design</h3> In total, 200 sino-nasal complexes comprising 100 dentate and 100 edentulous scans were retrospectively assessed using CBCT. The coronal section demonstrating the ostiomeatal complex was selected as a reference view to perform measurements of the sinus. The measurements were made by 2 evaluators. Comparative analyses of measurements were performed between dentate and edentulous patients. <h3>Results</h3> The safe height to which the sinus can be elevated without compromising the integrity of the ostiomeatal complex was calculated for each sinus. In the presence of significant mucosal thickening, the height available was calculated by subtracting the height of mucosal thickening from the sinus floor to the location of the ostium. The available height was approximately 27.05 mm for dentate and 23.40 mm for edentulous patients. The interoperator reliability was excellent for all parameters evaluated. <h3>Conclusion</h3> This retrospective study shows that CBCT is valuable in evaluating the location and patency of the ostium for planning sinus augmentation procedures for dental implant placement. <b>Statement of Ethical Review</b> Ethical Review or exemption was not warranted for this study