An Anatomic Study on the Maxillary Sinus Mucosal Thickness and the Distance between the Maxillary Sinus Ostium and Sinus Floor for the Maxillary Sinus Augmentation

Background and objectives: The average rate of chronic sinusitis after maxillary implantation was approximately 5.1%. However, the evidence of predictive risk factors for sinusitis after implantation is lacking. The aim of this study was to perform an anatomic study on the maxillary sinus mucosal thickness (MSMT), the distance between the maxillary sinus ostium and sinus floor (MOD), and the MSMT/MOD ratio as a preoperative risk indicator for sinusitis after maxillary dental implantation. Materials and Methods: Between October 2008 and October 2019, all patients referred to the otolaryngology department were included in this study. A total of 120 patients were enrolled. The 95 patients who received no treatment prior to implantation were classified into Group A, the 16 patients who used antibiotics before implantation were classified into Group B, and the patients who had implants inserted after functional endoscopic sinus surgery were classified into Group C. The MSMT, MOD, MSMT/MOD ratio, anatomical factors associated with ostial obstruction, and the occurrence of postoperative sinusitis were reviewed. Results: There were significant group differences in MSMT (Group A vs. Group B, p = 0.001; Group B vs. Group C, p = 0.003; Group C vs. Group A, p < 0.0001). The MOD showed no significant difference among the three groups. The MSMT/MOD ratio showed significant differences between Groups A and B (p = 0.001), B and C (p < 0.0001), and C and A (p < 0.0001). Conclusions: It is important to check not only the proportion of the maxillary sinus occupying lesion, but also the status of the maxillary sinus osteomeatal complex when making therapeutic decisions. In addition, collaboration between dentists and otolaryngologists could improve outcomes in patients with maxillary sinus lesions.