Introduction: The purpose of this study was to obtain insight into the perioperative condition of the maxillary sinus in the LeFort I osteotomy by evaluating clinically and radiographically. Materials and methods: 25 patients who required conventional LeFort I procedures for orthognathic correction were included in the study. Damage to the maxillary sinus during the procedure and its recovery were prospectively analysed using validated questionnaires for sino-nasal complaints using RSOM-31 (RSOM − rhinosinusitis outcome measure), VAS score (VAS − visual analogue scale) and CT scan to compare and analyse changes in maxillary sinus prior to surgery and postoperatively 2 months after the surgery. The scores obtained from RSOM-31 questionnaire was analysed using Chi-square test, VAS questionnaire was interpreted using Wilcoxon sign rank test and CT scan findings were analysed using Fischer's exact test. Results: Mucosal thickening assessed using CT scan was the only consistent finding that was evident for all the patients who underwent LeFort I osteotomy which showed a statistically significant results of P < 0.05, whereas clinical correlation showed insignificant results of P > 0.05. Conclusion: In our attempt on extensive patient analysis we found that mucosal thickening was the prime alteration that was observed radiographically and no clinical changes were evident.