Anatomical Relationship Between Impacted Maxillary Third Molars and the Maxillary Sinus Floor: A Cone-Beam Computed Tomography–Based Study
Abstract
Background: Impacted maxillary third molars are often located in close proximity to the maxillary sinus, which may increase the risk of sinus perforation during surgical extraction. Conebeam computed tomography (CBCT) enables comprehensive 3-dimensional assessment of this anatomical relationship. The present study investigated the vertical and horizontal sinus–root relationships of impacted maxillary third molars using CBCT data obtained from individuals in Türkiye. Methods: This retrospective study evaluated CBCT images of patients aged 25 years and older with fully or partially impacted maxillary third molars. Vertical and horizontal sinus–root relationships were classified according to Kwak et al, while tooth angulation was determined based on Archer’s classification. Statistical analyses were conducted with the level of significance set at P < .05. Results: Data from 196 individuals were analyzed. Vertical angulation was the predominant impaction pattern on both sides. Type II represented the most frequently identified vertical sinus relationship, marked by direct contact between the sinus floor and the root apices. In the horizontal plane, the bilateral predominance of type 2 was noted, with the sinus floor situated between the buccal and palatal roots. No statistically significant differences were identified among age groups, sexes, or sides with respect to angulation or sinus relationships (P > .05). Conclusion: Impacted maxillary third molars most frequently exhibit vertical angulation accompanied by type II vertical and type 2 horizontal sinus–root relationships. These anatomical patterns appear consistent across demographic variables. Cone-beam computed tomography provides detailed 3-dimensional assessment of the anatomical relationship between impacted maxillary third molars and the maxillary sinus floor and may provide additional information relevant to preoperative assessment and surgical planning.