CBCT-based posterior maxillary morphometry of the maxillary tuberosity and cortical bone thickness in the third-molar region

Abstract

Fractures involving the maxillary tuberosity and buccal cortical bone represent notable complications during maxillary third-molar extraction and may be influenced by anatomical characteristics of the posterior maxilla. This study aimed to evaluate maxillary tuberosity dimensions, buccal and palatal cortical bone thickness, and their associations with the anatomical characteristics of erupted maxillary third molars using CBCT. This retrospective study analyzed CBCT scans of adults aged ≥ 25 years presenting with fully erupted maxillary third molars. Maxillary tuberosity width, height, and length were measured at standardized intervals, and buccal and palatal cortical bone thickness were recorded at predefined reference levels. Mesiodistal crown width, root number, and root length were also assessed. Statistical analyses included Mann-Whitney U, Kruskal-Wallis, and Spearman’s rank correlation tests. A total of 120 patients (57.5% female; mean age 35.06 ± 7.13 years) were included. Cortical bone thickness measurements demonstrated minor side-related differences, with palatal cortical bone thickness exceeding buccal thickness on the right side and comparable values observed on the left side. Buccal cortical bone thickness differed significantly across age groups on the right side ( p = 0.012). Tuberosity dimensions did not differ significantly according to sex or side. Root morphology showed no significant association with cortical bone thickness or tuberosity measurements. Tuberosity height displayed weak positive correlations with certain root-length parameters, while buccal cortical bone thickness showed limited associations with tuberosity dimensions. The posterior maxilla demonstrates consistent morphometric patterns around erupted third molars, including a relatively thinner buccal cortex and stable tuberosity dimensions. These findings provide CBCT-based anatomical reference data regarding posterior maxillary morphology.

The authors' abstract, as published at the source. BMC Oral Health, 2026 · DOI ↗