Assessment of the Association Between Tooth Loss Patterns and CBCT-Derived Gray Values of the Mandibular Condyle: A Retrospective Study

Background/Objectives: This study aimed to evaluate the relationship between tooth loss and mandibular condylar cone-beam computed tomography (CBCT)-derived gray values according to different patterns of edentulism. Methods: This retrospective study was conducted using the CBCT archive of the Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Harran University. All CBCT examinations were obtained using a single CBCT scanner and a standardized acquisition protocol. Demographic variables such as age and gender, along with edentulism status based on the Kennedy classification, were recorded to assess their relationship with mandibular condylar CBCT-derived gray values. The collected data were statistically analyzed using the independent t-test, Pearson’s chi-square test, one-way ANOVA with Bonferroni-adjusted post hoc comparisons, paired samples t-test, and multivariable linear regression analysis. Results: A total of 371 CBCT scans (144 males and 227 females) were included. The mean age was 41.67 years for females and 41.87 years for males. The mean CBCT-derived gray values of the right and left mandibular condyles were lower in males (right: 577.08 ± 161.18; left: 353.89 ± 181.41) compared to females (right: 702.02 ± 137.59; left: 460.47 ± 163.65) (p < 0.001 for both sides). In a secondary analysis, the mean CBCT-derived gray value of the right condyle (653.53 ± 159.13) was higher than that of the left condyle (419.10 ± 178.27) (unadjusted p < 0.001). A nominal overall association between maxillary dentition status and right condylar CBCT-derived gray values was observed after adjustment for age, sex, and mandibular dentition status (p = 0.024). However, this association was not corrected for multiple testing across study outcomes and should therefore be interpreted as exploratory. No significant overall adjusted associations were observed for mandibular dentition status or for left condylar gray values. Conclusions: Descriptively lower CBCT-derived gray values were observed in completely edentulous individuals; however, these differences were not statistically confirmed and were not consistent across all dentition classifications. These findings should also be interpreted cautiously, as CBCT-derived gray values are scanner- and protocol-dependent and do not represent absolute Hounsfield units or direct measurements of bone mineral density. Further longitudinal and calibrated imaging studies are needed to clarify the relationship between tooth loss and mandibular condylar bone changes.