Incidental Findings in Temporomandibular Joint Region Detected by Cone-beam Computed Tomography: A Retrospective Study

The purpose of this study was to investigate the prevalence of Incidental Findings (IFs) in the temporomandibular joint (TMJ) region detected in Cone-Beam Computed Tomography (CBCT) scans of maxilla and mandible.

In this study, 384 CBCT scans were reviewed for IFs of the TMJ region. Demographic data including age and sex were recorded. The scans were evaluated in multiplanar views: corrected sagittal, corrected coronal and axial sections. IFs in TMJ region were categorized into eight groups: osteoarthritis, flattening and erosion of condyle and articular eminence, osteophytes, subchondral pseudocyst, condyle hyperplasia, condyle hypoplasia, bifid condyle, and soft tissue calcification. Statistical analyses were performed using the SPSS statistic v.22.

From the CBCT scans, a total of 81 (21.1%) IFs were identified. 184 of the subjects (47.9%) were male and 200 (52.1%) were females. Their age ranged from 10 to 75 years old with a mean of 36.8 and a standard deviation of 13.9 years. The most frequent IFs were flattening and erosion of condyle and articular eminence (40.74%), followed by soft tissue calcification (30.86%). Osteoarthritis was not observed in any of the subjects. There was no significant difference between females and males in IFs of TMJ joint and its related structures. Flattening and erosion of condyle and articular eminence, soft tissue calcification, osteophytes and, subchondral pseudo cyst showed significant differences between individuals of different age ranges.

While examining CBCT images, it is critical to check for evidence of IFs in the TMJ region. The findings of this study emphasize the value of a thorough examination of all areas visualized on CBCT scans even those beyond the region of interest.