Pneumatic spaces represent sites of minimal resistance, facilitating the spread of various pathological processes into the joint such as tumors, infection or fractures or vice versa. Considering the clinical importance of temporomandibular joint, prevalence of pneumatic spaces of the temporal bone in relation to TMJ in the roof of the TMJ fossa; articular eminence; zygomatic process and peritubal area was determined using Computed tomography. Laterality and gender wise prevalence of pneumatic spaces around the TMJ was also assessed.

A total of 100 high-resolution CT images of adult patients subjected to CT scan for the base of skull/temporal bone were utilized. Axial, reformatted coronal and sagittal images were analyzed on a DICOM viewer for the presence and distribution of pneumatic spaces of the temporal bone around TMJ in the roof of TMJ fossa, articular eminence, zygomatic process and peritubal area.

The extent of pneumatization of the temporal bone varied considerably. The prevalence of pneumatization of the roof of the TMJ fossa was 52%, articular eminence (12%), the root of the zygomatic process (5%) and peritubal area was 56%. Higher frequency of bilateral pneumatization was seen. No statistically significant correlation was seen in gender wise distribution of pneumatization.

The present study revealed higher prevalence of pneumatization of temporal bone around TMJ. The knowledge of these air spaces is helpful for the interpretation of imaging studies and to understand the spread of pathological processes into the joint.