Prevalence of anatomic variations of temporomandibular joint on orthopantomogram and cone-beam computed tomography: A retrospective study

Maxillofacial radiography by means of orthopantamogram is used as a routine screening tool in the diagnosis and treatment planning in various fields of dentistry and is found to be less expensive when compared to other advanced imaging modalities like computed tomography, magnetic resonance imaging and cone-beam computed tomography. Morphological variations in the shape of mandibular condyle, coronoid process and sigmoid notch have been documented in the literature as indispensable aids in anthropological and forensic studies. 100 OPG and CBCT scans of same participants, comprising of 200 temporo-mandibular joints were evaluated for anatomical variations in shapes of mandibular condyle, coronoid process and sigmoid notch. The prevalence of various morphological variations were correlated with age and gender and subjected to statistical analysis. The most common shape of condyle, coronoid process and sigmoid notch on OPG was round, whereas on CBCT the most common shape of condyle, coronoid process and sigmoid notch were flat, triangular and wide respectively. Variations in the morphology of shape of mandibular condyle, coronoid process and sigmoid notch using panoramic radiographs can be tentatively used as a screening tool in human identification, owing to its ready availability and low cost.