Morphometric variations of human mandible in Indian population: comparison between subjects having healthy and ankylosed temporomandibular joint

The temporomandibular joint (TMJ) helps to perform the functional activities of the oral cavity. Such activities often get affected by end-stage degenerative disorders such as TMJ ankylosis. Alloplastic reconstruction using TMJ implants helps to restore those activities. However, commercially available stock implants often suffer from fit discrepancies in Indian population. Therefore, this study is aimed to compare comparison between mandibular morphometry of subjects with healthy or normal TMJ joints (TMJN) and patients with TMJ ankylosis (TMJA) from the Indian population. Furthermore, the observed mandibular morphometry has also been compared with those of the other populations. In this study, the most useful anatomical parameters of mandible are measured from the CT-based reconstructed mandibles of 367 Indian subjects (199 healthy;168 ankylosis). Significant differences in ramus length (healthy males: 61.74{+/-}7.53 mm, ankylosis males: 46.81{+/-}10.35 mm; healthy females: 55.21{+/-}6.12 mm, ankylosis females: 41.77{+/-}8.57 mm) and condyle width (healthy males: 18.76{+/-}3.22 mm, ankylosis males: 22.67{+/-}5.56 mm; healthy females: 16.94{+/-}2.41 mm, ankylosis females: 21.31{+/-}4.65 mm) have been observed between mandibles of ankylosis and healthy subjects. Differences in ramus length (affected side: 43.87{+/-}9.51 mm; unaffected side: 55.34{+/-}7.12 mm) and condyle width (affected side: 23{+/-}4.68 mm; unaffected side: 17.99{+/-}2.81 mm) were also observed between affected and unaffected sides of mandibles for unilateral ankylosis patients. Ramus length in healthy subjects was found to be the most statistically significant parameter between mandibles of Indians and other populations.