Assessment of osseous morphology of temporomandibular joint in asymptomatic participants with chewing-side preference.

Chewing-side preference (CSP) may be associated with temporomandibular disorders. However, little information exists regarding whether CSP will lead to osseous changes of temporomandibular joint (TMJ) in asymptomatic participants. The aim of this study was to investigate the relationship between osseous morphology of TMJ in asymptomatic participants with CSP and without CSP. Of the 121 healthy dentate participants, 35 participants with left CSP, 38 with right CSP and other 48 without CSP were scanned by cone-beam computed tomography. The dimensions of the reconstructed images of opposing TMJs were compared. Statistical analyses were performed using spss 16.0 software. The results showed that there were no significant differences between the dimensions of bilateral structures of the TMJ (P1 > 0·05) in participants without CSP. However, the posterior-superior, posterior and lateral joint space of the preferred side were smaller than that of the unpreferred side in participants with CSP (P2 < 0·01) and bilateral TMJ in participants without CSP (P3 < 0·01). In addition, width of condylar neck of the unpreferred side both in sagittal and perpendicular to the long axis of condyle views was greater than that of the preferred side in participants with CSP (P2 < 0·01) and bilateral TMJ of participants without CSP (P4 < 0·01). Also, the inclination of articular eminence of the preferred side in view perpendicular to the long axis of condyle was less than that of the unpreferred side (P2 < 0·05). These findings suggest CSP affects osseous morphology of TMJ in asymptomatic participants.