Relationships between geometry and kinematic characteristics in the temporomandibular joint

Abstract

Motions of the temporomandibular joint (TMJ) involve both translation and rotation; however, there may be substantial variations from one human to another, and these variations present significant difficulties when designing TMJ prostheses. The disc–condyle glides along the temporal bone and the condyle centre describe a curve that depends on the individual morphology.

This study analyses disc–condyle rotatory and translatory displacements moving all along the temporal bone facets which are mainly composed of two areas: the articular tubercle slope (ATS) and the preglenoid plane separated by the articular tubercle crest. Displacements were quantified using 3D video analysis, and this technique was computer-assisted.

From a population of 32 volunteers, we were able to establish a correlation between the kinematic characteristics of the joint and the disc–condyle trajectories. This study quantifies the geometrical characteristics of the ATS and their inter-individual variations, which are useful in TMJ prosthesis design.

Keywords:

• kinematic characteristics
• preponderance coefficient
• articular tubercle slope
• kinematic standardisation
• prosthesis

Acknowledgements

The authors wish to thank the 32 volunteers who accepted the protocol and expressed their interest in the results for their contribution. They also want to thank ‘CNRS UMR5227 – Laboratoire Mouvement Adaptation Cognition’ of Bordeaux University for its collaboration in validating the experimental protocol.