Relationship between mandibular lateral deviation and condylar path asymmetry

Abstract

I investigated the effect of mandibular lateral deviation and condylar path on mandibular border movement. The subjects included 10 men and 10 women with permanent dentition and no temporomandibular dysfunction. Standard PA radiographs were taken in a cephalostat, and the extent of lateral skeletal deviation was measured. Mandibular border movements were recorded at six degrees of freedom during opening, protrusion, retrusion and lateral excursion with a Gnatho-Hexagraph JM-1000. The measurement point of the condyle was located on the kinematic axis. Condylar movement was evaluated along the 3-D linear path of the condyle, and mandibular rotation was determined at maximum opening and inclination of sagittal condylar path during mandibular protrusive movements.
The correlation between the bilateral difference in the 3-D linear path of the condyle at maximum opening and the lateral skeletal deviation was significantly positive (p<0.05). The condylar path length had a tendency to be longer on the deviation side than on the other side. However the correlation between the bilateral difference in mandibular rotation and the lateral skeletal deviation was significantly negative (p<0.05). The mandibular rotation had a tendency to be smaller on the deviation side than on the other side. No significant differences were detected in the other parameters examined. These results suggest that lateral skeletal deviation affects bicondylar path length. Shika Igaku (J Osaka Odontol Soc) 1997 Sept； 60(3)：205-210．