Abstract
It has been reported that during mandibular tapping movements the head moves in functional coordination with the mandible in subjects with a normal occlusion and free of TMD symptoms. However, whether this finding can be applied to TMD patients remains unclear.
The purpose of this study was to confirm the coordination of head and mandibular movements during tapping in TMD patients. Using the Trimet system, we measured tridimensionally both the movement of the head and the mandible by tracking upper and lower incisal points respectively during tapping movements, then analyzed chronometrically the vertical component of these movements.
We found that the incidence of coordinated head and mandibular movements in TMD patients was lower than in normal subjects.
Our findings confirmed the existence of coordination between the head and mandibular movements during tapping, and conclude that it is different for normal subjects and TMD patients. Our results raise the question on whether there is a relation between the presence and intensity of the TMD symptoms and the decrease in the incidence of the coordinated head and the mandible movements during tapping in TMD patients.
