Effect of balancing-side occlusion on the ipsilateral TMJ dynamics under clenching.
The effect of balancing-side occlusal contact patterns on ipsilateral TMJ dynamics was evaluated in this study. Vertical displacement of the balancing-side lower second molar during clenching at canine edge-to-edge position, with 0 and 1 mm of inter-canine distance, was measured for 42 normal subjects in relation to their balancing-side occlusal contact. Balancing-side occlusal contact was classified into four following patterns; (1) simultaneous balancing-side and working-side contact (without clenching); (2) balancing-side contact (with clenching only); (3) no balancing-side contact (with or without clenching); and (4) exclusive balancing-side contact (no working-side contact). The vertical displacement of the balancing-side condyle, calculated from the displacement of the balancing-side second molar, showed three different types of displacement pattern. These three types showed distinctive incidence in relation to the pattern of balancing-side occlusal contact. It was revealed that balancing-side occlusal contact can affect the ipsilateral TMJ dynamics.
Minagi
S
S
Department of Removable Prosthodontics, Okayama University Dental School, Japan.
Ohtsuki
H
H
Sato
T
T
Ishii
A
A
D000328:Adult; D003481:Cuspid / Q000033:anatomy & histology; D003766:Dental Occlusion; D003767:Dental Occlusion, Balanced; D005260:Female; D006801:Humans; D015994:Incidence; D007574:Jaw Relation Record / Q000295:instrumentation; D008297:Male; D008335:Mandibular Condyle / Q000033:anatomy & histology; D008410:Masticatory Muscles / Q000502:physiology*; D008963:Molar / Q000033:anatomy & histology; D009119:Muscle Contraction / Q000502:physiology*; D013704:Temporomandibular Joint / Q000033:anatomy & histology / Q000502:physiology*; D014716:Vertical Dimension