The effects of mandibular orthopedic repositioning appliance on shoulder strength.

AbstractThe purpose of this study was to examine the effects of a mandibular orthopedic repositioning appliance (MORA) on human shoulder strength. Twenty volunteer undergraduate college students were randomly selected. The subjects were given oral examinations and two appliances were then constructed for them: A MORA, which repositioned the mandible in three dimensions as described by Gelb,1 and a placebo appliance that did not alter the occlusion. Three bite conditions were then studied for each subject: centric occlusion, centric occlusion with the placebo splint inserted, and the position with the MORA inserted. The data for each subject were taken as he or she was seated in a stabilized chair, and the data were collected using a Cybex II dynamometer. Measurements were recorded for each of the six shoulder movements: abduction, adduction, flexion, extension, external rotation, and internal rotation.Statistically significant results were obtained among the bite conditions for shoulder extension, peak to...