抄録
A series of studies has been conducted at our department to investigate the relationship between the condition of the stomatognathic system and the systemic condition, on the principle that the stomatognathic system must be regarded as a part of the whole body. As a part of these studies, the gravity fluctuation and activity of antigravity muscles were investigated to estimate the effects on upright posture.
With reference to Shimada's report, the author measured the changes in the gravity fluctuation and activity of antigravity muscles to estimate the effects of the prolonged retention of anterior or lateral mandibular deviation. The results were as follows:
1. Gravity fluctuation tended to increase beyond the normal range of variation when the mandible deviated anteriorly or laterally to the right or left. This parameter tended to increase more with lateral deviation than with anterior deviation.
2. Muscular activity of the anterior temporalis, middle sternocleido-masteoideus, upper trapezius, and lateral gastrocnemius tended to increase beyond the normal range of variation with the mandible deviation. The increase tended to be greater with lateral deviation to the right or left than with anterior deviation.
