The purpose of this paper was to study clinical and electromyographic changes of masticatory system associated with experimental prematurity. This experiment was performed on 3 male subjects, age from 26 to 34 years old, and each possessing a natural dentition without any disorder of temporomandibular joint and masticatory muscles. To induce artificial prematurity on their natural dentition, single high occlusal inlay were placed in their lower molar. Before and after setting inlays, they were investigated electromyographically and clinically.
Immediately after placing of inlay, all subjects experienced bruxism such as clenching and grinding, either consciously or even inconsciously. After three days of experimental period, inlays were removed and all of them showed glittered attritional surface. Electromyographically activity of masseter and temporal muscles were inhibited during chewing (peanut), particularly on experimental side. It seems that the musclar inhibition may be a protective reaction to protect the prematufy tooth from excessive forces.