Nocturnal electromyographic evaluation of masseter muscle activity in the complete denture patient.

Nocturnal oral activity was evaluated in 12 complete denture wearers by means of EMG measurements of the masseter muscle. Patients who had worn dentures for at least 6 months were selected. EMG levels were compared when subjects slept with and without the dentures in the mouth. Three subjects appeared to have reduced EMG values when sleeping with the dentures. However, no overall group trends or significant differences were obtained. High variability in nightly EMG values could not be explained by a post hoc analysis of patient oral symptoms or denture characteristics. Efforts should be directed at improved methodology to study the specific mechanism of the effect of denture wearing on nocturnal muscle activity levels. Additional knowledge is needed on the occurrence and effects of parafunctional habits in the edentulous patients.