Effect of Two Maxillary Splint Occlusal Guidance Patterns on the Electromyographic Activity of the Jaw Closing Muscles

摘要

The present study found a reduction of anterior temporalis and masseter muscle EMG activity during both lateral excursive movement and excursive clenching on a maxillary splint. The average reductions during the movement phase were 81.8 + or - 14.0% with canine guidance and 81.6 + or - 19.2% with first molar guidance. The average reductions during the excursive clenching phase were 44.7 + or - 26.7% with canine guidance and 42.6 + or - 29.7% with first molar guidance. There was no statistically significant difference in the reductions of EMG activity for the two different guidance patterns. In this study there was a considerable variance in actual EMG scores between subjects. This intersubject variability was dealt with by a within subject design using percentage reductions of the EMG activity. These percentage reductions of EMG activity show that clenching during lateral movement reduced jaw muscle activity significantly more than clenching in excursive position for both guidance patterns. The jaw muscle activity was observed to be reduced during lateral movement and excursive position clenching. There was no statistically significant difference in the degree of reduction for either cuspid guidance or first molar guidance on a maxillary occlusal splint.