Effect of the Protrusive and Laterotrusive Occlusal Scheme on the Electromyographic Activity of the Mandibular and Cervical Muscles

Aler Fuentes del Campo & Rodolfo Miralles

Summary

There is a close relationship between electromyographic activity (EMG) and dental occlusion. This narrative review presents evidence regarding to the effect of protrusive and laterotrusive occlusal guidance on the EMG activity of the mandibular and cervical muscles, in subjects with natural dentition. During mandibular movement with protrusive guidance, the EMG activity of the anterior temporal, masseter, and sternocleidomastoid muscles was significantly lower in protrusive tooth clenching and grinding compared to the activity recorded during maximum tooth clenching in maximum intercuspation (MIC). In contrast, the activity of the medial pterygoid muscles was similar to that recorded in MIC. However, the activity of the lateral pterygoid and suprahyoid muscles was significantly higher compared to the activity recorded in MIC. During mandibular movement with laterotrusive guidance, EMG activity was significantly lower with canine guidance (CG) compared to group function (GF) in the anterior temporal, posterior temporal and sternocleidomastoid muscles, being similar between CG and GF in the masseter muscles, suprahyoid, infrahyoid, diaphragm and external intercostals. The different EMG patterns observed in protrusive and laterotrusive could be due to a differential modulation exerted by peripheral and central neuromuscular mechanisms in the group of alpha motoneurons that control the activity of these muscles that integrate the craniocervical-mandibular unit.

KEY WORDS: electromyography, dental occlusion, masticatory muscles, neck muscles.

How to cite this article

FUENTES DEL CAMPO, A. & MIRALLES, R. Effect of the protrusive and laterotrusive occlusal scheme on the electromyographic activity of the mandibular and cervical muscles. Int. J. Odontostomat., 18(4):406-414, 2024.