Body position and jaw posture effects on supra- and infrahyoid electromyographic activity in humans.

The purpose of this study was to record the pattern of electromyographic (EMG) activity of supra- and infrahyoid muscles at different body positions and jaw posture tasks. The sample included 22 healthy subjects with natural dentition, bilateral molar support, and absence of posterior occlusal contacts during mandibular protrusion. Bipolar surface electrodes were located on the left supra- and infrahyoid muscles for EMG recordings.

Effects of laterotrusive occlusal scheme and body position on bilateral sternocleidomastoid EMG activity.

This study was conducted to determine the effects of laterotrusive occlusal scheme and body position on bilateral sternocleidomastoid electromyographic (EMG) activity. The study was performed on 20 healthy subjects with natural dentition and bilateral molar support. During laterotrusive occlusal excursion (working side), each individual had to present canine guidance on one side and group function on the opposite side, without balancing-side contacts.

Vertical dimension. Part 2: the changes in electrical activity of the cervical muscles upon varying the vertical dimension.

This study was conducted in order to determine the effect of vertical dimension variation on the electromyographic (EMG) activity of the sternocleidomastoid and trapezius muscles. The study was performed on 15 healthy subjects. Basal tonic electromyographic (BT-EMG) recordings were performed by placing surface electrodes on the left sternocleidomastoid and trapezius muscles.