Objectives:
As part of this study, a comparative analysis of the temporal and masseter muscle electrical activity at rest and during mandible excursion positions (protrusion, laterotrusion and maximal occlusion) was performed among patients aged 21 to 68 years.

Methods:
Each of three groups: opioid addicts, alcohol addicts and the control group – consisted of 30 individuals (90 individuals in total, including 37 females and 53 males). Electrodes were placed on the masseter venters and mandibular movements were executed: right/left lateral, protrusion, intercuspation, rest and MVC. Then the same routine was applied to the anterior parts of temporal muscles.

Results:
Based on EMG data in alcohol addicts, higher electrical activity of masseters and temporal muscles was observed during the mandible excursions, compared to the control group. In comparison of opiate addicts to healthy controls, no statistical significance was observed in electrical activity of masseter and temporal muscles.

Conclusions:
On the basis of the conducted research, a conclusion can be drawn that alcohol addiction significantly affects the function of the largest muscles of the stomatognathic system.