THE MASTICATORY SYSTEM OF THE OBESE: CLINICAL AND ELECTROMYOGRAPHIC EVALUATION

Masticatory performance is determined not only through the speed of mastication, or by the quantity of food ingested; it also depends on the structures and functional integration of the stomatognathic system (SS).

This study investigated differences in the SS and orofacial motricity between obese and normal--weight women.

A total of 18 obese women, with an average age of 28 ± 7.3 years and an average body mass index (BMI) of 37.4 ± 5.1 Kg/m2, and 18 normal--weight women, with an average age of 26 ± 7.6 years and an average BMI of 20.7 ± 1.8 kg/m2, took part in the study. During the speech therapy evaluation, chewing, the number of chewing strokes, and swallowing were observed. The posture, mobility and tonus of lips and tongue, morphology, mobility and tonus of cheeks were designated as normal or altered. The electrical activity of the anterior temporalis, the masticatory muscle was evaluated for both groups using surface electromyography (EMG), which was expressed in microvolts (pV) and registered as Root Mean Squares.

Significant differences were found between the two groups in clinical evaluation. In surface EMG, the obese group showed asymmetry of electrical activity of the anterior temporalis.

This study suggests that speech therapist investigation of the SS should be combined with interdisciplinary obesity management.