Swedish dental journal. Supplement
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Comparative Study Clinical Trial Controlled Clinical Trial
Electromyography and bite force studies of muscular function and dysfunction in masticatory muscles.
Electromyographic (EMG) activity versus bite force was studied during a gradually increased isometric contraction up to maximal effort for patients with painful masseter muscles and referents. The masseter muscle, the anterior temporal muscle and the descending part of the trapezius muscle were chosen for the recordings. Bite force was registered with a bite force sensor placed between the first molars. ⋯ The amplitude probability distribution analysis revealed that the patients used greater relative masticatory forces than the referents during the chewing of an almond for all probability levels analysed below the peak load of the masseter muscles. Rough estimates of the peak masticatory forces in Newton (N) were for chewing an almond 364 N (referents); 373 N (patients) and for gum-chewing 239 N (referents); 238 N (patients) as regards the masseter muscle. The values were similar for the anterior temporal muscle.