title: Changes in electrical activity of masseter and temporal muscles after temporomandibular joint surgery. A one-year follow up.
abstract: The functioning of the masseter and anterior temporal muscles was recorded by electromyography (EMG) in 15 patients with disc interference of the temporomandibular joints, before surgery and three months, six months and one year afterwards. EMG recordings were made during maximal bite in intercuspal position and while chewing. The mean electrical activity in the masseter and anterior temporal muscles, both on the operated and nonoperated sides, decreased markedly three months after surgery, especially during maximal bite in intercuspal position, but increased to above the preoperative values at the one-year recording in both functions. Statistically, significantly lower activities were seen on the operated side in patients with anterior dislocation of the disc without reduction, as compared to patients with reduction of the disc. The EMG activities of the masseter muscles on the nonoperated side were significantly lower in women and in older patients, as well as in patients with a longer duration of symptoms than in men and younger patients.
authors.affiliation: Department of Prosthetic Dentistry and Stomatognathic Physiology, Institute of Dentistry, University of Oulu, Finland.
authors.forename: A M
authors.initials: AM
authors.lastname: Raustia
authors.forename: K S
authors.initials: KS
authors.lastname: Oikarinen
authors.forename: H
authors.initials: H
authors.lastname: Pernu
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001732:Bite Force; D004576:Electromyography; D005157:Facial Pain / Q000503:physiopathology / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D004204:Joint Dislocations / Q000601:surgery; D008297:Male; D008335:Mandibular Condyle / Q000601:surgery; D008406:Masseter Muscle / Q000502:physiology*; D008409:Mastication / Q000502:physiology; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D010173:Palpation; D016059:Range of Motion, Articular / Q000502:physiology; D012737:Sex Factors; D013703:Temporal Muscle / Q000502:physiology*; D019224:Temporomandibular Joint Disc / Q000601:surgery*; D013705:Temporomandibular Joint Disorders / Q000601:surgery; D013997:Time Factors; D000267:Tissue Adhesions / Q000601:surgery