TY - JOUR
T1 - Masticatory muscle function in patients with spinal muscular atrophy.
AU - Granger, M. W.
AU - Buschang, P. H.
AU - Throckmorton, G. S.
AU - Iannaccone, S. T.
PY - 1999/6
Y1 - 1999/6
N2 - The purpose of this study was to determine whether spinal muscular atrophy affects masticatory muscle strength and mandibular range of motion. A sample of 15 subjects with spinal muscular atrophy was compared to a sample of age-matched and sex-matched controls. Maximum bite force, masticatory muscle electromyography activity, mandibular ranges of motion and masticatory muscle endurance were evaluated. Results showed that maximum bite forces were one-half as great for the sample with spinal muscular atrophy than for the controls, even though their EMG activity was not significantly different. Slopes of the relationship between electromyography activity and bite force were two to four times steeper for patients with spinal muscular atrophy than controls. Maximum opening and protrusion were reduced to approximately one-half control values. Fatigue times of patients with spinal muscular atrophy were reduced by 30% (17.9 seconds versus 11.1 seconds). We conclude that the masticatory muscles of patients with spinal muscular atrophy are weakened, that their muscles are less efficient, and that they fatigue more quickly than controls. In addition, mandibular movements of these patients take place over a more limited range than unaffected controls.
AB - The purpose of this study was to determine whether spinal muscular atrophy affects masticatory muscle strength and mandibular range of motion. A sample of 15 subjects with spinal muscular atrophy was compared to a sample of age-matched and sex-matched controls. Maximum bite force, masticatory muscle electromyography activity, mandibular ranges of motion and masticatory muscle endurance were evaluated. Results showed that maximum bite forces were one-half as great for the sample with spinal muscular atrophy than for the controls, even though their EMG activity was not significantly different. Slopes of the relationship between electromyography activity and bite force were two to four times steeper for patients with spinal muscular atrophy than controls. Maximum opening and protrusion were reduced to approximately one-half control values. Fatigue times of patients with spinal muscular atrophy were reduced by 30% (17.9 seconds versus 11.1 seconds). We conclude that the masticatory muscles of patients with spinal muscular atrophy are weakened, that their muscles are less efficient, and that they fatigue more quickly than controls. In addition, mandibular movements of these patients take place over a more limited range than unaffected controls.
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U2 - 10.1016/S0889-5406(99)70296-9
DO - 10.1016/S0889-5406(99)70296-9
M3 - Article
C2 - 10358253
AN - SCOPUS:0033143845
SN - 0889-5406
VL - 115
SP - 697
EP - 702
JO - American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics
JF - American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics
IS - 6
ER -