Kf. Genaro et al., ELECTROMYOGRAPHIC ANALYSIS OF LIP MUSCLE FUNCTION IN OPERATED CLEFT SUBJECTS, The Cleft palate-craniofacial journal, 31(1), 1994, pp. 56-60
EMG activity of the upper lip was measured with bipolar surface electr
odes during speech and nonspeech tasks in order to assess labial funct
ion in subjects with repaired clefts. Eighteen patients between 15 and
23 years of age with repaired unilateral cleft lip (isolated or combi
ned with repaired cleft palate) were compared to 24 matched noncleft s
ubjects. Data analysis demonstrated that the amplitude of action poten
tials of the upper lip was significantly greater in the cleft group. W
e hypothesize that the enhanced activity of the repaired upper lip dur
ing function may contribute to the facial growth abnormalities usually
seen in the cleft population.