Electronic analysis of mandibular movements during speech depending on the skeletal class

Speech is one of the most important functions of the stomatognathic system. The aim of the study was to assess mandibular movements during speech depending on the skeletal class and the mutual relationship between the incisors. Forty-nine patients without functional disorders of the masticatory organ were examined. In subjects with skeletal class I, the mean length of condylar motion in the sagittal plane was 0.8 mm; in the case of class II, it was – 1.2 mm; and for class III, it was 0.9 mm. There was no statistically significant correlation between the examined parameters of mandibular translation movement during speech with gender or skeletal class. However, the correlations between the maximum mandibular rotation angle and the position of the incisors were statistically significant.