Comparison of mean fiber areas of masseter muscle fiber types in male and female subjects by vertical skeletal malocclusion groups. Data for mean fiber area values in μm2 for skeletal open bite (14 males and 36 females), normal vertical dimension (16 males and 42 females), and deep-bite malocclusion categories (16 males and 15 females). Bars represent 1 standard deviation of the mean. Significant differences in mean fiber type area compared between normal, open, and deep bite malocclusion groups were found for type II (P ≤ .0004) and type neonatal—atrial (P = .001) fiber types.
Sciote et al. Human Masseter Muscle Fiber Type Properties. J Oral Maxillofac Surg 2012.