抄録
The facial muscles are composed ofstriated muscle fibers, as well as other skeletal muscles, and can produce more delicate and complex expressions. We studied 2 facial muscles of 10 Japanese cadavers (8 males and 2 females, average 74.7 years old) by histological techniques. We measured the cross-sectional area of the muscle belly (mm2), number ofmuscle fibers per mm2, total number ofmuscle fibers, and muscle fiber size (μm2). The depressor anguli orism. was predominant for the cross-sectional area and the total number of muscle fibers than other facial muscles. For the muscle fiber size, muscles inserted to the angle of the mouth were larger than those inserted to the lip. The orbicularis oculi and orbicularis oris muscles were the smallest facial muscles. The muscle fiber sizes in the facial muscles were less than other skeletal muscles.
