Tongue thickness is associated with masticatory performance of perioral muscles: Ultrasonographic study of perioral muscle characteristics in healthy young subjects

Background Mastication is a complicated task that involves the teeth and perioral muscles, such as the tongue and lip. Previous studies have shown correlations between masticatory performance and perioral muscle strength (eg tongue pressure) and between masticatory performance and occlusal forces. Objective To investigate the relationships between masticatory performance and perioral muscle characteristics. Methods Forty‐nine healthy young subjects (men: 24 and women: 25) with Eichner classification group A were included in this cross‐sectional study. Age, body weight, masticatory performance, masseter muscle thickness, masseter muscle echo intensity, cross‐sectional area of geniohyoid muscle, geniohyoid muscle echo intensity, tongue thickness (TT) and tongue echo intensity were assessed. Masticatory performance was evaluated using a colour‐changeable chewing gum. The thickness and echo intensity of the masseter muscle, geniohyoid muscle and tongue were observed using an ultrasonic diagnostic apparatus. Stepwise multiple regression analysis was conducted to examine relationships between perioral muscle characteristics and masticatory performance. Results Tongue thickness (P