Abstract:

Objective:The aim of this studywas to establish the average of superfacial massetermuscle of young femaleswith normal oc- clusion, and further supply a clue for dentists to evaluate the muscle function of patients with malocclusion.Methods:Totally 31 young females were investigated in this study, whose mean age was21years and 4 months old. Ultrasound technique was applied to obtain the ultrasound parameters of images, including area, width, mean thickness, maximal thickness of the cross-section and the length of the vertical-section of the massetermuscle under relaxing, maximal clenching and maximal protruding condition. The data were analyzed using ANOVA analysis.Results:The mean value and standard deviation of every parameterwere figured out and it was found that there was a significant difference between relaxing and maximal clenching as well as maximal protruding.Conclu- sion:The result indicates that ultrasonic technique is an effective method for describing superfacial masseter muscle morphology and diagnosing its function.

Key words: superfacialmassetermuscle, ultrasound, mandibularpositions