Statistical Observation on Stomatognathic Function in the Twenties

Abstract

A number of clinico-statistical observation on temporomandibular arthrosis reported that the incidence was the highest in the adults in the twenties. This lead us to pinpoint to the age of twenties and observe the status of stomatognathic system to examine the way temporomandibular arthrosis had developed.
The adults concerened the study were 75 for male and 45 for female in the twenties, each of whom was questioned and tested. Sirognathograph Analysing System was used to the analysis of chewing movements. It resulted in discovering symptoms of temporomandibular arthrosis in 61.2% male and 55.6% female. Clinically, patients presented with the noise in general and the pain especially among female. The patients with symptoms of temporomandibular arthrosis had the normal maximum opening volume, the slightly increased index of DMFT, the reduced Type I pattern in the pattern classification (Kuwahara classification) of frontal projection of chewing movements. The incidence of reverse pattern, crossover pattern or both was high in male patients. Furthermore, the male patients with symptoms of temporomandibular arthrosis had the reduced maximum opening and closing velocity and occlusal phase period, while they gave the increase in the cycle, opening phase period, closing phase period and each coefficient of varia-tion.