Abstract
Clinically, the standard value for maximal mouth opening has been detined as either a 35- to 40-mm incisal edge distance or three fingers, but these values have, for the most part, been used empirically.
A total of 446 men and 470 women between 20 and 69 years of age were examined to study the relations been maximal mouth opening and age, stature, sex, mouth width, mandibular length, and three-finger width. Persons with no history of temporomandibular joint diseases and pain or dysfunction in the masticatory system were examined.
The results were as follows:
1. The mean values for maximal mouth opening differed significantly between men and women.
2. Maximal mouth opening was found to be correlated with stature, age, mouth width, mandibular length, and three-finger width.
3. Maximal mouth opening was found to be correlated with stature, sex, age, mouth width, and mandibular length on multiple regression analysis.
4. Maximal mouth opening can be estimated on the basis of stature and sex by multiple regression analysis: maximal mouth opening of men=stature (cm) ×0.206+20.7, maximal mouth opening of women=stature (cm) ×0.206+18.5.
