Measurement in vivo of masticatory mucosal thickness with 20 MHz B-mode ultrasonic diagnostic equipment.

Analysis of the movement of the denture foundation under function is very important for construction of a denture. For this analysis, the thickness of the masticatory mucosa gives the required quantitative information. The thickness measurements were taken from 21 oral sites in 100 edentulous patients, by means of 20 MHz B-mode ultrasonic equipment. The average thickness of the masticatory mucosa ranged from 1.92 mm to 2.38 mm at the upper edentulous ridge and from 1.45 mm to 1.58 mm at the lower edentulous ridge. The center of the palate had the thinnest mucosa and the lateral area of the palate had the thickest among all the measuring points. Contrary to what is often believed, a decrease in mucosal thickness with age was not observed by one-way analysis of variance. Furthermore, as the degree of ridge reduction increased, a decrease in the mucosal thickness was found by one-way analysis of variance at only two of the 14 measuring sites on the ridges. At four of the 21 measuring sites, male patients had significantly thicker mucosa than did females, and the correlation coefficients of the thickness of mucosa between right and left sides in the palate were higher than those in residual ridges.