51(P41) Morphological analysis of the dental arches in Japanese adults with normal occlusions

• Published in: Anthropological Science Vol. 119; no. 3; p. 286
• Main Authors: INUI-YAMAMOTO C, UEDA K, NAKATSUKA M, KUMABE S, AN C, IWAI Y
• Format: Journal Article
• Language: Japanese
• Published: Anthropological Society of Nippon 2011
• ISSN: 0918-7960

Life-style and dietary habits have been altered markedly during the last several decades in Japan. Generally, it is thought that variations in tooth, dental arch, and jaw sizes have become common due to morphological changes. However, there have been only a few studies to evaluate the changes in the dental arch morphology. Therefore, we investigated plaster dental casts obtained from Japanese adults in 1947 (i.e., group I), 1962 (i.e., group II), 1977 (i.e., group III), 1992 (i.e., group IV), and 2007 (i.e., group V). We measured the length and width of the dental arches of the maxillary and mandibular dental casts. We observed that the length of the maxillary dental arch of group II was shorter than that of groups IV or V. The length of the mandibular dental arch of group II was also shorter than that of groups I or IV. On the other hand, there were no significant differences in regard to the width of the maxillary and mandibular dental arches. The length of the maxillary and mandibular dental arches of group II tended to be smaller than that of the other groups. These results suggest that the dental arch morphology was significantly changed for several years.