Abstract
Purpose : The purpose of this questionnaire study is to explore how the Japanese think of a "smiling face" featuring the showing of the teeth. Subjects and methods : The study included two groups of subjects. One was a group of Hokkaido University students named the "laypeople group" consisted of 88 students, and the other was a group of 6^<th> grade dental school students named the "dental student group" consist of 55 students. We carried out a questionnaire survey with these students of the two groups to understand "how they think of a smiling face appears, as compared with a normal, non-smiling face?" Results : In both groups, around 90% of subjects in both groups listed an elevated angulus oris, and about 80% of subjects listed Changing eye shape and turned-down lateral angle of eyes. Only 40% of laypeople students and 60% of dental students listed "showing teeth" on the smiling face. Conclusion : 1. Japanese involved in the research here tend to characterize the smiling face with changing appearances of the eyes and mouth. 2. Both the laypeople and dental student groups may consider that the smiling face as not shown with exposing the teeth.
