前歯部排列における歯軸変化の認識に関する研究

抄録

This investigation was carried out to determined what the average man in the street considered to be a natural row of teeth. Models of artificial teeth were made in which the arrangement of anterior teeth was varied, and then shown to a group of dentists and a group of nonprofessionals. Each group was asked to state at what point they felt the teeth looked unnatural and the asymmetry of the teeth. The former was dubbed the point of perceptibility, the latter, the point of discrimination. The points for both groups were compared to determine if differences existed.
The results were as follows:
1. Only slight changes gave the nonprofessional group a feeling of unnaturalness while this feeling in the group of dentists required a somewhat lager alteration.
2. In the case of central incisors, the point of perceptibility for both groups was the same. However, in the case of lateral incisors and cuspids, the point of perceptibility for the group of dentists was significantly higher than that of the nonprofessionals.
3. The degree of change which nonprofessionals considered affected the asymmetry of the teeth was from 1.5 to 2.5 times that of the dentists. It was clear that for any tooth and any change, the point of discrimination for the nonprofessionals was higher.