Abstract
This is one of a series of reports which compare the oral conditions of Tibetans from three different areas.
As regards occlusal features, crowding shows whether their jaws developed well or not.
1. In Karakoram, teeth were too abrased to know the original occulusion of the villagers' teeth because of fine sand mixed in cooking water.
2. In northwest Nepal, the crowding rate was smaller than than of Yunnan Province. On the other hand, the overjet rate decreased much among the villagers who were more than fourteen years old.
3. In Yunnan Province, the crowding rate was two times greater than in Northwest Nepal.
Much crowding was found in youngsters; one third of those five to fourteen years old proved to have crowding. Greater overjet rate was found among villagers who were older than fifteen years old than those who were five to fourteen years old.
4. As malocculusion data from a Japanese report on a survey of dental diseases were examined from the view point of orthodontic requirements, it is impossible to compare the malocclusion conditions with those from the three Tibetan areas.
The crowding rate found among five-to-fourteen-years old villagers in Yunnan Province was similar to that of Sakuta's data.
