Abstract
Relacement of temporary with permanent teeth was studied on 1400 male and female subjects, aged 6 to 15 years old and living in Yunoura-machi, Kumamoto Prefecture and 1098 male and female sudjects, aged 6 to 15 years old and living in island Amakusa, Kumamoto Prefecture. Comparison was made with the data obtained respectively from groups of 1124 male and female subjects, 6 to 15 years old and living in Kitsuki city as examined in 1958 by Anan, and also from groups of 1746 male and female subjects, 6 to 15 years old and living in Kumamoto city as examind in 1950 by Ninomiya. The total numbers of being 5368 of male and female sex. The results were summarized as follows. 1. The average numbers of existing deciduous teeth Yunoura-machi Amakusa district} : Male>Female Male : Kitsuki city>Yunoura-machi<Amakusa district Female : Kitsuki city≒Yunonra-machi≒Amakusa district Male and Female : Yunoura-machi<Kumamoto city (1950, Ninomiya) 2. The average numbers of erupted permanent teeth Yunoura-machi Amakusa district} : Male>Female Male : Kitsuki city>Yunoura-machi<Amakusa district Female : Kitsuki city≒Yunoura-machi≒Amakusa district Male and Female : Yunoura-machi<Kumamoto city (1950, Ninomiya) 3. The average ages for permanent teeth eruption were expressed as follows Yunoura-machi Amakusa district} : Male>Female Male : Kitsuki city>Yunoura-machi<Amakusa district Female : Kitsuki city≒Yunoura-machi≒Amakusa district Male and Female : Yunoura-machi<Kumamoto city (1950, Ninomiya)
