Abstract
An anthropological study of the oral cavity in various areas of Japan and neighboring countries has been conducted to clarify racial lineages. The aim of this study is to clarify the oral traits of Amami population. Plaster models were taken from 131 males and 111 females ages 15 to 18, and then measured. Each measurement of the dental arches and palates of the Amami population was compared between males and females. Each measurement of the Amami population was also compared with that of the Japanese (Ishigakijima, Okinawa, Tanegashima, Kitakyushu population, Iki), Taiwanese, Taiwan Aboriginals (Ami, Bunun, Paiwan, Rukai tribes), Central American Indian Jicaques and Balinese. Dental arch lengths were significantly greater in the Amami than in the Taiwan Aboriginals and the Jicaques. Dental arch breadths were smaller in the Amami than in the Jicaques. Lengths of the dental arch were greater in the Amami than in the Okinawans, the Ami, the Bunun, the Paiwan and the Balinese. Palatal heights were significantly higher in the Amami than in the Taiwanese, the people from Iki and the Jicaques, and lower than in the Paiwan and the Rukai. Length of the sutura palatina mediana was shorter in the Amami than in the people from Ishigakijima, the Okinawans, the Balinese, and longer than in the Paiwan. Palatal arch lengths were narrower in the Amami than in the Balinese. Palatal breadths were smaller in the Amami than in the people from Ishigakijima, the Taiwanese, the Taiwan Aboriginals, the Jicaques and the Balinese. Mandibular alveolar breadths were smaller in the Amami than in the people from Ishigakijima and Tanegashima, the Taiwanese, the Taiwan Aboriginals and the Jicaques. These findings and the results of a cluster analysis and neighbor-joining method, and multi dimensional scaling (MDS) suggest that oral traits of the Amami population differ from those of the Taiwan Aboriginals and the Jicaques, and are similar to the Japanese, and was related to the Taiwanese.
