Dental Anthropology on the Formation of Sundadont

1)使用日本大学牙科学院松岛分校的牙科模型，对巴布亚新几内亚高原居民进行了计量和非计量测量。(1)用我们的评分系统观察了上切牙的非计量特征，包括切牙结节和脊柱突。与澳大利亚原住民一样，高地居民的这些特征出现的频率很高。在与斐济、萨摩亚、基里巴斯、帕劳等太平洋地区人群的比较中，还研究了其他非计量性状。新几内亚高地人群第6尖牙尖频率较低。(3)对下第一磨牙牙尖面积的计量学研究表明，高地人群远中牙尖牙尖面积明显小于澳大利亚人。2)对云南省中国少数民族的牙齿特征进行了调查。昆明古脊椎动物研究所季学平研究员于1999年5月进行了初步研究。这项调查于2000年2月27日至3月8日在云南省元江市进行。少数民族来自哈尼族和傣族。从这些部落中抽取了200个牙模和龋齿频率。牙科模型现在正在实验室里进行测量。

1) Metric or non-metric measurement of Papua New Giniea Highlanders were carried out with the use of dental casts housed in Nihon University School of Dentistry at Matsudo.(1) Non-metric traits of the upper incisors including incisal tubercles and spinal process were observed with our scoring system. Highlanders had high frequencies of these traits as seen in Australian Aborigines. However, the frequency of shovel shaped incisor was low.(2) Other non-metric traits were also investigated in the comparison with some Pacific populations including Fiji, Samoa, Kiribati, Palau. The low frequency of 6th cusp were noted in New Guinea Highlanders.(3) Metric study of the cuspal area of the lower first molar demonstrated that distal cusps in Highlanders were significantly smaller than Australians. This suggested that the distal part of the first molar in Highlanders were reduced in their micro-evolution.2) Investigation on the dental characters in minorities in China living in Yunnan Province was conducted. Preliminary research was carried out in May, 1999 with Chinese researchers, Ji Xueping, Kunming Paleovertebrate Institute. The survey was held in Yuenjian in Yunnan Province from February 27 to March 8, 2000. Minority peoples are from Hani tribe and Dai tribe. Dental casts of 200 in total and dental caries frequency were taken from these tribes. Dental casts were now being measured in the laboratory.