Edgar H J H, Lease L R
Maxwell Museum of Anthropology, Department of Anthropology, University of New Mexico, Albuquerque, NM 87131, USA.
Am J Phys Anthropol. 2007 May;133(1):726-34. doi: 10.1002/ajpa.20564.
The expression of dental morphological characteristics is partially genetically controlled, and is assumed to be similar in deciduous and permanent dentitions. However, there are few published data comparing normal morphological variation between the two dentitions in the same individual. For the current study, data were collected from European Americans (N = 54) whose teeth were cast both as children and adults. We observed 19 trait expressions in deciduous and permanent dentitions. Deciduous traits were scored based on Hanihara's and Sciulli's descriptions, while permanent teeth were scored using the ASU dental anthropology system. The two dentitions' scores were compared using Goodman-Kruskal's Gamma (gamma) in the original, commonly used systems as well as in a new, shared scale to which the scores were converted. Observations were also dichotomized in both formats and compared using tetrachoric correlation. We expected high correlations between the two dentitions and for both statistics to yield similar results. For the original scores, gamma correlations vary from -1.0 to 0.68; tetrachoric correlations vary from 0.04 to 0.67. For the shared scale scores, gamma correlations range from -1.0 to 1.0 and tetrachoric correlations range between -0.47 and 0.8. Several traits showed no correlation in either test. Overall, categorical data analysis returned more positive moderate to high correlations than tetrachoric correlation analysis, and shared scale tests resulted in more correlations than did tests of data in the original scoring systems. These results reflect differences in commonly used scoring systems, variation in rarely occurring traits, different strengths of trait expression, and complex genetic/environmental interactions.
牙齿形态特征的表达部分受基因控制，并且假定在乳牙列和恒牙列中相似。然而，很少有已发表的数据比较同一个体中这两种牙列之间的正常形态变异。在本研究中，数据收集自牙齿既有儿童期模型又有成年期模型的欧裔美国人（N = 54）。我们观察了乳牙列和恒牙列中的19种性状表达。乳牙列性状根据ihara和Sciulli的描述进行评分，而恒牙则使用亚利桑那州立大学牙齿人类学系统进行评分。在原始的常用系统以及分数转换后的新共享量表中，使用古德曼-克鲁斯卡尔的伽马系数（gamma）比较两种牙列的分数。观察结果在两种形式中也进行了二分法处理，并使用四分相关进行比较。我们预期两种牙列之间具有高度相关性，并且两种统计方法会产生相似的结果。对于原始分数，伽马相关性从-1.0到0.68不等；四分相关性从0.04到0.67不等。对于共享量表分数，伽马相关性范围从-1.0到1.0，四分相关性范围在-0.47到0.8之间。有几个性状在两种测试中均无相关性。总体而言，分类数据分析得出的中度到高度正相关性比四分相关分析更多，并且共享量表测试产生的相关性比原始评分系统中的数据测试更多。这些结果反映了常用评分系统的差异、罕见性状的变异、性状表达的不同强度以及复杂的基因/环境相互作用。
