Richards L C, Townsend G C, Brown T, Burgess V B
Department of Dentistry, University of Adelaide, South Australia.
Arch Oral Biol. 1990;35(12):983-9. doi: 10.1016/0003-9969(90)90018-6.
Fourth-order polynomials were used to represent dental arch morphology in 29 monozygous and 19 dizygous like-sexed twin pairs, and in 45 unrelated individuals. The polynomial coefficients provided an accurate description of dental arch morphology with the quadratic (chi 2) and quartic (chi 4) terms reflecting arch shape and the linear (chi) and cubic (chi 3) terms summarizing asymmetry. There were no significant differences between the groups in either the quadratic or quartic terms. Values of correlations between polynomial terms indicated that there was no consistent relationship between maxillary and mandibular arch shape or asymmetry. Intraclass correlations between twins suggested that genetic factors contributed to variation in maxillary arch shape and to a lesser extent to variation in mandibular arch shape but not to arch asymmetry.
采用四阶多项式来表示29对同卵和19对同性异卵双胞胎以及45名无血缘关系个体的牙弓形态。多项式系数能准确描述牙弓形态，其中二次项（χ2）和四次项（χ4）反映牙弓形状，线性项（χ）和三次项（χ3）总结不对称性。两组在二次项或四次项上均无显著差异。多项式项之间的相关性值表明，上颌和下颌牙弓形状或不对称性之间不存在一致的关系。双胞胎之间的组内相关性表明，遗传因素对上颌牙弓形状的变异有贡献，对下颌牙弓形状变异的贡献较小，但对牙弓不对称性没有影响。
