Genetic Covariance Structure of Incisor Crown Size in Twins

摘要: Previous studies of tooth size in twins and their families have suggested a high degree genetic control, although there been difficulties separating the various environmental effects. A analysis variation crown permanent incisors South Australian was carried out, with structural equation modeling used to determine relative contributions factors. Maximum mesiodistal dimensions maxillary mandibular were recorded from dental models 298 pairs twins, including 149 monozygous (MZ) dizygous (DZ) pairs. The revealed that: (i) an adequate fit required additive unique components; (ii) augmenting model non-additive did not lead significant improvement fit; (iii) evidence shared influences upper central males; (iv) component constituted general factor loading on all eight teeth, group factors antimeric teeth; (v) effects mostly variable-specific; (vi) most loadings could be constrained equal, indicating symmetry between left right sides; (vii) estimated heritability incisor varied 0.81 0.91.