He argues that toothcrowns and roots have a high genetic component, minimally affected by environmental and other factors.
他认为,牙冠和牙根有很多的遗传成分,受环境和其他因素的影响很小。
2
Most of the third molar embryo had been formed and their toothcrowns had been calcified, the occurrence ratio was 84 0 % in maxilla and 85 2 % in mandible.