国人辽宁地区上颌磨牙的活体研究

Study for the Living Maxillar Molar of Chinese in Liaoning Area

本研究对238名(男110女128)年令在18～43周岁,国人辽宁地区青、中年的上颌磨牙1070颗,其中第一磨牙(M_1)476颗.第二磨牙(M_2)476颗,第三磨牙(M_3)118颗进行了观测。测出了上颌磨牙的牙尖型在各类磨牙的分布状态及牙冠的二种退化形式各自表现的特征,取得了各项有关数据;测出了上颌磨牙中各类磨牙的卡氏征阳性率及卡氏征出现各形的频率。讨论中以国人活体牙各项数值与国内、外各有关数值进行了比较,得出活体牙与尸牙的异同及人种间的差异,并对磨牙形态及卡氏征的形态学进行了扼要地探讨。

On this study 1,070 maxillar molars of 238 people have been observed.They were the young and middle aged from 18-43 and lived in Liaoning area.Among 1,070 molars the first molars(M_1)were 476,the second molars(M^2)476 and the third molars(M^3)118 in number. The distribution of the cusps patterns among various molars,two kinds of the crown degeneration,and the Characteristics Showed by themselves were invextigated and the related data obtained.The poaitive rate of Carqbellis'sign for various molars among maxillar molars and the frequency of Carabellis'sign occured in various typeds were also measured.In the discussion the various values of chinese living teeth were compared with those concerned with foreigners and chinese in other areas.Therefore the differences and similarities between the living teeth and the differences and similarities between the living teeth and the corpseteeth,the distinctions among the races were revealed.In addition,the morphology of molar type and Carabellis'sign were investigated brietly.