青少年安氏Ⅰ类恒牙列牙冠超硬石膏模型宽度:与1959年国人离体牙数据参数的比较

Angel's Ⅰmesiodistal crown dimension in permanent dentition of super-hard plaster model in teenagers:a comparison with data parameters of ex vitro teeth of Chinese people in 1959

目的:了解国内当代青少年恒牙列牙冠的宽度,将结果与1959年王惠芸所作的牙冠宽度值相比较,以探讨国人牙齿的变化情况。方法:第四军医大学口腔医院正畸科1999-01/2003-12测量224例安氏Ⅰ类恒牙列青少年牙牙合超硬石膏模型的各牙冠宽度,进行统计分析。结果:国内当代青少年牙冠宽度由大到小依次为(U:上颌,L:下颌,其后数字为牙位):U6>U1>U3>U4>U2>U5,L6>L4>L5>L3>L2>L1,不包括第二磨牙。与1959年王惠芸所测国人离体牙牙冠宽度值比较,除下颌第一磨牙差别不显著外,其他牙位平均牙冠宽度均增大。结论:不同时期的健康营养状况使国内当代青少年牙冠宽度较以前有所增加。人类在演化过程中,各牙位受到的影响条件不一致。上下颌骨的生理差异可能导致了上颌牙量的增加大于下颌牙量的增加。

AIM:To know the mesiodistal crown dimensions in permanent dentition of Chinese teenagers at present,and analyze the dimensions in comparison with the data finished by Hui-yun Wang in 1959 so as to probe into transformation of mesiodistal crown dimensions in permanent dentition of Chinese people. METHODS:Between January 1999 and December 2003 in the Department of Orthodontics, Stomatological Hospital,Fourth Military Medical University,angle's Ⅰmesiodistal crown dimensions in permanent dentition of super-hard plaster models were measured in 224 teenagers for next statistical analysis. RESULTS:The sequence of mesiodistal crown dimensions in Chinese teenagers nowadays was as follows(U:upper teeth,L:lower teeth, and the following numbers of U and L were position of teeth):U6 >U1 >U3 >U4 >U2 >U5,L6 >L4 >L5 >L3 >L2 >L1,excluding the second molar.The averages of mesiodistal crown dimensions increased remarkably as compared with the numerical values that Hui-yun Wang measured in 1959,except for the first molar in the mandible. CONCLUSION:The mesiodistal crown dimensions of present Chinese teenagers augment with improvement of health and nutrition.Teeth are exerted differently due to various influence during human evolvement.Physiological differences between mandible and maxilla may lead to the more increase of tooth size in maxilla than in mandible.