西安市青少年恒牙萌出时间及恒牙萌出与生长发育关系的调查

Eruption times of permanent teeth and the relationship between the eruption of permanent teeth and the growth status of children and young adolescents in China Xi'an

目的:调查西安市青少年、儿童恒牙萌出的时间、顺序和性别差异,分析恒牙萌出与生长发育间的内在联系。方法:在西安市幼儿园、小学和中学随机选取6755名年龄2～17岁青少年,收集恒牙萌出横断面调查资料,其中男3637名,女3118名,对受试者资料进行统计学分析。结果:女性受试者所有恒牙萌出的平均时间早于男性,萌出顺序也不同;除第一、第二前磨牙外,下颌牙的萌出早于上颌同名牙。大多数恒牙初萌时间与身高、体重间有显著的低度相关关系(P<0.05)。结论:调查结果与以前国内其他地区的调查结果之间存在差异,对临床工作有理论指导意义。

Objective： To determine the age and sequence of eruption of permanent teeth, as well as, the relationship between the eruption of permanent teeth and the growth status of children and adolescents in Xi＇an, China.Method： Crosssectional data on permanent teeth eruption were collected by examining pre-school, primary and secondary school children of 2-17 years of age. The subjects were drawn by multistage random sampling from the school registers. There were 6755 subjects in the sample, 3637 boys and 3118 girls. The data were subjected to probit regression analysis. Result. The median age of eruption of each tooth was earlier in girls than in boys. Although the range of years during which the permanent teeth erupted was similar in both sexes, i.e. 6-12 years, the sequence of the tooth eruption differed. All mandibular teeth, with the exception of first and second premolars in both males and females, tended to erupt earlier than their maxillary counterparts.Conclusion： The findings seem to be different from earlier studies done in the other parts of China.