6 712名少年儿童恒牙萌出时间和顺序的调查研究

目的:调查分析西安市少年儿童恒牙萌出的时间、顺序和性别差异,为口腔医师进行咬合诱导等治疗提供理论参考。方法:在西安市8所幼儿园、小学和中学中整群抽取6712名年龄为3～15岁的少年儿童,收集恒牙萌出横断面调查资料,其中男性3604名,女性3108名,对各项数据进行统计分析。结果:左右两侧同名牙同时萌出,除第一、第二前磨牙外,下颌恒牙萌出早于上颌同名牙;大多数恒牙的萌出时间女性早于男性,萌出顺序也有所不同。结论:结果与以前国内其他地区的调查结果有一定不同。

Eruption times and sequence of permanent teeth in 6 712 children and young adolescents

Objective:To determine the differences of age, eruption sequence and gender of permanent teeth in children and adolescents in Xi'an, China. Methods:Cross-sectional data on permanent teeth eruption were collected from children aged 3~15 in pre-school, primary and secondary school. The subjects were drawn by multistage random sampling from the school registers. There were 6 712 subjects involved in present survey, including 3 604 boys and 3 108 girls. The data were subjected to probit regression analysis. Results:The median age of tooth eruption in girls was earlier than that 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 was 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.