Background and aims. Predicting the teeth eruption time is a valuable tool in pediatric dentistry since it can affects scheduling dental and orthodontic treatments. This study investigated the relationship between the eruption time of first primary and permanent teeth and the variation in the eruption time considering socioeconomic status (SES) in a 9-year populationbased cohort study. Materials and methods. 307 subjects were examined at bimonthly intervals during the first and second years of life and then at six-month intervals until the eruption of first permanent tooth. Eruption times of primary and permanent tooth were recorded for each child. A modified form of Kuppuswamy’s scale was used to assess the SES. Results. Among 267 subjects completed all follow-ups, the eruption time for first primary and permanent teeth indicated a direct strong correlation; in that one month delayed or early eruption of first primary tooth resulted in 4.21 months delayed or early eruption of first appearing permanent tooth (r = 0.91, n = 267, P <0.001). No significant correlation was observed between the eruption time of first primary and first permanent teeth and SES (P = 0.67, P = 0.75, respectively). Conclusion. The eruption timing for the first primary tooth had a correlation with the first permanent tooth eruption timing, while SES did not have any influence on eruption times.

中文翻译：

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介绍

背景和目标。预测牙齿萌出时间是小儿科牙科的宝贵工具，因为它会影响牙科和正畸治疗的时间安排。这项研究在一项基于人群的9年人群研究中，考虑了社会经济状况（SES），调查了第一颗乳牙和恒牙的萌发时间与萌发时间变化之间的关系。材料和方法。在生命的第一和第二年中，每两个月检查一次307名受试者，然后每六个月检查一次，直到第一颗恒牙萌出为止。记录每个孩子的乳牙和恒牙的爆发时间。Kuppuswamy量表的修改形式用于评估SES。结果。在267名受试者中完成了所有随访，第一颗乳牙和恒牙的萌发时间直接相关。第一个乳牙延迟或早萌出一个月，导致首次出现恒齿的延迟或早萌出4.21个月（r = 0.91，n = 267，P <0.001）。在第一颗恒牙和第一颗恒牙的萌发时间与SES之间未观察到显着相关性（分别为P = 0.67，P = 0.75）。结论。第一颗乳牙的萌发时机与第一颗恒牙的萌发时机相关，而SES对萌发时间没有任何影响。在第一颗恒牙和第一颗恒牙的萌发时间与SES之间未观察到显着相关性（分别为P = 0.67，P = 0.75）。结论。第一颗乳牙的萌发时机与第一颗恒牙的萌发时机相关，而SES对萌发时间没有任何影响。在第一颗恒牙和第一颗恒牙的萌发时间与SES之间未观察到显着相关性（分别为P = 0.67，P = 0.75）。结论。第一颗乳牙的萌发时机与第一颗恒牙的萌发时机相关，而SES对萌发时间没有任何影响。