Tan Sharon H X, Sim Yu Fan, Hsu Chin-Ying S
Ministry of Health HoldingsSingapore, Singapore.
Faculty of Dentistry, National University Health System, National University of SingaporeSingapore, Singapore.
Front Physiol. 2017 Jun 29;8:442. doi: 10.3389/fphys.2017.00442. eCollection 2017.
Striae periodicity refers to the number of cross-striations between successive lines of Retzius in tooth enamel. A regular time dependency of striae periodicity, known as the circaseptan interval, has been proposed. Previous studies on striae periodicity have been carried out on both modern and early humans given its potential applications in forensic age estimations and anthropology. Nevertheless, research comparing striae periodicities across gender groups and populations in different geographical locations, particularly in Asia, is lacking. In this study, we compared the striae periodicities of Heilongjiang and Singaporean Chinese, as well as that of Singaporean Chinese males and females. Results showed that while the median striae periodicity counts of Heilongjiang Chinese and Singaporean Chinese teeth are both 7, Heilongjiang Chinese tend to have lower striae periodicity counts than Singaporean Chinese ( < 0.01). No significant gender difference was observed between the median striae periodicity of Singaporean Chinese Female and Singaporean Chinese Male teeth ( = 0.511). We concluded that the median striae periodicity may statistically differ with geographical location, but not gender, provided that ethnicity and geographical location are held constant. Further studies are required to examine the causes for variation in striae periodicities between geographical locations, as well as to verify the other bio-environmental determinants of striae periodicity.
釉柱横纹周期是指牙釉质中雷丘斯线之间的横纹数量。有人提出釉柱横纹周期存在一种规律的时间依赖性，即所谓的七日周期。鉴于其在法医年龄估计和人类学中的潜在应用，此前已对现代人和早期人类的釉柱横纹周期进行了研究。然而，缺乏比较不同地理位置，特别是亚洲不同性别群体和人群之间釉柱横纹周期的研究。在本研究中，我们比较了黑龙江汉族和新加坡华裔以及新加坡华裔男性和女性的釉柱横纹周期。结果显示，黑龙江汉族和新加坡华裔牙齿的釉柱横纹周期中位数均为7，但黑龙江汉族的釉柱横纹周期计数往往低于新加坡华裔（<0.01）。新加坡华裔女性和男性牙齿的釉柱横纹周期中位数之间未观察到显著的性别差异（=0.511）。我们得出结论，在种族和地理位置保持不变的情况下，釉柱横纹周期中位数在统计学上可能因地理位置而异，但不因性别而异。需要进一步研究来探讨地理位置之间釉柱横纹周期变化的原因，以及验证釉柱横纹周期的其他生物环境决定因素。
