权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

A three-dimensional analysis of enamel thickness and enamel-dentine junction form in permanent human teeth

人类恒牙牙釉质厚度和牙釉质-牙本质连接形态的三维分析

基本信息

批准号：
14540657
负责人：
SUWA Gen
金额：
$ 2.24万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14540657/
关键词：
human permanent teeth enamel thickness enamel-dentine junction micro-CT エナメル質厚さ

项目摘要

In the present study, 318 permanent human tooth crowns were micro-CT scanned and thigh resolution volume data sets obtained. Data analysis focussed primarily on enamel thickness measurements taken in the mesial cusp section of 167 unworn molars. We obtained the following results. Enamel thickness at the cusp tips and occlusal basin in sections slightly offset from the mesial cusp section was found to be inaccurate by up to about 0.5 to 1 mm. We also found that maximum 'radial' thickness of the lateral crown face was least affected by section position, usually with discrepancies of less than about 0.1-0.2 mm. Mid-lateral crown thickness was found to vary by definition of the horizontal reference plane, and thus less useful in evaluating enamel distribution patterns than maximum lateral thickness. In all serial positions in both upper and lower molars, a 'functional' to 'non-functional' side gradient in enamel thickness was observed in cusp tip, occlusal basin, and lateral crown face enamel, with the exception of the characteristically thin enamel at the protoconid and paracone cusp tips. Serial differences in thickness were seen between the thinner M1 and the two posterior molars in many but not all measures of thickness, the pattern of which appears to be influenced by the thin M1 mesiobuccal cusp enamel. Individual variation of maximum lateral thickness, the least variable measure of thickness, was found to be substantial even with serial and buccolingual positions controlled. Correlation between whole crown average enamel thickness and maximum lateral thickness was high, indicating that the latter is a potentially useful predictor of overall enamel thickness of the molar crown.

在本研究中，对318个恒牙冠进行了微ct扫描，获得了大腿分辨率体积数据集。数据分析主要集中在167颗未磨损磨牙中尖段的牙釉质厚度测量上。我们得到了以下结果。牙尖尖尖部和咬合盆部的牙釉质厚度与牙尖中缘部分相差0.5 ~ 1mm。我们还发现，侧冠面最大“径向”厚度受断面位置的影响最小，通常误差小于0.1-0.2 mm。研究发现，中侧冠厚度随水平参考平面的定义而变化，因此在评估牙釉质分布模式方面不如最大侧冠厚度有用。在上下磨牙的所有连续位置上，除原锥体和副锥体尖尖的典型薄牙釉质外，在尖尖、咬合盆和侧冠面牙釉质上观察到“功能”到“非功能”的牙釉质厚度梯度。在许多但不是所有的厚度测量中，薄的M1和两颗后磨牙之间的厚度存在一系列差异，其模式似乎受到薄的M1中颊尖牙釉质的影响。最大侧面厚度的个体差异，最小的厚度测量变量，被发现是实质性的，即使串行和颊舌位置控制。全冠平均牙釉质厚度与最大侧壁厚度之间的相关性很高，表明后者是臼齿冠整体牙釉质厚度的潜在有用预测指标。