Department of Conservative Dentistry, School of Dentistry, Pusan National University, Dental Research Institute, Yangsan, Korea.
PLoS One. 2020 Oct 28;15(10):e0240979. doi: 10.1371/journal.pone.0240979. eCollection 2020.
The purpose of this study was to analyze the relationship between the height and depth of buccal non-carious cervical lesions (NCCLs) and the relationship between the size of buccal NCCLs and clinical crown-root ratio of both buccal and lingual (palatal) sides using micro-computed tomography (micro-CT) images of the teeth and periodontal tissues from the cadavers. The micro-CT images of 56 teeth and their supporting tissues were obtained from 17 cadavers. From these images, the height and depth of NCCLs and the length of the buccal and lingual (palatal) clinical crowns were measured, and the conventional/modified clinical crown-root ratios were calculated. The height and depth ratio of NCCLs were analyzed statistically with the conventional/modified crown-root ratios by Pearson's correlation and multiple regression. According to the Pearson's correlation, the height and depth of buccal NCCLs were positively correlated with the modified buccal clinical crown-root ratio (p < 0.001 and p = 0.013, respectively). The regression model composed of variables of crown-root ratios explained the height of buccal NCCLs, and the prominent factor of the model was the modified buccal clinical crown-root ratio (p < 0.001). Moreover, the depth of buccal NCCLs was also explained by the regression model, and its prominent factor was the proportion of modified buccal and lingual (palatal) clinical crowns (p = 0.004). The buccal NCCLs were related to the crown-root ratios; particularly, the level of buccal gingival margin could be associated with the formation of buccal NCCLs.
本研究旨在通过对尸体牙齿及其牙周组织的 micro-CT 图像分析颊面非龋性颈缘缺损（NCCLs）的高度和深度与颊面 NCCLs 大小和颊面及（腭）舌面临床冠根比的关系。从 17 具尸体中获得了 56 颗牙齿及其支持组织的 micro-CT 图像。从这些图像中测量了 NCCLs 的高度和深度以及颊面和舌面（腭面）临床冠的长度，并计算了常规/改良的临床冠根比。通过 Pearson 相关分析和多元回归分析，对 NCCLs 的高度和深度比与常规/改良的冠根比进行了统计学分析。根据 Pearson 相关分析，颊面 NCCLs 的高度和深度与改良颊面临床冠根比呈正相关（p<0.001 和 p=0.013）。由冠根比变量组成的回归模型解释了颊面 NCCLs 的高度，该模型的突出因素是改良颊面临床冠根比（p<0.001）。此外，颊面 NCCLs 的深度也可以用回归模型来解释，其突出因素是改良颊面和舌面（腭面）临床冠的比例（p=0.004）。颊面 NCCLs 与冠根比有关；特别是，颊侧龈缘的水平可能与颊面 NCCLs 的形成有关。
