Department of Civil and Environmental Engineering, Sejong University, Seoul, Korea.
Department of Prosthodontics, Dental College, Yonsei University, Seoul, Korea.
BMC Oral Health. 2022 Dec 1;22(1):550. doi: 10.1186/s12903-022-02596-2.
In clinical settings, tooth preparation for prefabricated zirconia crowns (PZCs) in the primary dentition varies widely. However, knowledge about the biomechanical behavior of PZCs in various clinical settings is limited. This study was conducted to evaluate the biomechanical behavior of PZCs in different clinical settings using 3-dimensional finite element analysis.
3-dimensional models of the PZC, cement, and tooth with six different conditions were simulated in primary molar teeth, incorporating cement thickness (100, 500, and 1000 μm) and cement type (resin-modified glass ionomer cement and resin cement). A total of 200 N of occlusal force was applied to the models, both vertically and obliquely as representative cases. A general linear model univariate analysis with partial eta-squared (ηp) was performed to evaluate the relative effects of the variables.
The overall stress of tooth was increased as the cement space increases under oblique loading. The von Mises stress values of the resin cements were significantly higher than those of the resin-modified glass ionomer cements for all cement thicknesses (p < .05). The effect size of the cement type (η = .519) was more dominant than the cement thickness (η = .132) in the cement layer.
Within the limits of this study, cement type has a greater influence on the biomechanical behavior of PZCs than cement thickness.
在临床环境中，预制氧化锆冠（PZC）在乳牙中的牙体预备差异很大。然而，对于不同临床环境下 PZC 的生物力学行为的了解有限。本研究采用三维有限元分析评估不同临床环境下 PZC 的生物力学行为。
模拟了 PZC、水泥和牙齿的三维模型，共有 6 种不同条件，纳入了水泥厚度（100、500 和 1000 μm）和水泥类型（树脂改性玻璃离子水泥和树脂水泥）。对模型施加 200 N 的垂直和斜向咬合力，作为代表性情况。采用具有偏 eta 平方（ηp）的单变量一般线性模型分析评估变量的相对影响。
斜向加载时，随着水泥空间的增加，牙体的整体应力增加。对于所有水泥厚度，树脂水泥的 von Mises 应力值均明显高于树脂改性玻璃离子水泥（p <.05）。水泥类型的效应大小（η=.519）比水泥厚度（η=.132）在水泥层中更具主导性。
在本研究范围内，水泥类型对 PZC 的生物力学行为的影响大于水泥厚度。
