Waly Ahmed S, Yousief Salah A, Moteea Mohamed Elsayed, Abu Samadah Mohammad Said, Elfezary Mohamed Taha
Department of Pediatric Dentistry, Faculty of Dentistry, Al-Azhar University, Assiut, Egypt.
Department of Restorative and Prosthetic Dental Sciences, College of Dentistry, Dar Al Uloom University, Riyadh, 13313, Saudi Arabia.
BMC Oral Health. 2025 Jun 21;25(1):954. doi: 10.1186/s12903-025-06339-x.
The objective of this study was to examine the impact of various types of cements on primary molar tooth restored with a Bioflx crown.
Three distinct finite element models were developed to represent three different cements; (1) conventional glass ionomer cement (GIC) (approximately 17 μm thick), (2) self-curing resin-modified GIC (RMGIC) (approximately 10 μm thick), and (3) self-cure resin cement (RC) (approximately 30 μm thick), all supporting/securing the Bioflx crown (approximately 330 microns thick). The geometry of the lower second primary molar was captured by laser scanning and then processed to create a solid model. This model was then imported into finite element software to assign materials, create a mesh, and evaluate stress and deformation under average normal occlusal loads. An applied load of 330 N was evaluated at three angles: vertical, oblique at 45°, and lateral.
The results indicated that model #2 (self-curing resin-modified GIC) exhibited the greatest deformation across all model components under the three loading conditions. The results for conventional GIC cement were comparable to those of self-cure resin cement. The resin-modified self-curing GIC (model #2) demonstrated high stress levels under lateral and oblique loads. Additionally, elevated stress concentrations were observed in the cortical bone region.
A cement type with a higher modulus of elasticity may be preferred over other types, in addition to the potential for use with a thinner thickness. Therefore, conventional GIC demonstrated the best performance among the cements evaluated in this study. This was followed by self-cure resin cement, while self-curing resin-modified GIC might be excluded due to expectation of failure.
本研究的目的是研究不同类型的粘结剂对用Bioflx冠修复的乳磨牙的影响。
建立了三个不同的有限元模型来代表三种不同的粘结剂；（1）传统玻璃离子水门汀（GIC）（约17μm厚），（2）自固化树脂改性GIC（RMGIC）（约10μm厚），以及（3）自固化树脂粘结剂（RC）（约30μm厚），所有这些都用于支持/固定Bioflx冠（约330微米厚）。通过激光扫描获取下颌第二乳磨牙的几何形状，然后进行处理以创建实体模型。然后将该模型导入有限元软件中，以指定材料、创建网格，并评估平均正常咬合负荷下的应力和变形。在三个角度评估330N的施加负荷：垂直、45°倾斜和侧向。
结果表明，模型#2（自固化树脂改性GIC）在三种加载条件下，所有模型组件的变形最大。传统GIC粘结剂的结果与自固化树脂粘结剂的结果相当。树脂改性自固化GIC（模型#2）在侧向和倾斜负荷下表现出高应力水平。此外，在皮质骨区域观察到应力集中升高。
除了可能使用更薄的厚度外，具有较高弹性模量的粘结剂类型可能比其他类型更受青睐。因此，在本研究评估的粘结剂中，传统GIC表现出最佳性能。其次是自固化树脂粘结剂，而自固化树脂改性GIC可能因预期会失效而被排除。
