Nanfang Hospital, Southern Medical University, Guangzhou, China.
Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering, Guangzhou, China.
J Dent Res. 2022 Jul;101(8):912-920. doi: 10.1177/00220345221074909. Epub 2022 Feb 21.
Use of high-performance fibers such as poly(p-phenylene-2,6-benzobisoxazole) (PBO) improves the mechanical properties of dental fiber-reinforced composites (FRCs). However, the surfaces of high-performance fibers are relatively inert, and the interface with the resin matrix is poor. This has become a limitation restricting the performance of PBO FRCs in dentistry. Nanomaterials were introduced onto PBO fibers to construct various hierarchical reinforcements to obtain a dental FRC with higher flexural performance and optimized interface bonding. Four hierarchical reinforcements were constructed: PBO-ZnO nanoparticles (NPs), PBO-ZnO nanowires (NWs), PBO-ZnO NPs-cage silsesquioxane (POSS), and PBO-ZnO NWs-POSS. Performance following this optimized method was evaluated at macroscale and microscale levels, including measurement of the interfacial properties and mechanical properties of FRCs. The physicochemical characteristics of PBO fibers before and after modification were measured to determine the interfacial bonding mechanisms and to verify the connection between the microinterface and macromechanical properties. The cytotoxicity of the preferred PBO FRC was evaluated using the CCK8 assay. In comparison to other designs, the interfacial shear strength (IFSS) of PBO-ZnO NWs-POSS was the highest (29.31 ± 2.40 MPa). The corresponding FRC had the highest flexural strength under a static load (925.0 ± 39.2 MPa), the flexural modulus (39.39 ± 1.41 GPa) was equivalent to that of human dentin, and in vitro cytotoxicity was acceptable. The interfacial bonding mechanisms of PBO-ZnO NWs-POSS resulted from mechanical interlocking, chemical bonds, hydrogen bonds, and van der Waals forces. In summary, the PBO-ZnO NWs-POSS hierarchical reinforcement was introduced in dental FRCs and showed remarkable enhancement of the IFSS and flexural properties. We verified that the PBO-ZnO NWs-POSS hierarchical reinforcement was successful. This PBO FRC may be applied in dentistry as a new option for endodontic posts. Our study provides an interface design strategy for developing high-performance FRCs reinforced with high-performance fibers for dental applications.
使用高性能纤维（如聚对苯撑苯并二恶唑（PBO））可以提高牙科纤维增强复合材料（FRC）的机械性能。然而，高性能纤维的表面相对惰性，与树脂基体的界面较差。这已成为限制 PBO FRC 在牙科应用中性能的一个因素。将纳米材料引入 PBO 纤维中，构建各种层次的增强体，以获得具有更高弯曲性能和优化界面结合的牙科 FRC。构建了四种层次增强体：PBO-ZnO 纳米颗粒（NPs）、PBO-ZnO 纳米线（NWs）、PBO-ZnO NPs-笼状倍半硅氧烷（POSS）和 PBO-ZnO NWs-POSS。通过宏观和微观水平评估这种优化方法的性能，包括测量 FRC 的界面性能和机械性能。测量改性前后 PBO 纤维的物理化学特性，以确定界面结合机制，并验证微界面和宏观力学性能之间的关系。使用 CCK8 测定法评估首选 PBO FRC 的细胞毒性。与其他设计相比，PBO-ZnO NWs-POSS 的界面剪切强度（IFSS）最高（29.31 ± 2.40 MPa）。相应的 FRC 在静态载荷下具有最高的弯曲强度（925.0 ± 39.2 MPa），弯曲模量（39.39 ± 1.41 GPa）与人类牙本质相当，体外细胞毒性可接受。PBO-ZnO NWs-POSS 的界面结合机制源于机械联锁、化学键、氢键和范德华力。总之，将 PBO-ZnO NWs-POSS 层次增强体引入牙科 FRC 中，显著提高了 IFSS 和弯曲性能。我们验证了 PBO-ZnO NWs-POSS 层次增强体的成功。这种 PBO FRC 可能在牙科中作为根管桩的新选择得到应用。我们的研究为开发用于牙科应用的高性能纤维增强高性能 FRC 提供了一种界面设计策略。
