Department of Restorative Dentistry, Faculty of Dental Medicine, Umm Al-Qura University.
Dent Mater J. 2024 Sep 28;43(5):693-700. doi: 10.4012/dmj.2024-018. Epub 2024 Jul 31.
This study evaluated fracture resistance of monolithic fixed dental prostheses (FDPs) fabricated using different placement strategies of various connector designs in multilayered zirconia disc. Monolithic FDPs were placed in translucent and dentin layers of multilayered zirconia disc and fabricated with V-shaped and U-shaped connector designs gained by sharp and blunt millings. The FDPs were cemented on abutment models made of polymer material, underwent thermal cycles, and loaded to fracture using the universal testing machine. Fracture loads and modes were analyzed using two-way ANOVA, Tukey's post hoc test, and Fisher exact test (p≤0.05). The chosen placement strategy and connector designs gained by different milling procedures in computer-aided design/computer-aided manufacturing technology affect fracture resistance of monolithic FDPs made of multilayered zirconia materials. Placing the connector in translucent layer rather than dentin layer of multilayered zirconia disc and using sharp milling significantly reduces fracture resistance of monolithic multilayered zirconia FDPs.
本研究评估了不同连接设计的各种放置策略在多层氧化锆盘中制造的整体式固定义齿（FDP）的抗断裂能力。整体式 FDP 被放置在多层氧化锆盘中的半透明层和牙本质层中，并使用锐利和钝磨获得的 V 形和 U 形连接设计制造。FDP 被粘接到由聚合物材料制成的基牙模型上，经历热循环，并使用万能试验机加载至断裂。使用双向方差分析、Tukey 事后检验和 Fisher 确切检验（p≤0.05）分析断裂载荷和模式。在计算机辅助设计/计算机辅助制造技术中选择的放置策略和连接器设计通过不同的铣削程序影响由多层氧化锆材料制成的整体式 FDP 的抗断裂能力。将连接器放置在多层氧化锆盘中的半透明层而不是牙本质层中，并使用锐磨，显著降低了整体式多层氧化锆 FDP 的抗断裂能力。
