Shekhar Abhinav, Rana Akshim, Srivastava Shitij, Bhatia Love K, Chaturvedi Anshuman, Singh Abhishek
Department of Prosthodontics, Sardar Patel Post Graduate Institute of Dental and Medical Sciences, Lucknow, IND.
Cureus. 2025 Jun 18;17(6):e86311. doi: 10.7759/cureus.86311. eCollection 2025 Jun.
Aim and objectives This study aimed to assess the influence of three fabrication techniques, computer-aided design (CAD) and computer-aided manufacturing (CAM) milling, three-dimensional (3D) printing, and conventional self-curing, on the fracture resistance of implant-supported polymethyl methacrylate (PMMA) resin-based provisional crowns. Methods An in vitro comparative study was conducted using 45 implant analogs with straight titanium abutments, equally distributed into three groups. Each analog was embedded vertically in custom acrylic resin blocks (20 × 20 × 20 mm). Abutments were torqued to 25 Ncm, and screw access channels were sealed with Teflon pellets and composite resin. Provisional crowns were fabricated using CAD-CAM milling, 3D printing, and conventional self-curing methods. All crowns were cemented and subjected to axial loading in a universal testing machine until fracture. Fracture resistance values were recorded and statistically analyzed. Results Crowns made with 3D printing showed the greatest average resistance to fracture, followed by CAD-CAM milling, and the crowns fabricated using the conventional self-curing method had the lowest fracture resistance. Statistical tests confirmed that these differences between the three groups were significant (p <0.05). The stronger performance of the 3D-printed crowns points to better overall durability, suggesting they could be especially useful for implant-supported provisional restorations in clinical practice. Conclusion Taking into account the limitations of this laboratory study, 3D-printed PMMA crowns showed the highest fracture resistance compared to the other fabrication methods tested. Crowns made by CAD-CAM milling also had strength levels that are acceptable for clinical use, making them a good alternative option. On the other hand, crowns produced with conventional self-curing methods were the least resistant to fracture, which means they might only be suitable for situations where the load is minimal. Ultimately, the choice of fabrication technique should be based on specific clinical requirements, material properties, and cost considerations.
目的和目标 本研究旨在评估三种制作技术，即计算机辅助设计（CAD）与计算机辅助制造（CAM）铣削、三维（3D）打印以及传统自凝技术，对种植体支持的聚甲基丙烯酸甲酯（PMMA）树脂基临时冠抗折性的影响。方法 采用45个带有直钛基台的种植体代型进行体外对比研究，将其平均分为三组。每个代型垂直嵌入定制的丙烯酸树脂块（20×20×20毫米）中。将基台扭矩至25 Ncm，并用聚四氟乙烯小球和复合树脂密封螺丝通道。采用CAD-CAM铣削、3D打印和传统自凝方法制作临时冠。所有冠均进行粘固，并在万能试验机上进行轴向加载直至折断。记录抗折性值并进行统计学分析。结果 3D打印制作的冠平均抗折性最强，其次是CAD-CAM铣削制作的冠，而采用传统自凝方法制作的冠抗折性最低。统计检验证实三组之间的这些差异具有显著性（p<0.05）。3D打印冠的更强性能表明其整体耐久性更好，这表明它们在临床实践中对种植体支持的临时修复可能特别有用。结论 考虑到本实验室研究的局限性，与其他测试的制作方法相比，3D打印的PMMA冠显示出最高的抗折性。CAD-CAM铣削制作的冠的强度水平在临床上也是可以接受的，使其成为一个不错的替代选择。另一方面，传统自凝方法制作的冠抗折性最差，这意味着它们可能仅适用于负荷最小的情况。最终，制作技术的选择应基于特定的临床要求、材料特性和成本考虑。
