Department of Prosthodontics, Faculty of Dentistry, Lokman Hekim University, Söğütözü. 2179 St., Çankaya, 06510, Ankara, Turkey.
Department of Physics, Eskisehir Osmangazi University, Eskisehir, Turkey.
Odontology. 2024 Jul;112(3):782-797. doi: 10.1007/s10266-023-00881-2. Epub 2023 Dec 29.
There is limited information on the repairability of prostheses produced with digital technology. This study aims to evaluate various surface treatments on flexural bond strength of repaired dentured base resins produced by digital and conventional methods. A total of 360 samples were prepared from one heat-polymerized, one CAD/CAM milled and one 3D printed denture base materials. All of the test samples were subjected to thermocycling (5-55 °C, 5000 cycles) before and after repair with auto-polymerizing acrylic resin. The test samples were divided into five subgroups according to the surface treatment: grinding with silicon carbide (SC), sandblasting with AlO (SB), Er:YAG laser (L), plasma (P) and negative control (NC) group (no treatment). In addition, the positive control (PC) group consisted of intact samples for the flexural strength test. Surface roughness measurements were performed with a profilometer. After repairing the test samples, a universal test device determined the flexural strength values. Both the surface topography and the fractured surfaces of samples were examined by SEM analysis. The elemental composition of the tested samples was analyzed by EDS. Kruskal-Wallis and Mann-Whitney U tests were performed for statistical analysis of data. SB and L surface treatments statistically significantly increased the surface roughness values of all three materials compared to NC subgroups (p < 0.001). The flexural strength values of the PC groups in all three test materials were significantly higher than those of the other groups (p < 0.001). The repair flexural strength values were statistically different between the SC-SB, L-SB, and NC-SB subgroups for the CAD/CAM groups, and the L-SC and L-NC subgroups for the 3D groups (p < 0.001). The surface treatments applied to the CAD/CAM and heat-polymerized groups did not result in a statistically significant difference in the repair flexural strength values compared to the NC groups (p > 0.05). Laser surface treatment has been the most powerful repair method for 3D printing technique. Surface treatments led to similar repair flexural strengths to untreated groups for CAD/CAM milled and heat-polymerized test samples.
关于使用数字技术生产的假体的可修复性的信息有限。本研究旨在评估数字和传统方法生产的义齿基托树脂修复后的弯曲结合强度的各种表面处理。总共从一种热聚合、一种 CAD/CAM 铣削和一种 3D 打印义齿基托材料中制备了 360 个样本。所有测试样本在修复前和修复后都经过热循环（5-55°C，5000 次循环），使用自聚合丙烯酸树脂进行修复。根据表面处理，将测试样本分为五组：碳化硅磨料（SC）、氧化铝喷砂（SB）、铒：钇铝石榴石激光（L）、等离子体（P）和阴性对照（NC）组（无处理）。此外，阳性对照（PC）组由用于弯曲强度测试的完整样本组成。使用轮廓仪进行表面粗糙度测量。修复测试样本后，万能试验机确定弯曲强度值。通过 SEM 分析检查样品的表面形貌和断裂面。通过 EDS 分析测试样品的元素组成。对数据进行 Kruskal-Wallis 和 Mann-Whitney U 检验。与 NC 亚组相比，SB 和 L 表面处理使所有三种材料的表面粗糙度值均显著增加（p<0.001）。所有三种测试材料的 PC 组的弯曲强度值均显著高于其他组（p<0.001）。在 CAD/CAM 组中，SC-SB、L-SB 和 NC-SB 亚组之间的修复弯曲强度值存在统计学差异，在 3D 组中，L-SC 和 L-NC 亚组之间也存在统计学差异（p<0.001）。与 NC 组相比，CAD/CAM 和热聚合组的表面处理并未导致修复弯曲强度值有统计学差异（p>0.05）。激光表面处理是 3D 打印技术最有效的修复方法。对于 CAD/CAM 铣削和热聚合测试样本，表面处理导致修复弯曲强度与未处理组相似。
