Topdağı Başak
Department of Prosthodontics, Faculty of Dentistry, Hamidiye Campus, University of Health Sciences, Istanbul 34668, Türkiye.
Polymers (Basel). 2025 May 27;17(11):1488. doi: 10.3390/polym17111488.
This study aimed to comparatively evaluate the effects of various surface treatment protocols on the shear bond strength (SBS) between heat-polymerized polymethyl methacrylate (PMMA) and different CAD/CAM framework materials, including cobalt-chromium (Co-Cr) alloys, ceramic particle-reinforced polyetheretherketone (PEEK), and glass fiber-reinforced composite resin (FRC). A total of 135 disc-shaped specimens were prepared from Co-Cr, PEEK, and FRC materials. Surface treatments specific to each material, including airborne-particle abrasion, sulfuric acid etching, laser irradiation, plasma activation, and primer application, were applied. PMMA cylinders were polymerized onto the treated surfaces, and all specimens were subjected to 30,000 thermal cycles. SBS values were measured using a universal testing machine, and the failure modes were classified. The normality of data distribution was assessed using the Kolmogorov-Smirnov test, and the homogeneity of variances was evaluated using Levene's test. Group comparisons were performed using the Kruskal-Wallis test, and Dunn's post hoc test with Bonferroni correction was applied in cases where significant differences were detected (α = 0.05). The highest SBS values (27-28 MPa) were obtained in the Co-Cr group and in the PEEK groups treated with sulfuric acid and primer. In contrast, the PEEK group with additional laser treatment exhibited a lower SBS value. The untreated PEEK group showed significantly lower SBS (3.9 MPa) compared to all other groups. The Trinia groups demonstrated intermediate SBS values (16.5-17.4 MPa), which exceeded the clinically acceptable threshold of 10 MPa. SEM observations revealed material- and protocol-specific surface responses; plasma-treated specimens maintained topographic integrity, whereas laser-induced surfaces showed localized degradation, particularly following dual-step protocols. Fracture mode analysis indicated that higher SBS values were associated with cohesive or mixed failures. SEM observations suggested that plasma treatment preserved surface morphology more effectively than laser treatment. This study highlights the importance of selecting material-specific surface treatments to optimize bonding between CAD/CAM frameworks and PMMA. Sulfuric acid and primer provided strong adhesion for PEEK, while the addition of laser or plasma offered no further benefit, making such steps potentially unnecessary. Trinia frameworks also showed acceptable performance with conventional treatments. These findings reinforce that simplified conditioning protocols may be clinically sufficient, and indicate that FRC materials like Trinia should be more fully considered for their broader clinical potential in modern CAD/CAM-based prosthetic planning.
本研究旨在比较评估各种表面处理方案对热聚合聚甲基丙烯酸甲酯（PMMA）与不同CAD/CAM框架材料之间剪切粘结强度（SBS）的影响，这些材料包括钴铬（Co-Cr）合金、陶瓷颗粒增强聚醚醚酮（PEEK）和玻璃纤维增强复合树脂（FRC）。从Co-Cr、PEEK和FRC材料制备了总共135个圆盘形试样。对每种材料进行了特定的表面处理，包括空气颗粒研磨、硫酸蚀刻、激光照射、等离子体活化和底漆应用。将PMMA圆柱体聚合到处理过的表面上，所有试样都经受30000次热循环。使用万能试验机测量SBS值，并对失效模式进行分类。使用Kolmogorov-Smirnov检验评估数据分布的正态性，使用Levene检验评估方差的齐性。使用Kruskal-Wallis检验进行组间比较，在检测到显著差异的情况下应用经Bonferroni校正的Dunn事后检验（α = 0.05）。在Co-Cr组以及用硫酸和底漆处理的PEEK组中获得了最高的SBS值（约27 - 28 MPa）。相比之下，额外进行激光处理的PEEK组的SBS值较低。未处理的PEEK组与所有其他组相比，SBS值显著较低（约3.9 MPa）。Trinia组的SBS值处于中等水平（16.5 - 17.4 MPa），超过了临床上可接受的10 MPa阈值。扫描电子显微镜（SEM）观察揭示了材料和方案特定的表面反应；等离子体处理的试样保持了形貌完整性，而激光处理的表面显示出局部降解，特别是在两步处理方案之后。断裂模式分析表明，较高的SBS值与内聚或混合失效相关。SEM观察表明，等离子体处理比激光处理更有效地保留了表面形态。本研究强调了选择材料特定表面处理以优化CAD/CAM框架与PMMA之间粘结的重要性。硫酸和底漆为PEEK提供了强附着力，而添加激光或等离子体并没有进一步的益处，使得这些步骤可能不必要。Trinia框架在传统处理下也表现出可接受的性能。这些发现强化了简化的预处理方案在临床上可能就足够了这一观点，并表明像Trinia这样的FRC材料在现代基于CAD/CAM的修复计划中因其更广泛的临床潜力应得到更充分的考虑。
