de Sousa Thiago Carvalho, Ramos Alexia Guimarães, Garcia Fernanda Cristina Pimentel, de Medeiros Rodrigo Antonio
Clinical instructor, Department of Biologic and Material Sciences & Prosthodontics, University of Michigan School of Dentistry, Ann Arbor, MI.
Postgraduate student, University of Brasilia (UnB), Brasilia, Federal District, Brazil.
J Prosthet Dent. 2025 Feb;133(2):596.e1-596.e9. doi: 10.1016/j.prosdent.2024.10.010. Epub 2024 Nov 1.
With advancements in digital technologies, the digital workflow has revolutionized the fabrication of occlusal devices through additive methods using 3-dimensional (3D) printing. However, an established protocol for polishing 3D printed occlusal devices is lacking, despite this step being crucial for minimizing surface porosity, material fatigue and preventing bacterial plaque accumulation, thereby contributing to device longevity.
The purpose of this in vitro study was to evaluate the impact of polishing systems on the surface roughness and Vickers microhardness of heat-polymerizing acrylic resin and 3D printing resins used for occlusal devices.
One hundred and twenty microwaved-polymerized acrylic resin and 3D printed resin specimens (40×40×3 mm) were divided into 12 groups (n=10) based on the type of resin and polishing protocol (Sealant, DhPro, Dhpro + Sealant, Trihawk, Trihawk + Sealant, and control). Surface roughness (Ra) and Vickers microhardness were tested. Additionally, 1 specimen per group underwent scanning electron microscopy before and after thermocycling (5000 cycles, 5 ºC and 55 ºC). Data analysis involved a 2-way ANOVA, 2-way repeated measured ANOVA, and the Tukey multiple comparison test (α=.05).
The Trihawk polishing protocol yielded significantly higher microhardness and lower surface roughness values for both resins. After thermocycling, the acrylic resin maintained its surface roughness for the Trihawk, Trihawk + Sealant, and unpolished groups, but all groups showed decreased microhardness. The 3D printing resin exhibited increased surface roughness and reduced microhardness after thermocycling across all groups.
The polishing protocol affects the surface microhardness and roughness of 3D printing resins and microwave acrylic resins for occlusal devices. Polishing using the Trihawk polishing protocol demonstrated significantly smoother and harder surfaces for both resins tested.
随着数字技术的进步，数字工作流程通过使用三维（3D）打印的增材方法彻底改变了咬合装置的制造。然而，尽管这一步骤对于最小化表面孔隙率、材料疲劳和防止细菌菌斑积聚从而延长装置寿命至关重要，但目前仍缺乏用于抛光3D打印咬合装置的既定方案。
本体外研究的目的是评估抛光系统对用于咬合装置的热聚合丙烯酸树脂和3D打印树脂的表面粗糙度和维氏显微硬度的影响。
将120个微波聚合丙烯酸树脂和3D打印树脂标本（40×40×3mm）根据树脂类型和抛光方案（密封剂、DhPro、Dhpro+密封剂、Trihawk、Trihawk+密封剂和对照组）分为12组（n=10）。测试表面粗糙度（Ra）和维氏显微硬度。此外，每组1个标本在热循环（5000次循环，5℃和55℃）前后进行扫描电子显微镜检查。数据分析采用双向方差分析、双向重复测量方差分析和Tukey多重比较检验（α=0.05）。
对于两种树脂，Trihawk抛光方案产生的显微硬度显著更高，表面粗糙度值更低。热循环后，丙烯酸树脂在Trihawk、Trihawk+密封剂和未抛光组中保持其表面粗糙度，但所有组的显微硬度均降低。所有组的3D打印树脂在热循环后表面粗糙度增加，显微硬度降低。
抛光方案影响用于咬合装置的3D打印树脂和微波丙烯酸树脂的表面显微硬度和粗糙度。使用Trihawk抛光方案进行抛光显示，所测试的两种树脂的表面明显更光滑、更坚硬。
