Lawson Nathaniel C, Brown Pierpont, Hamdan Suleiman, Alford Aaron, Nejat Amir H
Associate Professor, Department of Clinical and Community Sciences, The University of Alabama at Birmingham School of Dentistry, Birmingham, Ala.
Resident, Department of Orthodontics, The University of Alabama at Birmingham School of Dentistry, Birmingham, Ala.
J Prosthet Dent. 2025 Feb;133(2):576.e1-576.e6. doi: 10.1016/j.prosdent.2024.10.021. Epub 2024 Nov 12.
Three-dimensional (3D) printing offers an efficient method of producing occlusal devices; however, their wear resistance is poorly understood.
The purpose of this in vitro study was to compare the wear resistance of flexible and rigid 3D printed occlusal device materials with milled and conventionally processed occlusal device materials.
Blocks (n=8) of 3 flexible 3D printed materials (KeySplint Soft, NightGuard Flex 2, SmileGuard), 2 rigid 3D printed materials (KeySplint Hard, NightGuard Firm 2), 1 milled material (Ceramill A-Splint), 1 thermoform material (Erkoloc-Pro), 1 light-polymerized material (Eclipse Prosthetic Resin), 1 heat-polymerized material (Excel Formula Heat Cure Denture Base Material), and 1 autopolymerized material (Great Lakes Splint Resin Acrylic) were prepared and wet polished with 1200-grit SiC paper. The specimens were placed in a modified Alabama wear testing device with spherical zirconia antagonists. The devices applied a 20-N load and 2-mm horizontal slide for 400 000 cycles, and the test was run in a 33% glycerin solution. Following the wear test, the volumetric wear was measured with an optical profilometer. The Vickers microhardness of the materials was also measured (n=3). Volumetric wear and microhardness were compared with 1-way ANOVAs and Tukey post hoc analyses (α=.05).
Significant differences were found between the wear of the different occlusal device materials (P<.001). The rigid 3D printed materials experienced similar wear as the light-polymerized, heat-polymerized, and milled occlusal device materials. The autopolymerized and thermoformed occlusal device material experienced significantly more wear (P<.05). The flexible 3D printed materials had the significantly greatest wear (P<.05). A statistically significant, strong negative correlation between hardness and volumetric wear was found (r=-.93; P<.001).
Rigid 3D printed occlusal device materials exhibit a high degree of wear resistance; however, flexible 3D printed occlusal device materials exhibit relatively low wear resistance.
三维（3D）打印提供了一种生产咬合装置的有效方法；然而，人们对其耐磨性了解甚少。
本体外研究的目的是比较柔性和刚性3D打印咬合装置材料与铣削和传统加工的咬合装置材料的耐磨性。
制备8个试件块，分别为3种柔性3D打印材料（KeySplint Soft、NightGuard Flex 2、SmileGuard）、2种刚性3D打印材料（KeySplint Hard、NightGuard Firm 2）、1种铣削材料（Ceramill A-Splint）、1种热成型材料（Erkoloc-Pro）、1种光聚合材料（Eclipse Prosthetic Resin）、1种热聚合材料（Excel Formula Heat Cure Denture Base Material）和1种自聚合材料（Great Lakes Splint Resin Acrylic），并用1200目碳化硅砂纸进行湿抛光。将试件置于带有球形氧化锆对磨体的改良阿拉巴马磨损测试装置中。该装置施加20 N的载荷和2 mm的水平滑动，进行400 000次循环，测试在33%的甘油溶液中进行。磨损测试后，用光学轮廓仪测量体积磨损。还测量了材料的维氏显微硬度（n = 3）。采用单因素方差分析和Tukey事后分析（α = 0.05）比较体积磨损和显微硬度。
不同咬合装置材料的磨损之间存在显著差异（P < 0.001）。刚性3D打印材料的磨损与光聚合、热聚合和铣削的咬合装置材料相似。自聚合和热成型的咬合装置材料磨损明显更多（P < 0.05）。柔性3D打印材料的磨损最大（P < 0.05）。硬度与体积磨损之间存在统计学上显著的强负相关（r = -0.93；P < 0.001）。
刚性3D打印咬合装置材料具有高度的耐磨性；然而，柔性3D打印咬合装置材料的耐磨性相对较低。
