Abad-Coronel Cristian, Bravo Manuel, Tello Salomé, Cornejo Emilia, Paredes Yirelly, Paltan Cesar A, Fajardo Jorge I
CAD/CAM Materials and Digital Dentistry Research Group, Faculty of Dentistry, Universidad de Cuenca, Cuenca 010105, Ecuador.
Faculty of Dentistry, University of Cuenca, Cuenca 010105, Ecuador.
Polymers (Basel). 2023 Sep 15;15(18):3773. doi: 10.3390/polym15183773.
The aim of this study was to evaluate and compare the fracture resistance of a single-unit fixed prosthesis, using a CAD/CAM PMMA material and two printed materials (3DPPa and 3DPPb). A typodont with a specific preparation for a full crown was used; a digital impression was made with a state-of-the-art scanner (PrimeScan, Dentsply-Sirona, New York, NY, USA), and a full coverage restoration was designed using a biogeneric design proposal by means of specific software (InLAB 22.1, Dentsply-Sirona, NY, USA). Sixty crowns were prepared, divided into three groups according to the material: 3DPPa ( = 20), 3DPPb ( = 20), both 3D-printed from the .STL file with a resolution of 50 μm, and PMMA ( = 20) milled-derived, which were subjected to a thermocycling process. A universal testing machine (Universal/Tensile Testing Machine, Autograph AGS-X Series) with integrated software (TRAPEZIUM LITE X) equipped with a 20 kN load cell was used to determine the fracture resistance. Significant differences were found by Kruskal-Wallis test and multiple comparisons ( < 0.05) in fracture resistance between materials. The fracture resistance for the PMMA material was higher, and the standard deviation was lower (x = 1427.9; sd = 36.9 N) compared to the 3DPPa (x = 1231; sd = 380.1 N) and 3DPPb (x = 1029.9; sd = 166.46 N) prints. The restorations from the milled-derived group showed higher average fracture resistance than the provisional restorations obtained from the printed groups. However, the results demonstrated that all three materials analyzed in single-unit restorations are capable of withstanding the average masticatory forces.
本研究的目的是评估和比较使用CAD/CAM聚甲基丙烯酸甲酯（PMMA）材料以及两种打印材料（3DPPa和3DPPb）的单单位固定修复体的抗折强度。使用了一个具有全冠特定预备的牙模型；通过一台先进的扫描仪（PrimeScan，登士柏西诺德，美国纽约州纽约市）进行数字印模，并借助特定软件（InLAB 22.1，登士柏西诺德，纽约州纽约市）采用生物通用设计方案设计全冠修复体。制备了60个全冠，根据材料分为三组：3DPPa（n = 20）、3DPPb（n = 20），二者均从分辨率为50μm的.STL文件进行3D打印，以及PMMA（n = 20），通过铣削加工获得，对这些全冠进行热循环处理。使用一台配备20kN测力传感器和集成软件（TRAPEZIUM LITE X）的万能试验机（万能/拉伸试验机，Autograph AGS-X系列）来测定抗折强度。通过Kruskal-Wallis检验和多重比较发现，材料之间的抗折强度存在显著差异（P < 0.05）。与3DPPa（x = 1231；sd = 380.1N）和3DPPb（x = 1029.9；sd = 166.46N）打印件相比，PMMA材料的抗折强度更高，标准差更低（x = 1427.9；sd = 36.9N）。铣削加工组的修复体显示出比打印组获得的临时修复体更高的平均抗折强度。然而，结果表明，在单单位修复体中分析的所有三种材料都能够承受平均咀嚼力。
