Post-Graduate Program in Oral Science, Faculty of Dentistry, Center for Development of Advanced Materials, Federal University of Santa Maria (UFSM), Santa Maria, Rio Grande do Sul State, Brazil.
Post-Graduate Program in Dentistry, Faculty of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil.
J Mech Behav Biomed Mater. 2024 Jul;155:106556. doi: 10.1016/j.jmbbm.2024.106556. Epub 2024 Apr 18.
This study assessed the mechanical properties and surface characteristics of dental prosthetic acrylic resin fabricated by 3D printing, comparing it with subtractive, pressing, and molding techniques. Bar-shaped specimens (N= 90; 65 × 10 × 3.3 mm; ISO:207951) were prepared and assigned into six groups: PRINT (3D printing vis stereolithography with PriZma 3D Bio Denture, Makertech Labs); SUB (subtractive manufacturing with Vipiblock Trilux, Vipi); PRESS Base (pressing using muffle with Thermo Vipi Wave, Vipi for base); PRESS Tooth (pressing with Onda-cryl, Clássico for tooth); MOLD Base (molding using addition silicone with Vipi Flash, Vipi for base); and MOLD Tooth (molding with Dencor, Clássico for tooth). Monotonic flexural strength (FS) and elastic modulus (E) were measured using a three-point bending approach (n= 5) on a universal testing machine at a crosshead speed of 5 mm/min. Fatigue testing (n= 10) followed similar geometry and settings, with a frequency of 2 Hz, initial stress level at 20 MPa, and stress increments of 5 MPa every 2,500 cycles. Surface roughness (n= 10) was assessed through profilometry, and fractographic and topographic analyses were conducted. Statistical analyses included One-Way ANOVA for monotonic FS, roughness, and E, along with Kaplan-Meier with Mantel-Cox post-hoc and Weibull analysis for fatigue strength. PRINT showed lower monotonic FS than the SUB and PRESS Tooth but comparable fatigue strength to these groups and superior to PRESS Base and MOLD (Base and Tooth) groups. All groups had similar Weibull moduli. Surface roughness of the PRINT group was comparable to most techniques but higher than the PRESS Tooth group. Fractographic analysis revealed fractures originating from surface defects under tensile stress, with SEM showing scratch patterns in all groups except PRINT, which had a more uniform surface. Despite its lower monotonic strength, 3D printed resin demonstrated comparable fatigue strength to subtractive and pressing methods and similar surface roughness to most methods, indicating its potential as a viable option for dental prosthesis.
本研究评估了通过 3D 打印制造的牙科修复用丙烯酸树脂的机械性能和表面特性，并与减法制造、压制和注塑成型技术进行了比较。制备了棒状试件（N=90；65×10×3.3mm；ISO：207951），并将其分为六组：PRINT（使用 PriZma 3D Bio Denture、Makertech Labs 的立体光固化 3D 打印）；SUB（使用 Vipiblock Trilux、Vipi 的减法制造）；PRESS Base（使用 Thermo Vipi Wave、Vipi 进行模压的底座）；PRESS Tooth（使用 Onda-cryl、Clássico 进行模压的牙齿）；MOLD Base（使用 Vipi Flash、Vipi 进行加成硅橡胶注塑的底座）；MOLD Tooth（使用 Dencor、Clássico 进行注塑的牙齿）。使用万能试验机以 5mm/min 的十字头速度进行三点弯曲法（n=5）测量单调弯曲强度（FS）和弹性模量（E）。疲劳试验（n=10）采用类似的几何形状和设置，频率为 2Hz，初始应力水平为 20MPa，每 2500 个循环增加 5MPa。使用轮廓仪评估表面粗糙度（n=10），并进行断口和形貌分析。统计分析包括单向方差分析（One-Way ANOVA）用于单调 FS、粗糙度和 E，以及用于疲劳强度的 Kaplan-Meier 与 Mantel-Cox 事后检验和威布尔分析。PRINT 的单调 FS 低于 SUB 和 PRESS Tooth，但疲劳强度与这些组相当，优于 PRESS Base 和 MOLD（Base 和 Tooth）组。所有组的威布尔模量都相似。PRINT 组的表面粗糙度与大多数技术相当，但高于 PRESS Tooth 组。断口分析显示，在拉伸应力下，起始于表面缺陷的断裂，SEM 显示除 PRINT 外所有组都有划痕模式，而 PRINT 的表面更均匀。尽管 3D 打印树脂的单调强度较低，但与减法制造和压制方法相比，其疲劳强度相当，与大多数方法的表面粗糙度相似，表明其作为牙科修复体的一种可行选择具有潜力。
