Hamanaka Ippei, Iwamoto Misa, Lassila Lippo Vj, Vallittu Pekka K, Shimizu Hiroshi, Takahashi Yutaka
a 1 Division of Removable Prosthodontics, Fukuoka Dental College , Fukuoka, Japan.
b 2 Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku , Turku, Finland.
Acta Odontol Scand. 2016;74(1):67-72. doi: 10.3109/00016357.2015.1042039. Epub 2015 May 8.
The aim of this study was to evaluate the effect of cycling deflection on the flexural behavior of injection-molded thermoplastic resins.
Six injection-molded thermoplastic resins (two polyamides, two polyesters, one polycarbonate, one polymethyl methacrylate) and, as a control, a conventional heat-polymerized denture based polymer of polymethyl methacrylate (PMMA) were used in this study. The cyclic constant magnitude (1.0 mm) of 5000 cycles was applied using a universal testing machine to demonstrate plasticization of the polymer. Loading was carried out in water at 23ºC with eight specimens per group (n = 8). Cycling load (N) and deformation (mm) were measured.
Force required to deflect the specimens during the first loading cycle and final loading cycle was statistically significantly different (p < 0.05) with one polyamide based polymer (Valplast) and PMMA based polymers (Acrytone and Acron). The other polyamide based polymer (LucitoneFRS), polyester based polymers (EstheShot and EstheShotBright) and polycarbonate based polymer (ReigningN) did not show significant differences (p > 0.05). None of the materials fractured during the loading test. One polyamide based polymer (Valplast) displayed the highest deformation and PMMA based polymers (Acrytone and Acron) exhibited the second highest deformation among the denture base materials.
It can be concluded that there were considerable differences in the flexural behavior of denture base polymers. This may contribute to the fatigue resistance of the materials.
本研究旨在评估循环挠曲对注塑热塑性树脂弯曲性能的影响。
本研究使用了六种注塑热塑性树脂（两种聚酰胺、两种聚酯、一种聚碳酸酯、一种聚甲基丙烯酸甲酯），并作为对照，使用了一种传统的热聚合聚甲基丙烯酸甲酯（PMMA）义齿基托聚合物。使用万能试验机施加5000次循环的恒定幅值（1.0毫米），以证明聚合物的塑化。在23℃的水中进行加载，每组八个试样（n = 8）。测量循环载荷（N）和变形（毫米）。
在第一次加载循环和最终加载循环期间使试样挠曲所需的力，对于一种聚酰胺基聚合物（Valplast）和PMMA基聚合物（Acrytone和Acron），在统计学上有显著差异（p < 0.05）。其他聚酰胺基聚合物（LucitoneFRS）、聚酯基聚合物（EstheShot和EstheShotBright）和聚碳酸酯基聚合物（ReigningN）没有显示出显著差异（p > 0.05）。在加载测试过程中，没有一种材料断裂。在义齿基托材料中，一种聚酰胺基聚合物（Valplast）表现出最高的变形，而PMMA基聚合物（Acrytone和Acron）表现出第二高的变形。
可以得出结论，义齿基托聚合物的弯曲性能存在相当大的差异。这可能有助于材料的抗疲劳性。
