Xu Hockin H K, Quinn Janet B, Giuseppetti Anthony A, Eichmiller Frederick C, Parry Edward E, Schumacher Gary E
Paffenbarger Research Center, American Dental Association Foundation, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
Dent Mater. 2004 Mar;20(3):220-7. doi: 10.1016/S0109-5641(03)00096-4.
Recent studies used silica-fused whiskers to increase the strength and toughness of resin composites. This study investigated the three-body wear of whisker composites. It was hypothesized that the whisker composites would be more wear resistant than composites reinforced with fine glass particles, and the whisker-to-silica filler ratio would significantly affect wear.
Silica particles were mixed with silicon nitride whiskers at seven different whisker/(whisker + silica) mass fractions (%): 0, 16.7, 33.3, 50, 66.7, 83.3, and 100. Each mixture was heated at 800 degrees C to fuse the silica particles onto the whiskers. Each powder was then silanized and incorporated into a dental resin to make the wear specimens. A four-station wear machine was used with specimens immersed in a slurry containing polymethyl methacrylate beads, and a steel pin was loaded and rotated against the specimen at a maximum load of 76 N.
Whisker-to-silica ratio had significant effects (one-way ANOVA; p < 0.001) on wear. After 4 x 10(5) wear cycles, the whisker composite at whisker/(whisker + silica) of 16.7% had a wear scar diameter (mean +/- sd; n = 6) of (643 +/- 39) microm and a wear depth of (82 +/- 19) microm, significantly less than a wear scar diameter of (1184 +/- 34) microm and a wear depth of (173 +/- 15) microm of a commercial prosthetic composite reinforced with fine glass particles (Tukey's multiple comparison). SEM examination revealed that, instead of whiskers protruding from the worn surface, the whiskers were worn with the composite surface, resulting in relatively smooth wear surfaces.
Silica-fused whisker reinforcement produced dental resin composites that exhibited high resistance to wear with smooth wear surfaces. These properties, together with the strength and fracture toughness being twice those of current glass particle-reinforced composites, may help extend the use of resin composite to large stress-bearing posterior restorations.
近期研究使用二氧化硅熔合晶须来提高树脂复合材料的强度和韧性。本研究调查了晶须复合材料的三体磨损情况。研究假设是晶须复合材料比用细玻璃颗粒增强的复合材料更耐磨，且晶须与二氧化硅填料的比例会显著影响磨损。
将二氧化硅颗粒与氮化硅晶须按七种不同的晶须/（晶须 + 二氧化硅）质量分数（%）混合：0、16.7、33.3、50、66.7、83.3和100。每种混合物在800℃下加热，使二氧化硅颗粒熔合到晶须上。然后对每种粉末进行硅烷化处理，并将其掺入牙科树脂中制成磨损试样。使用四工位磨损试验机，将试样浸入含有聚甲基丙烯酸甲酯珠粒的浆料中，加载一根钢针并使其以76 N的最大载荷对着试样旋转。
晶须与二氧化硅的比例对磨损有显著影响（单因素方差分析；p < 0.001）。在4×10⁵次磨损循环后，晶须/（晶须 + 二氧化硅）为16.7%的晶须复合材料的磨损疤痕直径（平均值±标准差；n = 6）为（643±39）μm，磨损深度为（82±19）μm，显著小于用细玻璃颗粒增强的商业修复复合材料的磨损疤痕直径（1184±34）μm和磨损深度（173±15）μm（Tukey多重比较）。扫描电子显微镜检查显示，晶须不是从磨损表面突出，而是与复合材料表面一起磨损，从而产生相对光滑 的磨损表面。
二氧化硅熔合晶须增强技术制备的牙科树脂复合材料表现出高耐磨性且磨损表面光滑。这些特性，再加上其强度和断裂韧性是当前玻璃颗粒增强复合材料的两倍，可能有助于将树脂复合材料的应用扩展到大应力承载的后牙修复。
Zotero 插件