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目的研究无机填料含量对流动树脂的挠曲强度和压缩强度的影响。方法于2012年4月在北京大学口腔医学院口腔材料研究室测定Clearfil Flow、Filtek Flow、DenFil Flow、Filtek Z250复合树脂无机填料的质量分数、挠曲强度和压缩强度。结果流动树脂中无机填料的质量分数与其挠曲强度的变化顺序相一致,由小到大依次为DenFil Flow、Filtek Flow、Clearfil Flow、Filtek Z250。DenFil Flow与其余3组间挠曲强度差异均有统计学意义（P〈0.05）,Filtek Flow与Clearfil Flow、Filtek Z250间挠曲强度差异亦均有统计学意义（P〈0.05）,但Clearfil Flow与Filtek Z250间挠曲强度差异无统计学意义（P〉0.05）。4种材料压缩强度差异均无统计学意义（P〉0.05）。结论高填料型流动树脂的挠曲强度远高于普通流动树脂,并且可达到我国医药行业标准规定面修复材料的要求;压缩强度与前后牙通用树脂相近,可以满足临床应用的需要。

An in vitro investigation of the influence of filler volume upon flexural strength and compressive strength of flowable composite

Objective To evaluate the influence of filler volume upon the flexural strength and compressive strength of flowable composites. Methods The tested products were Clearfil Flow,Filtek Flow,DenFil Flow and Filtek Z250. Flexural strength and compressive strength of resins were calculated and filler percentages of resins were calculated after the latter was incinerated at 700 degrees C. Result When the filler percentages of resins increased,the hardness of resins increased too. The weight percentage of fillers of flowable composites was as follows：Clearfil Flow：76.50,Filtek Flow：60.90,DenFil Flow：58.86. Compared with traditional flowable composite,the flexural strength of flowable composite with more filler increased significantly. Clearfil Flow：（103.73±14.53）MPa,Filtek Flow：（85.72±14.23）MPa,DenFil Flow（67.23±11.45）MPa. The compressive strength of flowable composite with more fillers approached to traditional flowable composite and universal composite without significantly difference. Conclusion The flexural strength of flowable composite with more filler increases significantly compared with traditional flowable;the compressive strength approaches to traditional flowable composite and universal composite.