添加纳米二氧化钛树脂基托材料抗菌性能的研究

目的：研究纳米二氧化钛树脂基托在体外对变形链球菌和白色念珠菌的抗菌效果。方法：在聚甲基丙烯酸甲酯基托树脂粉中添加以1％，3％，5％不同比例的纳米二氧化钛抗菌剂，制成树脂基托。采用薄膜密着法，分别测试添加抗菌成分后，树脂基托对变形链球菌和白色念珠菌的抗菌活性。测定纳米二氧化钛对变形链球菌和白色念珠菌的最小抑菌浓度，测含3种不同比例的二氧化钛抑菌浓度。结果：采用薄膜密着法对抗菌效果进行测试，对变形链球菌的抗菌率分别为：64．9％，93．2％，97．3％，对白色念珠菌的抗菌率分别为：66．2％，95．4％，100％。采用时效法测试时间长短对材料的影响，结果显示时间对材料无统计学差异。光照法对树脂材料测试在紫外光线下变形链球菌、白色念珠菌抗菌率均达100％，变形链球菌强光下达到98％，白色念珠菌达99％。变形链球菌自然光线下达到95％，白色念珠菌达97％。变形链球菌暗环境下达到93％，白色念珠菌达95％。结论：树脂基托在体外表现了一定的抗变形链球菌和抗白色念珠菌的效果，当树脂基托中抗菌剂的浓度达到3％时，即可达到满意抗菌效果。采用薄膜密着法对进行抗菌性能的评价具有可行性。

Antibacterial activities of polymethylmethacrylate denture base materials impregnated with nano titanium dioxide

Objective:To study the anti candida albicans and anti streptococcus mutans activities in vitro of polymethy-lmethacrylate denture base materials impregnated with nano titanium dioxide.Method:Nano titanium dioxide was added into polymethylmethacrylate powder as antibacterial respectively in the ratio of 1%,3%,5%,and then three types of denture bases were made using the three types of powders.Their antibacterial effects and the minimum inhibitory concentration were tested using a method according to the Japanese standards JISZ2801-2000.Bacteria strains used included candida albicans & streptococcus mutans.Result:The antibacterial ratios of three types of denture bases against candida albicans and anti streptococcus mutans were 64.9%&66.2%,93.2%&97.3%,and95.4%&100%,respectively.According to results about their antibacterial effects vs the time,there were no statistical differences between the different time.According to the results gotten by illumination method,the antibacterial ratios(anti streptococcus mutans and anti candida albicans of the polymethylmethacrylate material were 100%&100% in the ultraviolet,98% & 99% in the high irradiance,95% and 97% in the natural lighting,93% and 95% in the darkness.Conclusion:The polymethylmethacrylate denture base materials impregnated with nano titanium dioxide shows some antibacterial effects in vitro.When the content of the antimicrobials in the polymethylmethacrylate denture base reached 3%,a satisfying antibacterial effects can be gotten.The method used in this study according to the Japanese standards JISZ2801-2000 was practicable to test the antibacterial activity.