【作者】 李敏； 邹朝晖； 陈阵； 马莹莹； 张蕾；

【Author】 Li Min,Zou Zhao-hui,Chen Zhen,Ma Ying-ying,Zhang Lei(Dental Hospital of Tianjir Medical University,TianJin,300070,China)

【机构】 天津医科大学口腔医院；

【摘要】 目的:探讨以不同浓度血卟啉单甲醚(hematopo rphym monomethyl ether,HMME)作为光敏剂的光动力疗法(photodynamic therapy,PDT)对变形链球菌的抑制作用。方法:变形链球菌菌液分别与浓度为5μg/ml、1 0μg/ml、20μg/ml、40μg/ml、50μg/ml、60μg/ml的HMME孵育5分钟后,应用532 nm半导体激光器照射,能量密度为1 2.6J/cm2,然后对各浓度组菌液进行菌落计数,并与单纯光敏剂组、单纯激光组及空白对照组的菌落数进行比较,观察变形链球菌的抑制情况。结果:与单纯光敏剂组、单纯激光组及空白对照组的菌落数相比,不同浓度的HMME-PDT组的菌落数均明显减少(P<0.05),且HMME浓度在一定范围内(5μg/ml-40μg/ml),随着HMME浓度的升高,变形链球菌菌落数逐渐下降;超过此浓度范围PDT的杀菌效果未见明显增强。结论:HMME-PDT对体外变形链球菌具有明显的抑制作用,其效果和光敏剂的剂量密切相关,所以在防龋过程中必须寻找合适的光敏剂剂量。更多还原

【Abstract】 OBJECTIVE:To study the role of concentrations of hematoporphyrin monomethyl ether as photosensitizer of photodynamic therapy in inhibiting Streptococcus mutans(S.mutans).METHODS:The suspension of Streptococcus mutans were incubated with different concentrations(5μg/ml、10μg/ml、20μg/ml、40μg/ml、50μg/ ml、60μg/ml) of HMME for five minutes,then irradiated by the semiconductor laser (532nm,12.6J/cm2).Finally,the viable counts of S.mutans recorded by counting colony forming unit were compared among the HMME-PDT groups,photosensitizer-only group, laser-only group,and blank control group.RESULTS:The viable counts of Streptococcus mutans treated by different consentrations of HMME are reduced significantly compared with the photosensitizer-only group,laser-only group,and blank control group(P<0.05 ). The counts are reduced gradully with HMME concentration increasing from 5μg/ml to 40 Mg/ml,but there were no significant decreasing trends found when the HMME concentration continued increasing.CONCLUSION:In vitro,PDT has significant effects on inhibiting S.mutans and the effects are correlated with the dose of photosensitizer. So discovering proper photosensitizer concentration is a key step in applying PDT in the prevention of dental caries.更多还原