【作者】 马莹莹； 邹朝晖； 陈阵； 李敏； 张蕾；

【Author】 MA Ying-ying,ZOU Zhao-hui,Li Min et al.(Dental Hospital of Tianjin Medical University, Tianjin 300070,China)

【机构】 天津医科大学口腔医院；

【摘要】 目的:观察不同功率密度HMME-PDT对大鼠模型防龋效果及牙髓组织的影响。方法用S.mutans感染Wistar大鼠口腔,并喂以致龋饲料2000#,建立龋齿模型。以70mW/cm2HMME-PDT、1 40mw/cm 2HMME-PDT、280 mW/cm 2HMME-PDT、单纯激光、单纯光敏剂为实验组,0.9%生理盐水为阴性对照组、0.2%氟化钠为阳性对照组。采用血卟啉单甲醚(Hematoporyrin monomethyl Ether,HMME)为光敏剂,532 nm半导体激光为光源,每周处理牙齿一次,5周后处死大鼠,拔除牙齿,记录Keyes龋齿计分,组织病理观察牙髓组织的变化。结果:Keyes龋齿计分显示:与阴性对照组相比,不同功率密度PDT组均有抑龋作用,且随着功率密度的增加,Keyes龋齿计分逐渐降低。组织病理观察:与阴性对照组相比,70mW/cm 2HMME-PDT组和1 40mw/cm 2HMME-PDT组,牙髓组织炎症或出血计分均没有明显的统计学差异(P>0.05),而280 mw/cm 2HMME-PDT组牙髓组织炎症或出血计分高,有统计学差异(P<0.05),随着功率密度的增大,牙髓组织的反应程度加重。本研究结果中,1 40mw/cm 2HMME-PDT既能有效的预防大鼠龋齿又不会造成牙髓组织的损伤。结论:HMME-PDT对大鼠龋齿有明显的预防作用,功率密度越大,预防效果越强,但功率密度越大越易引起牙髓的损伤,在以后的应用中要寻找合适的功率密度。更多还原

【Abstract】 OBJECTIVE:To evaluate the inhibitive effect of Photodynamic therapy with different parameters on dental caries formation and effect of endodontic tissue in rats. METHODS:Wistar were infected with S.mutans to establish the rat caries model.The rat’ s teeth were treated with PDT,laser,photosensitizer,0.9%NS,and 0.2%NaF once a week.HMME was used as the photosensitizer and semiconductor laser as the light source.The rats were sacrificed after five weeks.Keyes counts were used to measure the inhibitory effect of PDT on dental caries.Pathological section was used to evaluate changes of pulp tissue.RESULTS:Keyes counts showed that in comparison with the negative control,Keyes counts of PDT with different parameters could efficiently inhibit formation of caries.Additionally,Keyes scores reduced gradually with increasing of the laser power density.Pathological section showed that the scoring of 70mw/cm2HMME-PDT group and 140mw/cm2HMME-PDT group compared with negative control were not significantly different(P>0.05);The scoring of 280 mw/cm2HMME-PDT group were highly compared with negative control(P < 0.05).In our result,140mw/cm 2 was sufficient for the prevention of dental caries,which not only effectively inhibit dental caries,but also not change the pulp tissue.CONCLUSION:HMME-PDT had significant inhibitive efficacy on caries development in rats,with the power density increasing,the inhibitive efficacy was stronger,but large power density could change pulp tissue.So it is important to apply appropriate power density in the further treatment.更多还原