Antimicrobial effect of photo-activated disinfection therapy in vitro and in vivo studies

Abstract

目的利用體外實驗和臨床試驗評估光活化消毒技術(PAD)進行根管消毒的效果。方法體外選擇30顆單根管牙根建立糞腸球菌ATCC29212感染模型,分為3組。用PAD技術進行根管消毒并取樣,質量分數為2.5%的NaClO沖洗和生理鹽水沖洗分別作為陽性和陰性對照組。臨床選取50例慢性根尖周炎病例,隨機分為2組。根管預備時質量分數為2.5%的NaClO溶液沖洗。預備后組1采用PAD消毒,組2用生理鹽水沖洗。預備前后取樣,所有樣本接種于腦心浸液(BHI)培養基培養后記錄菌落數。結果體外實驗:PAD組細菌減少了99.86%,陽性對照組減少了100%,陰性對照組減少了96.94%。PAD組細菌回復10例均為陽性,陽性對照組6例,陰性對照組10例。臨床試驗:根管機械預備后細菌減少了99.98%。組1中PAD消毒后細菌培養均為陰性,組2細菌減少了36%。2組差異無統計學意義(P>0.05)。結論 PAD單獨使用可以降低根管內糞腸球菌的數量,但效果低于NaClO。臨床PAD技術輔助根管預備可以進一步降低細菌的數量。 To investigated the antimicrobial effect of photo-activated disinfection therapy（PAD）in association with endodontic treatment in vitro and in vivo studies. Methods In vitro study, 30 single-rooted teeth were selected and contaminated with Enterococcus faecalis ATCC29212. The specimens were randomly divided into 3 groups. PAD therapy, 2.5% NaClO irrigation（positive control） and saline solution（negative control） were used to disinfect the root canals in each group respectively. In vivo study, 50 single-root canals teeth were selected, and then randomly distributed into 2 groups. Each root canal was instrumented and irrigated with 2.5% NaClO. Then the root canals in group 1 were disinfected with PAD and the root canals in group 2 were irrigated with saline solution. Microbial sample was taken before and after instrumentation/irrigation and PAD therapy, plated onto the BHI agar and the colony forming units were counted. Results In vitro study, the bacterial counts reduced 99.86% after PAD disinfection compared with 100% in positive control group and 96.94% in negative control group. The recovery of bacteria was detected in 10 samples after PAD disinfection compared 6 samples in positive control group and 10 samples in negative control group. In vivo study, bacterial counts reduced 99.98% after instrumentation in two groups. After the PAD therapy, there was no positive colony forming units were detected in group 1, compared 36% ruduction in group 2. But no significantly difference was found between the two groups（P>0.05）. Conclusion PAD can decrease Enterococcus faecalis load in root canals, which is lower than NaClO. The use of PAD added to endodontic treatment leads to an enhanced decrease of bacterial load in infected root canals.