过氧乙酸消毒剂对牙胶尖消毒效果的实验研究

Study on the disinfection effects of peracetic acid solutions on gutta-percha cones

目的初步评价过氧乙酸消毒剂(Peracetic Acid,PAA)对牙胶尖的消毒效果。方法将800根牙胶尖随机分成5组,分别浸入金黄色葡萄球菌、大肠杆菌、粪肠球菌、枯草杆菌黑色变种芽孢以及白色念珠菌制成的菌悬液进行体外感染,每组160根牙胶尖再分成4小组,分别用0.1%、0.2%、0.5%过氧乙酸溶液和5.25%次氯酸钠溶液(Sodium Hypochlorite,NaOCl)浸泡消毒,在消毒后15s、30s、1min、2min时分别取出10根牙胶尖进行微生物培养,根据培养后有无微生物生长评定消毒效果。结果 0.1%或0.2%过氧乙酸浸泡消毒2min后无法杀灭枯草杆菌黑色变种芽孢;0.5%过氧乙酸或5.25%次氯酸钠浸泡消毒2min后,牙胶尖上5种微生物都被杀灭;对枯草杆菌黑色变种芽孢污染的牙胶尖消毒15s时,0.5%过氧乙酸的消毒效果明显好于5.25%次氯酸钠,但在其它情况下两者的消毒效果无统计学差异。结论用0.5%过氧乙酸浸泡消毒2min后,能有效杀灭牙胶尖表面微生物,可考虑用于临床上牙胶尖的快速消毒。

Objective To preliminarily evaluate the disinfection effects of peracetic acid on gutta-percha cones. Methods 800 gutta-percha cones were used in this study and divided into 5 groups of 160 each, each group was respectively infected in vitro by the five kinds of microorganisms （S. aureus, E. coli, E. faecalis, B. subtilis spores or C. albicans）. After infection, 160 gutta-percha cones in each group was subdivided into 4 groups and then respectively treated with solution （0.1%PPA, 0.2%PPA, 0.5%PPA or 5.25%NaOCl）. At 15s, 30s, 1min or 2min after exposure to each solution, the microorganisms （S. aureus, E. coli, E. faecalis, B. subtilis spores or C. albicans） in gutta-percha cones （n=10） was counted after culturing to assess the disinfection ef？ciency of the treating solution. Results 0.1% or 0.2% peracetic acid was not effective on eliminating B. subtilis spores on gutta-percha cones after 2 minutes of contact with the disinfectant. 0.5% peracetic acid or 5.25% sodium hypochlorite eliminated all microorganisms tested after 2 minutes of disinfection. 0.5% peracetic acid showed better ef？ciency than 5.25% sodium hypochlorite in killing B. subtilis spores at 15s exposure, while no signi？cant differences was observed in other case between the two groups. Conclusion The study suggested that 0.5% peracetic acid solution was effective in eliminating the tested microorganisms on the surface of gutta-percha cones at after 2-min of exposure.