In vitro study of the antibacterial effect of the Povidone iodine on the Enterococcus faecalis in the root canal

WU Hao-ze; YANG Si-rui; LI Fen; CHENG Xiao-gang; ZHANG Mai; WANG Luo-qianhui; LI Na

doi:10.15956/j.cnki.chin.j.conserv.dent.2024.10.003

Abstract：AIM:Compare the antibacterial effects of 1％PVP-I,2.5％NaClO,and physiological saline on the Enterococcus faecalis in infected root canals,and explore the feasibility of using povidone iodine as root canal irrigation solution in the refractory apical periodontitis.METHODS:The Enterococcus faecalis cultured in vitro in both planktonic and biofilm states.The study was divided into three groups:1％PVP-I group,2.5％NaClO group,and physiological saline group(n=6).After treating with the three types of irrigation solutions mentioned above,the effects of each group on the growth of planktonic Enterococcus faecalis or biofilm were compared by measuring growth curves and colony forming unit counts.18 single mandibular premolars extracted during orthodontic treatment were collected,prepared as root model,and infected by inoculating with Enterococcus faecalis.After treating with the three types of irrigation solutions mentioned above,the antibacterial effects of each group of irrigation solutions on the biofilm of Enterococcus faecalis in the root canal were observed by SEM and CLSM.RESULTS:The antibacterial effect of 1％PVP-I and 2.5％NaClO on the growth of Enterococcus faecalis in planktonic and biofilm states was significantly stronger than that of the physiological saline group(P＜0.05),but there was no statistical difference between the 1％PVP-I group and the 2.5％NaClO group(P＞0.05).SEM observation results show that 1％PVP-I and 2.5％NaClO can effectively inhibit the colonization of Enterococcus faecalis on the surface of root canals.CLSM observation results show that 2.5％NaClO and 1％PVP-I are available to inhibit the growth activity of Enterococcus faecalis colonizing in the depth of dentinal tubules.CONCLUSION:1％PVP-I successfully inhibit the colonization of Enterococcus faecalis resident in the root canal,and can be used as irrigation solutions for infected root canals in the refractory apical periodontitis in clinical practice.