title: Antimicrobial effect of alexidine and chlorhexidine against Enterococcus faecalis infection.
abstract: A previous study demonstrated that alexidine has greater affinity for the major virulence factors of bacteria than chlorhexidine. The aim of this study was to compare the antimicrobial activity of 1% alexidine with that of 2% chlorhexidine using Enterococcus faecalis-infected dentin blocks. Sixty bovine dentin blocks were prepared and randomly divided into six groups of 10 each. E. faecalis was inoculated on 60 dentin blocks using the Luppens apparatus for 24 h and then the dentin blocks were soaked in 2% chlorhexidine or 1% alexidine solutions for 5 and 10 min, respectively. Sterile saline was used as a control. The antimicrobial efficacy was assessed by counting the number of bacteria adhering to the dentin surface and observing the degradation of bacterial shape or membrane rupture under a scanning electron microscope. Significantly fewer bacteria were observed in the 2% chlorhexidine- or 1% alexidine-soaked groups than in the control group (P<0.05). However, there was no significant difference in the number of bacteria adhering to the dentinal surface between the two experimental groups or between the two soaking time groups (P>0.05). Ruptured or antiseptic-attached bacteria were more frequently observed in the 10-min-soaked chlorhexidine and alexidine groups than in the 5-min-soaked chlorhexidine and alexidine groups. In conclusion, 10-min soaking with 1% alexidine or 2% chlorhexidine can be effective against E. faecalis infection.
authors.affiliation: Department of Conservative Dentistry, Dental Research Institute and BK21 Program, Seoul National University Dental Hospital, Seoul National University School of Dentistry, Seoul, Korea.
authors.forename: Hyun-Shik
authors.initials: HS
authors.lastname: Kim
authors.forename: Seok
authors.initials: S
authors.lastname: Woo Chang
authors.forename: Seung-Ho
authors.initials: SH
authors.lastname: Baek
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Han
authors.forename: Yoon
authors.initials: Y
authors.lastname: Lee
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhu
authors.forename: Kee-Yeon
authors.initials: KY
authors.lastname: Kum
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001422:Bacterial Adhesion / Q000187:drug effects; D058491:Bacterial Load / Q000187:drug effects; D001645:Biguanides / Q000494:pharmacology*; D002417:Cattle; D002462:Cell Membrane / Q000187:drug effects; D002710:Chlorhexidine / Q000494:pharmacology*; D003804:Dentin / Q000382:microbiology*; D013293:Enterococcus faecalis / Q000187:drug effects*; D008855:Microscopy, Electron, Scanning; D011897:Random Allocation; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D001645:Biguanides; C001570:alexidine; D002710:Chlorhexidine