title: The effect of different root canal medicaments on the elimination of Enterococcus faecalis ex vivo.
abstract: OBJECTIVE
  The aim of this study was to evaluate the antimicrobial effect of chlorhexidine gel (CHX-G) 2%, chlorhexidine powder (CHX-P) 1%, povidone-iodine (PVP-I), polyhexanide and camphorated-and-mentholated chlorophenol (ChKM) ex vivo.
  
  
  METHODS
  For every medicament group 10 root segments (15 mm long) of extracted human teeth were prepared to ISO-size 45 and sterilized (n = 50). The root segments were then inoculated with Enterococcus faecalis and aerobically incubated at 37°C. After 1 week, ten root canals were filled with one of the medicaments, respectively and aerobically incubated at 37°C for another week. Ten teeth served as positive controls and were filled with sterile saline solution. After 7 days, the medicaments were inactivated and all root canals were instrumented to ISO-size 50. The obtained dentin samples were dispersed in Ringer solution followed by the preparation of serial dilutions. 10 μl per sample were applied to an agar plate and incubated at 37°C for 48 h. The colony forming units were counted and the reduction factors (RFs) were calculated and statistically analyzed.
  
  
  RESULTS
  Compared with the positive controls all medicaments exhibited an antibacterial effect against E. faecalis. The RFs for CHX-G, CHX-P and ChKM were significantly higher compared to PVP-I and polyhexanide (P < 0.05). In contrast to PVP-I and polyhexanide, CHX-G, CHX-P and ChKM were able to eliminate E. faecalis from all dentin samples.
  
  
  CONCLUSIONS
  Within the limitations of this ex vivo investigation, 2% CHX-G and CHX-P were as effective as ChKM against E. faecalis. Thus, when choosing a root canal medicament the better biocompatibility of CHX compared with ChKM should be taken in consideration.
authors.affiliation: Department of Operative Dentistry, Westphalian Wilhelms-University Münster, Germany.
authors.forename: Till
authors.initials: T
authors.lastname: Dammaschke
authors.affiliation: Private Practice, Berlin, Germany.
authors.forename: Nina
authors.initials: N
authors.lastname: Jung
authors.affiliation: Department of Periodontology, Westphalian Wilhelms-University, Münster, Germany.
authors.forename: Inga
authors.initials: I
authors.lastname: Harks
authors.affiliation: Central Interdisciplinary Ambulance in the School of Dentistry, Münster, Germany.
authors.forename: Edgar
authors.initials: E
authors.lastname: Schafer
keywords: Camphorated-and-mentholated chlorophenol; chlorhexidine; polyhexanide; povidone-iodine; root canal medication