title: Antimicrobial Activity of Calcium Hydroxide and Betamethasone on Enterococcus faecalis; An in vitro Assessment.
abstract: BACKGROUND
  Calcium hydroxide (CH) is one of the most common intracanal medications. Corticosteroids (CS) are used in endodontics because of their anti-inflammatory activity. This study aimed to evaluate the antimicrobial effect of CH+betamethasone and CH+saline against Enterococcus faecalis (E. faecalis) using agar diffusion test and measuring the microbial zone of inhibition (ZOI).
  
  
  METHODS
  Four plates containing Mueller-Hinton broth and E. faecalis culture media, were prepared. In each plate, 5 holes (5×3 mm) were created and a creamy mixture of CH+betamethasone was inserted into the holes (10 holes for each material). Two holes with ampicillin disks and two empty holes were used as negative and positive controls, respectively. Plates were incubated for 24 h and then the diameter of microbial ZOI was measured. The pH of each mixture was measured by pH meter. Data were analyzed using the Mann-Whitney U test.
  
  
  RESULTS
  The mean diameter of ZOI for CH+betamethasone and CH+saline was 3.4 and 3 mm, respectively. The difference was not significant (P=0.143). The pH was 12.5 for CH+saline and 12.3 CH+betamethasone, respectively.
  
  
  CONCLUSIONS
  The mixture of CH+betamethasone had good antimicrobial effects against E. faecalis. Further studies are needed to confirm the value of this mixture in clinical settings.
authors.affiliation: Department of Endodontics, Dental School, Shahid Sadoughi University of Medical Sciences, Yazd, Iran;
authors.forename: Mahdi
authors.initials: M
authors.lastname: Tabrizizadeh
authors.affiliation: Private Practice, Yazd, Iran;
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Rasti
authors.affiliation: Department of Endodontics, Dental School, Shahid Sadoughi University of Medical Sciences, Yazd, Iran;
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Ayatollahi
authors.affiliation: Department of Pharmacology, Shahid Sadoughi University of Medical Sciences, Yazd, Iran;
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Mossadegh
authors.affiliation: Department of Pathobiology, Shahid Sadoughi University of Medical Sciences, Yazd, Iran;
authors.forename: Hengameh
authors.initials: H
authors.lastname: Zandi
authors.affiliation: Dental School, Shahid Sadoughi University of Medical Sciences, Yazd, Iran;
authors.forename: Farzad
authors.initials: F
authors.lastname: Dehghan
authors.affiliation: Medical Information and Library Science, Dental School, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Mousavi
keywords: Antimicrobial Activity; Betamethasone; Calcium Hydroxide; Enterococcus faecalis; Intracanal Medication