Antimicrobial activity of alexidine, chlorhexidine and cetrimide against Streptococcus mutans biofilm

Abstract

BackgroundThe use of antimicrobial solutions has been recommended to disinfect demineralized dentin prior to placing the filling material. The aim of this study was to evaluate the ability of several antimicrobials in controlling Streptococcus mutans (SM) biofilm formed in dentin.MethodsAntimicrobial activity of 0.2% and 2% chlorhexidine (CHX), 0.2% cetrimide (CTR) and 0.2%, 0.5%, 1% and 2% alexidine (ALX) was assayed on 1-week SM biofilm formed on standardized coronal dentin blocks. Results of SM biofilm antimicrobial activity by different protocols were expressed as the kill percentage of biofilm and the term “eradication” was used to denote the kill of 100% of the bacterial population. To compare the efficacies of the different protocols the Student t test was used, previously subjecting data to the Anscombe transformation.ResultsAll ALX concentrations tested and 0.2% CTR achieved a kill percentage higher than 99%, followed by 2% CHX with percentages above 96% (no statistically significant difference among them). Whereas 2% ALX and 0.2% CTR respectively showed eradication in 10 and 9 of the twelve specimens, 0.2% CHX did not produce eradication in any case.ConclusionsThe present study shows that, when used for one minute, 2% and 1% alexidine, and 0.2% cetrimide, achieve eradication of Streptococcus mutans biofilm in most specimens when applied to a dentin-volumetric model.

Alexidine Dihydrochloride Attenuates Osteoclast Formation and Bone Resorption and Protects Against LPS-Induced Osteolysis

“…(13,14) AD exhibited antimicrobial activity toward Gram-positive and Gram-negative bacteria and bacterial biofilms by inducing lipid-phase separation and domain formation of bacterial membranes, leading to disruption of bacterial membrane fluidity. (15,16) In addition, AD has been shown to bind and neutralize LPS, thereby exhibiting potential anti-inflammatory effects. (17) More recently, AD was found to be a potent (IC 50 ¼ 1 mM) and selective inhibitor of the mitochondrial phosphatase, protein tyrosine phosphatase localized to the mitochondrion 1 (PTPMT1).…”

Microbicides Alter the Expression and Function of RND-Type Efflux Pump AdeABC in Biofilm-Associated Cells of Acinetobacter baumannii Clinical Isolates

“…The percentages of microbicide solutions used in our experiments corresponded to the Centers for Disease Control and Prevention recommendations (29) (e.g., 0.1 to 2% CT and 0.05 to 1% CHX) for disinfection of hard surfaces such as SSWs. Similar percentages of microbicide solutions were recently used effectively against biofilms formed by periodontal pathogens (30)(31)(32) and single strains of relevant Gram-positive and Gram-negative pathogens, including A. baumannii (33). Interestingly, A. baumannii biofilm-associated cells have shown resistance to CHX, but effective concentrations used to kill these bacterial cells are comparable to those used in this study (33).…”

Real-time assessment of Streptococcus mutans biofilm metabolism on resin composite

“…Since chlorhexidine gluconate (CHX) has been shown to be a potent antibacterial agent against S. mutans [28], an additional group of specimens (n=15) on which biofilms were grown in 0.65x THY medium supplemented with 0.1%(w/v) sucrose for 24 hours was treated with 2% CHX solution (CHX-Plus ™ , Inter-Med, Inc., USA) to serve as the control group. Specimens in that group were subjected to the same fabrication, polishing, sterilization, monomer extraction and biofilm growth protocols described in Sections 2.1 – 2.3 above.…”