title: Antimicrobial effect and pH of chlorhexidine gel and calcium hydroxide alone and associated with other materials.
abstract: The purposes of this study were to evaluate the effectiveness of 2% chlorhexidine (CHX) gluconate gel, calcium hydroxide [Ca(OH)2] and their combination with iodoform and zinc oxide powder as intracanal medications against select microorganisms, and to measure the pH changes caused by these medications. Antimicrobial activity was determined by the agar diffusion method. The zones of growth inhibition were measured and the results were analyzed statistically by Kruskal-Wallis test (p<0.05). The pH of the pastes was measured right after preparation, after 24 h and 1 week later. The largest mean zones of microbial inhibition were produced by 2% CHX gel, followed by Ca(OH)2 + 2% CHX gel + iodoform, Ca(OH)2 + 2% CHX gel, Ca(OH)2 + 2% CHX gel + zinc oxide, and Ca(OH)2 + water. The mean pH of all medications stayed above 12.0 during the whole experiment, except for CHX gel (pH=7.0). The results of this study showed that all medications had antimicrobial activity, but the most effective against the tested microorganisms were 2% CHX gel, followed by its combination with Ca(OH)2 and iodoform.
authors.affiliation: Endodontic Area, Department of Restorative Dentistry, School of Dentistry of Piracicaba, State University of Campinas, Piracicaba, SP, Brazil.
authors.forename: Francisco José
authors.initials: FJ
authors.lastname: de Souza-Filho
authors.forename: Adriana de Jesus
authors.initials: Ade J
authors.lastname: Soares
authors.forename: Morgana Eli
authors.initials: ME
authors.lastname: Vianna
authors.forename: Alexandre Augusto
authors.initials: AA
authors.lastname: Zaia
authors.forename: Caio Cezar Randi
authors.initials: CC
authors.lastname: Ferraz
authors.forename: Brenda Paula Figueiredo de Almeida
authors.initials: BP
authors.lastname: Gomes
mesh_terms: D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D002126:Calcium Hydroxide / Q000008:administration & dosage / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects; D002710:Chlorhexidine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D015169:Colony Count, Microbial; D003764:Dental Materials / Q000494:pharmacology; D004338:Drug Combinations; D013293:Enterococcus faecalis / Q000187:drug effects; D006801:Humans; D006847:Hydrocarbons, Iodinated / Q000008:administration & dosage / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D016966:Porphyromonas gingivalis / Q000187:drug effects; D018713:Prevotella intermedia / Q000187:drug effects; D012388:Root Canal Irrigants / Q000494:pharmacology*; D013053:Spectrophotometry; D013295:Streptococcus mutans / Q000187:drug effects; D013298:Streptococcus sanguis / Q000187:drug effects; D016986:Streptococcus sobrinus / Q000187:drug effects; D013997:Time Factors; D015034:Zinc Oxide / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D000891:Anti-Infective Agents, Local; D003764:Dental Materials; D004338:Drug Combinations; D006847:Hydrocarbons, Iodinated; D012388:Root Canal Irrigants; C010473:iodoform; C010882:chlorhexidine gluconate; D002126:Calcium Hydroxide; D002710:Chlorhexidine; D015034:Zinc Oxide