ABSTRACT
The aim of this study was to investigate the antimicrobial activity of calcium hydroxide (Ca(OH)2) combined with 2% chlorhexidine gluconate (CHX) gel against endodontic pathogens and to compare the results with the ones achieved by Ca(OH)2 mixed with sterile water and by CHX gel alone. Two methods were used: the agar diffusion test and the direct contact test. Ca(OH)2 + 2% CHX gel produced inhibitory zones ranging from 2.84 to 6.5 mm, and required from 30 seconds to 6 hours to eliminate all tested microorganisms. However, 2% CHX gel showed the largest microbial growth zones from 4.33 to 21.67 mm, and required 1 minute or less to inhibit all tested microorganisms. A paste of Ca(OH)2 plus sterile water inhibited only the microorganisms with which it was in direct contact and required from 30 seconds to 24 hours to kill all tested microorganisms. In conclusion, 2% CHX gel + Ca(OH)2 showed better antimicrobial activity than Ca(OH)2 manipulated with sterile water.
Subject(s)
Anti-Infective Agents, Local/pharmacology , Bacteria/drug effects , Root Canal Irrigants/pharmacology , Calcium Hydroxide/pharmacology , Candida albicans/drug effects , Chlorhexidine/pharmacology , Dental Pulp Cavity/microbiology , Drug Combinations , Enterococcus faecalis/drug effects , Immunodiffusion , Porphyromonas endodontalis/drug effects , Porphyromonas gingivalis/drug effects , Prevotella intermedia/drug effects , Staphylococcus aureus/drug effectsABSTRACT
O objetivo deste estudo foi avaliar in vitro a atividade antimicrobiana do hidróxido de cálcio [Ca(OH)2] em associação com diferentes veículos frente a patógenos endodônticos. O teste de difusão em caldo foi utilizado. Foram preparadas pastas com pó de Ca(OH)2 e os seguintes veículos: água destilada, glicerina, PMCC (paramonoclorofenol canforado), PMCC + glicerina, e PMCC + polietilenoglicol. O tempo necessário para as pastas produzirem culturas negativas frente aos microorganismos testados foi registrado e analisado estatisticamente por meio do teste de Kruskal Wallis com nível de significância de 5%. Foram necessárias de 6 a 24 h para eliminar os microrganismos aeróbios e facultativos e de 30 s a 5 min para os anaeróbios estritos. A suscetibilidade microbiana em ordem crescente foi: Enterococcus faecalis (patógeno mais resistente), Candida albicans, Staphylococcus aureus, Porphyromonas gingivalis, Porphyromonas endodontalis e Prevotella intermedia (os últimos dois microrganismos necessitaram do mesmo tempo para serem eliminados). Concluiu-se que as pastas de hidróxido de cálcio necessitaram de maior tempo para eliminar os microrganismos facultativos do que os anaeróbios. Esses achados sugerem que a propriedade antimicrobiana está relacionada tanto à formulação da pasta quanto à suscetibilidade microbiana.
Subject(s)
Calcium Hydroxide , In Vitro Techniques , Root Canal Irrigants , Tooth, Nonvital , Anti-Bacterial Agents , Bacteria, Aerobic , Disease SusceptibilityABSTRACT
The aim of this study was to investigate in vitro the antimicrobial activity of calcium hydroxide [Ca(OH)2] in combination with different vehicles against endodontic pathogens. For such purpose, a broth dilution test was performed. Pastes were prepared with Ca(OH)2 powder and the following vehicles: sterile water, glycerin, camphorated monochlorophenol (CMCP), CMCP + glycerin, polyethyleneglycol and CMCP + polyethyleneglycol. The time required for the pastes to produce negative cultures against the tested microorganisms was recorded and analyzed statistically using the Kruskal Wallis test at 5% significance level. Timing for pastes to eliminate the aerobic and facultative anaerobic microorganisms ranged from 6 to 24 h, while strict anaerobic microorganisms were inhibited within 30 s to 5 min. Microbial susceptibility, ranked from weakest to strongest, can be presented as follows: Enterococcus faecalis (the most resistant microorganism), Candida albicans, Staphylococcus aureus, Porphyromonas gingivalis, Porphyromonas endodontalis and Prevotella intermedia (the last two microorganisms required the same time to be eliminated). In conclusion, calcium hydroxide pastes needed more time to eliminate facultative than anaerobic microorganisms. These findings suggest that the antimicrobial property is related both to paste formulation and to microbial susceptibility.
