RESUMO

Objective: To evaluate in the vitro effectiveness of three chemical agents for toothbrush disinfection. Material and Methods: Sixteen new toothbrushes were evaluated, previously sterilized and classified in five experimental groups (n=3) and one item as control. Three chemical agents were assessed: 0.12% Chlorhexidine gluconate (CHX), essential oil mouth rinse (Listerine) and 3.5% Sodium hypochlorite (NaOCl). The five selected strains were inoculated on toothbrushes and incubated for a 24 hours period and 37°C temperature in aerobic conditions. The incubated toothbrushes were immersed for a 15 min period into selected chemical agents and after drying in a controlled air stream, again re-cultured into enriched broth. A comparison was made between the initial and final microorganisms density recovered after chemical disinfection based on Mc Farland scale. The data obtained was compared by descriptive analysis and ANOVA methodology. Results: 3.5% NaOCl was the most effective chemical agent for toothbrush disinfection followed by CHX; Listerine was not effective to eliminate the inoculated bacteria in toothbrushes. Conclusion: 3.5% NaOCl and 0.12% CHX are the most effective chemical agents for toothbrush disinfection and Listerine was only effective against C. albicans.

Assuntos

RESUMO

Enterococcus faecalis es una bacteria en forma de coco dispuesta en cadenas o pares, Gram positiva, anaerobia facultativa, inmóvil y no esporulada que en años recientes, ha atraído la atención de diversos investigadores porque ha sido identificada como una causa frecuente de infección del sistema de conductos radiculares en dientes con fracaso en el tratamiento endodóntico. Una característica notable de esta especie la constituye su capacidad para sobrevivir y crecer en microambientes que pudieran ser tóxicos para otras bacterias, entre estos en presencia de Hidróxido de Calcio. Se ha sugerido que la resistencia de E. faecalis al Hidróxido de Calcio permite a esta bacteria sobrevivir en presencia del medicamento y proliferar cuando la acción de este finaliza, resultando en la colonización e infección del conducto radicular, y es por ello que el objetivo del presente estudio fue detectar e identificar a este microorganismo en dientes con fracaso en el tratamiento endodóntico. Para este fin, se seleccionaron 20 dientes obturados con conos de gutapercha y cemento a base de Hidróxido de Calcio, los cuales presentaban tratamiento endodóntico con fracaso. Como grupo control se seleccionaron 20 dientes con patología pulpar y/o periapical y que no habían sido tratados endodónticamente. Las muestras de los conductos radiculares fueron tomadas con conos de papel esterilizados, los cuales fueron colocados en caldo tioglicolato y posteriormente se sembraron en el medio Agar Enterococcus. Los medios fueron incubados en la estufa a 37ºC por 72 horas en condiciones de microaerofilia. La identificación definitiva de E. faecalis se realizó a través del sistema de identificación rápida API Rapid Strep. Los resultados obtenidos reflejaron que en 12 (60%) de los 20 dientes con fracaso en el tratamiento endodóntico se pudo detectar a E. faecalis, lo que permitió evidenciar la alta frecuencia con la cual se pudo encontrar a este microorganismo; no obstante, en el otro grupo de 20 dientes, también se encontró la bacteria en 5 de estos (25%). Estos resultados permitieron demostrar el papel preponderante de E. faecalis como agente ampliamente implicado en tratamientos endodónticos con fracaso.

Enterococcus faecalis is a coccal-shaped, Gram positive, facultative anaerobic and non motile bacteria. In recent years, several researchers have been interested in E. faecalis because this species has been identified like a frequent microorganism in endodontic treatment with failure. E. faecalis can growth and survive in presence of calcium hydoxide. Resistant capacity of E. faecalis to calcium hydroxide into root-filled teeth results in proliferation of this bacteria and subsecuently colonization and infection of root canal. The aim of this study was detect and identify this microorganism in teeth with failure in endodontic treatment. Twenty (20) root-filled teeth with guttapercha points and calcium hydroxide cement were selected. These teeth had endodontic tratments with failure. Control group was conformed by twenty (20) pulpar and/or periapical infection teeth without endodontic treatment. Samples of root canals were taken using sterile paper points, inoculated in tioglycolate broth media and growth obtained in this media were transferred to Agar Enterococcus plates and incubated at 37ºC for 72 hours in microaerofilical conditions. Identification of E. faecalis was possible by using API Rapid Strep identification kit. E. faecalis was isolated en 12 out of 20 teeth (60%) with endodontic failure, and also was found in 5 out of 20 teeth (25%) with pulpar and/or periapical infection. These findings relected the high frequency that E. faecalis was detected and identified in root-filled teeth with endodontic failure.