RESUMO
The aim of this study was to isolate and detect microorganisms of root-filled teeth associated with periradicular lesions. Specimens were sampled from patients undergoing root canal retreatment. The bacteria were characterized by morphologic and biochemical analysis and by 16S rRNA gene sequencing. Microorganisms were detected in 10 of 18 teeth. The majority of positive samples revealed a mixed culture of 2-8 species. In 2 teeth Enterococcus faecalis was the only detected species. For the first time Vagococcus fluvialis was detected in root canals. Solobacterium moorei and Fusobacterium nucleatum were the most prevalent species. Presence of F. nucleatum was associated with the presence of S. moorei in 5 of 7 cases. In all teeth with Parvimonas micra and Dialister invisus, F. nucleatum and S. moorei were found. Moreover, members of additional different genera were detected delivering bacterial compositions that have been not described yet.
Assuntos
Cavidade Pulpar/microbiologia , Periodontite Periapical/microbiologia , Dente não Vital/microbiologia , Adulto , Idoso , Técnicas de Tipagem Bacteriana , Contagem de Colônia Microbiana , DNA Bacteriano/análise , Fusobacterium nucleatum/isolamento & purificação , Bacilos Gram-Positivos Asporogênicos/isolamento & purificação , Bacilos Gram-Positivos Asporogênicos/patogenicidade , Cocos Gram-Positivos/isolamento & purificação , Cocos Gram-Positivos/patogenicidade , Humanos , Pessoa de Meia-Idade , Periodontite Periapical/terapia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Retratamento , Tratamento do Canal RadicularRESUMO
This study determined the presence of microorganisms by culture and polymerase chain reaction in asymptomatic root-filled teeth with periradicular lesions. Furthermore, a disinfecting regimen using sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA), chlorhexidine digluconate (CHX) irrigation, and calcium hydroxide (Ca(OH)(2)) dressing was assessed. After removal of the root-filling material, specimens of 20 cases undergoing retreatment were sampled. Moreover, the canals were sampled after each step of the disinfecting regimen. Prevalence of microorganisms was 60% by culture and 65% by polymerase chain reaction. In four of those samples (31%), DNA of Enterococcus faecalis was found. After further root canal preparation and irrigation using NaOCl and EDTA, microorganisms could be detected in none of the teeth. Thus, CHX and Ca(OH)(2) could not show further disinfection. In contrast, microorganisms were found in two teeth after the interappointment dressing. It may be concluded that proper root canal preparation and irrigation using NaOCl and EDTA are sufficient for decontamination of the root canal system during endodontic retreatment.
