RESUMEN
OBJECTIVES: Recent molecular approaches have revealed that fastidious organisms such as Bacteroides forsythus and oral treponemes were frequently found in root canals with apical periodontitis. The purpose of this study was to identify the isolates of oral spirochetes at the species level in endodontic infections and to determine their association with B forsythus and Porphyromonas gingivalis. STUDY DESIGN: Seventy-nine teeth with apical periodontitis were selected for this study. After sampling from the root canals aseptically, polymerase chain reaction amplification for the 16S rRNA gene was performed with eubacterial universal primers. Subsequently, dot-blot hybridization was performed with 8 species-specific oligonucleotide probes. The microbial associations were analyzed by using the odds ratio. RESULTS: The most frequently found species was P gingivalis (27.4%), followed by Treponema maltophilum (26%), B forsythus (16.4%), and Treponema socranskii (2.7%). Other treponemes, including Treponema denticola, were not detected in our samples. Significant microbial associations were identified between T maltophilum, B forsythus, and P gingivalis by performing analysis with the odds ratio. CONCLUSION: Our results indicate that T maltophilum should be included in etiologic studies of endodontic diseases.
Asunto(s)
Bacteroides/clasificación , Necrosis de la Pulpa Dental/microbiología , Porphyromonas gingivalis/clasificación , Spirochaetales/clasificación , Adolescente , Adulto , Anciano , Bacteroides/genética , Niño , Intervalos de Confianza , Sondas de ADN , ADN Bacteriano/genética , Humanos , Immunoblotting , Persona de Mediana Edad , Hibridación de Ácido Nucleico , Oportunidad Relativa , Periodontitis Periapical/microbiología , Reacción en Cadena de la Polimerasa , Porphyromonas gingivalis/genética , ARN Ribosómico 16S/genética , Spirochaetales/genética , Treponema/clasificación , Treponema/genéticaRESUMEN
Sixty-eight standardized human root specimens were infected with Enterococcus faecalis for 3 wk after removal of the smear layer. After 3 wk of infection, the smear layer was reformed and in half of the specimens, the smear layer was again removed. Aqueous Ca(OH)2 paste and silicone oil based Ca(OH)2 paste were used as the test medications. The specimens were divided into four groups (i.e. (a) nonsmeared aqueous calcium hydroxide group, (b) nonsmeared silicon oil-based calcium hydroxide group, (c) smeared aqueous calcium hydroxide group, and (d) smeared silicon oil-based calcium hydroxide group. Medications were placed in the canals for 7 days. After removal of medications dentin chips were collected and incubated. The quantity of bacteria present was assessed. All calcium hydroxide pastes were effective in the elimination of bacteria in the dentinal tubules, except in the smeared group with silicone oil-based calcium hydroxide.