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Oral Biofilm Analysis of Palatal Expanders by Fluorescence In-Situ Hybridization and Confocal Laser Scanning Microscopy
Published on: October 20, 2011
Microorganisms in root canal-treated teeth from a German population.
Isabela N Rôças1, Michael Hülsmann, José F Siqueira
1Department of Endodontics, Estácio de Sá University, Rio de Janeiro, Brazil; Department of Molecular Microbiology, Estácio de Sá University, Rio de Janeiro, Brazil.
Journal of Endodontics
|July 19, 2008
Summary
Persistent intraradicular infection is linked to posttreatment apical periodontitis. This study found diverse bacteria, including Streptococcus and Treponema denticola, in treated root canals, confirming infection
Area of Science:
- Microbiology
- Endodontics
- Infectious Diseases
Background:
- Posttreatment apical periodontitis often stems from persistent or secondary intraradicular infections.
- Understanding the microbial etiology is crucial for effective treatment strategies.
Purpose of the Study:
- To identify and quantify bacterial taxa in root canals of teeth with posttreatment apical periodontitis.
- To investigate the prevalence of Enterococcus faecalis and Candida albicans in these cases.
Main Methods:
- Utilized 16S ribosomal RNA (rRNA) gene probes in a reverse-capture checkerboard hybridization assay.
- Employed species-specific polymerase chain reaction (PCR) for Enterococcus faecalis and Candida albicans detection.
- Analyzed samples from German patients with treated root canals and apical periodontitis.
Main Results:
- Bacterial DNA was present in all analyzed samples.
- Twenty of 28 bacterial taxa were detected, with Streptococcus species, Lactobacillus species, Dialister invisus, Eubacterium infirmum, Prevotella intermedia, Selenomonas sputigena, Synergistes oral clone BA121, and Treponema denticola being frequently identified.
- Enterococcus faecalis was found in 47% of cases, and Candida albicans in 6%.
- Streptococci and Treponema denticola were the most prevalent among taxa found at high levels (>10^5).
Conclusions:
- Confirms a strong association between persistent/secondary intraradicular infection and posttreatment apical periodontitis.
- Most cases presented with polymicrobial infections, with Enterococcus faecalis not being the dominant species when present.
- Suggests the involvement of various detected bacterial taxa in the etiology of posttreatment apical periodontitis.
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