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Antibiotic resistance in primary and persistent endodontic infections
Gretchen B Jungermann1, Krystal Burns, Renu Nandakumar
1Department of Endodontics, Dental School, University of Maryland, Baltimore, Maryland 21201, USA.
Journal of Endodontics
|September 20, 2011
Summary
Antibiotic resistance genes were identified in endodontic infections. Contemporary endodontic treatments significantly reduced most identified genes, except for tetM, highlighting potential for genetic screening.
Area of Science:
- Microbiology
- Endodontics
- Genetics
Background:
- Antibiotic resistance genes (ARGs) in endodontic infections can reduce treatment efficacy.
- Identifying ARGs is crucial for understanding treatment resistance.
Purpose of the Study:
- To identify specific ARGs in primary and persistent endodontic infections.
- To evaluate the effectiveness of endodontic procedures in eliminating bacteria carrying these ARGs.
Main Methods:
- Root canal samples were collected pre- and post-treatment from patients undergoing endodontic procedures.
- Polymerase chain reaction (PCR) was used to detect ARGs: bla(TEM-1), cfxA, blaZ, tetM, tetW, tetQ, vanA, vanD, and vanE.
- Phenotypic identification and antibiotic susceptibility testing were also performed.
Main Results:
- bla(TEM-1) was more prevalent in primary infections pre-treatment.
- Overall prevalence of detected ARGs significantly decreased post-treatment (P < .001).
- bla(TEM-1), tetW, cfxA, blaZ, and tetQ showed significant reductions or elimination, while tetM remained unchanged. Vancomycin resistance genes (vanA, vanD, vanE) were absent.
Conclusions:
- bla(TEM-1) is more common in primary endodontic infections.
- Current endodontic treatments effectively reduce many ARGs, but tetM persistence warrants further investigation.
- Genetic testing may serve as a valuable screening tool for antibiotic resistance in endodontics.
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