Mutans streptococci genetic strains in children with severe early childhood caries: follow-up study at one-year post-dental rehabilitation therapy
SHORT COMMUNICATIONElizabeth A. Palmer1, Alex Vo2†, Shelby B. Hiles1†, Patricia Peirano1†, Samyia Chaudhry3†, Amy Trevor2, Iraj Kasimi2, Jill Pollard2, Christopher Kyles2, Michael Leo4, Beth Wilmot5,6, John Engle1, John Peterson1, Tom Maier3,7 and Curtis A. Machida1,3*
1Department of Pediatric Dentistry, Oregon Health & Science University (OHSU) School of Dentistry, Portland, OR; 2Academic DMD Program, OHSU School of Dentistry, Portland, OR; 3Integrative Biosciences, OHSU School of Dentistry, Portland, OR; 4OHSU School of Nursing, Portland, OR; 5Oregon Clinical and Translational Research Institute, OHSU, Portland, OR; 6Division of Bioinformatics and Computational Biology, Department of Medical Informatics and Clinical Epidemiology, OHSU School of Medicine, Portland OR; 7Oral Pathology and Radiology, OHSU School of Dentistry, Portland, OR
Abstract
Background: Genotypic strains of cariogenic mutans streptococci (MS) may vary in important virulence properties. In previous published studies, we identified 39 MS strains from pediatric patients undergoing full-mouth dental rehabilitation, including the removal and/or repair of carious lesions and application of antimicrobial rinse and fluoride varnish.Objectives: The objectives of this current 1-year follow-up study are to assess the variability of MS strains that occur at 1-year post-rehabilitation and characterize the xylitol-resistance properties of MS strains that predominate.
Methods: Plaque from five children with severe early childhood caries was collected 1-year post-rehabilitation. MS isolates were subjected to arbitrarily primed-polymerase chain reaction (AP-PCR) for identification of genetic strains and in vitro xylitol-inhibition experiments. To more precisely define strain distributions within each patient, we isolated large numbers of isolates per patient.
Results: MS strains diminished from several strains pre-rehabilitation, to one dominant strain at 1-year post-rehabilitation, with several new emergent strains. The majority of the clinical MS strains, as well as the Streptococcus mutans laboratory strains ATCC 25175 and 35668, were predicted to undergo 50% inhibition with 2.48–5.58% xylitol, with some clinical MS strains being significantly more resistant in vitro.
Conclusions: Our follow-up study using patients from the original cohort demonstrates that specific MS strains are dominant at 1-year post-dental rehabilitation. Most of the clinical MS strains are similar in xylitol resistance to the attenuated S. mutans ATCC control strains, with some strains being more resistant to xylitol in vitro.
Keywords: mutans streptococci; distribution of genotypic MS strains; Streptococcus mutans; oral streptococci; severe early childhood caries; full-mouth dental rehabilitation therapy
Link to full text
Citation: Journal of Oral Microbiology 2012, 4: 19530 - http://dx.doi.org/10.3402/jom.v4i0.19530
No comments:
Post a Comment