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Phenotypic heterogeneity of Streptococcus mutans in dentin
1Department of Operative Dentistry, Periodontology and Preventive Dentistry, Saarland University, D-66421 Homburg, Germany. Stefan.Rupf@uniklinikum-saarland.de
Journal of Dental Research
|November 26, 2008
Summary
Restorative treatment increases Streptococcus mutans phenotypic heterogeneity in carious dentin. This adaptation of oral bacteria to the modified environment under dental restorations suggests a need for further investigation into treatment impacts.
Area of Science:
- Microbiology
- Dental Research
- Bacterial Phenotyping
Background:
- Phenotypic heterogeneity of Streptococcus mutans in carious dentin is not well understood.
- Matrix-assisted laser-desorption/ionization-time-of-flight mass-spectrometry (MALDI-TOF-MS) is a key technology for bacterial differentiation.
Purpose of the Study:
- To investigate the influence of restorative treatment on the phenotypic heterogeneity of Streptococcus mutans.
- To compare S. mutans phenotypes before and after temporary restoration removal in deciduous molars.
Main Methods:
- Isolation and comparison of 222 S. mutans strains from dentin samples of 21 human deciduous molars.
- Phenotypic heterogeneity analysis using MALDI-TOF-MS and hierarchical clustering at two time points (T(1) and T(2)).
Main Results:
- Thirty-six distinct S. mutans phenotypes were identified.
- Phenotypic heterogeneity significantly increased from 1.4 phenotypes/sample at T(1) to 2.2 phenotypes/sample at T(2).
- Indistinguishable phenotypes were observed within the same teeth and across different teeth of individuals.
Conclusions:
- Restorative treatment significantly increases the phenotypic heterogeneity of Streptococcus mutans in carious dentin.
- This increase is attributed to the adaptation of S. mutans to the altered environment post-caries excavation and restoration.
- Findings highlight the dynamic nature of S. mutans populations in response to dental interventions.
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