Tracing genotypes of mutans streptococci on tooth sites by random amplified polymorphic DNA (RAPD) analysis.

Area of Science:

• Oral microbiology
• Dental research
• Infectious disease

Background:

• Mutans streptococci are key etiological agents in dental caries.
• Understanding their distribution and persistence is crucial for targeted prevention strategies.
• Previous research has focused on overall prevalence, but site-specific colonization patterns require further investigation.

Purpose of the Study:

• To investigate the distribution and persistence of mutans streptococci genotypes across different tooth sites within the same oral cavity.
• To determine the stability of these genotypes over time (4-7 months).
• To explore interindividual variations in genotype colonization.

Main Methods:

• Plaque samples collected from four specific tooth sites in 13 adults (aged 20-40).
• Samples analyzed using Polymerase Chain Reaction (PCR) for species identification and Random Amplified Polymorphic DNA (RAPD) analysis for genotyping.
• Restriction Endonuclease Analysis (REA) used for confirmation.
• Sampling conducted on two occasions, 4-7 months apart.

Main Results:

• Mutans streptococci were detected at multiple tooth sites within individuals.
• The same genotypes were frequently found on different sites within the same mouth.
• Genotypes demonstrated persistence at specific sites for up to 4-7 months.
• Significant interindividual differences in genotype occurrence were observed, with up to seven genotypes per individual.

Conclusions:

• Multiple mutans streptococci genotypes can co-colonize a single tooth site.
• The same genotype can colonize multiple sites within an individual's oral cavity.
• Genotypes exhibit considerable persistence, indicating long-term colonization potential.
• Findings highlight the complex dynamics of mutans streptococci colonization and persistence in the human mouth.