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Published on: July 4, 2018
Microbial flora in orodental infections
1Department of Microbiology, Pt. BD Sharma Post Graduate Institute of Medical Sciences, Rohtak, Haryana - 124 001, India.
Indian Journal of Medical Microbiology
|July 24, 2007
Summary
This study compared oral bacterial flora in healthy individuals versus those with dental caries, gingivitis, and periodontitis. Results show a decreased aerobic to anaerobic bacteria ratio in disease states, indicating significant microbial shifts.
Area of Science:
- Microbiology
- Oral Health
- Bacteriology
Background:
- The oral cavity harbors a complex microbial ecosystem.
- Imbalances in this flora are linked to various oral diseases.
Purpose of the Study:
- To compare aerobic and anaerobic bacterial oral flora in healthy individuals versus those with dental caries, gingivitis, and adult periodontitis.
- To identify specific microbial shifts associated with these conditions.
Main Methods:
- Bacterial samples were collected from control (healthy) and study groups (dental caries, gingivitis, periodontitis).
- Aerobic and anaerobic bacterial populations were quantified and their ratio analyzed.
- Microbial composition was compared across different oral conditions.
Main Results:
- All samples yielded microbes; however, the aerobic to anaerobic bacteria ratio was significantly higher in normal flora (1.48) compared to dental caries (0.9), gingivitis (0.72), and periodontitis (0.56).
- Orodental infections were polymicrobial in 97% of cases, with 84% of the study group having three or more microbes compared to 28% in controls.
- Specific bacteria were associated with different conditions: Streptococcus mutans and anaerobic lactobacilli in caries; Actinomyces and Peptostreptococcus spp. in gingivitis; Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in periodontitis.
Conclusions:
- A reduced aerobic to anaerobic bacteria ratio is indicative of oral disease states.
- Polymicrobial infections are prevalent in dental caries, gingivitis, and periodontitis.
- Distinct bacterial profiles characterize different oral pathologies, aiding in diagnosis and targeted treatment.
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