Micro & Immunology · patient case question
How is the microbiological picture in this condition best characterized?
Patient case: Rapid attachment loss in a young adult
Patient: 26-year-old patient.
Chief complaint: Gums bleed and some teeth feel loose.
History: Non-smoker, no systemic disease. A sibling lost teeth young.
Findings: Radiographs show bone loss disproportionate to the visible plaque, with only light calculus on posterior teeth. Perio charting shows 4 to 5 mm pockets on almost all teeth with bleeding on probing. Clinically, heavy calculus is present on the anterior teeth. Working diagnosis: aggressive (Grade C) periodontitis.
Show answer and explanation
Correct answer: B. Three or more strictly anaerobic species
- A. Deep pockets are anaerobic environments. Strict aerobes cannot survive there.
- B. CORRECT. The subgingival flora in aggressive periodontitis is POLYMICROBIAL and dominated by strict anaerobes — Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia and Treponema denticola — alongside Aggregatibacter actinomycetemcomitans. No single organism accounts for the disease.
- C. A. actinomycetemcomitans is strongly associated with localized aggressive periodontitis, but it acts within a polymicrobial community rather than alone.
- D. Periodontal disease is not a monomicrobial infection. Isolating one species does not explain the destruction.
Practice Micro & Immunology questions Micro & Immunology study notes