What type of bacteria predominates in a diseased periodontal pocket?

Correct answer: D. Gram-negative anaerobes

• A. Gram-positive aerobes (Streptococcus, early colonizers) predominate in HEALTHY sulci, not diseased pockets.
• B. Gram-positive anaerobes (Actinomyces, some Peptostreptococcus) are present in early/mild disease but not the predominant pathogenic flora in established deep pockets.
• C. Gram-negative aerobes are not the predominant flora in deep anaerobic periodontal pockets.
• D. Diseased periodontal pockets are dominated by GRAM-NEGATIVE ANAEROBIC bacteria. As pockets deepen, the environment becomes increasingly anaerobic and the flora shifts to pathogenic gram-negative anaerobes. Key periodontal pathogens: Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola (the 'red complex'), Prevotella intermedia, Fusobacterium nucleatum.