Caries Pathogenesis — NDEB AFK MCQ

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EasyCommunity Dentistry & EpidemiologyCaries PathogenesisNDEB AFK

Which acid in dental plaque is the primary cause of enamel demineralisation in the caries process?

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Correct answer: A — Lactic acid

Lactic acid is the primary organic acid produced by cariogenic bacteria (Streptococcus mutans, Lactobacillus) through anaerobic fermentation of dietary carbohydrates. It is the most abundant acid in dental plaque and the principal driver of the pH drop below the critical pH (approximately 5.5 for enamel) that initiates demineralisation. Other acids (acetic, propionic, formic) contribute but lactic acid is predominant.

Reference: Fejerskov & Kidd – Dental Caries: The Disease and Its Clinical Management, 3rd ed., 2015