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Biological Width — NDEB AFK MCQ

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HardPeriodontologyBiological WidthNDEB AFK

Which of the following correctly defines the biological width (now termed supracrestal tissue attachment)?

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Correct answer: A — Distance from the base of the sulcus to the alveolar bone crest, comprising junctional epithelium and connective tissue attachment

The biological width (supracrestal tissue attachment per the 2017 AAP/EFP classification) is the combined dimension of the junctional epithelium (~0.97 mm) and connective tissue attachment (~1.07 mm), totalling approximately 2.04 mm (Gargiulo et al., 1961). It represents the minimum distance between the base of the sulcus and the alveolar bone crest needed for healthy soft tissue attachment. Restorative margins placed within this zone can cause chronic inflammation and bone loss (biological width violation).

Reference: Newman – Newman and Carranza's Clinical Periodontology, 13th ed., 2019