Which property BEST describes the retention of silver diamine fluoride on the tooth surface?

Correct answer: C. Substantivity

• A. Osteoinduction refers to inducing new bone formation, which is unrelated to SDF.
• B. Chelation describes binding metal ions — the mechanism of EDTA in endodontics, not the retention of SDF.
• C. CORRECT. SUBSTANTIVITY is the ability of an agent to bind to oral surfaces and be released over time, giving prolonged action beyond the moment of application — the same property that makes chlorhexidine effective. SDF binds to hydroxyapatite and dentin collagen, and the silver is retained in the lesion where it exerts sustained antibacterial action while the fluoride promotes remineralization and forms an acid-resistant, occluded surface layer.
• D. Dentin bridge formation is what calcium hydroxide and MTA induce in pulp capping — SDF is not a pulp capping agent.

Note: ⚠️ Contested item — SDF is also legitimately described as bactericidal and as forming silver phosphate and calcium fluoride. 'Substantivity' is the term that captures its sustained retention. Discuss with the group. Note SDF permanently BLACK-STAINS arrested lesions — always consent for this.