Effect of silver diamine fluoride on precipitated silver compounds and resin–dentin bond properties

This study aimed to evaluate how three silver diamine fluoride (SDF) treatments-38% SDF, 3.8% SDF, and SDF combined with potassium iodide (SDF/KI)-affect resin-dentin bond strength, dentin microhardness, and silver compound deposition. Bovine root dentin was treated with each solution and analyzed using micro-tensile bond testing, Vickers hardness, scanning electron microscopy (SEM), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and X-ray absorption near edge structure (XANES) analysis. The 38% SDF group showed significantly reduced bond strength due to superficial silver deposition, which was restored by removing a 0.1 mm dentin layer after one week. In contrast, the 3.8% SDF and SDF/KI groups maintained bond strength and showed minimal silver accumulation. The XANES confirmed the presence of silver iodide (AgI) in the SDF/KI group. These findings suggest that superficial dentin removal after 38% SDF treatment, or the use of diluted (3.8%) or modified (SDF/KI) SDF, may preserve bonding performance while retaining caries-arresting effects.