Effects of silver diamine fluoride in human dentin: A systematic review of in vitro studies

The aim of this systematic review was to investigate the effects of silver diamine fluoride (SDF) on dentin in permanent teeth. Eight databases (PubMed, SciELO, Scopus, EMBASE, Web of Science, Science Direct, LILACS, and Livivo) and three "gray literature" sources (Open Access Theses and Dissertations [OATD], Open Grey, and ProQuest) were used. Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were followed, and methodology quality was assessed using the QUIN tool. The review included in vitro studies investigating the effect of 38% SDF on demineralized permanent dentin. The primary outcomes were findings from energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) approaches, while secondary outcomes included findings from hardness testing, micro-computed tomography (micro-CT), and scanning electron microscopy. From 16,630 results, 17 studies met the eligibility criteria. After treatment with 38% SDF, significant increases were observed in the levels of calcium (Ca) and phosphorus (P) in dentin. Higher mineral/matrix ratios and a significantly lower amide I/HPO^2- ratio were identified, using FITR, in groups treated with SDF. Restoration of dentin crystallinity in groups treated with SDF, with sharp peaks for silver chloride and silver, were shown using XRD. Micro-computed tomography revealed reduced lesion depth, while scanning electron microscopy showed smoother surfaces and partial occlusion of tubules. Risk of bias was moderate in 13 studies and high in four. Overall, 38% SDF reduces demineralization, preserves mineral content, increases the levels of Ca and P, and enhances mineral/matrix ratios, demonstrating potential for managing demineralization.