Preventing dentin erosion with silver diamine fluoride and salivary pellicle: an in vitro study.

OBJECTIVES: To investigate the preventive and discoloring effects of a single and two weekly applications of 38% silver diamine fluoride (SDF) against dentin erosion. MATERIALS AND METHODS: 180 dentin blocks were divided into four groups. Group 1 (SDF2) received two weekly applications of 38% SDF. Group 2 (SDF1) received a single application of 38% SDF. Group 3 (SNF) received a daily application of stannous chloride/amine fluoride/sodium fluoride (standard of care for dental erosion). Group 4 (DW) received a daily application of deionized water. The treated blocks were subjected to a 14-day erosive challenge. Crystal characteristics, elemental composition, surface morphology, percentage of surface microhardness loss (%SMHL), surface loss, and color change (DeltaE) were investigated using X-ray diffraction (XRD), energy-dispersive spectrometry (EDS), scanning electron microscopy (SEM), hardness testing, profilometry, and digital spectrophotometry, respectively. RESULTS: XRD and EDS showed dentin surfaces had silver compounds in SDF2 and SDF1, and stannous chloride in SNF. SEM revealed less dentin demineralization with tubular occlusion in SDF2, SDF1, and SNF, but severe demineralization in DW. The %SMHL of SDF2, SDF1, SNF, and DW were 10.8 +/- 2.1, 15.7 +/- 2.1, 17.9 +/- 2.1, and 28.7 +/- 2.0 (SDF2 < SDF1 < SNF < DW, p < 0.05). Surface loss (microm) of SDF2, SDF1, SNF, and DW were 5.0 +/- 0.6, 6.0 +/- 0.6, 6.0 +/- 0.7, and 9.0 +/- 0.5 (SDF2 < SDF1 = SNF < DW, p < 0.001). DeltaE of SDF2, SDF1, SNF, and DW were 26.0 +/- 3.4, 12.1 +/- 3.8, 6.9 +/- 3.5, and 3.9 +/- 3.6 (SDF2 > SDF1 > SNF = DW, p < 0.001). CONCLUSION: 38% SDF with two weekly applications provided better preventive effects against dentin erosion, but it might discolor dentin. CLINICAL RELEVANCE: The increased 38% SDF application showed a better anti-erosive potential against dentin erosion. However, SDF caused black staining on the dentin.