Effect of Ammonia-Free Silver Fluoride and Silver Diammine Fluoride on Immediate Microshear Bond Strength of Resin-Modified Glass Ionomer to Demineralised Primary Tooth Dentine Publisher Pubmed

Summary: Does silver fluoride (SF) affect bond strength in dental restoration? A study suggests it compromises adhesion in primary teeth, unlike silver diammine fluoride (SDF). Should we rethink our protocols? #Dentistry #DentalResearch

Abedinzade Zare A ; Vafadar M ; Behroozibakhsh M ; Hashemian A ; Lari M ; Abtahi S
Source: European Archives of Paediatric Dentistry Published:2026

Abstract

Purpose: This study aimed to compare the effect of water-based ammonia-free silver fluoride (SF) and silver diammine fluoride (SDF) on the microshear bond strength (MSBS) of resin-modified glass ionomer (RMGIC) to artificially demineralised primary tooth dentine. Methods: Twenty-four extracted primary molars were prepared to expose mid-coronal dentine; two bonding sites per tooth (total = 48 specimens) were chemically demineralised (pH 4.8) to simulate active caries. Specimens were randomised into three groups (n = 16): SF (Riva Star Aqua), SDF (Cariestop 30%), and Control (distilled water). RMGIC (Riva Light Cure HV) was bonded and stored for 24 h at 37 °C. MSBS was measured using a universal testing machine, and failure modes were analysed using a stereomicroscope. Data were analysed using one-way ANOVA with Tamhane's T2 post hoc test (α = 0.05). Results: The SF group exhibited significantly lower bond strength (3.65 ± 1.80 MPa) than the Control (6.86 ± 3.15 MPa, p < 0.01) and SDF groups (6.65 ± 4.80 MPa, p < 0.05). No significant difference was found between SDF and Control (p > 0.05); however, the SDF group demonstrated greater variability, consistent with Weibull analysis. Adhesive failure predominated across all groups, with SDF showing more mixed failures. Conclusion: Water-based SF significantly compromised RMGIC adhesion to demineralised primary tooth dentine. SDF maintained comparable mean bond strength to the control but with higher variability. Ammonia-free SF formulations may reduce immediate RMGIC retention when used before restoration, and this interaction may warrant protocol optimisation in SMART-based applications. © The Author(s) 2026.