Addition of silver diamine fluoride to restorative materials: effect on microhardness and microleakage

The purpose of this study was to evaluate the effect of silver diamine fluoride (SDF) on microhardness and microleakage of composite and glass ionomer cement restorations.

Cavities were prepared in 28 extracted teeth and restored according to four regimens (GIC, composite, GIC and SDF conditioned, composite and SDF conditioned). The restored teeth were thermocycled and autoclaved and then exposed to cariogenic challenge (inoculated with Lactobacillus acidophilus and Streptococcus mutans) for 30 days. The restored teeth were sectioned mesio-distally. One half was subjected to microleakage testing (dye penetration using 2% methylene blue) and the other to Vickers hardness test.

Group 4 SDF + Composite had the highest mean microleakage at 1.59 ± 0.02 (mm), and Group 1 (GIC) and Group 3 (Composite) had the lowest mean microleakage (0.63 ± 0.009 mm and 0.63 ± 0.02 mm, respectively). The highest mean microhardness (HV) was observed in Group 3 (Composite) at 327 ± 2.16 and lowest in Group 2 (GIC + SDF) at 283 ± 1.95. Results were statistically significant with a p value < 0.05.

SDF conditioning negatively impacted microhardness and increased microleakage, which could negatively impact the longevity of restorations. Therefore, in this study, SDF was not suitable as a treatment to decrease the occurrence of secondary caries.