Development of an Impression Material with Antimicrobial Properties for Dental Application

To evaluate the antimicrobial activity and physico-mechanical properties of an irreversible hydrocolloid in which nanostructured silver vanadate decorated with silver nanoparticles (AgVO₃ ) was added at various concentrations (0% - control, 2.5%, 5%, and 10% by weight).

The agar diffusion method (n = 10) was used to evaluate the inhibitory effect on the following species: Streptococcus mutans, Staphyloccocus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. The gelation time, flow capacity and plastic deformation were verified (n = 10). The data were analyzed using the Kruskal-Wallis test followed by the Dunn post-test, or via one-way ANOVA with multiple comparisons with a Bonferroni adjustment depending on the distribution (α = 0.05).

All percentages of the nanomaterial were able to promote the antimicrobial activity of a hydrocolloid, with the formation of an inhibition zone (p < 0.05). In general, there was a dose-dependent effect on antimicrobial activity: higher concentrations of the nanomaterial promoted greater action except in the cases of P. aeruginosa (p < 0.001; F = 51.74) and S. aureus (p < 0.001), where the highest inhibition was for the 2.5% group. No difference was found in the gelation time when the control was compared with the groups with AgVO₃ (p > 0.05). The difference was between the 5% and 10% groups (p = 0.007), and the latter promoted an increase in time. The flow capacity of the hydrocolloid with 5% of AgVO₃ was significantly lower when compared with the control (p = 0.034). The AgVO₃ influenced the plastic deformation (p < 0.001) in such a way that concentrations of 5% (p = 0.010) and 10% (p < 0.001) promoted an increase in this property when compared with the control.

AgVO₃ can be incorporated into an irreversible hydrocolloid as an antimicrobial agent without promoting adverse effects on physical-mechanical properties when used in concentrations of 2.5%.