Impact of Silver and Silver-Based Alloys on Human Health. An In Vitro Assessment of Dental Applications

(1) Background: Silver and silver-based alloys are not mutagenic, carcinogenic or toxic to reproduction. However, the European Chemicals Agency (ECHA) has decided to include ionic silver and silver nanoparticles in the list of biocidal substances. In this context, we aimed to evaluate the quantities of silver released and the cytotoxicity of silver-based dental alloys sourced from two distinct suppliers present in the EU (European Union) markets. (2) Methods: Five dental alloys, with silver contents ranging from 9.2% to 58%, were tested by extraction tests in a solution of racemic lactic acid and sodium chloride (7-day extraction at 37°C). The cytotoxic behavior of five other dental alloys with silver contents ranging from 22.4% to 59% was evaluated, as well. (3) Results: Extraction test results indicate small quantities of silver, ranging from 55μg/L to 243μg/L. The assessment of alloys’ cytotoxicity reveals variability of the obtained results; however, none of the tested alloys can be considered cytotoxic. (4) Conclusions: The obtained results indicate that the silver-based alloys included in this study do not pose a risk when used in the oral cavity.