An in vitro evaluation of nickel and chromium release from different commercially available stainless steel crowns

The aim of the present study was to estimate nickel and chromium release from commercially available stainless steel crowns (SSCs) in artificial saliva.

Ten crowns from three manufacturers were immersed in 10 ml of artificial saliva and stored in separate tubes in an incubator at 37°C for 28 days. The crowns were removed from each tube on every 7^th day, and placed in other tubes with fresh artificial saliva. Flame type atomic absorption spectrophotometer was used to check for the release of metal ions in the solution inside each tube at the end of 1, 7, 14, 21, and 28 days and the control samples.

Two-way analysis of variance and pairwise comparison using Bonferroni test was used for statistical analysis. There was statistically verified difference in the release of nickel and chromium on different days in each of the group of SSCs tested. However, no significant difference was seen in the release of both metals among the groups.

In all the SSCs tested, there was the release of nickel and chromium, but the total release of both the metals even at a period of 28 days was below the critical level to cause any toxic effects. Hence, the release of metal ions should not be an alarming concern for the use of any of the group of commercially available SSCs.