Methods: In this in vivo study, biocompatibility was evaluated on subcutaneous tissue of rats. The test materials were inserted into subcutaneous of two groups of 20, and histopathological examinations were done 7 and 30 days after the implantation. In each time period, 10 test cases and 1 negative control were used and inflammation was evaluated using conventional transmitted light microscopy. The results of the inflammatory reactions were tested with Mann–Whitney U-Test, Wilcoxon Signed Ranks Test, Fisher Exact Test, and Mc Nemar Test.
Results: In 7 days period, inflammation induced by nanosilver coated gutta-percha was significantly more than normal gutta-percha (P<0.001). After 30 days, inflammation response of two test groups were significantly different (P<0.001). There was no sign of inflammation in normal gutta-percha group, whereas mild inflammation was reported in test cases associated with nanosilver coated gutta-percha. In both time periods formation of collagenized-fibrous tissue was observed.
Conclusions: Considering the fact that inflammation response decreased in both test groups, and after 30 days in test cases associated with silver coated gutta-percha mild inflammation was present, and also the presence of collagenized-fibrous tissue in both groups which is a sign of healing, it can be concluded that there is no contraindication in clinical usage of nanosilver coated gutta-percha.