Cytotoxicity of eugenol in sealer containing zinc-oxide.

In this study two zinc-oxide-based root canal sealers were compared for their tissue toxic response. The sealers tested were zinc-oxide eugenol and zinc-oxide glycerine. Fifteen albino rats were used for the study and were injected subcutaneously in the preset state. The tissue response was assessed by counting the polymorphonuclear cells at Day 1, Day 7 and Day 15 of the study period. The inflammatory response was graded according to the mean polymorphonuclear counts in the five rats for each period. The results showed that the toxicity was greater for the eugenol-containing sealer and increased during the three time intervals. For the non-eugenol sealer the response was milder and reached a peak by 7 days after which it decreased.