The present work had the purpose to review the properties actions and uses of eugenol in endodontic, as dressing after pulpectomy. First of all, it was made a spread review of the literature. After that, experiences were proceded in rabbits, instilling in their eyes, variable aumounts of eugenol, to evaluate the irritant powerful of this medicament. At the same time, a clinical research was proceded, putting eugenol within the canal by means of absorbent points, and directly over the pulp stump by inundations of the canal with Luer syrings, with the purpose to observe their sedatives and irritatives properties. Finally, it was made a opinion research between south american endodontists, about the clinic use of eugenol in endodontic. The experiences in laboratory animals showed that eugenol is very irritant to living tissues. Clinically, however, the harmful action of eugenol is practically not perceived, because of their sedatives and anesthetics properties. The endodontists consulted recognize the very high irritant potential of eugenol and were unanimous to proscribe the use of eugenol as dressing after pulpectomy.