Tooth discoloration induced by endodontic sealers.

Endodontic therapy often results in discoloration of the tooth crown. The main causes are blood, necrotic pulp tissue, and endodontic materials. The staining potentials of various materials were examined in vitro by means of a visual method for tooth color determination. Extracted premolars were prepared, and the following sealers were introduced into the pulp cavities: Zinc oxide eugenol cement, Grossman's cement, AH26, Diaket, N2, Riebler's paste, Tubliseal, and Endomethasone. Before the sealers were applied, the original tooth colors were assessed on the external buccal tooth surfaces. Further color determinations were carried out at regular intervals up to 6 months after introduction of the sealers. Each material induced measurable tooth discoloration within 3 weeks. Riebler's paste caused the most severe discoloration while Diaket caused a mild stain. The other materials produced intermediate discolorations between those of Riebler and Diaket.