When a tooth loses its pulp, it also loses its natural translucency and becomes more opaque. The principal reasons for this change in color of the tooth after treatment of the root canal are due to hemorrhages in the pulp or to the degeneration of the organic tissues. Hemoglobin penetrates the dentin tubules and gives the tooth a pinkish color. If this is associated with an infectious process, the iron from the hemoglobin combined with the hydrogen sulfide produced by the bacteria gives rise to iron sulfide, giving the tooth a characteristic grayish color. The usual treatment indicated for this change in color is dental bleaching (9).