An Acquired Pigmented Pellicle of the Enamel Surface

Abstract

The data concerned with the study of the pellicle''s brown pigment do not give any definite indication of its nature. Porphyrin and hematin pigments have been eliminated. The possibility of the presence of inorganic salts of Pb and Fe also appears remote, because of the insolubility of the pigmented matter. This property is more suggestive of a melanin-like substance.