THE ISOLATION OF A MELANIN-LIKE SUBSTANCE FROM CARIOUS ORGANIC MATRIX OF HUMAN DENTIN

¹ Department of Biochemistry and Pharmacology, School of Medicine and Dentistry, University of Rochester, Rochester, New York

Hydrolysis of carious organic matrix of teeth in 20 per cent HCl at 110°C. for 24 hours yielded 3.78 per cent of a black, insoluble pigment. Elemental analyses showed that it contained on the average 69.51 per cent carbon, 8.31 per cent hydrogen, 5.06 per cent nitrogen, and 17.91 per cent oxygen. When compared with analyses of melanins similarly prepared from other sources, these values indicate that the pigment obtained is a melanin.

No insoluble pigment could be obtained from noncarious matrix.

From both carious and noncarious dentinal matrix some soluble pigment was obtained, the amount being considerably greater in the carious. This form was not studied further.