STAINING OF LIPIDS IN HUMAN DENTINE MATRIX

Undecalcified ground sections of dentine were treated with 0.02 per cent acetic acid, then stained using one of a series of methods for lipids. The stains were located in the peritubular matrix in certain clearly defined zones of the dentine. Four zones were differentiated: from the pulp outwards these were the unstained predentine, an unstained second zone, a third zone in which the peritubular dentine matrix was heavily stained, and at the periphery of the dentine a fourth zone which was unstained. In radicular dentine, zone three was gradually reduced in size towards the apex of the tooth, not being observed in the apical third of the root. The results obtained suggest that the lipids present are lecithins. © 1968.