Dense-cored vesicles in human dental macrophage-like pulpal cells

In the human dental pulp of five healthy premolars, we detected the presence of vesicles in the cytoplasm of macrophage-like cells. There were, in general, two types of vesicles, with regard to their size and content. The first was of smaller size (35 to 55 nm), and they were electron optically empty. The second type included larger vesicles (100 to 150 nm) presenting a heavily and homogeneously osmiophilic dense core. Their overall morphology was strikingly similar to the well-known, dense-cored vesicles of the sympathetic and neuroendocrine systems. This morphological evidence may be considered as an adjunctive support for the neural crest derivation of the dental pulp.