A study was carried out on Met- and Leu-enkephalin, Gastrin/CCK-, SP-, CGRP-, NPY-immunoreactive fibers using paraffin sections of dental pulp taken from 8 apparently normal teeth (wisdom teeth or teeth extracted for orthodontic reasons). Within the limitations of the samples studied, dental pulp is characterized by the presence of sensory (Enkephalin-, Gastrin/CCK-immunoreactive) and pain fibers (SP-immunoreactive) and of fibers with a potent vasodilatory action (CGRP-immunoreactive) and by the absence of fibers with a vasoconstrictor action (NPY-immunoreactive).