Abstract
Three-dimensional observations of the vascular system of molar pulps in adult crab-eating monkeys were examined by light, transmission and scanning electron microscopy. The pulp tissue was reduced in size by secondary dentin formation which caused bifurcated roots on the mesial side of the radicular chamber in the mandibular first molar. As a result, the arrangement of blood vessels could be divided into two parts. Capillary networks were relatively rich in the pulp horn and peripheral side of the coronal chamber, while in the radicular pulp the capillary network was relatively sparse. Transmission electron microscopy revealed that small nerve fibers were closely associated with the arterioles of various sizes. Nerve fibers containing small clear vesicles and a few large and small dense-cored vesicles were observed near the arterioles, and the nerve terminals were considered to be adrenergic. These complex features observed in this study are thought to be related to the regulation of the local blood flow in the monkey molar pulp.
