The arrangement of the blood vessels at the dento-gingival junction was studied in dogs, after perfusion with a carbon-gelalin mixture. In clinically healthy gingivae a plexus of blood vessels was observed close to the crevicular epithelium. This plexus extended under the entire surface of the crevicular epithelium, from the gingival margin to the base of the crevice. In chronically inflamed gingivae the layered arrangement of the blood vessels seen in healthy gingivae was replaced by a vascular bed with loop-like formations.