Irradiation injury of the dental pulp after theurapeutic doses of γ-radiation.Experimental study in rats

Hippokratia 2002, 6(3):137-141

S. Stefanidis, A. Ginalis, M. Dermenjopoulou, M. Kannelaki-Kyparissi


The aim of this experimental study was to evaluate the microscopic alterations in normal dental pulps, associated with therapeutic doses of gamma irradiation. Sixteen adult male Wistar rats were irradiated in the mandibular region with a single dose of 2.000 cGy from a Co-60 source. Groups of two were sacrificed 15, 20, 25, 30, 45, 60, 75, and 90 days after irradiation. Dental pulps from incisor teeth were removed and fixed in formaldehyde solution and sections were stained with Eosine – Hematoxyline and Gomori techniques. The following histological alterations were observed: 1) Edema in the connective tissue of the pulp and around the blood vessels. 2) Progressively established narrowing of pulp vessels’ lumen because of thickening of their wall, observed after the 25th day. 3) Obstruction of the lumen in a significant proportion of vessels, after the 75th day. 4) Appearance of newly developed capillaries, mainly at the periphery of the pulp, observed after the 25th day. 5) The amount of the connective tissue cells and reticular fibers of the pulp was obiously increased after the 45th day. 6) Foamy degeneration of the cytoplasm in the outer region of the odontoblasts.