The extent of the necrotic lesion in the apical end of the rat incisor pulp seen after Adriamycin administration

Abstract

The extent of the necrotic lesion produced by adriamycin in the apical end of the rat incisor was investigated. Male Sprague Dawley rats were injected intravenously with adriamycin (5 mg/kg body weight), and sacrificed by perfusion with a 2.5% buffered glutaraldehyde solution 1 d after injection. Controls injected with only physiological saline were treated in the same manner. One micron thick plastic serial sections were prepared from the apical end of the incisor, and a schematic representation of the entire lesion as seen in longitudinal section was reproduced from each fiftieth section. Cell destruction was observed for 2.2 mm within the pulp. The lesion extended further incisally in the lingual portion than in the labial portion. The bulbous portion of the odontogenic organ was not affected. This study indicates that the cytotoxicity of adriamycin appears to affect mainly proliferating immature precursor cells within the mesenchyma, and the preodontoblasts.