Evaluation of chemical protection against radiogenic osteodentin synthesis

The effect of the radioprotector 2-mercaptopropionylglycine (MPG) in preventing the synthesis of radiation-induced osteodentin was examined. Fifty rats were exposed to single x-ray doses of between 3 and 19 Gy localized to the maxillary incisor growth centers. Half of the animals received an injection of MPG before irradiation while saline was administered to the other rats. MPG produced statistically significant reductions in the severity of osteodentin generation, but not its frequency, at some radiation levels. The nature of osteodentin and possible mechanisms of chemical radioprotection by MPG are discussed.