The effect of MPG on radiation-induced odontogenic tissue metaplasia

This investigation monitored the effect of 2-mercaptopropionylglycine (MPG) in reducing radiation damage to the tooth-forming tissues. Fifty rats were exposed to x-ray doses of between 3 and 19 Gy directed toward the maxillary incisor germinal centers. Half of the animals were given an injection of MPG before irradiation, while the other rats were injected with saline solution. Administration of MPG did not significantly reduce the frequency of dentinal niche formation relative to the control teeth. The average lengths and percentage depths of the apicoincisal niches were statistically smaller in the groups treated with MPG. Although statistically significant, the mild protective effect of MPG was not clinically important because damage to the irradiated teeth was still extensive.