RESUMEN
OBJECTIVE: The goal in this study was to evaluate the results of doses of 5 and 15 Gy of radiation in odontogenic region of the rats inferior mandibular-incisors by a histological analysis and the rate of eruptions. DESIGN: Animals were divided into three groups: control, radiotherapy 5 Gy and radiotherapy 15 Gy. In which tooth-eruption-rate was measured every two days. RESULTS: Animals in Group 5 Gy presented values similar to those of the control group. Animals in Group 15 Gy presented reduction in tooth-eruption-rate as of the sixth day of the experiment, vast disorganization of odontoblasts and ameloblasts, apparent reduction in cell population in the follicle region and alterations in cervical loop formation of the dental organ. CONCLUSIONS: It was concluded that there was a difference between the researched doses, and histological alteration at 15 Gy lead to statistical reduction in tooth-eruption-rate.