Estudo da reabsor？？o radicular apical após o uso de aparelho extrabucal no tratamento da má oclus？o do tipo Classe II, 1a divis？o dentária

aim: the aim of this study was to verify the effect of occipital headgear wear on the intensity of apical root resorption of the upper first permanent molars submitted to the action of the appliance. methods: were evaluated periapical x-rays of 19 leucoderms young female - with ages between 8 and 10 years, with dental class ii, division 1 malocclusion, before and after orthodontic treatment, using high-pull headgear. the 76 x-rays were divided into two groups according to their root formation. group a consisted of 18 x-rays with incomplete root formation, except for the palatine root, before treatment and 18 after treatment. group b consisted of 20 x-rays where root formation was completed before treatment and 20 after treatment. the root lengths were measured with digital caliper and the registered measures were submitted to the error of the method and statistical analysis, student t test, to verify the differences regarding the root length before and after the treatment with occipital headgear. results: in group a, there was a significant increase of the root lengths, while in the group b the differences were not significant. posttreatment group a showed no significant differences with the mean root lengths of pretreatment group b, in other words, teeth with incomplete root formation at onset of orthodontic treatment presented normal root growth during the active treatment. conclusion: therefore, it was concluded that high-pull headgear didn't influence negatively in the root formation and it didn't provoke apical resorption of the molars submitted to the action of the appliance, suggesting that occipital headgear doesn't present risks to the root structure and formation when correctly indicated and applied.