ESTUDO COMPARATIVO DOS EFEITOS DENTOESQUELÉTICOS DOS APARELHOS TWIN BLOCK E ATIVADOR ABERTO ELÁSTICO DE KLAMMT NO TRATAMENTO DA CLASSE II

Abstract

This study was done by using cephalometric radiographs in profile, in order to determine the effects dentoskeletal of three groups. Two groups consisting of fifteen patients class II malocclusion, Division 1, treated with Twin Block appliance and Elastic Open Activator of Klammt, and a third group of twenty-five pacients who have not gone trought any orthodontic treatment, called control group. The groups had a mean age of 11.4 years, 10.45 and 10.92 respectively at the beginning of treatment and 12.25, 11.93 and 12.12 respectively at the end of treatment. There were two cephalometric radiographs side of face) for each pacient, at the beginning and at the end of each treatment. The comparison of compatibility between the groups regarding age, and the beginning and end time of treatment was performed by ANOVA. To check the compatibility between the groups regarding gender distribution, we applied the chi-square test. The intergroup comparison of cephalometric variables in the initial stages (T1), end (T2) and alterations with treatment (T2-1) was performed using the nonparametric Kruskal-Wallis and Dunn's test, showed of a significant result, to specify in which groups there was a difference. The study showed that the Twin Block appliances and Klammt did not promote changes in maxillary development, and promoted an increase in the effective length, and body of the mandible (lower jaw). The maxillomandibular relation improved significantly in the treated groups compared to the control group. The dentoalveolar alterations showed that the upper incisors showed no significant changes when comparing experimental groups to control group. The Lower dentoalveolar changes showed a vestibularisation and protrusion, statistically significant in the experimental group treated with Twin Block when compared to the control group, and no significance when compared to the group treated with Klammt activator . The group treated with Klammt only showed the variable 1-AP with a significant result when compared to the control group, showing however a relation of protrusion of the lower incisors. As regards to dental relations, the overjet showed a statistically significant reduction in the experimental groups, during the period evaluated, the relation between the antero-posterior molars also showed a statistically significant reduction in the groups treated with Klammt activator and Twin Block. In the soft tissue profile was not observed a significant differences between groups regarding the variables Li-E and ANL, but the variable Ls-E showed that the Twin Block caused a retrusion on upper lip when compared to the control group, and when compared to the Klammt group did not obtained statistical significance.