Estudo comparativo das alterações dentoesqueléticas da má-oclusão de Classe II, 1ª divisão de Angle, nos jovens sem tratamento e nos submetidos a dois tipos de aparelhos ortodônticos

The purpose of this study was to compare the skeletal and dental changes of the Class II, division 1 malocclusions with and without treatment. Seventy five patients were divided in three groups: control, treated with a modified maxillary splint and treated with fixed appliance and Kloehn headgear, each one having thirteen males and twelve females. The cephalometric radiographs were traced and analyzed by means of the "Dentofacial Planner" software. The results showed that there is little change in the pattern of growth and that the anteroinferior facial height increases in the three groups. There is no significant improvement in the maxillomandibular relationship in the control group, while in the treatment groups, the maxilla seemed to be retracted with a significant decrease in the ANB angle. The dentoalveolar changes showed that the appliance used in the second group is efficient in controlling the vertical extrusion of the upper teeth. In both treated groups, they are moved distally, leading to a normal molar relationship and the reduction of the overjet. In the controls, however, the teeth continue to develop in an anteroinferior direction, maintaining the Class II characteristics.