Estudio cefalométrico de la estabilidad a largo plazo en una muestra con Clase II, división 1ª, tratada con anclaje extraoral y sin extracciones

Zusammenfassung

The long-term stability of the results of treatment of 28 Class II division 1ª patients treated with cervical headgear, fixed edgewise appliance and without extractions is evaluated. Records were taken before treatment (mean age of 10.1 years), after treatment (mean age 13.5 years) and 9.9 years after (final mean age of 22.9 years). Results show the correction of the skeletal Class II during treatment due to the reduction of the ANB angle, which decreased a mean of 1,9 degrees (subsequent to the reduction in the SNA angle and slight increase in the SNB angle), and the reduction of the facial convexity in 2,12 mm. Neither the mandibular plane nor the facial axis showed significant changes. The dental changes show that the inclination of the upper incisor remained unchanged while the inclination of the lower incisor increased 6,71 degrees. During the postreatment period the SNA angle increased signiftcantly 1,28 degrees, but the SNB angle increased 0,92 degrees, so the correction of the Class II malocclusion remained stable. An important residual growth was present and followed a favorable pattem: the facial increased 0,97 degrees, the mandibular plane decreased 2,26 degrees and the gonial angle decreased 2,52 degrees. Considering the teeth, there was relapse in the inclination of the lower incisor. The more it was proclined during treatment the more it moved backwards in the posttreatment period. lt can be concluded that the correction on the skeletal Class II in this sample remains long-term stable.