RESUMO
A modified removable appliance for molar distalization called C-activator was used in a 10-year old male patient with a Class II anterior deep bite malocclusion with upper arch discrepancy. The treatment plan involved correcting the Class II relationship, distalizing both upper first molars, and regaining space for the erupting canines. The C-activator, which was used for 6 months, consisted of a labial framework formed from .036-in stainless steel wire and an acrylic monobloc. Both the closed helices of the labial framework were compressed for reactivation during the C-activator treatment period. C-activator mechanics simultaneously achieved distalization of the upper first molars into their proper positions and repositioning of the mandible. After 21 months of treatment, the correct overbite and overjet was obtained and contributed to an improvement in facial balance. The treatment results were stable 6 months after debonding. Fabrication and placement of the new appliance and clinical procedures are detailed, and the treatment sequence and results of this case are presented as follows.