Long-term outcomes of class iii treatment with mandibular cervical headgear followed by fixed appliances

Abstract

To evaluate the stability of the outcomes of mandibular cervical headgear (MCH) andfixed appliance-treated Class III patients at a long-term posttreatment (5 years) observation, comparedwith well-matched untreated Class III controls, following a previous report on the short-termoutcomes of this protocol.Materials and Methods: The treated group consisted of 20 patients with dentoskeletal Class IIImalocclusions treated with a two-phase protocol consisting of MCH and fixed appliances, whilethe control group comprised 18 untreated subjects with similar dentoskeletal Class III malocclusion.Lateral cephalograms of both patients and controls were analyzed at two time points: posttreatment(PT), after two-phase treatment; and long term (LT). All patients were at a postpubertalstage of skeletal maturity at PT, and they showed CS6 at LT, thus revealing completion of pubertalcraniofacial growth.Results: In the long term, the treatment group showed significantly smaller values for mandibularlength (Co-Gn), SNB angle, maxillomandibular differential, and molar relation. When comparedwith the controls, the treated patients exhibited also greater values for ANB angle, Wits appraisal,and overjet at LT. No significant difference between the two groups was found for the changesoccurring from PT to LT.Conclusions: Favorable dentoskeletal outcomes induced by MCH and fixed appliances remainedstable in the long term; untreated Class III malocclusion did not show any tendency toward selfimprovementduring the postpubertal interval. (Angle Orthod. 2009;79:828-834. © 2009 by The EH Angle Education and Research Foundation, Inc.