Early mixed dentition treatment: postretention evaluation of stability and relapse.

Twenty-five patients who underwent early mixed dentition treatment were evaluated during the following stages: pretreatment (early mixed dentition), phase 2 (early permanent dentition), and postretention (average of 9.5 years). All patients were treated with a removable passive lingual arch. The mandibular incisors were judged to have satisfactory alignment at phase 2 evaluation and had no further orthodontic treatment. Nineteen of 25 cases (76%) demonstrated clinically satisfactory mandibular alignment postretention. Intercanine width decreased in 72% of the cases postretention and arch length decreased in 100% postretention. Intermolar width increased in 18 of 25 (72%) of the cases during treatment and remained stable in 17 of 25 (68%) of the cases. No predictors or associations could be found to help clinicians in determining the long-term prognosis of dental stability.