Long-term outcome in a patient with Class I malocclusion with severe crowding treated without extractions.

The treatment of a patient with a Class I malocclusion with significant skeletal transverse maxillary discrepancy and severe crowding is presented. The maxilla was narrow compared with the mandible, and the posterior teeth were compensated, with the maxillary teeth inclined buccally and the mandibular teeth inclined lingually. Treatment included rapid palatal expansion to correct the transverse maxillary deficiency and to gain arch length. Long-term follow-up (20 years) with a stable result is reported.