LAUSR

BACKGROUND Palatal expansion treatment has been used to expand the constricted maxillary arch and has become a routine procedure in orthodontic practice over the past decades. However, the long-term stability of expansion in the permanent dentition without a surgical approach is uncertain. CASE SUMMARY We present the case of a 15-year-old boy with Class II malocclusion and constricted arches. The patient was treated with rapid palatal expansion (RPE) followed by a fixed orthodontic appliance. A 7-year follow-up evaluation was performed by analyzing cephalometric radiographs, plaster models, and photographs. The patient’s constricted maxillary and mandibular arches were relived after the expansion treatment. A Class I occlusion and normal arch form were established and maintained in the long-term. CONCLUSION RPE treatment is successful in solving constricted dental arch in the permanent dentition without a surgical approach. Permanent retention and even occlusal contact help prevent long-term relapse.