Maxillary transversal deficiency (MTD) is a common skeletal problem. If not treated on time, MTD evolve to a more complex malocclusion. This problem can affect facial growth and development. Rapid maxillary expansion (RME) procedure frequently used for the management. This technique is usually successful in young individuals but as the age advances and the articulations of the maxilla with surrounding facial bones get more rigid, it becomes ineffective. Undesirable side effects or results have been reported after use of RME in skeletally mature patients such as buccal tipping of posterior teeth, extrusion, periodontal tissue recession, fenestration of buccal cortex, necrosis of palatal tissue, failure in opening of midpalatal suture, pain, and relapse of expansion. Side effects of RME are often temporary and permanent damages are rarely seen. The aim of this report is to present the management of a permanent side effect of the RME procedure in a 13-year-old child.