A 14-year-old boy presented with a severe open-bite and arch collapse associated with muscular disease. Multiple osteotomies of the maxilla and mandible with autogenous bone grafting were used for surgical closure of the open-bite. A satisfactory and stable skeletal result was achieved. The patient was then referred for orthodontic therapy to achieve a better dental interdigitation and maintenance of the newly created relationship. In severe cases of open-bite multiple osteotomies of the mandible and maxilla may need to be performed in order to accomplish the desired results. These same results may not be ach ieved by any single surgical procedure. The relationship between severe open-bite and muscle diseases needs to be further established. Once these etiologic factors are known, steps could perhaps be taken to alter the maldevelopment of the facial skeleton. Until this happens, the symptoms are best treated by a combination of surgical and orthodontic intervention.