Abstract
Patients with cleft lip and palate （CLP） often present relative skeletal mandibular prognathism. The main reason for this is the scars from lip and palatoplasty which inhibit maxillary anterior growth. The amount of forward movement of the entire maxilla by Le Fort Ⅰ osteotomy is limited to preserve the velopharyngeal function, making it difficult to achieve the ideal forward movement of the maxilla. If velopharyngeal insufficiency occurs after an ideal forward movement, pharyngoplasty is required. Because MASDO does not move the soft palate forward and does not affect the phonetic function, it is still one of the commonly used orthognathic procedures in applicable CLP cases.
In this study, we performed MASDO on a patient with inferior maxillary growth and severe crowding due to a cleft palate with good results. The patient was a phase-2 16-year-7-month-old male with a total cross bite and skeletal class Ⅲ with midfacial deficiency. In preoperative orthodontic treatment, the bilateral upper first premolars were extracted to gain space to improve the severe crowding in the maxillary dentition, and the mandible was aligned with non-extraction because of the spaced arch.
As a result of MASDO, the midfacial deficiency was improved without affecting the velopharyngeal function, and a good lateral profile was obtained. In addition, the dental arch length was enlarged, the severe anterior crowding was eliminated, and the maxillary second molars were able to be aligned. In order to align the dental midline with the facial midline, an orthodontic anchoring screw was inserted in the left molar region as a fixation source. After 2 years of retention, the width diameter of the maxillary dentition was slightly reduced, but the occlusion was stable and the facial appearance was preserved.
