Maxillary expansion and stability in the orthodontic-surgical treatment of skeletal anterior open bites.

OBJECTIVES: Evaluation of the surgical/orthodontic treatment's stability using rigid internal fixation.

METHODS AND MATERIALS: Seventeen patients presenting an anterior skeletal openbite, analyzed retrospectively to evaluate stability of surgical-orthodontic treatment using rigid internal fixation: mini plates and screws for maxillary fixation and bicortical screws for the mandible. The surgical procedures were Le Fort I osteotomy and bilateral sagittal split mandibular osteotomy. The patients were classified into 4 groups according to the characteristics described by Ellis (date): Group 1a (n = 4): Class II dental and skeletal malocclusions treated with one piece Le Fort I intrusion osteotomy and bilateral sagittal split mandibular advancement. Group 1 b (n = 4): Class II dental and skeletal malocclusions treated with multisegmental Le Fort I to expand surgically the maxillary width, intrusion osteotomy and bilateral sagittal split mandibular advancement. Group 2a (n = 5): Class III dental and skeletal malocclusions treated with one piece Le Fort I intrusion with/without advancement and bilateral sagittal split mandibular set-back. Group 2b (n = 4): Class III dental and skeletal malocclusions treated with multisegmental Le Fort I, expanding surgically the maxillary width, with/without advancement.