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PubMed · 9773990

Rigid external distraction: its application in cleft maxillary deformities.

Abstract

Patients with severe maxillary hypoplasia secondary to congenital facial clefting present numerous challenging problems for the reconstructive surgeon. Traditional surgical/orthodontic approaches for these patients often fall short of expectations, especially for achieving normal facial aesthetics and proportions. The purpose of this paper is to present our clinical experience and cephalometric results with the use of rigid external distraction for the treatment of patients with severe maxillary deficiency. Eighteen consecutive orofacial cleft patients with severe maxillary hypoplasia were treated with maxillary distraction osteogenesis. Criteria for patient selection included severe maxillary hypoplasia with negative overjet of 8 mm or greater, patients with normal mandibular morphology, and patients with full primary dentition or older. There were 10 unilateral cleft lip and palate patients, 6 bilateral cleft lip and palate patients, and 2 patients with severe congenital facial clefting. A maxillary splint was prepared for each patient, and all patients underwent a high Le Fort I maxillary osteotomy. All surgery was performed on either an outpatient or a 23-hour admission basis. No patient required blood transfusions or intermaxillary fixation. Two types of mechanical distraction were utilized in this series. In group 1 (n = 14), the patients underwent rigid external distraction with an external distraction device. In group 2 (n = 4), patients underwent face mask distraction with elastics. There was no surgical morbidity in any of the patients. For the patients in the rigid external distraction group, the mean effective horizontal advancement of the maxilla was 11.7 mm. All of these patients had correction of their negative overjet. For patients in the face mask distraction group, the results were disappointing. The mean effective advancement of the maxilla in this group was only 5.2 mm. In all face mask distraction patients, the initial maxillary hypoplasia was undercorrected. Maxillary distraction osteogenesis with rigid external distraction permits full correction of the midfacial deficiency, including both the skeletal and soft-tissue deficiencies. Rigid external distraction in patients with severe maxillary hypoplasia allows full correction of the deformity through treatment of the affected region only. It offers the distinct advantage of correcting these severe deformities through a minimal procedure. Rigid external distraction has dramatically improved our treatment results for patients with severe cleft maxillary hypoplasia.

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BibTeXRIS

J W Polley, A A Figueroa. 1998. Rigid external distraction: its application in cleft maxillary deformities.. https://pubmed.ncbi.nlm.nih.gov/9773990/

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