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Distraction osteogenesis is a method of enhancing bony deficiencies of the hypoplastic cleft maxilla. Whether it is the result of inherited growth deficiency or of iatrogenic causes from operative intervention, 20 to 25% of cleft maxilla patients require maxillary advancement. Traditionally, this has been done by standard orthognathic surgery at varying LeFort levels. Predictable results have been achieved with standard techniques in minor to moderate maxillary hypoplasia; however, limited advancement and relapse is common in severe cases. Distraction osteogenesis has improved results in these patients by allowing soft tissue relaxation and gradual bone generation. Therefore, greater movement of the craniofacial skeleton is possible in severe cases of maxillary retrusion with lower relapse rates.

Background: External maxillary distractions present additional anesthetic concerns to the existing complexity of the patient with craniofacial disorder. The distraction hardware is rigidly fixed to the cranium and projects in the frontofacial midline, thus limiting oronasal airway access., Methods: A review of 16 patients (10 male, 6 female) having external maxillary distraction was done. Patients with patent tracheostomies were excluded. In all cases, the same type of external distraction device was used (R.E.D., K.L.S. Martin, Jacksonville, FL, USA). Perioperative records were reviewed for medical history; operative diagnosis, presence of airway disease, tracheostomy, laryngoscopy grade, use of fiberoptic bronchoscope, procedure, operative time, use of intraoperative steroid, day of postoperative extubation, and need for reintubation were documented., Results: The study group was subdivided into two diagnostic categories: those with syndromic craniosynostosis (n = 9) and those with cleft lip/palate (CLP) (n = 7). Patients in the craniosynostotic group had grade 1 laryngoscopy views, with the exception of a single patient with Crouzon syndrome who had a grade 3 view. This was the only patient who required fiberoptic intubation. One patient with Apert syndrome required reintubation (48 hours after surgery); successful extubation was done 96 hours later. In the cleft lip/palate group, all patients had grade 1 laryngoscopic views, except one with a grade 3 view; no patient required fiberoptic intubation. Six of the seven patients were extubated immediately after surgery, with one patient extubated the next day. No patient experienced failure of extubation., Conclusions: External maxillary distraction minimally affects anesthetic management provided certain safeguards are observed. The vertical bar can be left attached to the cranial portion of the distractor, or it can be removed for extubation or reintubation. Removal of the vertical bar allows unobstructed direct laryngoscopy. This emphasizes the importance for the emergent availability of the appropriate screwdrivers and wire cutters to remove the vertical bar and trained personnel to perform the removal.

Distraction osteogenesis of the craniofacial skeleton has greatly enhanced traditional osteotomies and bone grafting techniques. The obvious drawbacks to an external distraction device are visibility and awkwardness. A hybrid technique of maxillary distraction for soft tissue expansion and formation of regenerate, combined with rigid internal fixation, is proposed. This technique permits maxillary advancement that may be unattainable by traditional methods and obviates the extended use of external hardware during latency and consolidation of the regenerate. It also allows for optimization of the dental occlusion. The study group was composed of five patients with severe skeletal class III malocclusion who had combined maxillary distraction followed by rigid internal fixation. The average age at the time of LeFort osteotomy was 17 years, with a range of 13 to 19 years. The latency period ranged from 1 to 5 days, and distraction was done at the rate of 1 mm/d in all patients. After the proposed advancement was attained, all patients had reoperation, consisting of distractor removal, optimized interdental relationships with intermaxillary fixation, and placement of rigid internal fixation. The average anterior-posterior maxillary advancement was 11.6 mm, with a range of 10 to 13 mm. Lateral cephalograms and clinical examination showed no relapse at an average follow-up of 25 months, with a range of 5 to 40 months.