Le Fort III Distraction With Internal vs External Distractors: A Cephalometric Analysis.

OBJECTIVE: This study compares the change in midface position following Le Fort III advancement using either rigid external distraction (group 1) or internal distraction (group 2). We hypothesized that, with reference to right-facing cephalometry, internal distraction would result in increased clockwise rotation and inferior displacement of the midface. DESIGN: Le Fort III osteotomies and standardized distraction protocols were performed on 10 cadaveric specimens per group. Right-facing lateral cephalograms were traced and compared across time points to determine change in position at points orbitale, anterior nasal spine (ANS), A-point, and angle ANB. SETTING: Institutional. PATIENTS, PARTICIPANTS: Twenty cadaveric head specimens. INTERVENTIONS: Standard subcranial Le Fort III osteotomies were performed from a coronal approach and adequately mobilized. The specified distraction mechanism was applied and advanced by 15 mm. MAIN OUTCOME MEASURE(S): Changes of position were calculated at various skeletal landmarks: orbitale, ANS, A-point, and ANB. RESULTS: Group 1 demonstrated relatively uniform x-axis advancement with minimal inferior repositioning at the A-point, ANS, and orbitale. Group 2 demonstrated marked variation in x-axis advancement among the 3 points, along with a significant inferior repositioning and clockwise rotation of the midface ( P < .0001). CONCLUSION: External distraction resulted in more uniform advancement of the midface, whereas internal distraction resulted in greater clockwise rotation and inferior displacement. External distraction appears to provide increased vector control of the midface, which is important in creating a customized distraction plan based on the patient's individual occlusal and skeletal needs.

Management of post midface distraction occlusal discrepancy using temporary anchorage devices in a cleft patient.

Open bite deformity following a successful midface advancement by distraction osteogenesis is a common complication. Temporary anchorage devices can be deployed during the distraction and post-distraction settling phases for restoring the occlusion even in severe cases. The following report describes the management of severe anterior open bite following maxillary distraction.

Changes in mandibular position during midface distraction in patients with syndromic craniosynostosis.

The purpose of this study was to evaluate changes in mandibular position during midface distraction. Midface distraction was performed in patients with syndromic craniosynostosis to increase upper airway volume. Although this treatment resulted in changes in occlusion, the concomitant changes in mandibular position were poorly understood. In this retrospective study, three-dimensional (3D) cephalograms were obtained before and after midface distraction in 15 patients with syndromic craniosynostosis. Perioperative polysomnography scores and changes in maxillary and mandibular position, mandibular volume, and upper airway volume were analyzed. Results showed a significant improvement in apnea-hypopnea index (AHI) (from 20.6 ± 21.3 to 6.9 ± 5.1, p < 0.05) and upper airway volume (from 2951.65 ± 2286.38 to 5218.04 ± 3150.05 mm3, p < 0.001). When the lowest point of the sella turcica was set as the reference point, the mandible moved significantly in an anterior direction (from 47.9 ± 11.5 to 51.9 ± 9.8 mm, p < 0.05). Mandibular volume did not change significantly perioperatively (from 32530.19 ± 10726.01 to 35590.50 ± 14879.21 mm3, p = 0.10). There were positive correlations between the rates of improvement in AHI and the amount of mandibular movement in the anterior and inferior directions (both p < 0.05). Within the limitations of the study, it seems that the mandible moved in the anterior-inferior direction after midface distraction, and the amount of movement correlated with improvement in respiratory function. Therefore, it is important to consider the position of the mandible when determining the direction of midface distraction, as it may influence the therapeutic effect.

Fronto-orbito-nasal advancement a surgical approach based on skull development in treatment of craniofacial deformities.

The classical treatment of craniosynostosis is based on the fundamental work by Tessier. However, developmental aspects suggest modified osteotomy lines like fronto orbito nasal advancement combined with a modified midfacial distraction. This also makes it possible to take assess the different distances of the anterior displacement of the individual parts of the skull. Pioneering in therapy is less the syndrome itself than the accompanying symptoms such as respiration and intracranial pressure. For brain release we recommended (Joos 1998) the osteoclastic procedure according to Powiertowsky (1974) within the first 6 months of life. For further treatment frontoorbito-nasal advancement and modified midface distraction seem to achieve better results in enlarging the inner nose and a more harmonious profile.

Craniofacial Distraction: Orthodontic Considerations.

A combined surgical and orthodontic approach to midface and mandibular distraction optimizes stability and outcomes. Orthodontic considerations include proper planning of the distraction vector, appropriate device use, and thorough follow-up through the consolidation and postoperative period. The dental occlusion must be managed throughout treatment in order to achieve ideal results.

Craniosynostosis: Le Fort III Distraction Osteogenesis.

The Le Fort III advancement was first described in 1950 and has since become a key technique in the armamentarium of craniofacial surgeons. The application of distraction osteogenesis to the craniofacial skeleton has allowed for large movements to be performed safely in young patients. This technique is valuable for correcting exorbitism, airway obstruction owing to midface retrusion, and class III malocclusion. It can be performed with either an external distractor or internal distractors. Although serious complications have been reported, these occur rarely when performed by experienced providers.

Counterclockwise Craniofacial Distraction Osteogenesis.

Anatomic studies have identified that patients with Treacher Collins syndrome and some cases of bilateral craniofacial microsomia are characterized by multilevel airway obstruction as a result of hypoplasia and clockwise rotation of the maxillomandibular complex. Patients often remain tracheostomy-dependent despite multiple airway surgeries. Counterclockwise craniofacial distraction osteogenesis aims to correct the facial skeletal deformity and expand the upper airway volume by rotating the subcranial complex en bloc around the nasofrontal junction. Early results have demonstrated significant increases in the nasopharyngeal and oropharyngeal airway volumes with successful decannulation in a majority of patients who have undergone this operation.

A low-cost method of craniofacial distraction osteogenesis.

AIM: Distraction osteogenesis is an effective treatment modality for the correction of craniofacial deformities. The cost of these devices is significant and may preclude routine use of these distractors in developing countries. Hence, distraction osteogenesis was performed using medical equipment that was readily available in any hospital at minimal cost. PATIENTS AND METHODS: From 2008 to 2013, a retrospective study was performed on infants and neonates who underwent primary distraction for craniofacial abnormalities. Midface or mandibular distraction was performed because of respiratory impairment and/or globe exposure. The apparatus used included Steinmann pins, stainless steel wires, attachment bolts, orthopaedic pulleys, string and intravenous bags for weights. For midface distraction, a transzygomatic pin was inserted, and a transmandibular pin or a cerclage wire was inserted into the mandible through the symphysis or body of the mandible and connected to the pulley system. RESULTS: Distraction osteogenesis was performed on five patients - three mandibular distractions (Pierre Robin sequence) and two transfacial distractions (Apert syndrome/Pfeiffer syndrome type III). The mean age, duration of distraction and duration of consolidation at the time of distraction was 60.5 days, 18.6 days and 16.4 days, respectively. The mean length of distraction achieved was 12 mm. Common complications observed were pin loosening, pressure necrosis of the skin and uneven pull. A major disadvantage was the longer hospital stay required. CONCLUSION: The African method of distraction is effective, easy and cost effective and could be used in third-world hospitals where surgical expertise or expensive distraction sets are not freely available.

Wide alveolar cleft and midface distraction: Report of a case.

BACKGROUND: Cleft lip and palate patients often present wide alveolar cleft and midface hypoplasia. Closure of such wide alveolar clefts may be difficult using bone graft. Traditional orthognathic surgery for midface advancement shows relapse. Distraction osteogenesis (DO) as a modality for midface advancement has shown good results with external distractors. Use of internal distractor (ID) further improves patient compliance, causes minimal discomfort and offers the advantage of limiting relapse. The purpose of this study was to evaluate the versatility of intraoral distracters in midface advancement in cases with alveolar cleft. METHOD: A 16 years old young girl with midface deficiency and alveolar cleft visited our outpatient clinic for aesthetic improvement and midface distraction was planned. After Le Fort I osteotomy, internal distractor was fixed. A latency period of 5 days was allowed and then distraction was started at the rate of 1 mm per day in two installments. Evaluation was done for closure of cleft, ease of the procedure, stability, and complications. Lateral cephalograms were evaluated at three stages: predistraction; post-distraction; and 1 year post-distraction. RESULTS: Complete closure of alveolar cleft was observed with 17 mm midface advancement and bone formation at the pterygomaxillary region. Maxillary position improved in relation to the cranial base. The results were stable even at 1 year follow-up. CONCLUSION: Distraction osteogenesis using intraoral distractors was successful in alveolar cleft closure, as well as midface advancement in terms of stability of results and patient compliance with minimal complications.

Syndromic craniosynostosis.

Although most cases of craniosynostosis are nonsyndromic, craniosynostosis is known to occur in conjunction with other anomalies in well-defined patterns that make up clinically recognized syndromes. Patients with syndromic craniosynostoses are much more complicated to care for, requiring a multidisciplinary approach to address all of their needs effectively. This review describes the most common craniosynostosis syndromes, their characteristic features and syndrome-specific functional issues, and new modalities utilized in their management. General principles including skull development, the risk of developing increased intracranial pressure in craniosynostosis syndromes, and techniques to measure intracranial pressure are discussed. Evolving techniques of the established operative management of craniosynostosis are discussed together with more recent techniques including spring cranioplasty and posterior cranial vault distraction osteogenesis.

Development and evolution of distraction devices: Use of indigenous appliances for Distraction Osteogenesis-An overview.

An attempt has been made to review various devices as well as the outstanding studies done in the past for understanding the methodology of distraction for regeneration of bone. Lengthening of underdeveloped bones inclusive of the maxillofacial complex has been obtained by distraction osteogenesis by many authors. This could be achieved by the use of various extraoral or intraoral devices. Devices used for distraction osteogenesis must have a minimum of 2 important characteristics - they should be able to transfer distraction forces directly to the bone and secondly, should offer adequate rigidity for osseous consolidation to occur. With advanced technology and biomechanical engineering, preformed intraoral distraction devices are now available worldwide. The introduction of these intraoral bone-bourne devices have eliminated the need for bulky, cumbersome extraoral distraction devices which had problems such as external scars, pin tract infections, nerve or tooth bud injuries and poor patient compliance. The design of completely internalized custom made appliance has opened new vistas in the field of Oral and Maxillofacial Surgery. Indigenous internal devices are also economical and locally available.