Bilateral distraction osteogenesis for mandibular advancement

Bilateral traction osteogenesis mandible advancement for the extension of craniofacial bone traction. Curing disease: Indication 1, (upper, lower) dental arch stenosis - crowded dentition (pre-orthodontic treatment without extraction). 2, small jaw deformity (with sleep apnea syndrome). 3, the second arch syndrome, half of the facial hypoplasia or half of the face atrophy. 4, partial deformity of the jaw. 5, maxillary retraction deformity, cleft palate caused by lack of central development. 6, the distance between the jaws is too low. 7. The alveolar ridge is too low or defective. 8, old fractures healed. 9, the bones are not connected. 10. Jaw defects. 11, congenital craniofacial deformities, such as Crouzen, Robin, Treacher-Collins and other syndromes. 12. Skull defect. Contraindications 1, jaw osteomyelitis. 2, severe jaw osteoporosis. 3. Blood system diseases. Preoperative preparation 1, the camera standard positive side, dentition and bite relationship. 2, X-ray film treatment plan must use complete imaging data, such as standard positive lateral cephalometric film, full-mouth curved tomography, dome film, if necessary, design the teeth in the osteotomy area, Get accurate tractor placement. 3. Head shadow measurement analysis and model analysis. 4. Design the osteotomy line and traction direction according to paper-cut surgery and model surgery to simulate the placement of the tractor. 5, the teeth are cured. 6, appropriate preoperative compensation to orthodontic treatment. 7, assisted orthodontic treatment plan in traction, proposed to solve the problem of opening and adjusting bite. 8, temporomandibular joint evaluation. 9, oral cleaning, oral preparation of skin. Craniotomy requires scalp preparation. Surgical procedure 1. Incision The mucosa and submucosal tissue were incised along the leading edge of the oral mandibular ascending branch or the external oblique iliac crest. The lower end of the incision was slanted outward and downward to reach the distal surface of the distal vestibular sulcus of the first molar. The periosteal is used to expose the lower jaw. Lateral bone plates and alveolar ridges, but minimally remove the periosteum, muscles and soft tissue to protect the blood supply. 2. Osteotomy of the inferior alveolar neurovascular bundle The lower edge of the mandible corresponding to the second and third molars is exposed by a lower jaw of the mandible, and the third molar region is used to cut the lower edge of the mandible from the lower to the lower 3600 of the inferior alveolar nerve tube; The buccal cortical bone plate was cut from the outside to the inside; finally, the alveolar ridge was cut from top to bottom to 3 mm from the inferior alveolar nerve canal. When the lingual cortical bone is incision, a periosteal stripper should be placed under the lingual mucosa to protect the lingual nerve. 3. Placement tractor According to the preoperative design, the tractor must be parallel to the bite plane to prevent the anterior teeth from opening; it is recommended to use a double cortical screw to fix the tractor. The position of the screw should be at least 5 mm from the osteotomy line and avoid the inferior alveolar nerve vascular bundle; Because the transverse diameter between the two mandibular angles is wider than the transverse diameter between the canines, the front wing of the tractor should be bent into a step to compensate for the difference in the front-rear direction; according to the Newton force and reaction force law, to prevent any bad load on the TMJ During traction, Class II elastic traction should be applied on both sides to antagonize adverse forces. 4, complete the bone incision The tractor can be unscrewed by 1 to 2 mm, and then a thin bone knife is used to shake the bone around the alveolar nerve canal from the alveolar ridge. After the bone is cut, tighten the tractor. Since the tensile stress is preloaded on the osteotomy line, the cleft palate line can easily reach the alveolar crest without breaking through the gingival tissue. At this time, the retractor is reversely screwed into the 2 mm to make the osteotomy line close. Will be beneficial to the formation of callus. 5, suture wound The connector and the forcing end of the tractor should be exposed to the oral cavity as much as possible, and the wound should be sutured intermittently to tightly wrap around the fixed wings of the tractor. When using a tractor with a dentition-bone joint anchor, the ligation wire of the dental end can be fixed with the teeth by self-setting plastic to prevent the steel wire from loosening. 6, afterburner Generally, the force is started after 7 days of intermittent operation, and after reaching the designed extension distance, the bone healing is maintained until the traction gap. Orthodontic doctors are required to monitor and adjust the bite relationship during the maintenance period to improve orthodontic treatment. When performing DO in the mandibular body, it is also necessary to protect the inferior alveolar nerve vascular bundle, and try to avoid root exposure on the osteotomy line.