maxillary distraction osteogenesis

Maxillary distraction osteogenesis is used for prolongation of craniofacial bone traction. Treating diseases: maxillary retraction Indication The general condition is the same as that of orthognathic surgery and implant surgery. The main diseases currently available for treatment with DO are: 1. (Upper, lower) stenosis of the dental arch - crowded dentition (pre-orthodontic treatment without extraction). 2. Small jaw deformity (with sleep apnea syndrome). 3. The second sacral arch syndrome, hemifacial hypoplasia or hemifacial atrophy. 4. Partial malformation. 5. Inferior facial development caused by maxillary retraction deformity and cleft palate. 6. The distance between the jaws is too low. 7. The alveolar ridge is too low or defective. 8. Old fractures are 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 defects. The age of the patient's surgery is generally considered to begin DO surgery after 4 years of age. In addition to considering the regenerative capacity of the patient's bone and soft tissue, they also need to take into account their ability to cooperate. Contraindications Basically the contraindications for surgery in orthognathic surgery, as well as: 1. Jaw osteomyelitis. 2. Severe jaw osteoporosis. 3. Blood system diseases. Preoperative preparation The surgeon must have basic knowledge and skills in orthognathic surgery, orthopedics, strong internal fixation of the jaw, and orthodontics. 1. Photographic standard positive lateral position, 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 tomogram, dome film, and if necessary, design the teeth in the osteotomy area to Get accurate tractor placement. 3. Head shadow measurement analysis and model analysis. 4. According to the paper cutting surgery and model surgery design osteotomy line, traction direction, simulate the tractor placement surgery. 5. Teeth cleaning. 6. Appropriate preoperative compensation for orthodontic treatment. 7. The assisted orthodontic treatment plan in traction, and proposes a solution to open and adjust the bite. 8. Evaluation of temporomandibular joint. 9. Oral cleansing, preparation of skin around the mouth. Craniotomy requires scalp preparation. Surgical procedure Incision The bilateral canine to the anterior sulcus at the bottom of the first molar was incision, and the midline vertical incision was used to cut the nasal septum. 2. Osteotomy According to the design, the high-grade LeFortI or type II osteotomy should be included. The posterior superior incision should include partial humerus. The anterior maxillary sinus should avoid the infraorbital nerve vascular bundle, pay attention to protect the lacrimal sac, and cut the maxillary nodules and nasal septum. . Use the osteotome to move forward in the maxillary nodule area, confirming that the maxillary mass has been loosened, but not to fracture the upper jaw. 3. Placement of the tractor According to the model surgical prefabricated tractor, the internal fixation can be performed with a slight internal fixation (Fig. 10.3.8.3-6). Since the outer (post) side wall of the maxillary sinus is thin, the rear fixed wing of the tractor is placed on the humerus, and the front fixed wing of the tractor is placed as close as possible to the position of the alveolar ridge to obtain a strong anchorage. The tractor vector thus placed may be facing forward and downward, and is more suitable for patients who are too short in 1/3 of the face. 4. Suture incision The wound is sutured intermittently and the forcing end of the retractor is exposed to the oral cavity. 5. Afterburner Due to the rich blood supply of the maxilla, it has recently been advocated to apply the force immediately after the placement of the tractor. The speed of the afterburning and the rhythm are the same until the designed migration. 6. Maintain a gap that can be maintained with a tractor, arch cleat, bracket archwire or temporary denture. The duration of the maintenance period is generally shorter than that of the mandible. 7. After the tractor is removed, the X-ray must be bitten to determine the density of the bone density in the traction gap close to the surrounding bone to remove the tractor. 8. Continue orthodontic treatment to align the upper jaw dentition and adjust the bite relationship. An external headstock type tractor is also used in the middle of the front face.