疾病动物模型,双侧下颌升支垂直截骨术 z-bio 2021-03-16 675

　　Orthognathic surgery and experimental animal research of the temporomandibular joint is an animal model that simulates various orthognathic surgery operations of the human body and observes the postoperative morphological and functional changes of the temporomandibular joint. To study the impact of orthognathic surgery on the temporomandibular joint. United. Important means. Wang Hao et al. established a bilateral vertical osteotomy of the maxillary ramus with mini-pigs.

　　1. Experimental method Four 12-month-old Chinese experimental miniature pigs weighing 35-40 kg were selected for the experiment. They were randomly divided into 4 groups. The first group moved the forward 6 mm, the second group moved the forward 3 mm, the third group moved the back 3 mm, and the fourth group was the blank control group. After routine anesthesia for the piglets, lie down, shave, disinfect, and drape, first make an incision on the left submandibular gland, directly into the bone surface, and then use a periosteal separator to perform subperiosteal separation along the periosteum. The notch surface of the submandibular gland below the arch. The advance group uses a split drill to create two vertical osteotomy marking lines on the outside of the upper jaw branch, where the distance from the S-shaped notch to the lower end of the mandible is equal to the amount of travel. Completely polish the split drill along the two vertical osteotomy lines. Maxillary branch. The proximal and distal bone segments were ligated and fixed with a double-stranded stainless steel wire<0.3mm. If you need to replace the, draw a vertical osteotomy line from the S-shaped notch to the central part of the ascending branch, and then perform a horizontal osteotomy on the posterior edge of the mandible, mesial bone and distal end. . Cut a 3 mm wide full-thickness bone fragment from the lower half of the posterior edge of the mandible, and transplant it into the vertical incision of the mesial bone segment, and then retract the con-bone segment by 3 mm. After the osteotomy and wire ligation are completed, the surgical site is washed with saline, and the periosteum, muscle layer, subcutaneous and skin layers are sutured in layers. Use the same surgical procedure to complete the contralateral vertical osteotomy. use

　　GE's Prospeed II full-body scanner, the miniature pig will be in a supine position during the scan. The pig’s head and spine form a 900-degree angle with the temporomandibular joint. The layer thickness is 1 mm. There is no middle layer in the spiral scan. Start from the 1-2 cervical vertebrae interval and go to the front third joint of the mandible. After the scan is completed, a 2D tomographic reconstruction will be performed and a curved sagittal reconstruction will be used to better show the condition of the joints. First, choose a well-displayed joint level as the tomography standard. Then draw the tomography curve and pass through the center of the joint and the ascending branch bones to ensure the best sagittal tomography. Finally, save the best image and take a laser photo. camera. The preparations were compared before operation, after operation, 1 week after operation, 4 weeks after operation and 16 weeks after operation, and the changes of the bilateral temporomandibular joint space were observed.

　　2. Experimental results The three pigs grew well after the operation, and the wounds healed according to the original intention. Compared with the control group, when the three pigs were fed with the same diet, no abnormal chewing movement was found during the postoperative feeding process. One week after the operation, the specimen was removed and the two mandibular branches of the mandible were subjected to vertical osteotomy, but the osteotomy did not heal. Fibrous connective tissue was found at the bone stump, and the steel wires ligated to the maxillary branches on both sides were strong and not loose. The surface of the temporomandibular, depression process and left and right temporomandibular joint discs is smooth. No defects or deformation.

　　Collected 4 weeks after the operation, after bilateral mandibular vertical osteotomy, the gastric stump healed in the first stage. The wires tied to the upper and lower jaws are strong and not loose. The surface of the infratemporal fossa, con and intervertebral disc of the temporomandibular joint is smooth, without defects or deformation. The specimen was performed 16 weeks after the operation, and the fracture healed in the first stage after bilateral vertical mandibular osteotomy. The steel wires ligated with the maxillary branches on both sides are covered by the healed cortex, the lateral bone surface of the ascending branch is smooth; the surface of the articular discs of the temporomandibular fossa, con, and left and right jaw joints is smooth. There are no defects or deformations. when

　　When moves forward 6 mm, the space between the front and back of the temporomandibular joints on both sides expands, and the both sides move downward and forward. Moving the forward 3 mm can reduce the anterior space of the bilateral temporomandibular joints, expand the posterior space, and move the bilateral temporomandibular joints forward. When the process returns to 3 mm, the anterior gap of the temporomandibular joint increases, the posterior gap decreases, and the bilateral con processes move back. Comparing the blank control group with the first, second, and third groups before operation, 1 week after operation, 4 weeks after operation, and 16 weeks after operation, there was no significant change in the temporomandibular joint. Joint space on both sides.