Dental and maxillofacial malformations are mainly due to abnormal development of teeth and jaws, abnormal function of the oral and jaw systems and abnormal facial morphology. There are two types of malocclusion, one is caused by the misalignment of teeth, and the development and position of upper and lower jaws are normal, which is called “dental malocclusion”, and this type of malocclusion does not require surgery, but only requires a dentist to rearrange the teeth. On the contrary, if the malocclusion is caused by the abnormal development of the upper and lower jaws, which is called “bony malocclusion”, it needs to be treated surgically. In most cases, osseous malformations are accompanied by varying degrees of dental malformations, and it is difficult to achieve the desired result by simply aligning the teeth without surgically correcting the abnormal jawbone. The types of osseous malformations are very complex, with maxillary protrusion malformation and antimandibular malformation being the most common in clinical work. These two types of deformities are highlighted as examples. Maxillary protrusion deformity: commonly known as “open lips and teeth”, “blunt teeth”. Antimandibular deformity: commonly known as “envelope”, “pocket tooth”. There are three causes: (1) maxillary retrusion; (2) mandibular protrusion; (3) maxillary retrusion and mandibular protrusion. Your doctor will examine your mouth in detail, make a plaster cast of your teeth, take a whole jaw surface tomogram, cranial orthopantomogram, cranial lateral radiographs, and if possible, a cephalometric radiograph. 4. Your doctor will take a crown-free ortho-lateral image and an ortho-lateral image of the relationship between the teeth and the jaw; 5. 2. Pre-operative orthodontic treatment: After determining the surgical plan, orthodontic treatment will be carried out first according to the planned orthodontic position so that the incised bone segment can be moved smoothly to the designed orthodontic position during surgery; 3. Confirmation of surgical plan: After orthodontic treatment, it is best to carry out an evaluation and forecast of the original surgical plan and make adjustments if necessary to obtain the best Treatment results. Surgical procedure: 1. The surgery is performed under general anesthesia through intraoral incision of the oral mucosa and subperiosteal separation to expose the site of osteotomy; 2. The maxilla or mandible is cut open according to the preoperative design, the bone block is adjusted to the ideal position and a good occlusal relationship is obtained, and finally the bone block is fixed with titanium plates and nails, and the intraoral incision is sutured. (1) For maxillary protrusion deformity, the surgery is mainly performed by osteotomy with special osteotomy and then receding the maxilla to correct the maxillary protrusion; (2) For antimandibular deformity caused by mandibular protrusion, the surgery is mainly performed by osteotomy with special osteotomy and then receding the mandible as a whole to correct the mandibular protrusion; (3) For antimandibular deformity caused by maxillary recession, it is necessary to move the maxilla as a whole forward so as to correct the antimandibular deformity. At the same time, the anterior displacement of the maxilla also significantly improves the mid-facial depression. Individual patients with a low nose after correction of the antimandibular deformity can further increase the three-dimensionality of the midface through rhinoplasty. (4) Patients with antimandibular deformity who have both maxillary recession and mandibular protrusion will need to undergo both maxillary osteotomy advancement and mandibular osteotomy recession. The length of surgery is related to the number of osteotomy sites, generally speaking, the maxillary osteotomy surgery time is relatively long, 2-3 hours, and the mandibular surgery time is generally 2 hours. Post-operative precautions: 1.After waking up from general anesthesia, you can drink a small amount of water and eat liquid food; 2.Routine antibiotics, hemostasis and nebulized inhalation treatment after surgery; 3.Bed rest for 3 days after surgery, and later you can move on the ground; 4.Removal of intra-oral drainage for 3 days after surgery, and removal of intra-oral sutures for 7-10 days; 5.Lips will have edema and pain after surgery, but it will disappear soon; 6.Elastic traction with rubber band between upper and lower jaw after surgery 8-12 weeks to maintain the position of the upper and lower jaws; then remove the traction and further adjust the occlusal relationship in the dentistry department. 7. Regular return visits. Post-operative results: After surgery, the facial contour can be significantly improved from both front and side, and the facial shape has a coordinated upper, middle and lower proportion, and the bite relationship is significantly improved. Your facial shape will greatly enhance your self-confidence. The key to the success of the surgery: The key is the correct diagnosis of the dental and maxillofacial deformities, the design of a reasonable treatment plan, and the ability to actively cooperate with the treatment according to the doctor’s requirements after the surgery.