temporomandibular joint hypoplasty

The temporomandibular joint ankylosis is difficult to open or open at all because of unilateral or bilateral joints or fibrous or bony adhesions within the joint. It can be divided into: Intra-articular rigidity: Most children who occur before the age of 15 are commonly caused by inflammation, which is caused by the spread of suppurative inflammation of adjacent organs. Among them, suppurative otitis media is the most common. Extra-articular rigidity: The common cause is damage, such as the open jaw fracture of the jaw nodule, the mandibular ascending branch or the firearm injury, which forms a scar of contracture between the upper jaw and the lower jaw. One of the common causes of extensive scarring of the cheek tissue after various physical and chemical third-degree burns on the face. Surgery for intra-articular ankylosis includes condylar resection and temporomandibular joint surgery. Treatment of diseases: temporomandibular joint rigidity Indication 1. The extent of joint ankylosing bone adhesion has affected the sigmoid notch. 2. Postoperative recurrent joint rigidity. 3. Mixed joint rigidity. Contraindications The general condition cannot tolerate anesthesia and surgery. Preoperative preparation 1. Routine bilateral X-ray examination to determine the location, nature and extent of the lesion, and to identify no external joint adhesion lesions, in order to make a preoperative design. 2. Pay attention to check the presence or absence of secretions in the external auditory canal. Patients with otitis media should be treated first. 3. Plan to put the inserts in the operation, prepare the insert materials in advance, and disinfect them for use. Regular blood matching. Surgical procedure Incision Take the modified submandibular incision, starting from 1cm below the earlobe, down the mandibular angle, parallel to the lower jaw of the lower jaw 1.5cm, and stop at 2cm before the chewing muscle. 2. Reveal the outer side of the mandibular ascending branch The skin, subcutaneous tissue and platysma are cut along the incision line. The mandibular branch of the facial nerve can be dissected at the anterior incision of the mandibular angle, and then the external and external veins of the maxilla are separated and ligated. The periosteum and the chewing muscles are then cut along the lower edge of the mandible and the mandibular angle, and separated from the bone surface by the periosteal stripper to reveal the lateral side of the mandibular ascending branch. Continue to separate upwards, explore the sigmoid incision and the condylar neck, understand the extent of osteophyte hyperplasia, and separate the posterior margin of the ascending branch and the medial periosteum at the osteotomy. In addition, when the submandibular incision is exposed, and the lower pole of the parotid gland is separated from the sternocleidomastoid muscle along the parotid fascia, the parotid gland can be turned up together with the chewing muscle, so that the ascending branch and the sacral neck are better exposed. 3. Osteotomy The osteotomy line is generally selected between the sigmoid incision and the mandibular hole, and osteotomy can be performed by osteotome or wire saw. Deboning with osteotome, methods and precautions are the same as high osteotomy. Because of the exposure, it is not easy to make the instrument reach vertical osteotomy. Therefore, it is especially necessary to avoid the formation of a wide-width, deep-faced osteotomy gap. Using a wire saw to cut the bone, first take the two wire saws from the large curved vascular clamp or the aneurysm needle to the inner side of the lower jaw ascending branch, saw the lower cut bone line, and then pull the upper wire saw to remove the A section of bone, forming a 1 cm wide osteotomy gap. When cutting the bone, care should be taken to protect the soft tissue inside and the leading edge of the ascending branch to prevent damage to the inferior alveolar nerve and blood vessels. 4. Trimming the osteotomy gap Use the rongeur to repair the broken end of the bone, make the width of the deep and shallow section of the osteotomy gap uniform, and narrow the width of the wide branch to form a rounded shape to facilitate the joint movement. 5. Place the insert Regarding the placement of the insert, in addition to the high-level osteotomy, it can be used: 1 chewing muscle flap transfer: When the osteotomy gap is formed, a pedicled muscle flap is formed in the deep layer of the raised chewing muscle. Large, small, long, and wide to cover the osteotomy section. The muscle flap is then transferred into the osteotomy space and sutured to the surrounding tissue and the pterygoid muscle without tension. 2 skin intercalation method: take the fault layer or full thickness skin 6cm × 4cm, use the gut to sew into a small bag, then flip the small bag, make the leather surface turn inside, create a face-to-face, fill the bag with iodoform yarn, osteotomy After the gap is formed, the bag-shaped skin piece filled with the iodoform gauze is placed in the gap, and one end of the iodoform gauze in the bag is taken out through the incision, and the iodoform yarn strip is completely withdrawn 10 to 12 days after the operation. 3 fascia: Take the left leg fascia 6cm × 4cm, so that the fascia faces the fascia. Sewn into a cap, placed at the end of the osteotomy, and drilled at the broken end of the bone, wearing a thin wire to fix the fascia cap. 6. Close the wound Rinse thoroughly, stop bleeding, suture the wound in layers, and place half of the rubber tube for drainage. When suturing the muscular layer, be careful to pull the end of the chewing muscle that is retracted upward to suture the stump of the chewing muscle. complication 1. Respiratory obstruction The rigidity of the pharyngeal cavity is narrow. After the osteotomy, especially in patients with bilateral joint stiffness, the pharyngeal cavity is further reduced due to the mandibular retreat. If the anesthesia cannula is removed after the operation, it is easy to remove the anesthesia. Suffocation occurs after falling. In addition, pediatric patients, due to blind intubation injury or long operation time, are also prone to laryngeal edema and cause airway obstruction. Therefore, it must be completely awake before extubation, at the same time prepare for tracheostomy, and actively prevent laryngeal edema, to avoid airway obstruction. 2. After the operation of the open jaw and mandibular oblique joint, the fulcrum is shortened, the fulcrum is moved forward, and the mandible is rotated backward. The bilateral patients develop open jaw, and the unilateral side mainly shows the mandibular to the affected side. Skewed. The open jaw can be improved by intermaxillary traction, and the mandibular deviation can be corrected with a beveled guide. 3. Postoperative wound infection Joint stiffness surgery If infection occurs, it may lead to postoperative recurrence. Therefore, skin preparation must be done before surgery, and strict aseptic operation should be performed during operation to actively prevent wound infection. After the operation, the wound should be closely observed, and the local swelling should be noticed. The signs of infection should be treated in time. For example, the whole body should be switched to broad-spectrum antibiotics, local drainage, blood accumulation, and effusion. If the wound has been purulent, it should be drained in time. If the foreign material is inserted, it should be taken out. 4. Recurrence of joint rigidity According to reports in the literature, the recurrence rate is between 10% and 25%. The recurrence is the most in 1 to 2 years after surgery, and the chance of recurrence tends to decrease with the prolongation of time. The cause of recurrence is not fully understood, but it is closely related to the patient's age, surgical methods, and techniques.