Things you should know before the surgery.
Orthognatic surgery is an elective surgery, so a patient has to be absolutely healthy and free of viral infections of the airways 2-3 weeks before surgery. Once the infection of upper respiratory tract develops, surgery must be postponed for at least 2 to 3 weeks.
In addition, stomach has to be empty before surgery. If the surgery is scheduled in the morning, last meals can be taken no later than 8 p.m. and drinks no later than 10 p.m. the evening before. It is strictly forbidden to drink or eat in the morning before the surgery since food aspiration may end up in fatal outcome. Female patients are advised to come without make-up, earrings, or nail lacquer applications on nails.
Things you should bring to the hospital.
- Documents: passport or ID card, social security card, or other documents that may be required in your state hospital. Also you will probably need your orthodontist referral letter and your medical examination results.
- Comfortable clothing: it may by a sports suit or any other light warm clothes. It is better to wear clothes with zippers or buttons to make undressing easier during the period of massive facial swelling after the surgery.
- Foot-wear: slippers or light sport shoes.
- A tooth brush and tooth paste.
- A cup with a spout or a >20cc syringe with attached tube - these are the main tools that facilitate food intake after the surgery. When lips are swollen it is hard to eat with a spoon or even through a straw.
- Food supplements and nutrient supplies may diversify the diet for the first week after the surgery. They may be country-specific, so ask your oral and maxillofacial surgeon for more details.
Duration of surgery. Operation is performed under general anaesthesia and it may take from 1.5 hours for one jaw and up to 6 hours for segmental double jaw surgery and bone grafting to complete. It may take up to 6.5 hours if the surgery is performed on both jaws and a chin.
Scars. Cuts are performed inside the mouth in oral mucous membrane, therefore the face is not disfigured by scars.
The course of surgery. The lower jaw is split along into three parts: two joint bearing side parts and a central part which contains teeth. Then the central part is moved to the needed position: advanced or set back, rotated if needed and fixed to the side parts with titanium plates and screws. Having done this, the upper jaw is accessed, split and separated from the skull base. If needed it is cut into 3 to 4 parts and fixed in the new correct position with titanium plates and screws. Additional amount of bone is harvested from the chin area, cheek bones or even iliac crest if the amount of bone particles collected during surgery is not sufficient to pack in the packs between the bone segments or jaw cut locations. Chin advancement or reduction surgery may be performed additionally where chin is cut, moved to the desired location and fixed with plates and screws. Surgery ends when all wounds are closed.
Discharge from the hospital. Usually patients spend 1-2 days in a hospital after one jaw surgery and 2-3 days after double jaw surgery, although it may depend on the operating surgeon and regional regulations.
Recovery. Soft tissue wounds heal in 10 days on average. Lower jaw consolidates in two months while it takes about 4 months for the bone union to form in the upper jaw.
- Infection and suppuration – a rare complication since blood circulation in facial region is rich. Antibiotic regimen after the surgery helps to avoid this problem.
- Bad split – may happen on a rare occasion in a case of atypical anatomy or an undiagnosed jaw defect, like cyst. This may be avoided by doing cone-beam CT scanning before surgery and performing a thorough investigation of both jaws. This complication is hardly possible for a healthy patient since the surgical technique is very well established.
- Jaw joint resorption and the relapse of the malocclusion relapse. A rare complication that may be connected with systematic diseases (e.g. rheumatoid arthritis), parafunctions (bruxism, clenching) and poor surgical technique.
- Non-union of jaw fragments or fracture of titanium plates. This may be possible if a patient begins chewing food earlier than is allowed to or if he/she bruxes at night. Prescribed medications may reduce bruxism, whereas extensive bone grafting during surgery and patient compliance after surgery may help avoid non-union and plate fracture.
- Long-lasting facial swelling – possible for people who have a turn for swelling.
Facial sensation disorders. After a lower jaw surgery patients experience reduced sensation in the lower lip and chin but motion and mimic of the lips remains unaltered. Absolute numbness in the lower lip and chin may be felt for about 2 months. Usually sensation returns in 2-18 months. During this period uncommon feelings like itching or tingling may be felt. For more than 95% of patients sensation recovers completely