To the general population, orthognathic surgery (i.e. jaw surgery) can be seen as a cosmetic procedure done to satisfy our vanity. The truth is that the majority of orthognathic patients seek treatment due to an inability to properly chew food, speak or smile. The physical, psychological and physiological turmoil takes a major toll on the patients’ quality of life.
Orthognathic patients must first get braces 6-12 months prior to surgery. The purpose of this is to decompensate the teeth. Over time, our bodies adapt to what we’re given. For example, a Class III patient’s dentition will be compensated by having their upper teeth positioned outwards while their lower teeth are oriented inwards in order to maximize the surface area used in mastication. By decompensating the teeth, the bite will get worse and more pronounced. In addition, the orthodontist will place surgical hooks on the brackets so the jaws may be wired during the operation. Models will be taken and assessed by both the orthodontist and oral surgeon to get the green light for surgery.
Orthognathic surgery is a fine balancing act that takes into account the patient’s maxillofacial anatomy and the surgeon’s expertise. A patient may have just one jaw repositioned to achieve a more optimal bite. However, in complex cases involving asymmetry, it is recommended that both upper and lower jaws be moved.
The most commonly done procedure on the upper jaw is the LeFort I osteotomy. The versatility of this procedure in upper jaw re-positioning make it the primary option. For the lower jaw, there are two main procedures available: the bilateral sagittal split osteotomy (BSSO) and the intraoral vertical ramus osteotomy (IVRO). The differences between these two lower jaw procedures lie in the location of their bone cuts and the cases that they are able to treat. The BSSO encroaches upon the inferior alveolar nerve, which is extremely important for sensory in the lower third of the face. Any trauma to it may result in temporary and permanent parasthesia. On the other hand, the IVRO completely avoids the inferior alveolar nerve as it is made further back on the lower jaw.
The BSSO may be used for both lower jaw advancements and setbacks. It is especially used in U-shaped mandibles as assessed by a cone beam CT scan. For V-shaped lower jaws that require a setback, the IVRO is performed.
Mandibulomaxillary fixation (MMF) uses surgical hooks as an anchor to hold the teeth in its final occlusion. Small titanium screws and plates are used to fixate the jaws in their new position. This rigid fixation provides stability during the healing process. And no, patients will not set off any alarms at the airport nor will they be able to stick refrigerator magnet to their face. However, they will have a fully functional textbook occlusion and join the Class I occlusion club.
Immediately following surgery, patients experience facial swelling and throat discomfort. Depending on the extent of the surgery, the degree of healing will be varied. Most patients begin drinking clear liquids before progressing to soft textured food such as mashed potatoes and ice cream. The IVRO requires patients to be wired shut for 6-8 weeks as they remain on a completely liquid diet.
Many patients lose up to 20lbs following recovery. In addition, their new bite will feel extremely weird as the patient adjusts to a new occlusion. Within six months, braces will be taken off. The orthognathic journey is an arduous undertaking. On average, it takes two years to attain the coveted Class I occlusion. It is important for patients to have a strong support system of family and friends who understand the patient’s desire to have a normal bite.
The majority of orthognathic patients do not regret their decision and rave about its life changing effects. Increases in quality of life due to optimal bite functionality and closer facial symmetry are the two most noted differences. Gone are the days when their skeletal disharmony interfere with their livelihood. Patients find newfound confidence when smiling, chewing and interacting with peers. The profound effects of orthognathic surgery greatly improve all facets of patients’ lives and is an endeavor worth pursuing.
~Will Pang, New York University ’16, predental