Orthognathic surgery, commonly known as jaw surgery, is a sophisticated procedure designed to correct severe misalignments of the jaw structure. When the upper and lower jaws do not fit together correctly, it can affect not only the appearance of the face but also the ability to chew, speak, and even breathe effectively. This surgical intervention carefully repositions the facial bones to establish a balanced profile and a proper bite relationship.
How Surgeons Plan the New Profile
The final appearance of the jaw is precisely determined long before a patient enters the operating room through Virtual Surgical Planning (VSP). This modern approach begins with comprehensive diagnostic records, including Cone-Beam Computed Tomography (CBCT) scans and high-definition scans of the dental arches. The CBCT provides a three-dimensional map of the craniofacial anatomy, which is then integrated with the digital dental models. The surgeon utilizes specialized software to perform the entire operation virtually, simulating the precise movements of the maxilla (upper jaw) and mandible (lower jaw) in all three dimensions. This planning allows for the exact visualization of the bone cuts and the resulting changes to the facial soft tissues. Based on this digital blueprint, custom surgical splints or guides are fabricated using 3D printing technology. These physical guides translate the virtual plan directly to the operating room, ensuring the new jaw position is reproduced with high accuracy.
What Happens During the Operation
The procedure is performed under general anesthesia and typically requires a one- to two-night stay in the hospital. Surgeons access the jawbones almost entirely through incisions made inside the mouth, using an intraoral approach that leaves no visible scars.
The core of the surgery involves a technique called osteotomy, which is the controlled surgical cutting of the bone. For the upper jaw, a Le Fort I osteotomy is commonly performed to separate the maxilla from the rest of the face. The lower jaw often involves a Bilateral Sagittal Split Osteotomy (BSSO), which splits the mandible on both sides to allow the jaw to be moved forward or backward.
Once the jaw segments are moved into the pre-planned position, they are secured using small titanium plates and screws. These devices provide rigid fixation, which stabilizes the bones and promotes optimal healing. The use of these plates and screws has largely eliminated the need to wire the jaws completely shut, a practice common in older surgical techniques.
Immediate Appearance and Recovery
In the immediate aftermath, the patient’s appearance is dominated by swelling, which is an expected and dramatic part of the healing process. This facial swelling concentrates around the cheeks, lips, and neck, and it typically peaks around the third or fourth day post-surgery. To manage this, patients often have a cooling head wrap applied, and they are instructed to keep their head elevated constantly.
Bruising is also common, especially after lower jaw procedures, and can be visually striking, sometimes extending down to the upper chest area. The teeth are often held together with tight orthodontic elastics attached to the braces, which helps maintain the new bite alignment and limits jaw function during the initial healing period. This restriction necessitates a full liquid diet for the first several weeks, as the jaw cannot be used for chewing.
Numbness in the lips, chin, and cheeks is temporary but common due to the manipulation of the jawbones near the nerves. While most swelling subsides significantly within the first few weeks, a subtle, residual puffiness may linger for several months. The initial look is visually dramatic due to the fluid retention and limited mobility, but this is a temporary stage of healing.
Long-Term Results and Functional Changes
The long-term outcome of orthognathic surgery is a significantly improved facial profile and enhanced functional capacity. Once the swelling fully resolves over several months, the aesthetic results become apparent, including greater facial symmetry and a more defined jawline or chin projection. The procedure corrects skeletal discrepancies like severe overbites or underbites, which profoundly affect the balance of the lower face.
Beyond the aesthetic improvements, the functional changes are a primary goal of the surgery. The repositioned jaws create a stable and proper occlusion, or bite, which improves the ability to chew food efficiently. The surgery can also resolve issues with speech and significantly improve airway dynamics. For patients with obstructive sleep apnea, procedures like maxillomandibular advancement can increase the volume of the airway, leading to better breathing and sleep quality.