The procedure commonly described as having the jaw “wired shut” is medically known as Maxillomandibular Fixation (MMF). This technique involves securing the upper jaw (maxilla) and the lower jaw (mandible) together to prevent movement. Fixation is achieved using various methods, most traditionally with thin stainless steel wires wrapped around the teeth and anchored to metal arch bars, or more recently with specialized bone-supported screws. The goal of MMF is to establish and maintain a specific bite relationship, known as occlusion, which is the way the upper and lower teeth align when the jaw is closed. The reasons a person undergoes this restrictive procedure fall into distinct medical categories, ranging from acute trauma repair to planned surgical recovery, and even, historically, as a method of weight control.
Stabilization After Accidental Injury
The most immediate and common reason for MMF is the treatment of severe facial trauma, such as a fractured mandible or maxilla. When the jawbone breaks, the fragments often shift out of alignment, which can compromise the ability to speak, chew, and properly align the teeth. Immobilization is biologically necessary because bone tissue requires a stable environment to heal correctly, similar to placing a broken limb in a cast.
The jaw must be held precisely in its pre-injury position to ensure the fractured bone ends can mend without causing a lasting misalignment of the bite. MMF serves this function by ensuring the teeth act as a guide, locking the jaw into its correct anatomical position. This technique can be used as the definitive treatment for simple, non-displaced fractures, or as a temporary measure to stabilize the bone fragments.
In more complex injuries, MMF is often used right before or during an open reduction and internal fixation (ORIF) surgery, where plates and screws are surgically placed on the bone to provide permanent stability. Even with internal fixation, MMF may be maintained for a period, typically between two to four weeks, to protect the surgical repair during the initial, fragile healing phase.
Post-Surgical Healing and Alignment
MMF is also a standard part of recovery following planned, non-emergency procedures, most notably orthognathic surgery, which is corrective jaw surgery. This type of surgery is performed to correct skeletal problems like severe malocclusion, facial asymmetry, or functional issues that cannot be fully corrected with orthodontics alone. During orthognathic surgery, the surgeon deliberately cuts and repositions sections of the jawbones, such as moving the mandible forward or backward.
Following the repositioning of the bone segments, MMF is used to hold the jaw in its new, surgically corrected position while the bone begins to consolidate. This temporary stabilization is crucial for the long-term success of the surgery, as any movement during the initial healing period could compromise the new dental alignment.
After a period of rigid fixation, wires may be replaced with training elastics, which allow for a gradual increase in jaw movement while still guiding the bite. This controlled mobilization helps the muscles and joints adapt to the new jaw position.
Clarifying the Role in Weight Management
The historical use of MMF for weight loss addresses a different purpose entirely, focusing on calorie restriction rather than structural healing. This method was first documented in the 1970s as a non-surgical alternative to achieve rapid weight reduction in patients with severe or morbid obesity. The procedure works by physically preventing the patient from consuming solid food, thereby enforcing a strict liquid diet.
While patients can achieve significant weight loss, the practice is now considered highly controversial and is rarely used. Modern medicine generally favors safer and more sustainable interventions, such as bariatric surgery or comprehensive lifestyle modification programs. The controversy stems from the severe ethical and psychological implications of physically restricting a patient’s ability to open their mouth.
The main risks associated with MMF for weight loss are severe lifestyle restrictions, poor oral hygiene, and the danger of aspiration. If a patient vomits while their jaw is wired shut, they cannot clear their mouth, creating a significant risk of inhaling the vomit into their lungs, which can be life-threatening. Furthermore, the weight loss achieved through MMF is often temporary; once the fixation is removed, many patients regain the weight because the underlying dietary and behavioral issues were not addressed.