Mandibulectomy

If your cancer is located near or within the jawbone, a surgeon may remove a portion of your mandible (lower jaw) in a procedure known as a mandibulectomy. Additionally, if you suffer from osteoradionecrosis (bone destruction) following radiation therapy, you may need a mandibulectomy.

Of note, a mandibulectomy is different from a mandibulotomy. A mandibulotomy is a cut through the jawbone to gain exposure to the mouth/throat. After the tumor inside the mouth/throat is removed, the mandible is put back together with a plate and screws. No mandibular bone is removed in a mandibulotomy.

How to Prepare

Doctors will give their patients specific instructions regarding what to do before surgery. In general, patients should not eat or drink anything (except essential medications) any time after midnight the night before surgery. Patients should tell their doctor if they begin to feel sick before surgery.

What to Expect

On the day of surgery, the patient will likely be asked to arrive at the hospital a few hours before the scheduled operation. During this time, nurses will check the patient in and anesthesiologists will ensure that everything is safe for general anesthesia. The surgeon will also come see the patient to review the plan and answer any last minute questions.

For all of these cases, the patient will be put completely to sleep with general anesthesia. Patients may or may not require a tracheotomy and/or feeding tube to aid breathing and eating, depending on whether a marginal or segmental mandibulectomy is performed.

Reconstruction

Once a piece of the mandible has been removed, the remainder of the jaw will need to be reconstructed, so that patients can eat, and so their jaws will appear normal. The specific type of reconstruction will depend on how much of the mandible was removed and whether any other types of tissue had to be removed, along with the overall health of the patient. Patients who do not undergo any form of reconstruction will invariably experience a shift in the mandible with jaw displacement resulting from the unopposed pull of the muscles that insert into the jaw to aid in the chewing process. 

For some patients who are not deemed to be good candidates for jaw reconstruction, their mandibular shape and continuity can be restored with a 3 dimensional plate and screws. This technique uses a titanium plate to bridge the gap in their mandible and can restore the occlusal relationships between the upper and lower teeth. Unfortunately, these plates are usually destined to fail due to fracture or extrusion of the plate through the skin of the face or the lining of the mouth. The risk of these complications happening varies with the location of the defect in the jaw and whether the patient has dentition and is able to resume chewing. Defects of the mandible that involve the symphysis (the front portion of the jaw) are most likely to fail due to plate extrusion.  

In most cases, patients who are deemed to be suitable candidates for a longer surgical procedure should be offered a jaw reconstruction with the transfer of a bone from another part of the body (such as the leg, back, forearm or hip). This form of surgery is referred to as a free flap. The purpose of this procedure is to reconstruct the jaw and provide structural support to allow the patient to eat. Patient comorbid conditions and lack of motivation, as well as the lack of existing expertise to perform this elaborate surgery may eliminate this form of restorative surgery from consideration.

Recovery & Aftercare

When the patient first wakes up after surgery, they might have a tracheotomy tube and/or a feeding tube, and will likely have some drains in their neck to help remove any accumulated fluid and prevent infection. In some cases, their jaw may be wired closed to help keep the upper and lower teeth aligned. The patient will be given pain medications to alleviate any pain.

The recovery course will depend on the extent of the surgery and reconstruction. A patient could go home after one or two days in the hospital (marginal mandibulectomy) or could remain in the hospital for one to two weeks (segmental mandibulectomy). The recovery process may also involve physical therapy or speech and swallowing therapy after surgery.

Risks

As with any procedure, there are certain risks associated with undergoing a mandibulectomy. These include:

• Bleeding (including Hematoma)
  If there is severe bleeding after the procedure, the surgeon might need to quickly take the patient back to the operating room to stop the bleeding.  However, some mild bleeding or small blood collections under the skin (hematomas) can be observed without the need to return to the operating room. 
• Seroma
  This is a collection of normal body fluid in the neck that occurs after a surgical drain is removed. This can be treated with observation, as the body will usually resorb it. Alternatively, another approach is to perform repeated needle aspiration to drain the fluid. 
• Infection
  With any surgical procedure, especially those that involve the mouth where there are innumerable bacteria, there is a risk of an infection. This might require antibiotics and/or drainage of the infection.
• Salivary Fistula
  This occurs when there is a small channel (or fistula) that allows saliva to leak from the mouth into the neck. The chances of this increase if a patient has previously been treated with radiation and/or chemotherapy, which impede wound healing. Typically, the treatment of fistulas involves inserting a drain to divert the saliva away from critical structures in the neck, placing packing into the diverted tract, and allowing the body to heal on its own. In some cases, an additional surgical procedure might be required to close the leak.
• Blood Clots
  Patients who undergo major surgeries, especially patients who have cancer, are at an increased risk of developing blood clots in their legs (deep venous thrombosis or DVT). Sometimes these blood clots can travel through the veins and into the lungs, causing a pulmonary embolism (PE). If such a problem occurs, patients will likely require anticoagulation (blood-thinning) medication to prevent more clots from forming and ending up in their lungs. Depending on the size and extent of a pulmonary embolus, this problem can be mild or life threatening.