Definition & Overview
A mandibulectomy is a surgical procedure wherein the mandible (jawbone), or a part of it, is removed. It is typically performed to treat oral and jaw cancer and involves removing cancerous tissue to stop it from spreading.
Who Should Undergo and Expected Results
Mandibulectomy is recommended when tumours, both benign and malignant, are found in the jawbone. Some examples are:
- Squamous cell carcinoma
- Odontoma – A type of tumour that targets the dental follicles
- Giant cell tumour
- Ewing tumour
- Multiple myeloma
- Metastatic tumours
- Osteoradionecrosis – Although not considered as a type of cancer, this condition can lead to significant deterioration of the mandibular region
These tumours may cause symptoms such as:
- Jaw pain or bone tenderness, which can affect a person’s ability to eat and chew
- Lumps on the jaw, usually appearing on the roof of the mouth or along the gum lines
- Swelling, which may occur inside the mouth, such as the palate or alveolar ridge, but can also be visible on one side of the face
- Unexplained mobility of teeth, or when teeth suddenly become loose or seem to shift positions
The treatment of jawbone tumours depends on the location and type of the tumour. However, when the tumour is on, near, or inside the jawbone, oncologists recommend its excision, in which case a mandibulectomy becomes necessary. During a partial mandibulectomy, the part of the lower jaw where the tumour has formed is removed, as well as some healthy tissue around it to make sure that no cancer cells are left behind.
In some cases, a mandibulectomy is followed by a free flap reconstruction wherein the part of the jaw that has been removed is replaced by combining metal plates, muscles, and skin or bone flaps taken from another part of the patient’s body. This is performed to restore the patient’s ability to speak, eat, chew, and swallow as well as the patient’s facial appearance to as close to normal as possible.
Depending on the scope of the procedure, patients may require additional cancer treatment following surgery or dental restoration if any teeth were affected by surgery.
How is the Procedure Performed?
As a major surgical procedure, mandibulectomy is performed under general anaesthesia and depending on the scope of surgery, may require several days of hospitalisation.
The specific manner in which the procedure is performed depends on whether it is marginal or segmental.
Marginal mandibulectomy – This is ideal for tumours that are near the jawbone but have not spread inside the mandible. The procedure is performed using a saw to remove the jawbone rim near where the tumour is located. Marginal mandibulectomy is not typically followed by a reconstruction procedure.
Segmental mandibulectomy – This is ideal for cancers that are inside the jawbone. For this procedure, the surgeon makes a cut through the full thickness of the mandible to remove a full segment of the jawbone. The procedure is typically followed by a partial reconstruction to restore the patient’s facial appearance as much as possible as well as his ability to chew and speak properly.
It is normal for surgeons to create an incision in the windpipe (tracheotomy) to prevent breathing obstruction during the procedure and to use drains to prevent the accumulation of fluid from the neck.
Meanwhile, the complexity and duration of the recovery process depend mainly on the extent of the surgery and whether a reconstruction was performed. In marginal cases, the patient may be allowed to go home after a few hours. However, in segmental cases, patients are typically required to stay in the hospital for as long as two weeks for close monitoring.
Possible Risks and Complications
Just like any invasive procedure, a mandibulectomy comes with numerous risks and possible complications, including the following:
- Bleeding and hematoma
- Wound infection
- Seroma – This occurs when body fluid collects in the neck after the drain has been removed. In some cases treatment is not necessary as the body eventually reabsorbs the fluid. If not, the fluid will be drained through needle aspiration.
- Salivary fistula
- Blood clots – Cancer patients have a heightened risk of blood clots, especially deep venous thrombosis, when undergoing any procedure. These clots can travel to the lungs, causing a life-threatening condition called pulmonary embolism. This complication is treated with anticoagulants (blood-thinning medication).
- Recurrence of tumours – Although mandibulectomy can remove the tumour, it does not guarantee against recurrences, which means the procedure has to be repeated if the tumour grows back in the future.
- Malocclusion – The procedure can cause the upper and lower teeth to shift position
- Flap failure – This refers to the surgery’s failure to re-establish proper blood flow leading to the flap
- Chest infection
It is also usual for patients to experience pain, numbness, and some challenges in speaking and swallowing particularly right after the procedure. Pain can be controlled through pain relief medications, whereas the numbness is expected to subside gradually over time. As for speech and swallowing problems, the patient may require the expertise of other specialists such as speech and language therapists.
Abdulai A. E. “Complete Spontaneous Bone Regeneration Following Partial Mandibulectomy.” Ghana Med J. 2012 Sep; 46(3):174-177. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3645154/
Goiato MC., Medeiros RA., Filho AJV., et al. “Prosthetic rehabilitation of a patient after a partial mandibulectomy.” Annals of Medicine & Surgery. http://www.annalsjournal.com/article/S2049-0801(15)00051-5/abstract
Snow GB., Kruisbrink JJ., van Slooten EA. “Reconstruction after mandibulectomy for Cancer.” Arch Otolaryngol. 1976; 102(4):207-2010. http://archotol.jamanetwork.com/article.aspx?articleid=606179