The mandible, commonly known as the jawbone, forms the structural foundation of the lower face and plays a role in speaking, swallowing, and chewing. Surgery to remove a portion of this bone is called a mandibulectomy or mandibular resection. This procedure is a treatment option for serious conditions, most often to remove cancerous tumors in the mouth or throat. Mandibulectomy is a specialized oral surgery requiring careful planning to remove diseased tissue while preserving the patient’s function and minimizing bone removal.
Defining the Marginal Approach
A marginal mandibulectomy is a specialized mandibular resection that removes only a specific portion of the jawbone while maintaining its structural integrity. This approach involves removing the upper rim, or the inner or outer layer of the mandible, without cutting through the full vertical height of the bone. Surgeons remove the alveolar process (the part of the jawbone that holds the teeth) or the cortical bone layer closest to the tumor.
The defining characteristic of the marginal approach is the preservation of the mandible’s lower border, known as the basal bone. This bone-sparing technique avoids interrupting the continuity of the jawbone. Maintaining continuity ensures the jaw retains its structural support, which helps prevent functional collapse or facial asymmetry.
The marginal procedure is often contrasted with a segmental mandibulectomy, which is a more extensive surgery. A segmental mandibulectomy requires removing a full-thickness segment of the jawbone, interrupting the jaw’s continuity. This radical procedure is typically required when a tumor has deeply infiltrated the bone.
Because the marginal approach preserves the structural arch of the jawbone, it generally eliminates the need for immediate, complex bone reconstruction using tissue grafts. This minimizes surgical time and reduces the associated risks and donor site morbidity that accompany reconstructive procedures. The marginal mandibulectomy offers an oncologically sound alternative that preserves the long-term cosmetic and functional integrity of the jaw for carefully selected patients.
Primary Indications for Surgery
The decision to perform a marginal mandibulectomy is based on specific criteria related to the tumor’s size and depth of invasion into the jawbone. This approach is reserved for small, localized tumors, such as early-stage squamous cell carcinoma, that lie near the mandible. The primary indication is that the tumor must abut the jawbone or have only minimally eroded the outer cortical layer of the bone.
The tumor must not have infiltrated the medullary bone, which is the spongy, central part of the jawbone. If pre-operative imaging or biopsy confirms deep invasion, a more extensive segmental resection is necessary to ensure complete tumor removal. Surgical planning relies on high-resolution imaging techniques, such as computed tomography (CT) scans and magnetic resonance imaging (MRI), to precisely map the extent of bone involvement.
These scans help determine if the tumor is lying against the bone surface or penetrating deeper layers. The guiding principle of all cancer surgery is to achieve “clear margins,” meaning the complete removal of the tumor along with a safety margin of healthy tissue. A marginal mandibulectomy is appropriate when a clear margin can be achieved by removing only the rim of the bone.
The Procedure and Immediate Post-Op Care
The marginal mandibulectomy is performed under general anesthesia and may be approached in one of two ways, depending on the tumor’s location and size. Smaller, more accessible lesions can be performed intraorally, or entirely through the mouth. Larger or more complex lesions may require an external incision, often made in the neck, to provide necessary visibility and access for the resection. The surgeon carefully removes the tumor and the adjacent rim of bone using specialized surgical instruments, ensuring the lower border of the mandible remains intact.
Following the bone and soft tissue resection, the surgical site is closed, often using a soft tissue flap to cover the exposed bone. The procedure typically takes several hours, depending on the complexity of the tumor and any associated soft tissue reconstruction.
The immediate post-operative period begins in the hospital, with a typical stay lasting between three and seven days. Initial care focuses on pain management, controlled through a combination of medications administered intravenously or orally. Patients are closely monitored for complications such as swelling, bleeding, or fluid collections, which may necessitate the use of temporary surgical drains placed near the incision site.
Due to the surgery and resulting swelling, patients often experience temporary difficulty with mouth opening, known as trismus. To ensure adequate nutrition during this initial healing phase, a liquid or soft diet is required. Some patients may temporarily need a nasogastric feeding tube placed through the nose.
Long-Term Recovery and Functional Outcomes
The recovery period after a marginal mandibulectomy extends beyond the hospital stay, with patients transitioning home to continue their healing process. The progression of the diet is a primary focus of the early recovery period, moving from an initial liquid diet to soft, pureed foods, and gradually back to a normal consistency over several weeks. Patients are typically advised to limit strenuous activity for several weeks to allow the bone and soft tissues to fully heal.
One of the most favorable functional outcomes of the marginal approach is the general preservation of speech and swallowing capabilities. Because the main structural support of the jaw is maintained, the patient’s tongue and surrounding muscles retain their normal mechanical function to a greater degree compared to those who undergo a segmental resection. This preservation often means less intensive rehabilitation is needed.
While the structural continuity of the jaw is preserved, patients may still experience some temporary or long-term changes. Swelling and bruising gradually resolve, but minor alterations to the facial contour can occur, though these are typically far less noticeable than the changes resulting from a segmental resection. Dental rehabilitation, such as the fitting of prosthetics or the placement of dental implants, may be planned months after the initial surgery once the bone has fully stabilized.
Overall, the long-term prognosis for function is favorable, reflecting the bone-sparing nature of the marginal procedure. Patients who undergo this surgery generally return to a high quality of life with minimal long-term functional deficits related to chewing and speaking. The success of the procedure rests on careful patient selection, ensuring the tumor is fully removed while maximizing the preservation of the native jaw structure.