SUBTOTAL AND TOTAL HEMIMANDIBULECTOMY

Hemimandibulectomy is a surgical procedure involving removal of part or all of the hemimandible. Subtotal hemimandibulectomy preserves the vertical ramus of the mandible and associated temporomandibular joint, while total hemimandibulectomy involves excision of the entire hemimandible. Rarely, more than 50% of the mandible is resected and this involves a subtotal or total hemimandibulectomy on one side and a portion of the mandible on the contralateral side. These procedures are indicated for extensive and malignant tumors of the mandible.

Subtotal Hemimandibulectomy

Total Hemimandibulectomy

> 50% Mandibular Resection

The overall complication rate following bilateral rostral mandibulectomy in dogs is 38%. The most common complications are mandibular drift and malocclusion (common), incisional swelling (common), tongue protrusion (common), wound dehiscence (8%-19%), ranula-like lesions (8%-14%), and short-term eating difficulties (up to 44% overall with 30%, 70%, 90%, and 97% of dogs returning to voluntary eating by day 1, 2, 3, and 4, respectively). The median time to return to voluntary eating is 2.5 days following hemimandibulectomy in dogs.

Complications are more frequently encountered in cats with 100% of cats having short-term complications and 84%-98% of cats having long-term complications. The most common complications are eating difficulties and/or dysphagia. Eating difficulties and/or dysphagia are seen in 74% of cats in the first 14 days and long-term in 53% of cats treated with hemimandibulectomy. Eating difficulties and/or dysphagia are seen in 83% of cats in both the short- long-term in cats treated with resectionm of > 50% of the mandible. Ptyalism (excessive drooling) is reported in 37% of cats following hemimandibulectomy and 83% of cats following resection of > 50% of the mandible; and this was persistent in 21% and 33% of these cats, respectively. Grooming difficulties are reported in 26% of cats following hemimandibulectomy and 17% of cats following resection of > 50% of the mandible. Tongue protrusion is reported in 42% of cats following hemimandibulectomy and 50% of cats following resection of > 50% of the mandible. Mandibular drift, with subsequent malocclusion and trauma to the overlying hard palate, is reported in 16% of cats following hemimandibulectomy and 33% of cats following resection of > 50% of the mandible. Despite this high complication rate and need for supplemental nutrition via a feeding tube postoperatively, 83% of owners were satisfied with the outcome following mandibulectomy in their cats.