MANDIBULAR PROSTHESIS

Reconstruction of the mandible following various mandibulectomy procedures has been an area of interest in both cats and dogs. There are six published case reports on reconstruction of segmental mandibular defects in dogs with autografts (rib or ulna, and with or without recombinant human bone morphogenetic protein 2 [rhBMP-2]) or absorpbable compression resistant matrix with rhBMP-2. However, dogs typically have few complications following mandibulectomy and the need to reconstruct a segmental defect is really aimed at preventing mandibular drift which is usually a cosmetic rather than a functional problem.

In contrast, cats have a high complication rate following any type of mandibulectomy. Eating difficulties are seen in 72% cats and the median time to return to voluntary eating is 4 weeks following surgery, which means these cats require supplemental nutrition via either a esophagostomy or gastrostomy tube until voluntary eating returns. Furtnerore, 12% of cats never eat again. There are a number of challenges with reconstruction of a feline mandible, especially as total hemimandibulectomy rather than segmental mandibulectomy is often required due to the large size of oral tumors in cats relative to the size of their mandible. There is one report of a cat treated with mandibular reconstruction (from Alta Vista Animal Hospital, and featured on David Suzuki's The Nature of Things). A segmental mandibulectomy was reconstructed with a custom designed and 3D-printed titanium prosthesis. While this is only a single case, the cat began eating coluntarily within 2 days of surgery and continues to do well 12 months postoperatively.

Preoperative CT Scan and Computer-Aided Design and 3D Printing of the Customized Prosthesis