Dental surgery resolves feline bilateral TMJ dysplasia

Maxillofacial surgeon unlocks rare feline TMJ problem

A cat’s bilateral temporomandibular joint (TMJ) dysplasia has been resolved following complex surgery performed at Davies Veterinary Specialists.

Dexy, a 12-year-old female cat suffered with an intermittent locking jaw, which was usually triggered by her yawning or grooming herself. She was diagnosed with bilateral TMJ dysplasia, which is relatively rare in cats and was referred to the Dental and Maxillofacial Surgery Clinic at Davies for treatment.

“Dexy was in distress every time her jaw locked, and she couldn’t eat or drink,” said Dr José Ruiz, Head of Dentistry and Maxillofacial Surgery at Davies. “The only available treatment for this problem is surgery: in order to prevent the mandibles from locking, due to the abnormal elasticity in the joint’s capsule and ligament, we needed to remove some bone from her cheek and jawbones – known as the zygomatic arch and mandible.”

The anaesthesia team performed a bilateral trigeminal nerve block to reduce any possible pain during and after the surgery with excellent results. Dr Ruiz then approached the zygomatic arch at its ventral aspect.

An incision was made over Dexy’s cheekbone in order to access and cut it. The bone-cutting was performed using an instrument that when vibrating can cut bone but not soft tissues, thus preventing any trauma to blood vessels or nerve structures. The top part of the mandible was also cut to prevent it from locking on the remaining cheekbone.

“I reflected the skin dorsally and elevated subperiosteally the insertion of the masseter muscle to the ventral aspect of the zygomatic arch,” explained Dr Ruiz. “Using a piezoeIectric surgery handpiece, I resected the ventral two-thirds of the zygomatic arch in a half-moon fashion and separated the masseter muscle fibres along their long axis, exposed the coronoid process and resected its dorsal two thirds. I then repeated the process on the opposite side.”

Dexy recovered very well and she was discharged 24 hours after the procedure.

Click here to find out more about the Dental and Maxillofacial Surgery Clinic at Davies.