Interesting case to share. A six month old kitten presented with an inability to open the mouth more than a 3 millimiters. The referring veterinarian tried under anesthesia but could only get it opened to 5 mm. At the time the tentative dx was TM ankylosis and a recommendation for the owners to get a CAT scan then surgery.

Image 1.

The cat scan of the skull revealed the left TMJ within normal limits and the right severly ankylosed. The mandibular fossa of the tmporal bone was deformed as was the articular process of the mandible.

Image 2.

The diagnosis of right temporomandublar joint ankylosis with cranial luxation fo the joint was made. A tracheostomy tube was placed ( for the CAT scan). It was impossible to open the mouth under general anesthesia. The right TMJ was approached by skin incision along he ventral border of the posterior half of the zygomatic arch. Reactive new bone and the condyle process were removed with dental bur and rongeurs. Part of the coronid process was fused to the temporal bone and was resected allowing the jaw to open with full range of motion. The cat made an uneventful recovery and won't stop eating according to the owners. Following is the image immediately after surgery.

Image 3.

Refer to associated Dentistry Board discussion