It is the first case report of a mandibular ramus osteomyelitis in a 6 month old cat, associated with pre-operative extra articular TMJ partial ankylosis, ROM and mandibular extension reduction (2cm). The surgery was performed removing the ramus in total via a zygomatic approach and preserving the TMJ. Culture and sensitivity evidentiated that the osteomyelitis (histologically confirmed) was due to Pseudomonas, that was treated with dedicated fluoroquinolones. Immediate pain relief and normal ROM of the TMJ and mandibular extension (4.5cm) was achieved in the immediate post-op, with the cat normally eating in few hours. CT in the immediate post-op showed successful removal of the infected bone as planned. Today I had finally the chance to perform a 2 months post operative CT, that evidentiated nearly complete regrowth of a normal mandibular ramus, and optimal clinical status of the cat at 8 months, in absence of complications. A new TC is due in 6 months. It is the first case report of such type of osteomyelitis in a cat, and it is the first time Pseudomonas is isolated as etiological cause for such osteomyelitis in the maxillofacial district of a cat. A complete and more appropriate abstract will be sent to Dr. Ana Rejec in few days, as agreed.