A 10 year old male greyhound presented with a hard swelling of the right ventral mandible.  Please review this radiograph.  What is the most likely diagnosis?

Skull radiographs were obtained in addition to intraoral dental radiographs.  There is an increased lucency associate with the mesial root of the right mandibular first molar (tooth 409) and the roots and furcational bone of the right mandibular fourth premolar (tooth 408). A smooth periosteal reaction is present ventral to the region. No cortical changes are evident. The most likely diagnoses are osteomyelitis secondary to periodontal disease, or idiopathic osteomyelitis.

Please review these radiographs and add any further observations.

Diffusely irregular punctate lucencies with periosteal reaction is commonly seen with osteomyelitis.

Necrotic bone can be seen dorsal to the defect in this post extraction image, confined clinically to the lingual cortical bone.

A partial rim mandibulectomy was utilized to eliminate necrotic bone. A diamond bur was then used to contour the marginal bone. The inflamed gingiva and mucosa were excised. The right mandibular third premolar (tooth 407) was extracted to facilitate a tension free closure.

Soft tissue and bone removed from the defect were sent for histopathological evaluation.

Diagnosis: Osteomyelitis and bone necrosis.

30 days postoperative view