A neutered male rescued Shih Tzu of unknown age was brought to the referring veterinarian for a wellness evaluation. Oral
examination showed generalized severe tartar, halitosis, gingivitis and gingival recession.
Dr. Brett Beckman
Full-mouth radiographs revealed generalized stage IV periodontal disease. Both mandibles were severely affected adjacent to
the molar and premolar teeth. The referring veterinarian successfully performed multiple extractions (Photo 1). However, a
bony swelling on the ventral aspect of the mandible adjacent to the mesial aspect of the right mandibular first molar (tooth
409) prompted referral to my facility.
Photo 1: A radiograph of the left mandible after extraction of the premolars and molars by the referring veterinarian. (PHOTOS
COURTESY OF DR. BECKMAN)
An appointment was scheduled for later that month.
According to the clients, the patient did well three days after the extractions by the referring veterinarian. But on the
third day, he escaped and roamed unattended outdoors for a few hours before he was found. For the next two days he was anorectic.
The patient was brought back to the referring hospital, and a right mandibular fracture was found in the region of the previously
noted swelling. Referral was then expedited to our next available appointment.
Patient evaluation and diagnosis
On examination of the patient at our practice, palpation was consistent with a right midbody mandibular fracture. Bony enlargement
was present on the lingual and vestibular portion of the mandible surrounding the fracture site. The patient would not tolerate
oral examination and was anesthetized for a dental radiographic examination, which confirmed a right mandibular fracture bisecting
the alveolus of the mesial root of the first molar (Photo 2).
Photo 2: A radiograph of the right mandible demonstrating the fracture at the time of presentation to our practice.
Neoplasia is always a consideration, but the radiographs suggested a characteristic infrabony defect mesial to the mesial
root of tooth 409 at the fracture site characteristic of a periodontal cause. Periodontal bone loss was severe in all four
quadrants, further supporting a periodontal etiology. It is likely this patient had a pathologic mandibular fracture in the
past with partial healing and stabilization. Concurrent focal osteomyelitis may also have played a role. In any case, this
would create an ideal environment for refracture.
Edentulous pathologic mandibular fractures generally pose a challenge. In this case, tooth 409 required extraction before
fracture repair, because leaving this tooth within the fracture line would beg failure. Traditional bone plates are usually
poor options because of their intrusion on the mandibular canal and the presence of compromised bone density. External coaptation
is generally futile for similar reasons. Interdental wiring or acrylic splints can be used to form the basis of primary repair
only if adequate dentition is present surrounding the fracture site. Without teeth, creative measures are often needed to
avoid mandibulectomy. In this case, a novel, malleable, titanium mesh material was chosen for primary repair.