Fractures of Upper and Lower Jaw in Dogs

Your dog’s jaw has a mandible (lower jaw) and a maxilla (upper jaw) which can be fractured in an accident or other trauma. In contrast, there are some infections and other illnesses that can cause the bones in that area to weaken, leaving your dog susceptible to mandible or maxilla fractures. Some of these are periodontitis (gum disease), tumor, cyst, or a metabolic disease or disorder (i.e. hypocalcemia). The risk of a secondary infection is great, so it is very important to bring your dog to see the veterinarian no matter how mild the damage seems to be because there could be more damage inside that you cannot see. The vet will check your dog for other injuries that may not be easily visible, as the force to cause a jaw fracture is great so co-morbidities are common.

Fractures of the upper jaw and lower jaw (fracture of the mandible or maxilla) are commonly caused by trauma, such as being hit by a vehicle or a fall from a height. Fractures can also be a complication during dental treatment or from a disease or infection. Many mandibular fractures are open fractures (broken skin) and are at risk for infection, so it is essential to start antibiotics right away. Without immediate treatment, the infection can cause serious illness and may even be fatal.

• Pain in the jaw area
• Swelling in the facial area
• Drooling
• Whining
• Depression
• Scratching or rubbing at jaw
• Anxiety
• Broken teeth
• Mouth bleeding
• Blood in the nasal passages
• Unable to open and/or close the mouth
• Inability to eat
• Visible injury to face

 Types

• Open fractures refer to a fracture that includes bones or teeth that have broken through the skin
• Closed fractures are any fracture that does not break the skin
• Simple fracture refers to a single and clean break that is easy to line up and secure
• Comminuted fracture is when the bone is shattered, crushed, or broken into more than three parts

• Accident or trauma (i.e. hit by vehicle, animal abuse, fall from a great height)
• Animal bite
• Periodontitis
• Tumor
• Cyst
• Metabolic disease or disorder

Your veterinarian will first want to know your dog’s medical history and the details of the accident or trauma (if applicable). He will also need to know when the symptoms started, whether they have gotten worse, and whether your dog’s behavior has changed. The veterinarian will do a thorough physical examination, checking for other injuries and being sure to get your dog’s body temperature, blood pressure, and heart rate. He will need to run some tests to determine the extent of the damage and the possible cause if not known. These tests will include:

• Complete blood count (CBC)
• Blood chemistry panel
• Blood clotting test
• Urinalysis
• Glucose test (blood sugar level)
• Bacterial and/or fungal culture if an infection is present
• Digital radiographs (x-rays) of the jaw while your dog is sedated
• Digital radiographs (x-rays) of the head, neck, and abdomen

Depending on the results of these tests, your veterinarian may need to run some more tests, such as a CT scan, MRI, ultrasound or biopsy (if a tumor is discovered). In some instances, there may be the need for a referral to a canine dental professional.

Your veterinarian’s main goal is to repair your dog’s jaw to normal while keeping the natural alignment so eating and chewing are restored. The best choice of treatment for a simple closed mandible or maxilla fracture are intra oral splints with a wire base and reinforced with acrylic or composite material to hold the jaw in place while it heals. The splint can be bonded to the tooth crowns of the teeth on both sides of the fracture. This type of splinting is best because it gives a good stable base on the tension side of the break, which is the best place to create a proper alignment during healing. Healing should take about six to eight weeks as long as the jaw can be set at the proper bite position the first time. Your dog may also need a feeding tube to help him eat while the jaw fracture is healing. 

If your dog has an open or comminuted fracture, surgery is usually necessary to repair or replace the shattered bones. Depending on the extent of the injury, the surgery is almost always successful and healing time is about the same as with the splinted repair. If the fracture is caused by an underlying disease or disorder, the treatment and recovery can vary greatly, depending on the condition and severity.

Periodontitis

Gum disease requires dental treatment by a canine dental professional that usually includes a thorough cleaning and scaling of the teeth as well as removal of any damaged or infected teeth.

Tumor

A tumor will have to be removed and biopsied to determine if it is cancerous. If cancer is present, radiation treatments and chemotherapy will most often be necessary. The treatment will vary depending on the extent of the cancer.

Cysts

A cyst may or may not need to be removed, depending on whether the veterinarian thinks it may cause more damage to the jaw and surrounding tissues. 

Metabolic Disease or Disorder

A metabolic disease or disorder, such as hypocalcemia, will need to be treated after the fracture has been taken care of. The treatments are varied depending on the type and extent of the disease or disorder.

The recovery outlook for a mandible or maxilla fracture is very good depending on the cause and severity of the fracture. If the veterinarian is able to align the jaw, setting the fracture is usually a routine procedure that is highly successful. If your dog has an underlying disease or infection, the recovery depends on how bad it is and whether it can be treated or not. The most significant thing you can do for your dog is to follow the veterinarian’s instructions and be sure to go to any follow-up appointments even if your dog is better and you do not think it is necessary. It is always important to follow up.