Animals, just like humans, can suffer from oral and dental diseases that can affect their overall health. Some of these diseases such as autoimmune diseases, cancer, and hereditary or congenital conditions cannot be prevented. Many conditions such as periodontal disease and gingivitis are very much preventable! You’ve probably heard your veterinary team talk about dental health, dental food and treats, and ways to improve dental and oral health. But WHY is it so important? Having good oral hygiene is extremely important for our pets because, like us, the consequences of dental disease can reach much farther than their teeth. This blog post will teach you about some complications of dental and oral cavity disease and how to recognize them. You can also check out our other posts Tip to Brushing Your Pet’s Teeth and A Healthy Mouth Makes a Happy Pet to read about what you can do to prevent them!
Periodontal disease can be defined as infection and inflammation affecting the structures surrounding teeth, including the gums, periodontal ligament, and alveolar bone making up the tooth socket. Periodontal disease starts below the gum line with an accumulation of plaque made up of food debris and bacteria. After approximately 36 hours this plaque starts to calcify as a result of byproducts of bacterial metabolism and components of the saliva and hardens into tartar. Brushing your pet’s teeth can remove plaque, but once it hardens into tartar, it is much more difficult to remove. Bacteria live in plaque and tartar and triggers inflammation of the gums, known as gingivitis because the immune system recognizes the bacteria as foreign. Prolonged and severe infection and gingivitis cause gingival recession, which exposes the tooth roots, periodontal ligaments, and the bone. When these structures are affected the teeth become loose and can eventually fall out.
You’ve probably heard of the more common and obvious results of periodontal disease such as tooth sensitivity and pain. Which our pets hide extremely well – look for excessive drooling, dropping food, or avoiding certain toys, bleeding gums, and bad breath. Keep reading below to learn about some of the less well-known possible consequences of periodontal disease!
Tooth Root Abscesses
Many of the bacteria in the oral cavity are anaerobic bacteria, meaning that they do best in environments without oxygen – such as the area below the gumline. These bacteria can spread along the tooth root under the gums, and given the right conditions can result in a tooth root abscess – a pocket of bacteria and puss at the base of the tooth.
Tooth root abscesses are extremely painful and can cause pets to stop eating their food. They cause compression of surrounding tissues and sinuses and can cause swelling of the gums, lips and sometimes the entire affected side of the face. The eye above the affected tooth can also be compressed by surrounding tissue and become swollen shut – this generally resolves with treatment and the eye itself is typically not affected. Sometimes owners observe their pet rubbing the side of its face as this swelling is uncomfortable. Draining tracts can occasionally be seen when the abscess has ruptured inside the oral cavity and pus will be noted leaking around the tooth – this is associated with a foul odour.
Treatment of tooth root abscesses typically requires surgical extraction of the affected tooth as there is no way to fully rid the tooth of the bacteria from our position above the gumline. Antibiotics and anti-inflammatories can be used to treat the infection temporarily, and this is often done prior to dental cleanings and extractions, however, without removal of the tooth, the infection usually recurs.
Pathologic Jaw Fractures
When fractures occur as a result of a pre-existing bone disease that weakened the structure of the bone, it is known as a pathologic fracture. Pathologic jaw fractures are not uncommon in cats and small dogs with advanced periodontal disease. As discussed above, prolonged and severe gingivitis causes a gingival recession and periodontal disease which eventually results in the exposure of bone, either directly or after tooth becomes mobile or are lost completely. The same bacteria that cause gingivitis, periodontal disease, and tooth root abscesses can also invade the bone causing osteomyelitis. Osteomyelitis, or the inflammation and infection of the bone, weakens the structure of the bone marrow and cortex and causes it to fracture more easily.
In small breed dogs and cats which have very narrow lower jaw bones, the area of bone surrounding the teeth can become sufficiently diseased that the jaw bone can fracture during routine activities such as eating or playing. Fractures usually occur around the canine teeth, as these teeth have the largest sockets and thus the largest area of bone is exposed to bacteria and can become diseased. In these small animals the large roots of the canine teeth also strengthen and provide structure to the lower jaw to some degree, so if these teeth become loose or fall it, this will also weaken the jaw. Of course, these types of fractures can occur in large breed dogs, but they are much less common than in their tiny counterparts.
The treatment for pathologic bone fractures is multimodal: the fracture itself needs to be addressed, which often involves wiring or plating the jaw, and the underlying diseases that weakened the bones need to be treated. Again, antibiotics and anti-inflammatories are used to treat infection and inflammation, but the key to successful treatment is a full dental cleaning and extraction of diseased teeth.
Other Infections and Abscesses
When periodontal disease is present, new blood vessels are formed in the gums and the blood flow to the infected areas around plaque and tartar increases – this is one of the bodies protective mechanisms to help fight infection. However, this inflammation can also result in bacteremia, or the presence of bacteria in the blood, and hematogenous spread of bacteria through the blood. This can cause infections in other parts of the body. More common sites of hematogenous bacterial infections are the heart, lungs, kidneys, liver, joints, and urinary tract.
Bacterial endocarditis, a bacterial infection affecting the inner lining of the heart, is commonly seen in dogs with dental disease. According to the World Small Animal Veterinary Association, the risk of endocarditis is about six times higher in dogs with stage three periodontal disease than for dogs without. Often this infection is subclinical with the only clinical sign being intermittent lethargy, and it can go on undetected for months resulting in permanent damage to the heart. As endocarditis becomes more chronic, it causes scar tissue to form along the inner lining of the heart, a change known as myxomatous degeneration reduces the pumping efficiency of the heart. When this scar tissue forms on the heart valves it can result in the development of a heart murmur, which is often one of the first signs of heart disease. Over time this disease can result in congestive heart failure, and medications to help the heart function may be required.
Weight Loss, Malnourishment and Poor Hair Coat
Dental disease is invariably accompanied by oral pain. This pain can be caused by gingivitis, abscesses, cavities, fractured or loose teeth, or bone disease below the gumline. Our pets will often develop an aversion to things that cause them pain, and when their mouth is painful that means that they can stop eating, grooming, and playing. Pets with moderate to severe dental disease often are underweight or have rapid weight loss as the act of eating becomes more and more painful. As a result of decreased food intake, they can also become malnourished, leading to other health problems including heart disease, liver disease, and gastrointestinal disease among others. A poor hair coat results from the lack of grooming, as well as malnourishment. Occasionally animals will develop an ear, eye, respiratory, or urinary tract infections as a result of poor grooming behaviours.
Antibiotics and anti-inflammatories can be used in some cases to reduce the severity of dental disease temporarily, and feeding a soft diet of canned food or moistened kibble reduces the pain associated with eating. However, dental disease always progresses and eventually some pets will stop eating soft food. Dental cleanings and extractions of diseased teeth are the treatment of choice.
Dogs and cats with diabetes mellitus tend to have higher grade periodontal disease, and each condition can perpetuate the other. Inflammation and infection associated with periodontal disease can affect blood sugar metabolism and decreases the body’s sensitivity to insulin, which can increase the risk of developing diabetes and also makes regulation of diabetes more difficult. Conversely, blood sugar levels in patients with diabetes are elevated, which provides a larger food source for bacteria that cause periodontal disease. The cause and effect relationship between the two diseases has not been fully established yet, but what we do know is that once the oral health is addressed blood sugar levels are often easier to regulate.
Written by: Dr. Brittni Milligan. Veterinarian