Periodontal disease is a major health problem which can result in pain, gingivitis (redness and swelling of the gums), tooth loss, systemic disease (e.g. cardiovascular and kidney disease) and, in humans, adverse pregnancy outcomes.
In adult pets, periodontal disease is commonly observed. In fact, it is estimated that eighty percent of dogs and seventy percent of cats have some kind of dental disease, as a result of infection and inflammation of the gums, bone and tissue surrounding and supporting the teeth, initiated by an overgrowth of bacteria in the gums.
Other than bad breath, there are few signs associated with early disease. With severe disease, dogs may exhibit excessive drooling, difficulty in eating and weight loss.
Periodontal disease is typically separated into two conditions: gingivitis, an inflammation of the gingiva, or gums, and periodontitis, an inflammation of the tissues that surround and support the teeth, which is classified into stages of severity.
The occurrence of periodontal disease has been reported to significantly increase with age and decrease with increasing body weight, suggesting that smaller breed dogs may be at greater risk than larger breed dogs. Furthermore, gingivitis has been associated with nutritional deficiencies of vitamins A, C, D and E, and the B vitamins folic acid, niacin, pantothenic acid and riboflavin.
The disease is often described as more prevalent, more severe and less likely to be treated by a veterinarian in dogs used for commercial breeding than for pet dogs or hobby breeding dogs.
Given the potential adverse health outcomes for dogs with periodontal disease, it is important for dog breeders, owners and caretakers to attend to preventive dental care and seek therapeutic interventions early.
Keeping up-to-date with current preventive care practices and therapeutic interventions that decrease the occurrence and severity of dental disease may help owners determine which interventions are most effective and practical for them.
Experts believe that periodontal disease is the most common disease of dogs and cats of any age. The American Veterinary Dental Society estimates that by the age of three, eighty percent of dogs and seventy percent of cats show signs of oral disease. Untreated periodontal disease is thought to lead to bacteremia (circulating bacteria in the blood stream), which can lead to significant liver, heart or kidney disease.
Greyhounds, as many owners know, commonly suffer from dental disease. Some Greyhounds have a hyperimmune (exaggerated) response to plaque and calculus which can result in severe inflammation inside the mouth itself (“chronic ulcerative paradental stomatitis”).
The process of dental disease can begin to take hold within just a few hours of a dental cleaning. A biofilm forms on the teeth which can then be colonized by bacteria.
If left undisturbed, this combination of biofilm and bacteria can adhere more strongly to the tooth and is known as plaque. Untreated plaque allows for deposition of salivary minerals and allows for formation of hardened calculus. Although calculus itself does not cause periodontal disease, it provides a safe environment for the bacteria that do.
Though common in the pet dog population, periodontal disease is nevertheless considered one of the most undertreated health conditions. As is the case with humans, daily brushing of the dog’s teeth is necessary, however it is not always practical, and owners often do not continue daily brushing.
The second best option for dental care at home is to feed approved dental diets (e.g. Hill’s t / d diet) and treats (e.g. CET enzymatic chews). Though it is widely believed that a dry kibble diet, as opposed to a wet or canned diet, decreases risk of periodontal disease, this has not been proven.
Furthermore, it is recommended that all dogs be evaluated at least once a year by a veterinarian to assess the need for a thorough dental cleaning under anesthesia.
Due to the costs associated with dental cleaning by a veterinarian, in addition to the perceived and real risks of anesthesia, many owners have sought alternative methods of maintaining dental health. These include anesthesia-free dentistry, termed non-professional dental scaling by the American Veterinary Dental College (AVDC).
Major welfare concerns are associated with non-professional scaling, including risk of injury, pain and discomfort to the dogs, in addition to improper and incomplete cleaning, as well as damage to the teeth. It is not known how common this practice is in both the dog breeding community as well as among pet owners.
Treating Periodontal Disease
Traditional treatment for dental disease has included dental chews, rinses, brushing, antibiotics, anti-inflammatories and dental cleanings. A traditional saying has always been “It is good to chew, it is better to rinse, and it is best to brush.”
Any treatment is best used daily to prevent the formation of plaque. One of the main advantages to brushing is that it disrupts the biofilm on the teeth. Research has shown that it takes much higher concentrations of anti-bacterial agents to kill the bacteria in an undisrupted biofilm.
More recently there have been a few advances in veterinary dentistry that have improved the quality of medicine that your pet can receive.
A new spin on an old treatment has been made by Virbac with their veterinary dental rinse and gel. Both contain the active ingredient Chlorhexidene in a microencapsulated form which allows the chlorhexidene to bind to the gums and gingiva resulting in a prolonged duration of effect.
Merial’s OraVet Healthcare system, released in 2004, is also used for the treatment of dental disease. OraVet is a biologically inert waxy polymer that binds electrostatically to the tooth surface and creates an invisible, physical barrier that prevents bacterial attachment to the teeth. This is a two-part system which requires both veterinary and home care.
The OraVet Barrier Sealant is applied as the last step of a dental cleaning in the veterinarian’s office, once the pet’s mouth is dried. Beginning two weeks after the dental cleaning, the OraVet Plaque Prevention Gel is applied by the owner once weekly.
The gel contains the same active ingredient as the OraVet Barrier Sealant, but in a less concentrated form that is easier to apply. The gel is odorless, tasteless and can normally be applied in less than sixty seconds.
Two studies were performed to evaluate the efficacy of this treatment. They have shown OraVet to decrease mean plaque scores by 24% – 42% and mean calculus scores by 47%.
Dental Radiography (X-Rays)
Though not new, X-rays are becoming more common in veterinary medicine. Dental radiography allows for evaluation of alveolar bone loss (around the tooth roots), abscesses, fractures, retained root tips, malformed teeth, resorptive root lesions and other abnormalities that cannot be seen with the naked eye.
It is often said that the crown of the tooth (the portion we can see) is “just the tip of the iceberg” (2/3 of the tooth lies beneath the gum line). The amount of pathology (disease) that can occur that is not apparent to the naked eye is amazing.
It is important to differentiate a dental radiography (X-ray) machine from a standard radiography machine. A standard radiography machine is not ideal for dental X-rays for several reasons.
To begin with, the focal film distance, angulation and collimation (these three things are adjusted to improve the quality of the radiographs) require very fine adjustments to take good dental radiographs and these cannot be easily adjusted with a standard X-ray machine.
Moreover, a standard radiography machine is rarely stored in the room where dental procedures are performed. Should dental X-rays become necessary, transporting the patient to the radiography room can be cumbersome and time consuming.
Finally, when a standard radiography machine is used, it is not possible to isolate dental structures which make interpretation of the radiographs difficult. Accurate dental radiographs can prevent unnecessary extractions and allow for more aggressive treatment of periodontal disease which may result in a better outcome for the patient.
Health Risks Associated with Periodontal Disease
Another major concern of periodontal disease is its association with an increased risk of developing other diseases resulting from bacteremia (bacteria in the blood).
Diseases that have been shown to be associated with periodontal disease include chronic bronchitis and heart, kidney and liver disease. The most commonly cited secondary organ system affected by periodontal disease is the cardiovascular system in both humans and dogs.
For example, in a study of 59,296 dogs, an association was found between the severity of periodontal disease and the risk of cardiovascular-related disease conditions. The study’s authors concluded that greater awareness and importance of canine dental health and routine preventive care would improve overall health.
Furthermore, the American Veterinary Dental Society warns dog owners “that oral bacteria will be filtered out by the kidney and liver, and can cause micro-abscesses within these organs. This leads to a decrease in function of these vital organs over time.”
Dental Health in Commercial Breeding Dogs
Commercial dog breeding facilities are often portrayed as maintaining dogs in substandard conditions relative to housing, sanitation and veterinary care. One area emphasized as being of notable concern is periodontal disease.
The Humane Society Veterinary Medical Association has observed that “severe periodontal disease is routinely seen in breeding stock… The dogs often have a painful, infected mouth with loose and missing teeth.” These concerns, if valid, would represent significant animal welfare problems.
However, no scientific evaluation of the prevalence or severity of periodontal disease in commercial breeding dogs or of management practices employed to address it, has been conducted to date.
Of particular concern to dog breeders and animal health professionals is the health of the puppies produced. Recent studies suggest that periodontal disease may induce inﬂammatory responses throughout the body that increase the risk of adverse pregnancy outcomes.
Studies in humans have suggested an association between periodontal disease and adverse pregnancy outcomes, such as low birth weight, premature babies, miscarriage and pre-eclampsia. Another study indicated that early dental disease during pregnancy can be regarded as an important risk factor for premature birth.
Anecdotally, dog breeders who have incorporated routine dental care into the management of their breeding dogs have reported increased litter size, decreased mortality rates, as well as healthier puppies. Yet, no scientific evaluations of the association between periodontal disease and pregnancy outcomes have yet been reported in dogs.
Periodontal disease affects large numbers of dogs, often resulting in pain and secondary diseases. While the prevalence and severity of dental disease in pet dogs has been well documented, such information about commercial breeding dogs is not currently available.
More research of this population is needed to identify risk factors, associated systemic diseases, effect on pregnancy outcomes and practical preventive care strategies that can be implemented to minimize dental disease and lead to further improvements in the health and welfare of all dogs.
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