The incidence of periodontal disease in dogs is extremely high, with some studies reporting that approximately 80% of dogs over the age of two years are affected. Periodontal disease, commonly known as gum disease, refers to inflammation that occurs within the supporting structures of the teeth. These structures are collectively called the periodontium and they include the gingiva (gums), the periodontal ligaments (attaching the tooth to the bone of the jaw) and the alveolar bone (the bony socket of the jaw).
The main factor leading to the development of periodontal disease is the accumulation of dental plaque on the surface of the teeth. Plaque is an invisible, sticky layer that is made up of bacteria, oral debris, cells and components of saliva. It can be removed by brushing, but accumulates again rapidly after cleaning. If plaque is not removed, it becomes mineralised and turns to calculus (commonly known as tartar) through the effect of calcium salts from saliva. Calculus is a hard, brown, chalky covering on the tooth, which is difficult to remove other than by professional means. It acts as a rough surface, facilitating and enhancing further plaque development on top of it.
Gingivitis is inflammation of the gum tissue caused by plaque on the tooth. It appears as a red line on the edge of the gum, which bleeds easily if touched. Gingivitis is the earliest sign of periodontal disease and is a reversible condition if treated. Gingivitis does not affect the periodontal ligament or the alveolar bone. However, if it is not treated, it can develop into Periodontitis, which is the inflammation of the other support structures of the tooth. The gum recedes, allowing bacteria to cause inflammatory reactions that lead to the destruction of the periodontal ligament and the alveolar bone. This destruction is irreversible and the tooth's support structure is permanently lost, causing the tooth to become loose and ultimately to fall out. Periodontitis usually occurs after a prolonged period of gingivitis and plaque accumulation.
Bad breath is the most common sign of periodontal disease that is noticed by owners. There may also be excessive salivation/drooling and the presence of blood in the mouth. The dog may have pain or difficulty in eating, and may eat more slowly or using only one side of the mouth. The pet may also shy away when touched in the mouth area. Poor dental health is a major cause of discomfort and general ill health in dogs and can lead to irritability and depression as a result of the pain. Due to the presence of the oral infection, tonsillitis and pharyngitis can also occur. As well as the localised effects of periodontal disease, studies have shown that it also has an impact on the health of distant organs. Bacteria in the mouth gain access to the bloodstream and are carried elsewhere in the body. It has been found that dogs with severe periodontal disease have more microscopic damage in their heart, liver and kidneys than in the case of dogs with less severe periodontal disease.
Dental caries, also known as tooth decay or cavities in humans, has a much lower incidence in dogs than it does in humans. It occurs when bacteria stick to the surface of the tooth and produce acids to dissolve it using sugar in the saliva. In dogs, it mostly occurs on the molar teeth. Research has shown that the types of bacteria present in human mouths differ from those in the canine mouth, particularly in the case of streptococcal species. This is likely to be an explanation for the low incidence of dental caries in dogs.
Dental Home Care
To regularly practise an oral hygiene programme at home can greatly improve a dog's oral health. A number of methods exist, each with the goal of preventing or controlling periodontal disease by reducing plaque accumulation and preventing its mineralisation into calculus/tartar.
The most effective way to reduce the risk of periodontal disease and to maintain oral health is to regularly brush the dog's teeth. This method is considered the "Gold Standard" of preventative dental care as plaque is easily disrupted by the mechanical action of brushing. Ideally, dogs should be introduced to tooth brushing when they are puppies, but the procedure can also be introduced to older dogs.
There are specially designed canine toothbrushes available, although a human toothbrush could also be used. Some dogs prefer the use of a finger brush. It is extremely important never to use human toothpastes as they are not meant to be swallowed and they also contain foaming agents and other ingredients that will not be tolerated by dogs. Canine toothpastes often have a meaty flavour, which helps in their acceptability. When training a dog to have his teeth brushed, patience is required. The approach should be gradual and should start at first for a few days by getting the dog accustomed to being handled around the head and mouth, using praise and treats as rewards. Initially, the brush should be dipped into the dog's favourite food or something with a meat flavour, before progressing onto canine toothpastes.
Insert the brush between the lips and gently move the bristles against the teeth and gums, holding the brush at an angle of approximately 45 degrees. Brushing is usually required only on the buccal (outside) surface of the teeth as the dog's long, flexible tongue cleans the lingual (inside) surface quite well. In order to be most effective, the procedure should be carried out daily. However, even to brush the teeth three or four times per week will have a very beneficial impact on oral health.
Another method that can be used in an oral care programme involves a more passive approach, which does not require the owner to handle the mouth. This is the use of dental chews. Chews can have an effect in the reduction of plaque and calculus. Through their mechanical action, they can help to reduce plaque accumulation on the tooth surface. In addition, the act of chewing in itself also has an effect because it causes more saliva to be produced. This salivary flow assists in the protection of the teeth by physically bathing the structures of the mouth, washing away bacteria and binding iron, which is needed for bacterial growth. Saliva contains antibacterial substances and enzymes, which are involved in the oral defence mechanisms, helping to reduce plaque accumulation.
Regular use of dental chews (once daily) can be a useful way to maintain dental health, but owners should also consider the dog's daily food ration and take account of the calories contained in the dental chew. It should also be noted that some products on the market are too hard and may cause the fracture of teeth. In order to prevent such fractures, the chosen product should be pliable and not as strong as tooth enamel.