Dental Disorders of Dogs

In gingivitis, the gums become inflamed because of bacterial plaque, but the ligaments and bone are not yet affected. The gums change in color from coral-pink to red or purple, and the edge of the gum swells. The gums tend to bleed on contact. Bad breath is common. Gingivitis can be reversed with proper tooth cleaning but, if untreated, may lead to periodontitis (see Dental Disorders of Dogs : Periodontitis).

Gingivitis usually can be treated by thorough professional cleaning of the teeth. This should include cleaning below the gum line. If gingivitis does not improve, the dog should be examined again in case more extensive cleaning is required. When cleanings are completed, your veterinarian may apply a sealant to the teeth to prevent bacterial buildup and improve healing. Dogs that do not respond to treatment should be evaluated for other disease such as immune system problems and diabetes. Gingivitis will reoccur if the teeth are not kept clean and free of plaque. Therefore, at-home oral hygiene methods such as brushing as well as regular cleanings by your veterinarian are important.

In periodontitis, the tissue damage is more severe and includes the gums, ligaments, and bone. It usually is seen after years of development of plaque, tartar, and gingivitis. It is irreversible and results in permanent loss of tooth support. Small-breed dogs usually experience more problems with periodontitis than large-breed dogs. Dogs that have a regular diet of hard kibble develop fewer problems due to the mechanical cleaning effect on the teeth as the food is chewed. Back teeth are affected more often than front teeth. The upper teeth are affected more severely than the lower teeth, and the cheek surfaces of the teeth have more disease than the surfaces near the tongue. Gingivitis is often first noticed at about 2 years of age but improves if treated. Periodontitis usually begins at 4 to 6 years of age and, if untreated, progresses to tooth loss.

Periodontitis is treated with thorough professional cleaning above and below the gum line. In some cases, surgery will be needed to gain access to the root surface for cleaning. Teeth can generally be saved until they have lost about 66% of their bone support from one or more of their roots. Your veterinarian can determine the extent of bone support loss by taking x-rays of the jaws. These are usually recommended as a normal part of periodontal disease diagnosis and treatment planning.

If your dog has been treated for periodontitis, you will need to continue oral hygiene care at home. Follow your veterinarian’s instructions, which might include daily toothbrushing, dietary changes, plaque prevention gel, and oral rinses. Regular (every 6 months to 1 year) preventive cleanings will help to avoid relapse and prevent further bone loss.

The most important thing to remember is that gum disease will not develop around clean teeth. At-home methods to keep your pet’s teeth clean, such as toothbrushing and diet, along with regular dental examinations, are the best ways to help prevent gum disease. Your veterinarian might also apply a barrier sealant or recommend a plaque prevention gel. These products form a barrier to repel bacteria-laden saliva from the tooth surface and prevent plaque formation on teeth. In the future, vaccines may be available to help prevent this disease.

Proper growth and development of the mouth and teeth depend on a series of events that must occur in proper sequence or longterm complications will occur. Early detection and intervention is the best way to prevent more serious problems. Dental development can be divided into 3 stages, each of which can have its own set of problems that require inspection by a veterinarian. Stage 1 is from 0 to 16 weeks of age, Stage 2 is from 16 weeks to 7 months of age, and Stage 3 is from 7 months to 1½ years of age.

Stage 1: Puppies are born with relatively long upper jaws (“overbite”), which allow them to nurse. As the dog grows and begins to eat solid food, the lower jaw goes through a growth spurt. If certain of the lower baby teeth come in before the growth spurt, they can get caught behind the upper teeth and prevent the lower jaw from developing to its proper length. If your veterinarian notices this pattern in a puppy, he or she will probably recommend removing several lower baby (deciduous) teeth. If this is done, the lower jaw will have the opportunity to reach its full length, thus averting problems with the permanent teeth. Some dogs will naturally develop a significant overbite, whether or not tooth extraction is performed.

The reverse situation can also occur. In these cases, the lower jaw grows faster than usual and becomes too long for the upper jaw, producing an “underbite.” This condition can be detected as early as 8 weeks of age. Again, certain teeth from the upper jaw may become caught behind those of the lower jaw, preventing proper growth of the upper jaw. The usual treatment is to extract several upper baby teeth. Early detection and correction of such problems will produce the best longterm results.

Other congenital and developmental problems in Stage 1 that may require treatment include extra teeth (which should be extracted only if they are causing problems) or incorrect position of a baby tooth, which should be extracted if it is interfering with other teeth. If jaw growth is different between the left and right sides, teeth may be extracted from the less-developed side. This procedure provides the best opportunity for the uneven growth to correct itself.

Stage 2: The most important problem that can occur during this stage is the retention of baby teeth. Normally, shedding begins around 14 weeks of age with the loss of the upper central incisors. For the next 3 months, the baby teeth are replaced with permanent teeth. Additional permanent teeth that complete the dog’s tooth pattern also erupt during this stage. If the baby teeth are not lost at the time the corresponding permanent teeth are coming in, abnormal tooth position and bite may result. If retained baby teeth are removed by a veterinarian as soon as they are noticed; complications can usually be prevented from occurring later on.

Another developmental problem noted in Stage 2 is abnormal positioning (tilting) of lower or upper canine teeth. Depending on the specific situation and age of the dog, orthodontic treatment (that is, “braces” for your pet) can be used to align teeth in their correct positions. Tilting of the upper canines typically is seen in Shetland Sheepdogs, although it has been reported in many other small breeds. Overbite is sometimes noticed during this stage and can be treated with a special plate fitted in the mouth. In more severe cases, tooth shortening or extractions might be necessary.

Stage 3: Additional types of incorrect tooth placement can occur during this stage of your pet’s growth. Treatment, if necessary, may include orthodontic treatment or tooth extraction. Crowding of teeth is resolved by extracting one or more teeth. Likewise, teeth that are significantly rotated, as are often found in flat-faced (brachycephalic) breeds, are usually removed.

During the development of tooth enamel on both baby and permanent teeth, fevers and the deposition of chemicals within the tooth may cause permanent damage. The canine distemper virus is especially damaging because it both attacks the enamel-producing cells of the teeth and causes a fever. This results in tooth enamel that is thinner than normal. Other fever-causing diseases may result in enamel that does not develop properly and is weaker than normal. Severe malnutrition in young dogs may result in enamel defects. Enamel defects in isolated teeth are most likely the result of trauma or infection. Often, the infections in fractured baby teeth affect the enamel of the permanent teeth that come in behind them. Enamel defects may also be inherited, especially in Siberian Huskies.

Treatment of these conditions can include bonding of synthetic materials to the teeth, fluoride treatment, and frequent dental preventive care.