The Impact of Diet on Oral Health

Dental calculus is a common problem in most domestic cats and dogs resulting from mineralization of dental plaque; plaque being composed primarily of food particles and bacteria. Studies have reported the existence of dental calculus in 86% of cats between the ages of 1-4 years and all cats 5 years of age and older.

A number of options are available to the pet owner to control and maintain the long term oral health of their pets. Oral hygiene practiced on a regular basis is the most effective approach. However, pets need to be conditioned to such procedures from an early age and few owners are compliant on a long term basis. As a result, most owners look to diet or chew treats as a simpler, more convenient, albeit less effective, means of achieving this goal.

Gingivitis, an inflammation of the gum, is reversible and manageable through routine plaque control. If untreated or uncontrolled, gingivitis may lead to periodontitis, an inflammation of the supporting periodontal tissues. Periodontitis may well be irreversible and requires vigorous therapy and plaque control to avoid further progression.

Although often associated with gingivitis and periodontal disease, dental calculus is not the primary causal factor. Both gingivitis and periodontal disease are a result of bacterial overgrowth in the gum tissue that surrounds each tooth. Because dental calculus is so hard due to its mineral content, it usually is not removed when a pet eats hard kibble. Although dental plaque is the primary cause of gingivitis, there are other contributing factors, such as calculus, age, genetics, breed, immune status and diet.

Numerous studies have demonstrated that feeding a regular dry diet alone, when compared to a canned diet, will reduce the rate of plaque and subsequent calculus formation. However, what is not thoroughly understood is whether this effect is due to the mild abrasive action of the diet, or the greater likelihood of canned food to become entrapped in the gum tissue, leading to greater accumulation of plaque.

Studies have shown that feeding a dry diet coated with sodium hexametaphosphate (a component of some pet toothpaste that acts as the calcium sequestrant) reduced calculus formation by 50 - 80% in dogs. A similar preventive effect was also shown in cats.

Other studies showed the regular use of rawhide chew strips resulted in a modest reduction of calculus formation, but when these treats were coated with sodium hexametaphosphate, again the results showed a significant calculus reduction.

It is not universally accepted, though, that removal of calculus alone is adequate to prevent gingivitis. The removal of bacteria-laden plaque prior to its calcification, however, does minimize gingivitis.

Such research reinforces the opinion that the accumulation of plaque and the impact on oral health can be impacted by the use of certain diets and chew treats alone. Reduction of gingivitis by such means in indeed encouraging, but the long term benefits in the prevention of periodontal disease needs further research.

Within hours of a professional dental cleaning, plaque begins to re-accumulate. Although the teeth may look cleaner, the bacterial counts are not being controlled, even with no obvious calculus present. To obtain long term oral health, oral bacteria must be controlled by minimizing plaque build-up. This is best achieved by veterinarians continuing to demonstrate brushing techniques and encouraging their clients to practice oral home care procedures on their pets from an early age.