Making the most of dental health (Sponsored by Iams)

In 2011, more than 1,000 dog and cat owners participated in an online survey about their awareness of and behavior toward pet oral care.1 In that survey, only 20% of the owners of pets older than 3 years felt that their pet had dental disease. Unfortunately, these survey results do not correlate with the report recently released by Banfield, The Pet Hospital,2 in which more than 2.1 million dogs and 450,000 cats were evaluated by veterinary professionals. In that report, about 70% of dogs from 3 to 10 years old and 60% of cats from 3 to 10 years old were found to have dental tartar (calculus). Based on these findings and other similar studies, it is evident that there is a large population of pets with dental disease not recognized by their owners.

Combating dental disease: Understanding the players

Within minutes of a professional cleaning, plaque begins to form along the gingival margin. At the onset, the plaque, or biofilm, is composed primarily of bacteria. The early colonizing bacteria are not pathogenic but can, in some cases, initiate gingivitis. Soon other bacteria, yeast, food particles, sloughed epithelial cells, and salivary mucin join to form a soft film. Clinically, early plaque cannot be seen, but as the mass increases, it can be disclosed with dyes. Plaque cannot be easily removed with normal tongue action, with salivary flow, or by drinking water.

If undisturbed, the biofilm progresses subgingivally. As it moves under the gingiva and between the teeth, the environment changes. Anaerobic bacteria begin to populate the plaque, becoming the predominant species. Toxins produced by these bacteria initiate and promote gingival inflammation and periodontal disease. Bad breath (halitosis) becomes a consequence of plaque and the associated bacterial population.

Once established, plaque is transformed to tartar through the precipitation and binding of salivary mineral components, such as calcium. Tartar in dogs is composed primarily of calcium carbonate mixed with small amounts of calcium phosphates. Tartar is rough, compared with the smooth enamel, and provides a porous surface for depositing more plaque (Figure 1). This results in a continual cycle of plaque deposition and tartar formation. Tartar is covered with bacteria that play a role in accelerating periodontal disease by keeping the plaque in close contact with the gingival tissue.

Figures 1-4 (click to enlarge)

Periodontal disease is an inflammation and infection of the supporting structures of the teeth. Periodontal disease is a complex condition, and its expression depends on the interaction between bacteria and the host's immune response. There are several stages of the disease, based on severity. The first stage is gingivitis. Left untreated, gingivitis can lead to infection and inflammation of supporting tooth structures, including the periodontal ligament and alveolar bone. Loss of support causes tooth instability and tooth loss. Infection may even become systemic, affecting major organs.3

Many variables influence why some pets develop periodontal disease and others do not. Pets that are compromised by health conditions — such as diabetes, feline immunodeficiency virus (FIV), feline leukemia virus (FeLV), and autoimmune disease — are often predisposed to periodontal disease.4 Toy canine breeds are especially prone to periodontal disease. Small dogs have shorter tooth roots, allowing bacterial byproducts to destroy a greater percentage of the tooth support compared with larger breeds. Additionally, smaller breeds tend to live longer than larger breeds, which allows more time for the effects of periodontal disease to appear. Smaller dogs are also more prone to dental malocclusions. Crowding abnormalities decrease the normal self-cleaning process, predisposing the dog to periodontal disease (Figure 2).

Nutrition and dental health

A rational approach to diminishing the chance of a dog or cat developing periodontal disease is to decrease the accumulation of plaque and tartar. The gold standard for plaque control is daily tooth brushing (Figures 3 & 4). However, only a small percentage of owners brush their pet's teeth. Fortunately, there are other proven approaches to controlling plaque and tartar formation, including mechanical and non-mechanical management through diets and treats.

When daily tooth brushing is not possible, other mechanical means can be used to brush plaque from the tooth surface. Examples of such products include certain pet foods, flexible rubber chew toys, soluble dental chews, and rawhide products. With some of these products, the efficacy is limited because only the teeth in contact with the product — primarily the chewing teeth — will benefit from the brushing action.

Non-mechanical management of tartar accumulation includes compounds or natural ingredients that decrease the formation of plaque, the adhesion of plaque on the tooth surface, and the formation of tartar. One such compound is sodium hexametaphosphate (SHMP), which has demonstrated dental benefits by reducing tartar formation when applied to the outside of kibble (see sidebar: Sodium hexametaphosphate: Effective tartarreducing agent). The benefit extends to all teeth, not just those used for chewing and grinding. Some dental health products combine mechanical and non-mechanical management. This combination would appear to be the best of both worlds, brushing plaque from tooth surfaces and decreasing the mineralization of plaque into tartar.

Sodium hexametaphosphate: Effective tartar-reducing agent (click to enlarge)

Canine study support

SHMP efficacy in reducing tartar accumulation

Three studies have been conducted using Eukanuba® adult foods to test the effectiveness of the SHMP technology in reducing tartar accumulation.5 The studies were of a crossover design and were conducted using the Veterinary Oral Health Council (VOHC) protocol.6 All studies were conducted on adult dogs with normal dentition. In each study, dogs were stratified into two groups with foods randomly assigned to each group.

All dogs received a dental cleaning at the start of the study and were then assigned to a control diet group or a group fed a diet with an SHMP coating. At the end of 28 days, the dogs were evaluated for tartar, their teeth were cleaned, and they were switched to the opposite diet. At the end of the second 28 days, the dogs were evaluated for tartar accumulation again.

Meta-analysis of the clinical studies shows that the food coated with SHMP significantly reduced the rate of tartar buildup by up to 80% in 28 days (p < 0.05) when compared with a food that did not have a coating of SHMP. Average reduction in tartar accumulation was 47%.7

Tartar Accumulation (click to enlarge)

SHMP-coated kibble vs. high-fiber, abrasive technology

Thirty-three senior dogs, ranging in age from 6 to 11 years old and representing multiple breeds, were included in a double-blind, crossover study, consisting of three 35-day periods.8 The study followed VOHC protocol.

Dogs were randomly assigned to one of three dietary treatment groups: control food; control food coated with SHMP; and high-fiber, abrasive dental food. Before being assigned to a group, the dogs received a dental cleaning. At the conclusion of each feeding period, the dogs were returned to the clinic for tartar evaluation and a cleaning, until all dogs were evaluated with each of the three diets.

The results of this study demonstrated that dogs fed the diet coated with SHMP had significantly less tartar buildup (37%; p < 0.05) than did dogs fed the high-fiber, abrasive diet. In addition, the diet with a coating of SHMP significantly reduced the rate of tartar accumulation by 51% on the canine teeth and 46% on the premolar teeth, versus the high-fiber, abrasive food (p < 0.05). These findings point to the effectiveness of a coating of SHMP on food on chewing and non-chewing teeth.

Conclusion

The high occurrence of dental health problems in the general pet population warrants an effort to increase awareness and develop effective dental care strategies. Optimal pet oral care requires a partnership between the veterinarian and the pet owner. Dentistry should be incorporated into the overall preventive health care program starting with the puppy or kitten. Clients play an important role in performing daily activities that promote oral health, including daily plaque and tartar control and dietary choices. Nutrition can provide dental benefits as shown in canine studies with SHMP-coated kibble. In some homes, feeding a pet food with proven oral health benefits may be the only step taken to reduce the accumulation of plaque and tartar.

"Did you know...?" (click to enlarge)

REFERENCES

1. Data on file. Client dental survey. Trone Inc., Jan 2011.

2. Banfield Pet Hospital® State of Pet Health 2012 Report. Available at: http://www.stateofpethealth.com/.

3. Glickman LT, et al. Association between chronic azotemic kidney disease and the severity of periodontal disease in dogs. Prevent Vet Med 2011; doi:10.1016/j.prevetmed.2011.01.011.

4. Bellows JE. Spotlight on research: Prevalence of retroviruses in feline oral disease cases. Viewpoint. IDEXX Laboratories, 2006.

5. Johnson RB, et al. Dietary technology for inhibition of calculus formation in companion animals. Recent Advances in Dental Health Management. Presented at 8th World Veterinary Dental Congress. The Iams Company: Dayton, Ohio, 2003;23-25.

6. Veterinary Oral Health Council. Protocols and submissions. Available at: vohc.org/protocol.htm.

7. Data on file. P&G Pet Care, 2012.

8. Lepine AJ, et al. Clinical investigation of dental diet efficacy in the senior dog. Recent Advances in Dental Health Management. Presented at 8th World Veterinary Dental Congress. The Iams Company: Dayton, Ohio, 2003;26-32.