The consequences of poor dental health go way beyond bad breath.
The consequences of poor dental health go way beyond bad breath. Periodontal infection is linked to serious health concerns ranging from tooth loss to bacterial infection of the heart, liver, and kidneys.1 It's also no secret that dental problems are common in animals, with periodontal disease at or near the top of the list of the most commonly diagnosed diseases in adult dogs and cats.2 When our animal patients receive good dental care, they undoubtedly live longer and better lives.
Daniel T. Carmichael, DVM, DAVDC
The specific dental problem we strive to prevent is periodontal disease, which is related to the presence of plaque bacteria on the tooth surface. The goal of dental home care is to remove plaque to retard calculus accumulation on the tooth surface. Plaque bacteria can colonize a clean tooth in 24 to 36 hours. So within a few days of a professional dental cleaning, a pet's teeth are already accumulating the bacteria that will again cause periodontal inflammation and disease. The good news is that home care can prevent this accumulation.
Unfortunately, what is best for our patients isn't always what gets done. Unscientific polls of veterinarians attending continuing -education lectures confirm that many pets, even those owned by veterinarians, go without dental home care. In some cases, the reason is the pet itself (e.g. the pet bites or runs away). But in many cases, it simply boils down to a lack of adequate client education or a lack of motivation on the pet owner's part. As veterinarians, our job is not only to educate our clients about the available products to perform home care, but more important, to motivate clients by underscoring the serious nature of the disease we are trying to prevent.
Dental home care for veterinary patients starts at the veterinary office. Patients must be evaluated for dental disease and treated, if necessary, before a home care program is begun. Eighty percent of dogs over the age of 3 and at least 50% of cats have advanced periodontal disease that requires immediate professional treatment.2 Professional dental treatment, performed when needed and while a pet is anesthetized, is the cornerstone of preventive dental health for our patients. On average, dogs and cats benefit from an annual prophylaxis starting at the age of 3, but each patient needs an individualized dental program.
As part of your canine patients' dental programs, consider incorporating a recently developed bacterin to prevent periodontitis (alveolar bone loss). The bacterin (Porphyro monas Denticanis-Gulae-Salivosa Bacterin—Pfizer Animal Health) is conditionally licensed for vaccinating healthy dogs to help prevent periodontitis associated with Porphyromas gulae, Porphyromas salivosa, and Porphyromonas denticanis—the three most common black-pigmented anaerobic bacteria isolated from dogs with periodontitis.3 A reasonable expectation of this bacterin's efficacy has been shown in experimental studies.4 A clinical trial is currently under way that evaluates the safety and efficacy of the bacterin in client-owned dogs. However, study results are not yet available. This bacterin, in addition to annual prophylaxis and daily home care, is yet another means of preventing periodontal disease.
Dental home care is contraindicated in pets with painful dental problems, including feline odontoclastic resorptive lesions and fractured teeth with exposed pulp. In fact, the discomfort caused by trying to brush a painful tooth may adversely condition the pet to fear future attempts at home care. So home care, especially feeding a textured dental diet, should be instituted only after appropriate professional treatment has established a clean and healthy mouth (except in the youngest and healthiest of patients).5 Ideally, dental home care programs should be started in puppies and kittens before any dental pathology has started.
The Veterinary Oral Health Council (VOHC) provides an objective means of recognizing products that meet standards of effectiveness in controlling the accumulation of dental plaque and calculus in dogs and cats. The VOHC does not test products itself. Companies wishing to have a product reviewed submit a detailed report of the testing that has been performed using VOHC protocols and standards. If, after detailed review of the submission, the VOHC agrees that the product meets its standards, the product is awarded the VOHC seal. More information on the VOHC and the products that have earned the VOHC seal can be found at www.vohc.org.
Daily tooth brushing is the best thing you can recommend for pet owners to do at home to promote good oral hygiene.6 Brushing a pet's teeth once a week, or even every three days, is not enough. Daily tooth brushing is necessary because plaque bacteria can recolonize the tooth surface in 24 to 36 hours. Besides reducing the risk of periodontal disease, owners who brush their pets' teeth on a daily basis are more likely to identify other oral pathology (e.g. fractured teeth, dental resorptive lesions, oral tumors) that would go unnoticed without daily inspection of the oral cavity.
Begin by teaching owners how to brush their pets' teeth (see the client handout). The toothbrush should be soft-bristled; in my experience, a battery-powered toothbrush (Hartz) for dogs performs well, and most dogs don't object to the vibrations. Another appropriate choice is a soft-bristled children's toothbrush. The traditional long-handled and double-ended pet toothbrush can be cumbersome for small breeds but is appropriate for large and dolichocephalic breeds. Although any method of mechanical plaque removal is better than nothing, finger brushes have an ineffective design and are less beneficial than traditional toothbrushes.
Toothpaste is simply a flavoring to enhance acceptance of the toothbrush. Studies in people show that the use of dentifrice does not contribute to the instant mechanical plaque removal during manual tooth brushing.7 The mechanical action provided by the use of a toothbrush is the main factor in the plaque-removing process. There have been various claims of benefit from enzyme systems in some veterinary toothpastes, but research has yet to validate these claims. Always discourage the use of human toothpaste in pets because it contains fluoride, which should not be swallowed.
Several commercial diets have been shown to better promote periodontal health compared with regular dry food diets. Studies document a significant reduction in the plaque, calculus, and gingivitis index for the foods tested.8 The mechanism of action for these dental foods is based on either enhanced textural characteristics of the kibble to mechanically cleanse the teeth (e.g. Prescription Diet t/d—Hill's; Science Diet Oral Care—Hill's; Purina Veterinary Diets DH—Nestlé Purina; and Friskies Feline Dental Diet—Friskies Petcare) or chemical coating of the food with polyphosphate (e.g. Iams Dental Defense—Iams and Eukanuba Adult Maintenance Diet for Dogs—Iams). The polyphosphate coating binds and chelates minerals in the saliva to make them unavailable for calculus development. Therefore, the diets that use enhanced textural characteristics can reduce plaque as well as calculus, whereas the chemical-coated diets are effective only against calculus. One dental diet, Dental DD (Royal Canin), combines the mechanical and chemical properties of textural enhancement with polyphosphate coating. With the high incidence of periodontal disease in dogs and cats, a diet that promotes good oral health is an excellent choice in most pets.
Chew treats such as rawhide can also help remove plaque and tartar from a dog's teeth.9-11 Rawhide hasn't been observed to cause digestive problems in the studies documenting its efficacy in plaque and tartar control. However, swallowing larger pieces of rawhide could cause gastrointestinal tract problems (e.g. esophageal foreign body). Advise owners to provide size-appropriate rawhides that cannot be swallowed as a whole; smaller pieces of rawhide should be discarded. Plaque and tartar reduction is enhanced in rawhide treats coated with calcium-sequestering substances such as sodium hexametaphosphate.12 Chew treats that have earned the VOHC seal of approval include Tartar Check Dog Biscuit: Small and Large Sizes (Del Monte Pet Products), Friskies Cheweez Beefhide Treats (Friskies Petcare), Hartz Dental Flavor Infused Chews (Hartz), Vetradent Dog Chews (Vetradent), and Feline Greenies (S&M NuTec).
Some chew toy products are not recommended because of their tendency to cause tooth fracture (Figure 1). Products such as nylon bones, cow hooves, and real bones are too hard and often are associated with slab fractures of the carnassial teeth in dogs. In addition, tennis balls cause abrasion (mechanical wearing of the tooth surface), so they are not recommended.
Figure: 1. Some chew toys should be avoided. This slab fracture of the maxillary fourth premolar (carnassial tooth) was caused by chewing on a nylon bone.
A more recent option for helping prevent periodontitis is applying OraVet (Merial), which is a biologically inert polymer that bonds to a tooth's surface to help reduce plaque and calculus formation. The product is easy to apply on anesthetized patients after dental prophylaxis and must also be applied weekly at home to maintain the protective barrier. OraVet must not be placed below the gum line (i.e. in the root surface in periodontal pockets) as it will prevent gingival connective tissue reattachment. Thus, it may be counterproductive if placed below the gum line after root planing and gingival curettage. A study has documented the effectiveness of OraVet in plaque and calculus prevention.13 OraVet should be thought of as another tool in the home care armamentarium that can be used in conjunction with tooth brushing and other home care techniques to promote periodontal health.
Oral disinfectants such as chlorhexidine gluconate and chlorhexidine digluconate are another home care option for clients. After binding to gingival tissue, chlorhexidine kills bacteria that can cause periodontal disease and halitosis for up to 48 hours; bacterial resistance does not develop. Chlorhexidine can cause staining of the tooth surface that is reversible. Chlorhexidine is recommended in cases of chronic periodontitis; instruct owners to use chlorhexidine at least twice a week (or even daily) in addition to regular tooth brushing. Healthy gums are more important than reversibly stained teeth.
Maxi/Guard (Addison Biological Laboratory) is an oral gel that contains zinc ascorbate. Zinc is antibacterial, and ascorbic acid (vitamin C) is necessary for collagen production. A study in cats showed a significant decrease in plaque, gingivitis, and anaerobic periodontal pathogens in the group treated with zinc ascorbate gel.14
Other oral rinse products containing chlorine dioxide work well for combating halitosis by neutralizing malodorous sulfur compounds. But keep in mind that simply covering up odor will not help any underlying pathology.
Many pet owners still do not know the importance of good oral health for their animal companions. It is our responsibility as veterinarians to educate clients about why it is important to maintain good oral health as well as how to do it. Many veterinarians will delegate this important task to a trained veterinary technician, and this is a perfect role for the veterinary dental technician to excel in. An ideal time to discuss home care techniques is at the time of discharge after a professional cleaning or, better yet, at a two-week recheck appointment when any extractions or other procedures have healed. Client education must be incorporated into the complete oral heath assessment and treatment plan.
Editors' Note: Dr. Carmichael has consulted for Merial, Hartz, Henry Schein, Webster, and Pfizer and has been sponsored by the above companies to provide education lectures.
The information and photographs for "Dental Corner" were provided by Daniel T. Carmichael, DVM, DAVDC, Veterinary Medical Center, 75 Sunrise Highway, West Islip, NY 11795.
1. DeBowes LJ, Mosier D, Logan E, et al. Association of periodontal disease and histologic lesions in multiple organs from 45 dogs. J Vet Dent 1996;13:57-60.
2. Wiggs RB, Lobprise HB. Periodontology. In: Veterinary dentistry. Principles and practice. Philadelphia, Pa: Lippincott-Raven, 1997:186-231.
3. Hardham J, Dreier K, Wong J, et al. Pigmented-anaerobic bacteria associated with canine periodontitis. Vet Microbiol 2005;106:119-128.
4. Product insert: Porphyromonas Denticanis-Gulae-Salivosa Bacterin, Pfizer Animal Health, Exton, Pa.
5. Hale F. Home care for the dental patient. Hill's European Symposium on Oral Care. Amsterdam, 2003;50-59.
6. Gorrel C, Rawlings JM. The role of tooth-brushing and diet in the maintenance of periodontal health in dogs. J Vet Dent 1996;13:139-143.
7. Paraskevas S, Timmerman MF, van der Velden U, et al. Additional effect of dentifrices on the instant efficacy of toothbrushing. J Periodontol 2006;77:1522-1527.
8. Veterinary Oral Health Council (VOHC) www.vohc.org. Harvey CE. Director. Data on file.
9. Hennet P. Effectiveness of an enzymatic rawhide dental chew to reduce plaque in beagle dogs. J Vet Dent 2001;18:61-64.
10. Gorrel C, Bierer TL. Long-term effects of a dental hygiene chew on the periodontal health of dogs. J Vet Dent 1999;16:109-113.
11. Lage A, Lausen N, Tracy R, et al. Effect of chewing rawhide and cereal biscuit on removal of dental calculus in dogs. J Am Vet Med Assoc 1990;197:213-219.
12. Stookey GK, Warrick JM, Miller LL, et al. Hexametaphosphate-coated snack biscuits significantly reduce calculus formation in dogs. J Vet Dent 1996;13:27-30.
13. Gengler WR, Kunkle BN, Romano D, et al. Evaluation of a barrier dental sealant in dogs. J Vet Dent 2005;22:157-159.
14. Clarke DE. Clinical and microbiological effects of oral zinc ascorbate gel in cats. J Vet Dent 2001;18:177-183.