Improving veterinary dentistry: The purpose of the Veterinary Oral Health Council and veterinary specialists (Sponsored by Greenies)


Recently, a group of veterinary dental specialists, most of them members of the Veterinary Oral Health Council (VOHC), came together to discuss the role of the VOHC for both the veterinarian and the consumer.

Recently, a group of veterinary dental specialists, most of them members of the Veterinary Oral Health Council® (VOHC), came together to discuss the role of the VOHC for both the veterinarian and the consumer. The VOHC's stated purpose is to "recognize products that meet preset standards of plaque and calculus (tartar) retardation in dogs and cats. Products are awarded the VOHC Seal of Acceptance after a review of data from trials conducted according to VOHC protocols." The VOHC seal is the pet product equivalent to the Amercian Dental Association (ADA) seal. The VOHC strives to maintain the highest credibility among the veterinary community and to help prevent the most common dental disease in dogs and cats — periodontal disease. To further this effort, these specialists were given the opportunity to discuss their views on various types of dental products offered by the pet industry today as well as on areas for improvement in both dental product selection and veterinary dentistry as a whole.

The VOHC's objective

Dr. Bradley Quest (Moderator): Welcome, and thank you for participating in this roundtable discussion. Many practicing veterinarians are unaware of the function of the Veterinary Oral Health Council and what its seal of acceptance means to them. What is the purpose oftheVOHC?

Bradley Quest, DVM, Product Development Veterinarian for the GREENIES® brand and The Nutro Company.

Dr. Colin Harvey: The VOHC started in the mid-1980s when a company marketing treats approached the American Veterinary Dental Society (AVDS) and requested its endorsement. The AVDS board of directors decided they did not have the information needed to make an endorsement. After that, there were several informal meetings of industry representatives and the veterinary dental community. It became clear that having a formal way to recognize effective products was necessary, and companies with products for which research had been conducted proving their effectiveness wanted a way to differentiate their product from the rest of the noise in the marketplace. That is where the VOHC comes in. It is an attempt to provide an independent method using a preset standard as a way of ensuring that veterinarians and the public can find out which of those products have reached that high standard. The council consists of nine members, and the current members are all diplomates of the American Veterinary Dental College (AVDC). Council members are selected by the board of the AVDC, based on their interest in oral hygiene, and specifically veterinarians who have a background in product testing or in the science of evaluating techniques or other areas within veterinary dentistry. They must be willing to be clear that a claim either is or is not supported by the data. Typically, council members serve for five to six years.

Colin Harvey, BVSC, FRCVS, DACVS, DAVDC, Director of the Veterinary Oral Health Council (VOHC) and Professor of Surgery and Dentistry at the University of Pennsylvania.

Dr. Quest: What does a VOHC seal on a product mean?

Dr. Laura LeVan: The seal means that the company has submitted its science to the independent council of VOHC, and the VOHC has determined that the product meets the claims. As a veterinarian, I can then pass this knowledge on to the public and fellow veterinarians.

Laura LeVan, DVM, DAVDC, Owner of Veterinary Dental Education Center, Concord, Mass., and VOHC member.

Dr. James Anthony: The whole idea is to compare apples with apples and not apples with oranges. The point is to reduce confusion so that owners can evaluate whether a particular product is appropriate for their pet. The standards are strict, but VOHC helps companies address issues so that their products can meet the standards. Companies obviously want to have a level playing field, where all products are evaluated using the same set of criteria.

James Anthony, DVM, MRCVS, DAVDC, DEVDC, Associate Professor and Head of Dentistry and Oral Surgery at the University of Saskatchewan Western College of Veterinary Medicine, and VOHC member.

Dr. Quest: Why wouldn't all companies with dental products want to carry the VOHC seal on their products?

Dr. Harvey: There are some obvious gaps in the VOHC list. For products that are used infrequently or in less volume, like dentifrices, gels, or toothbrushes, it may be hard to justify the cost of testing to demonstrate that the VOHC standard has been met. The VOHC would love to list that kind of product to enlarge the range of products that carry the seal. The VOHC and the AVDC consider teeth brushing a gold standard of dental care, but there is no brush or dentifrice on the accepted list at this time. A gel for dogs and cats is now on the list, as is a water additive product, which represents a big step. Another reason why some companies may not pursue approval is that the VOHC system has a preset standard, and the consumer sees the same seal whether a product meets that standard by just a little bit or exceeds the standard greatly.

Dr. Quest: Do the veterinary colleges educate students to recommend mainly products that carry a VOHC seal?

Dr. Anthony: Those of us in academic institutions have to be open-minded and aware of everything, but we should always base decisions on solid research. Just because a product doesn't have the VOHC seal doesn't necessarily mean it is bad. What the seal does say is that this product has met certain criteria that we know means that it is effective. The VOHC reviews the research critically and makes sure the criteria are met.

The VOHC seal: Standards and testing

Dr. Quest: What is the testing methodology for products seeking the VOHC seal?

Dr. Harvey: The testing methodology is based on proving that there is a retardation of plaque and calculus accumulation — plaque causes periodontal disease, and calculus (tartar) exacerbates or enhances plaque accumulation. The FDA is the regulatory agency for veterinary products, and a representative was involved in the discussions that led to the development of the VOHC. We were encouraged by the FDA to come up with a system that helps consumers understand product claims for dental products that reduce plaque and calculus (tartar) accumulation. The VOHC web site lists protocols to prove that a product is effective. We require a clean tooth model so that the plaque or calculus (tartar) is easy to measure on teeth that have been scaled. We also require companies to measure the rate of accumulation of plaque and calculus, and the required control group must be fed dry food so that it is not an easy standard to exceed. The data are submitted and then reviewed by an independent statistician to ensure that the correct and appropriate analysis was done. Then the council will forward the recommendation to the AVDC board of directors, which is the final arbiter of what goes on the VOHC-accepted list.

When VOHC was founded, we based the standards on the American Dental Association model. At that time, the ADA seal was given for fluoride toothpastes that were effective in preventing caries. Since then the ADA has enlarged its seal system to include consideration of plaque retardation and suppression of gingivitis, adopting a 15°/o/2O°/o standard, meaning 15% in any one trial and 20% as the mean of the two required trials is the minimum required difference from the control group. Some pet products display "up to XX%" plaque reduction in advertisements, based on the top percentile of testing data. These upper percentile scores are not reviewed by VOHC when a submission is considered and are not endorsed as useful information by VOHC because VOHC concerns itself with overall efficacy, as demonstrated by the mean percent retardation of plaque and/or tartar. The VOHC has since also adopted the ADA standard. Even though both the AVDC and the VOHC recommend brushing, unfortunately there is currently no toothbrush on the list of VOHC-accepted products. The VOHC recently released information on protocols for studies of products such as toothbrushes or the equivalent. We are using the ADA safety specifications for brushes. When a human brush is used in a veterinary patient, we have to be aware that there might be problems because of the shape or size relative to the size of the patient's mouth.

Dr. Quest: Does the VOHC itself evaluate the products for safety, and what concerns should people have about products that don't carry the seal?

Dr. Harvey: The FDA is the regulatory agency, so concerns about safety are directed to the FDA. There has been concern about the safety of some products, particularly food and treats. So the VOHC now incorporates some specific safety requirements. Also, when a product receives the VOHC seal, the company signs an agreement that it will report any problems with the product so that the VOHC can pull the company using the seal on that product if there is a safety concern.

Dr. Jan Bellows: Another concern is that just because an ingredient in a product has been shown effective, it doesn't mean the product is effective. For example, if there is a drop of chlorhexidine in a product, it has chlorhexidine, but will it be effective? Spraying or washing an animal's mouth with chlorhexidine once a day would not be effective. The animal would have to gargle or chew a chlorhexidine-laden product for an extended period because chlorhexidine requires at least a minute of contact time with the tooth surface to be effective.

Jan Bellows, DVM, DAVDC, DABVP, Owner of All Pets Dental in Weston, Fla., and incoming President of the American Veterinary Dental College.

Dr. Harvey: Chlorhexidine is an interesting example because it is readily bound and therefore may be unavailable. There was a company that was marketing chlorhexidine in a shrimp flavor and a chocolate flavor in Europe. There was no evidence that the product was effective. Understanding the science of how these things work is where the VOHC comes in. Chlorhexidine will be readily diluted unless it is held in contact with the teeth. That's one of the advantages of the gel product.

Dr. Anthony: I have concerns with natural products, especially those of plant-based origin. So much of the active component of the plant that produces the beneficial effect can vary, depending on variables such as when the plant was harvested and whether it was a good or poor moisture year. There is no quality control of the active ingredient.

Dr. Harvey: Yet, it is important to be open to unexpected possibilities. There are products that are being marketed now that include ingredients such as seaweed or grapefruit seeds. Who knew that these things might be effective? Whether there is evidence to show that they are effective is what is critical. There are agents that are effective chemically both as anti-plaque and anti-calculus (anti-tartar) agents. If a chemical is included on an FDA-regulated GRAS (generally recognized as safe) list of chemicals that are accepted for inclusion in foodstuffs for animals and people, then the VOHC accepts use of those chemicals in the product. The VOHC still requires safety testing of these products, which involves gingivitis scoring at the beginning and at the end of the test period.

Resources for learning more about veterinary dentistry

Treats and chew toys

Dr. Quest: What types of qualities do you look for in a treat or chew toy when you are going to recommend it?

Dr. Bellows: I caution owners of dogs and cats about the hardness. Many people offer their dogs bones. Bones aren't safe, because they don't bend and are harder than the tooth itself. Neither are cow hoofs, nylon products, and ice cubes. The maxillary fourth pre-molar or canine tooth is mostly at risk for fracture when hard products are chewed. The tooth is going to break. I tell people that whatever they give has to bend. You also have to consider whether a dog is a chewer or a gulper. Some dogs will have rawhide get caught down the esophagus. Rawhide doesn't dissolve in the esophagus, so it can be a big safety concern.

Dr. LeVan: I agree with that. I also tell owners to watch their pet when they give it a treat. As they would supervise their children, they should watch their pet to see what it does with the toy or treat, and remove it if necessary. I appreciate that the VOHC considers safety so I can trust that my professional organization is helping me pass on accurate information.

Dr. Harvey: Dogs will spend a lot of time trying to get something out of the bone, and all it does is put excessive stress on their teeth and of course they fracture. There are owners who can feed raw meaty bones, which are softer, and don't have any problems as a result, but these dogs generally are fed in the yard rather than on the kitchen floor or living room carpet.

Dr. Anthony: Some dogs are ferocious chewers and will crunch down on everything to get that little bit of marrow inside. That will cause problems, especially with their carnassial teeth. Others are very picky chewers, and bones wouldn't be a problem. Also, raw bones may carry a serious bacterial burden.

Dr. Harvey: One of the most sensible ways to use rawhide is to give it to the dog to chew on for 20 minutes and then put it back on the shelf. The next day, give it to the dog for another 20 minutes. The dog will think it is a new toy. This also gives owners a chance to inspect the rawhide between chewing sessions and trim off loose ends or discard the product. There is a dental benefit, and the frequency of the chewing is really the key with oral hygiene. If it is not done every day, it is not nearly as effective.

Dr. LeVan: If you get one of these gulpers you should not give them products designed to be chewed. I always recommend brushing. There are also some gel products and water additives that can be used.

Dr. Quest: Should companies do digestibility or solubility testing on products to show that if a dog does swallow a large piece that it will dissolve?

Dr. Bellows: Yes. If a product will completely dissolve and is made out of natural ingredients, that is best because clients look at labels.

Dr. Anthony: VOHC hasn't looked at chew toys yet. There are more than 2,000 different types of these products in North America, and some make huge claims about preventing periodontal disease and plaque and calculus accumulation, but there is virtually no research. With chew toys, the owner needs to know the dog or cat and how that pet chews. If the pet rips things apart, it will break off chunks of an inedible product, and you are just asking for a foreign body impaction. There is a benefit in the mechanisms of chewing on something — some calculus or plaque removal from the mechanical action, some flushing of the gingival sulcus with fluids. So these products can help.

Dr. Bellows: I was taught that the only way to remove plaque and calculus was through mechanical means. Things are changing. Still, we don't want pet owners being overconfident that their pets are not going to get gingivitis and periodontal disease because they're using VOHC-accepted products. Adding a product to the water may decrease plaque and tartar, but unless some sort of mechanical removal is instituted, plaque, calculus, and gingivitis will occur in time. I do recommend Kong toys. Some dogs just have to chew, so it's better to have them chew something that is considered safe.

Dr. Harvey: There are some treats that are unbelievably palatable, such as GREENES® dental chews and treats, that make it fun for the owner to give to the pet.

Dr. LeVan: I also recommend Kongs, but if a dog is obsessive about a toy, no matter what it is, it's going to be a problem. I treated a police dog that had to have a Kong in her mouth all day long to prevent her from "eating" the cruiser. She abraded the back of her canine teeth, and I had to protect them with cast metal crowns to minimize the wear; however, after five years, she abraded the stainless steel on the crowns. I often tell that story to clients because any toy, even a good one, can be a problem for a particular pet.

Dr. Anthony: What it comes down to is choosing the right products for patients that will also be easy for owners to use. That customization process is where veterinarians can be a big help to consumers. We should be aware of what types of products would benefit a particular pet. There are many ways of attacking plaque and calculus, and I think all avenues should be explored. We should be open to the development of new products that will help retard plaque and calculus.

Periodontal disease and systemic health

Dr. Quest: What's the impact of periodontal disease on systemic health?

Dr. Harvey: There is no way of knowing if a dog is going to live a shorter period if it has terrible periodontal disease. Some correlations between periodontal disease and heart, liver, and kidney disease have been shown. There is also more recent evidence showing a relationship between periodontal disease and the body-wide measure of acute stress or inflammation, C-reactive protein. This study was published in a recent issue of the Journal of the American Veterinary Medical Association. 1 It showed that when you treat periodontal disease in dogs, the C-reactive protein concentration is reduced.

Dr. Bellows: It is inarguable that periodontal disease, especially advanced disease, causes pain. Generally after evaluation and receiving care, the dog or cat returns to eating or to grooming itself. Clients certainly don't want their pets to be in pain, and periodontal disease causes pain. Advice on preventing plaque and calculus is one of the finest gifts a veterinarian can give to patients and clients.

Dr. Harvey: The criteria for measuring the impact of oral pain on an animal are very difficult to pin down. But we've all seen the 10-year-old cocker spaniel that following a combination of extractions and scaling because of severe periodontal disease acts like it is a 1-year-old again.

Dr. Bellows: When an animal comes in with periodontal disease and the bacteria in its mouth have changed from gram-positive to mostly gram-negative bacteria, you can smell it as soon as you walk into the exam room. I ask the owners how they live with the dog. They say, "It doesn't really smell that bad." Once care is given and the affected teeth are extracted, the halitosis generally resolves; then the owner notices the difference.

Dr. Anthony: The extension of oral bacteria into the respiratory tract resulting in tracheitis, bronchitis, even pneumonia should get more consideration. There have been some studies in human medicine, but there still needs to be a lot more research done in this area.

Improving the field of veterinary dentistry

Dr. Anthony: Recently, there has been more emphasis placed on veterinary dentistry as more research is being published, and private practitioners and the public are becoming more aware of dental disease. A lot of colleges in Canada now promote dentistry programs in their curriculum. We are starting to see some of the benefits of this in western Canada. People are more aware, and practices are doing more.

Dr. Harvey: There are more schools that have dental programs staffed by diplomates, and there are others that have someone who is not a diplomate but who is in training or provides dental service for the hospital and for the educational program.

Dr. Bellows: In many schools, the dental courses are electives, and only so many students can take them. It would be nice to have hands-on wet labs so the students can use a high-speed handpiece, take dental x-rays, and sit down with somebody who knows about dentistry and the value of dentistry to the practice of companion-animal medicine and surgery.

Dr. Harvey: At the past couple of annual meetings of the student AVMA, they have had dental wet labs, which have been hugely popular and were sponsored by instrument manufacturers and equipment companies. There is a possibility for extending that considerably.

Dr. Quest: What aspects of oral care need more emphasis?

Dr. LeVan: General practitioners need information. The day after graduation, they may perform dental procedures. But they don't necessarily have the knowledge they need. Photographs of normal and pathologic conditions in the oral cavity are popular sections in my lectures to veterinary professionals.

Dr. Anthony: Veterinarians need further education to identify oral pathology and to understand the pathophysiology of disease. A lot of things are overlooked. Only with that understanding can you plan treatment.

Dr. Bellows: Some practitioners will catch the passion and become thirsty for dental education. There is such a wealth of information that general practitioners can get to better recognize oral pathology before deciding what to do next.

How can the VOHC advance veterinary dentistry?

Dr. Quest: Let's elaborate a little bit more on some of the work the VOHC does.

Dr. Harvey: The VOHC has always taken a very narrow view of its purpose, which is to be a credible recognition system. Therefore, it avoids doing anything that would lead one to question this credibility. Others need to take that credibility and make use of it.

Dr. Bellows: On the human side, when the public wants good information about dentistry, they know to go to the ADA's web site, and the companies that have the ADA seal benefit from that. It would be ideal for the VOHC to become the public clearinghouse of quality dental education.

Dr. Harvey: The VOHC web site is practical, but, in its current form, certainly not particularly professional, attractive, or designed to provide that next level of information. The AVDC is in the process of enlarging its public information pages on its web site. There is no reason why the VOHC couldn't do that too. If the web site is enhanced so that it is the equivalent of the ADA site, it would go a long way toward encouraging veterinarians to use the VOHC site.

Dr. Anthony: Exposing the public to the VOHC would be beneficial. Companies have invested a lot of capital into VOHC testing and have made a commitment to the superiority for their products. Consumers need to be made aware of that.

Dr. LeVan: The VOHC needs more outreach to veterinary professionals. Veterinarians don't know enough about the VOHC. If we educate general practitioners, they could be VOHC advocates too, which, in turn, would educate pet owners.

Dr. Quest: It would be good to get exposure at the major veterinary conferences to build awareness.

Dr. Harvey: One of the companies has, in fact, suggested a VOHC booth. Not to provide samples, but to point attendees to the booths for the VOHC-participating companies, and so that veterinarians could get a sense of how those products earned the VOHC seal.

Developing your interest in veterinary dentistry

Dr. Bellows: Most veterinarians probably do not know which products are VOHC approved. We need to scrutinize a little more closely the ADA model and see how they continue to operate with credibility and are able to increase awareness.

Dr. Anthony: The importance of combining the use of products instead of using just one product should be emphasized by the VOHC. People may have tried these products and because one wasn't 100% effective they are disillusioned.

The VOHC around the world

Dr. Quest: There have been some data that show that the awareness of VOHC in the United States is rising. Is the VOHC also recognized in other countries?

Dr. Harvey: Yes. The VOHC is recognized by the Australian Veterinary Dental Society, the European Veterinary Dental Society, and the British Veterinary Dental Association. We have a written agreement with the non-North American organizations that they will not establish their own effectiveness recognition system. We want to avoid multiple standards, so that the same product that is marketed in North America and in Australia can carry the same seal. There is also an informal agreement with the Japanese Veterinary Dental Association.

Dr. Quest: Is there input from the international organizations to the VOHC, and is membership open to people from these other organizations as well?

Dr. Harvey: We have had council members who are based in Europe. We want people who are going to be able to do the job in an informed and interested way. As additional countries develop their own system, the VOHC will reach out to let them know that they can sign on. They can have the European Veterinary Dental Society seal as well as the VOHC seal on a product, for example.

Dr. Quest: I'd like to thank everyone for participating in this discussion on the role of the VOHC in veterinary dentistry. We had an insightful discussion regarding the value of dental products that carry the VOHC seal, and how veterinarians can approach product recommendations to improve the dental health of their patients.


1. Rawlinson JE, Goldstein RE, Reiter AM, et al. Association of periodontal disease with systemic health indices in dogs and the systemic response to treatment of periodontal disease. J Am Vet Med Assoc 2011;238(5):601-609.

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