Do Dental Chews Actually Clean Dog Teeth

More than 80 percent of dogs over age 3 already have periodontal disease. In Swedish surveys, fewer than 4 percent of owners brush daily. The chew industry has stepped into that gap with a marketing claim that's roughly half-true, a regulatory seal with a lower bar than most people assume, and a documented body count from the early 2000s most articles skip.

Periodontal disease affects more than 80 percent of dogs over age 3, and fewer than 4 percent of owners in Swedish surveys brush their dogs' teeth daily. Type "do dental chews actually clean dog teeth" into a search bar and you'll mostly get listicles ranking 10 brands. Type the same question into a peer-reviewed database and the answer gets sharper and less flattering. Yes, the right ones do something. Only the ones with a specific seal on the package. And not nearly as much as the bag suggests.

The Veterinary Oral Health Council awards its Seal of Acceptance to chews that meet a minimum bar in two clinical trials: a 15 percent reduction in plaque or tartar in each trial, with a 20 percent mean across both. That's the floor. A peer-reviewed comparison published in the Journal of Small Animal Practice in 2019 found daily tooth brushing was more than three times as effective at controlling plaque accumulation as a daily dental chew or a prescription dental diet. The chews work. They just don't work as well as the brand on the bag suggests.

The VOHC seal sounds like a guarantee. It's a floor.

The Veterinary Oral Health Council was founded in 1997 to bring some scientific discipline to a category full of marketing claims. The seal on the bag means a manufacturer ran two trials and showed at least a 15 percent reduction in plaque or tartar in each, with a 20 percent average across both, against a control group, with statistical significance. That standard was set in January 2011 to align with the American Dental Association's threshold.

Two facts about how the seal works are worth understanding before paying $30 a month for chews. First, VOHC does not run the trials. Manufacturers do, then submit the data for review. Second, VOHC declined to require digestibility or mechanical safety testing as part of its accepted-list review. The manufacturer attests to safety; VOHC certifies efficacy. From the council's own news page: it considered whether to require digestibility testing on the accepted list and decided not to, citing variability in the most appropriate tests. The seal certifies that the product reduced plaque or tartar by at least 20 percent on average in trials the manufacturer conducted. It does not certify that any one chew is safe for any one dog to swallow.

A 2011 review article in the Canadian Veterinary Journal by Fraser Hale, while broadly endorsing the VOHC system, made the point plainly: a 10 percent or 20 percent reduction in plaque or tartar alone won't prevent periodontal disease in a predisposed animal, and pet owners shouldn't place too much faith in any product just because it has the seal. The seal is a floor, not a finish line.

The brushing comparison the chew industry doesn't lead with

Allan, Adams, and Johnston ran the cleanest head-to-head trial on this question in 2019. Twenty-two dogs got a routine scale and polish, then were randomly assigned to one of three groups: once-daily tooth brushing with veterinary toothpaste, once-daily dental hygiene chew, or a prescription dental diet. Six weeks later, blinded scorers measured plaque accumulation.

Daily brushing came out more than three times as effective as either the chew or the diet. The chew and diet groups were not statistically different from each other. Both reduced plaque accumulation. Both did so considerably less than brushing did.

The reason this study almost never appears in dental chew marketing is structural: chew brands fund chew research. A trial designed to show their product beats placebo is the trial they'll pay for. A trial designed to compare their product to a toothbrush isn't. Allan et al. exists because the BBC consumer-journalism programme "Trust Me, I'm a Vet" footed the bill, which is roughly the only kind of source likely to commission a comparison no chew company would. The same industry-funding pattern shows up across pet nutrition; our coverage of the FDA's grain-free dog food investigation documents how the same dynamic complicated a regulatory probe into heart disease.

If your dog tolerates brushing and you'll do it daily, you don't need chews for dental health. You may want them as treats. That's a separate conversation from "do they clean teeth."

The FDA case file most articles skip

By early 2006, with CNN reporting that at least 13 dogs had died from complications related to Greenies, the FDA's Center for Veterinary Medicine had confirmed 35 complaints involving 34 dogs and one cat as of March 1, 2006. The reports described the chews failing to break down and lodging in the esophagus or intestine, sometimes requiring emergency surgery, sometimes not in time.

Dr. Brendan McKiernan, a board-certified veterinary internal medicine specialist in Denver, treated nine related cases in two years: six esophageal obstructions and three intestinal. His comment to the trade press at the time, on the manufacturer's claims that the chews were easily digestible: the pieces that obstruct are whole and hard, and it's wrong to suggest otherwise.

Greenies was reformulated in 2006 (by then-manufacturer S&M NuTec, since acquired by Mars Petcare) to be more soluble. In September 2007, US District Judge Gary Fenner approved a class action settlement. The reformulated product carries the VOHC seal in multiple sizes and flavors, and its current label still flags, under an all-caps "ATTENTION:" header, that gulping any item can be harmful or even fatal to a dog. That warning is on the package because the manufacturer learned, by lawsuit, what happens when small dogs gulp large chews. The risk didn't disappear with the reformulation. It got mitigated, then disclosed.

Two takeaways from this history are practical. First: match the chew to your dog's actual weight, every time, and don't size up because the small bag costs more per ounce. Second: supervise. The owners who lost dogs in 2006 weren't negligent. They handed their dog the top-selling pet treat in the country and walked into the kitchen.

What to actually do if you can't or won't brush

The honest hierarchy looks like this. Daily brushing with a dog-safe toothpaste is the gold standard. Every other day works almost as well, per a 2015 study by Harvey et al. tracking four brushing frequencies. Weekly brushing helped racing greyhounds in a 2021 study, but only on calculus, not on gingivitis.

If brushing isn't happening, then VOHC-accepted chews are a real but partial substitute. Look for the seal. The current consumer-facing list includes Greenies, OraVet Dental Hygiene Chews, Purina DentaLife, Whimzees Brushzees, Virbac C.E.T. VeggieDent in several formulations, ProDen PlaqueOff, Milk-Bone Brushing Chews, and Blue Buffalo Dental Chews, among others. Expect to spend $0.50 to $2.50 per chew, or roughly $15 to $75 per month per dog. Anything labeled "dental" without the VOHC seal is making a marketing claim, not a tested one.

Match the chew to the dog's weight, watch the dog eat it the first several times, and stop using that brand if your dog gulps. A chew your dog swallows in pieces is a gastrointestinal obstruction in slow motion, regardless of what the bag says about solubility.

And keep the annual professional cleaning on the calendar. No daily chew, and no daily brushing, replaces a scale-and-polish under anesthesia when the tartar has already calcified. Pet insurance plans increasingly cover routine dental cleanings as preventive care, which makes the annual appointment much easier to keep on the schedule. The chews retard accumulation. They don't reverse it.

So go ahead and buy the Greenies. Just understand what you're buying: a treat that helps a little, with a regulatory floor that's lower than the seal implies, from a category whose worst incidents are documented in court records and FDA files. Then go find the toothbrush.

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Frequently asked questions about dental chews and dog teeth

Do dental chews actually clean dog teeth?

VOHC-accepted chews reduce plaque and tartar by an average of at least 20 percent in manufacturer-funded trials, the threshold set by the Veterinary Oral Health Council in 2011. They work, but they do not work as well as the marketing suggests. A 2019 Allan, Adams, and Johnston trial in the Journal of Small Animal Practice found daily tooth brushing was more than three times as effective at controlling plaque accumulation as a daily dental chew or prescription dental diet. Chews are a real but partial substitute for brushing.

What is the VOHC seal and what does it actually certify?

The Veterinary Oral Health Council, founded in 1997, awards a Seal of Acceptance to chews and dental products that demonstrated at least a 15 percent reduction in plaque or tartar in each of two trials, with a 20 percent mean across both, against a control group with statistical significance. VOHC does not run the trials; manufacturers do, then submit the data for review. VOHC certifies efficacy on those manufacturer trials. It does not require digestibility or mechanical safety testing on the accepted-list review. The manufacturer attests to safety. The seal is a floor, not a guarantee.

Are dental chews safe for dogs?

VOHC certifies efficacy, not safety. The FDA's Center for Veterinary Medicine confirmed 35 complaints involving 34 dogs and one cat related to Greenies as of March 1, 2006, with chews failing to break down and lodging in the esophagus or intestine. Greenies was reformulated in 2006 by then-manufacturer S&M NuTec (since acquired by Mars Petcare) and a class action settlement was approved in September 2007. The current label still flags, under an all-caps "ATTENTION:" header, that gulping any item can be harmful or fatal. Match the chew to your dog's actual weight, supervise consumption, and stop using any brand if your dog gulps.

Is brushing my dog's teeth better than dental chews?

Yes. The 2019 Allan et al. trial randomized 22 dogs to once-daily tooth brushing with veterinary toothpaste, once-daily dental hygiene chew, or a prescription dental diet for six weeks after a routine scale and polish. Blinded scorers measured plaque accumulation. Daily brushing was more than three times as effective as either the chew or the diet, and the chew and diet groups were not statistically different from each other. A 2015 study by Harvey et al. tracking four brushing frequencies found every-other-day brushing works almost as well as daily. Brushing is the gold standard. Chews are the substitute for owners who cannot or will not brush.

Which dental chews are VOHC-approved?

The current VOHC consumer-facing list includes Greenies, OraVet Dental Hygiene Chews, Purina DentaLife, Whimzees Brushzees, Virbac C.E.T. VeggieDent in several formulations, ProDen PlaqueOff, Milk-Bone Brushing Chews, and Blue Buffalo Dental Chews, among others. Expect to spend $0.50 to $2.50 per chew, or roughly $15 to $75 per month per dog. Anything labeled "dental" without the VOHC seal is making a marketing claim, not a tested one. Always match the chew size and formulation to the dog's actual weight, not to the price-per-ounce of the bag.

How does a professional dental cleaning compare to dental chews?

Daily VOHC-accepted chews retard plaque and tartar accumulation. They do not reverse calcified tartar already on the teeth. A scale-and-polish under anesthesia at the veterinarian is the only procedure that removes calcified tartar once it has formed. Annual chews run roughly $180 to $900 per year per dog at $15 to $75 per month. A professional cleaning varies by region, dog size, and oral disease severity, and is increasingly covered by pet insurance plans as preventive care. No daily chew and no daily brushing replaces the annual professional cleaning when tartar has already calcified.