Dental chews - the evidence

RE: Dental chews - the evidence

Sarah Keir — Mon, 09 Nov 2020 19:49:06 GMT

I'm already signed up!

RE: Dental chews - the evidence

Norman Johnston — Mon, 09 Nov 2020 15:53:29 GMT

You can ask the author herself if you register for the webinar tomorrow at Webinarvet

RE: Dental chews - the evidence

Evelyn Barbour-Hill — Tue, 20 Oct 2020 18:08:41 GMT

[quote userid="9515" url="~/001/veterinary-clinical/small-animal/dentistry/f/expert-help/29389/dental-chews---the-evidence/226034#226034"]The practice owner says he practices evidence-based decisions [/quote]

So, umm, why has he decided to sell antlers?

RE: Dental chews - the evidence

Sarah Keir — Mon, 19 Oct 2020 13:11:51 GMT

The practice owner says he practices evidence-based decisions which is why I'm hunting down the evidence to show him but I hadn't considered the full psychological implications of asking him to change.

RE: Dental chews - the evidence

Rachel Perry — Sat, 17 Oct 2020 08:39:15 GMT

Hi Sarah,

This is a an oblique response to your request, but I don't think it matters how many papers you can find (regardless of their quality) supporting your view. The vet in this practice is undergoing cognitive dissonance and he genuinely believes they do no harm. The more evidence you show him, the more psychological distress he'll feel and thus the harder he will look for "evidence" that he is right. All you can do is stand by you know to be true, and offer the best care you can for patients entrusted to you. I agree it's hard when the whole practice is not giving the same advice. He might change if one of his own dogs fractures a tooth and see the consequences ...

I agree that either vets don't notice them or they notice them but dismiss it because "the dog is not bothered by it", only when you convince them to pursue treatment and the dog suddenly becomes like a puppy again can they retrospectively see that it was bothering the dog,. It's a big psychological ask otherwise.

RE: Dental chews - the evidence

Evelyn Barbour-Hill — Fri, 16 Oct 2020 17:43:46 GMT

'Twas I who advocated rawhide chews. Sure, they are too hard when new. But as soon as the dog has got at them a bit, tthey get soggy, and the dog keeps working at the soggy bit. There is also the matter of the size of the thing – it needs to be either a big one (relative to size of dog) or a flimsy one (there is certainly an infinite variety to choose from). Diameter matters – more of this below.

All the risk of fracture on hard objects arises if the dog exerts sufficient muscular force to break the tooth, and not all dogs do that . Especially with rawhide, they start cautiously and work up.

If the object chewed is too hard and the dog exerts maximum muscular force, a carnassial tooth will break – but only if the diameter of the object is such that it can be gripped between the cusps of the carnassial teeth while that force is exerted. If a hard object is too big for that – say, a cow's femur for a Border Collie – it doesn't go between the teeth. The upper carnassial grinds down the side of the bone . If that commonly broke the carnassial, we would commonly see slab fractures on the lingual side. I've not seen many fractures on the lingual side of the upper carnassial, and those I have seen have been fom collisions of various kinds.

The thing to understand about antlers is that not only are they too hard, they offer a range of diameters that are ideal for breaking teeth.

This business is rather like ballistics. The laws of physics are always obeyed. But in any particular case so very many factors become involved that trial and error is eventually needed. Well, antlers have been tried and found guilty. Time they were condemned.

RE: Dental chews - the evidence

Rob Davis — Fri, 16 Oct 2020 17:43:18 GMT

This is and old and slightly obscure paper, but shows dental fractures seen in around 20% of dogs radiographed at the University of Zagreb. The dogs were referred for dental radiography, so it's not representative of the general population. I'm sure there's a better reference out their but I can't find it at the moment... I'll keep looking!

RE: Dental chews - the evidence

Martin Hamilton — Fri, 16 Oct 2020 16:20:19 GMT

There is also the paper by J Soukup in the Journal of Veterinary Dentistry, 2015 titled "Classification and Epidemiology of Traumatic Dentoalveolar Injuries in Dogs and Cats: 959 Injuries in 660 Patient Visits (2004-2012)" which covers this topic.

They assessed 621 patients, and found similar results as the papers above - 26.2% showed evidence of traumatic dentoalveolar injury. These were patients that weren't necessarily referred for fractured teeth. They found that injury to 108 and 208 were the most common of all strategic teeth. The 26% is pretty much in line with the numbers for dentoalveolar injury in humans.

Remember, these fractures don't always have to lead to pulp exposure to cause a problem. Even a minor enamel-dentin (uncomplicated) crown fracture may expose dentin making the tooth more susceptible to endodontic disease.

In my opinion, even if an antler only caused a fracture in 1% of patients, that's still 1% too many. The fact that they are being marketed by a vet clinic makes owners think that they are suitable and safe, when there is evidence showing that they are not. If there was evidence going both ways I could see an argument.

RE: Dental chews - the evidence

Sarah Keir — Fri, 16 Oct 2020 16:10:30 GMT

Actually I'm not sure we can say that truthfully 20-27% of general population dogs have fractured teeth. Lets look at that paper you are quoting.

Saltero says @Tooth fracture in dogs is a commonly observed clinical condition, with a reported prevalence of 20–27%, although the literature quantifying this number is limited¹ (1–6).' The references cited though are:

1. A dental referral centre population in Brazil. Paper is in Portugese and google translate says it is too big to translate and I don't which bits of it are needed to be translated.

2. Duke A. Forces involved in upper fourth premolar fracture in dogs. Proceedings of the 12th Annual Veterinary Dental Forum, 1998;175. I can't access this proceedings summary - why was it not published?

3. ^Correa HL. Fracture strength analyses of canine teeth restored biologically: in vitro study. Dissertação (Mestre em Medicina Veterinária). Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, 2003;1-77. Again, I cannot access this.

4. ^Carolina Biological Supply Company, Burlington, NC. What is this reference? It sounds like a manufacturer.

5. ^Lang Dental, Wheeling, IL. What is this reference? This is a manufacturer

6. ^Instron, Norwood, MA. What is this reference? SO is this, a manufacturer of looks like machines that test forces - how can this be evidence?

Remember, I am on your side and I want people to see and treat these broken teeth but I need better evidence to change peoples minds.

RE: Dental chews - the evidence

Norman Johnston — Fri, 16 Oct 2020 15:46:39 GMT

The accepted prevalence is 20-27% of dogs in the general population with fractured teeth. The reference is in the Saltero paper.
That’s a lot of teeth to miss if your boss doesn’t see many! You can put the argument on its head. If referral practices see so much and it’s what we are sent you maybe have to worry about what we are not sent.
BTW someone mentioned rawhide is safe. There is unpublished but reliable work that puts a dry rawhide strip in the danger area for carnassial teeth and dry knotted rawhide well beyond acceptable. Once soaked in warm water until they become pulpy they are ok.

RE: Dental chews - the evidence

Sarah Keir — Fri, 16 Oct 2020 11:40:43 GMT

Thank you @Martin Hamilton, Evelyn Barbour-Hill Norman Johnston Bob Partridge Paul Cooper

Thank you all for your answers. I presented your replies to the boss today in a vets meeting and he still doesn't believe there is a problem! He says of course that you all see fractured teeth because you are dealing with a referral population. I tried discussing looking for the problem and having it presented to you by a client is rare. We all know how often dental disease is ignored/underplayed in significance by vets and dogs do not show oral pain even when severe! He also says that the study on bite forces means that we should be seeing every dog with broken teeth. I said I can't recommend to clients, just like I cannot recommend the raw chicken wings or raw meaty bones that he also recommends.

Do you have any more evidence I can present? Any other tactic I can try? I'm tempted to do an audit but it will only be cases I see as trying to get anyone else to look in a mouth properly is not going to happen.

RE: Dental chews - the evidence

Paul Cooper — Sun, 04 Oct 2020 17:21:31 GMT

The BVDA has recently produced a Position Statement on chews/ toys and diets purported to have 'dental' benefits. It can be used to guide readers to be critical of advertising claims, and ask for proof of efficacy of clinically useful dental benefits, and also of safety. The full text is:

BVDA Position Statement on 'dental' claims for diets, chews and toys. 2020
There are now numerous products in the UK marketplace for dogs and cats either directly advertising 'dental' benefits or suggesting such benefits on the packaging. Although the BVDA has promotion of oral health in animals at its core, it is important that claims made for products are backed by scientific evidence and safety data.
The BVDA would like to see all companies making claims of 'dental' benefits on their products provide evidence of both efficacy and safety, ideally in peer reviewed journals, by holding a VOHC Seal of Approval, or by supplying experimental study evidence freely upon request. Products should also be shown to be safe in the intended species.
There is poor understanding of dental disease and its causes in pet animals among owners, and some professionals. It is important to realise that dental health in animals is normally related to periodontal disease, which directly affects the gums and support of the tooth, rather than affecting the tooth directly. This is unlike humans where caries, which affects the teeth directly, is a more common form of dental disease.
To claim 'dental' benefits, products should be shown to significantly reduce plaque, which is ultimately the cause of periodontal disease. The products should also be safe to swallow, and not cause harm either to the teeth and gums, or elsewhere, such as metabolic or digestive problems.
The BVDA supports the Veterinary Oral Health Council (www.vohc.org) which independently reviews products’ evidence of effectiveness for claimed 'dental' benefits, and grants a Seal of Approval to products that pass.

RE: Dental chews - the evidence

Sarah Keir — Sun, 04 Oct 2020 14:04:43 GMT

Thank You Martin Hamilton Norman Johnston Bob Partridge I will present the evidence. As per my initial post, I'm as cynical as you Norman Johnston that vets that don't see a problem are just not looking! I love dentistry and discussing it with owners so at least half of my well pet consults include a recommendation for dental treatment. I hope to persuade my colleagues of the benefits of proper oral care for the pets under our care.

RE: Dental chews - the evidence

Bob Partridge — Sun, 04 Oct 2020 07:58:03 GMT

Already the papers have been identified.

A couple of points - VOHC does not currently assess the safety of chews etc. The data they look at is the effectiveness of the chew in reducing plaque or calculus. Part of Dr Reiter's work etc was pushing towards VOHC to start adding this to the criteria that they look at.

Time chewing (strangely) is not directly correlated to effectiveness in plaque reduction. Dr Gorrel had a paper years back on Pedigree's dental chews that did not link time chewing with effectiveness.

Dry Rawhide chews actually are too hard if you look at the bite forces used. They will also lead to the slab fractures etc seen with antlers & bones.

My simplistic view is the "Rule of Thumb" - if your thumbnail can indent a chew - it is probably fine.

Regarding your boss - given the widespread acceptance of causal link between antler chews and carnassial fractures the practice could be likely to be liable for the costs of treatment for damage caused by selling the items....... Compared to the profit generated by the sales it is a bit of a no-brainer.

All best

Bob

RE: Dental chews - the evidence

Martin Hamilton — Sat, 03 Oct 2020 20:53:13 GMT

[quote userid="2131" url="~/001/veterinary-clinical/small-animal/dentistry/f/expert-help/29389/dental-chews---the-evidence/225743#225743"]I don't quite agree with this, although it may just be the wording – it's ideal in my opinion if the dog can chew on it for hours, but it has to be a bit yielding. Rawhide chews are ideal..[/quote]

Yes, sorry Evelyn, rawhides are great! My wording was off, I just meant that it needs to be something that can yield.

RE: Dental chews - the evidence

Norman Johnston — Sat, 03 Oct 2020 20:42:05 GMT

Good replies above

The Saltero paper is the best evidence we have now apart from the anecdotal evidence from every vet dentist bar none.

When antlers became popular my practice saw a significant shift from fractured canines to carnassials. We were about 8:1 before and swapped to 1:4 almost overnight.

With regard to the spurious claim that dogs gave been chewing bones for years with no problem, I used the Russian roulette analogy. Give the dog the gun and spin the chamber. One day it’ll go off. Better to avoid the gun in the first place

Selling toys that are known to cause tooth damage is unwise at best and negligent at worst. Vets have a duty of care to their patients and this is failed by selling such objects.

RE: Dental chews - the evidence

Evelyn Barbour-Hill — Sat, 03 Oct 2020 20:23:39 GMT

[quote userid="9515" url="~/001/veterinary-clinical/small-animal/dentistry/f/expert-help/29389/dental-chews---the-evidence"] the practice owner says he has sold them for years and never seen a broken tooth because of them.[/quote]

Sorry to be cynical, but...... quite often even owner don't notice broken teeth. They don't wonder why the dog isn't playing any more, they assume he's "getting old"

there was a recent paper in Journal of Veterinary Dentistry, too, that objectively measure the force require to break an upper carnassial tooth in the usual "slab" manner.

[quote userid="16672" url="~/001/veterinary-clinical/small-animal/dentistry/f/expert-help/29389/dental-chews---the-evidence/225742#225742"]generally it recommended to give something which the dog can easily break apart rather than chew on for hours at a time without it having any give[/quote]

I don't quite agree with this, although it may just be the wording – it's ideal in my opinion if the dog can chew on it for hours, but it has to be a bit yielding. Rawhide chews are ideal..

RE: Dental chews - the evidence

Martin Hamilton — Sat, 03 Oct 2020 19:32:36 GMT

Not an expert (currently just a dentistry resident), but thought I'd reply anayway!

A recent paper by Dr Soltero-Rivera et al at U.Penn published on Frontiers (https://www.frontiersin.org/articles/10.3389/fvets.2018.00339/full) showed that the maxillary 4th premolars could withstand around 1281N of force before fracturing. Anything to chew whcih does not "give"before this force is applied when chewing is likely to result in fracture of the maxillary 4th premolar. I don't believe there is any evidence to show that antlers take more than this amount of force to break, though it would be safe to assume so - generally it recommended to give something which the dog can easily break apart rather than chew on for hours at a time without it having any give. Mars actually performed their own in-house testing on products in the USA and removed all of those which required more than 1280N to break from their pet stores following this paper. We see fractured teeth daily in our practice and as part of our history we always ask what the patients chew on - 90% of the time they are chewing Nylabones, bones or deer antlers. It's anecdotal, but I'm sure many of the experts here have a similar experience.

As for acceptable chews, I would go with those that are approved by the Verterinary Oral Helath Council (VOHC) - http://www.vohc.org/VOHCAcceptedProductsTable_Dogs.pdf. These products have demonstrated their safety and efficacy for aiding in the control of tartar or plaque (as noted on the table).

I hope this is of some use, and I look forward to seeing what the experts have to say!