Dr. Holmstrom spoke at length about tooth resorption in cats,  a common and painful malady that every vet sees almost daily in practice. Unfortunately these poor cat's affected teeth need to be extracted as they are painful and they never seem to get better. Worse yet we really don't know what causes these teeth to go bad, I've always chalked it up to just plain old bad luck. Two new theories were put forward and I think together they may go a long way towards explaining tooth resorption in cats.

Here's a link you can go to link you can go to that shows the problem. 

You can also find this in an encyclopedia section of my website  under links we love at LosAltosvet.com.

The name has changed over the years but the disease has remained the same. "Cavities" worked well I thought for most of the 1970's and everybody was happy with that name. Then in the 1980's, when veterinary dentistry really got going as a specialty,  those wacky specialists named the same lesions  "neck lesions" because they were found at the neck of the tooth more often than the crown or the root. Turns out we now know they can often be found on the root or crown so that old name is no more. In the 1990's the same problem was renamed and voila,  "feline oral resorptive lesions" ( FORL's) were born.  Still too easy to say and remember the next new name was "feline odontoclastic resorptive lesions".  I was not much affected by the name change because I just kept on writing down FORL in my records. This year the  fourth new name is just plain old "tooth resorption". Most cat owners, being reasonable people, still call them cavities.  Why all the name changes, you ask? So vets can go to conferences at swanky joints in Las Vegas, hob nob with veterinary dental specialists and keep up with the changes in nomenclature, of course.  But I digress. 

Vitamin D plays many complex roles in the body but it is fundamentally involved with calcium and phosphorus metabolism. It is available in the diet and is activated by sunlight. The new theories link tooth resorption to vitamin D in two different ways, diet and sunlight.

We may be feeding our pet cats too much vitamin D.  Dr. Holmstrom cited an article where commercial cat foods were measured and they found that 41% of them had 30 times the okay level of vitamin D. Pet food manufacturers are now taking steps to correct this and I hope it will result in feeding healthier cat foods and seeing fewer cats with tooth resorption in the near future. Good luck finding that info on pet food labels. Here is a link to a good pet store who can help you find the foods that have OK levels of vitamin D.

The other study Dr. Holmstrom mentioned found that tooth resorption is not seen as frequently in outdoor cats. We don't know why that is but since vitamin D is activated by sunlight it's entirely plausible that sunlight- or rather the lack of sunlight-  predisposes cats to tooth resorption.

The rest of Dr. Holmstrom's lectures that day were devoted to extracting teeth and I won't bother you with the technical information that I find so helpful with my efforts to manage these distressing cases. For now my advice is to try and find cat foods that meet but don't exceed vitamin D levels recommended for cats.  I am not sure if letting your cat outdoors is worth the risk, I have always been a huge proponent of keeping suburban cats 100% indoors as there are many things out there that are much worse than potential  tooth resorption. Try to get your kitty cats some sunlight several times a week, especially if you have had  previous tooth resorption problem (cavity).