I have a cat who is getting on in years, turning 11 this year. His vet has identified some plaque and tartar that would benefit from dental health treats. I told the vet this cat has a habit of inhaling food without chewing it, dental treats included. The cat is a ragamuffin, and not a particularly large one as the breed goes, only ~10.5 pounds – I add that to say it's more a behavioral issue than him simply being a giant. The vet's only advice was to try different treats, and they referred me to a list of approved dental treats by the Veterinary Oral Health Council.
I selected a few off of the list and sure enough they're roughly kibble sized. My cat has no trouble choking them down (but sometimes trouble hacking them back up, still unbitten and unbroken). The rest of the ones on the list that I've been able to find sizing information for are no larger, making me sure they will be no more effective. The vet has not been able to provide further guidance.
We are separately proceeding with a teeth cleaning. But an ounce of prevention being worth a pound of cure, I would still like to find a suitable, effective dental treat.
How can I get my cat to actually chew his food and treats?
Or, what dental treats are large enough that an average adult cat has to bite them to digest? Or are there dental treats/treatments that are effective without being chewed?