Baby had to have his teeth cleaned on a yearly basis until we switched him to a tartar control food - Prescription Diet T/D. He loves it. You can either feed it to him "full time" or give it to him as a treat, which is what we did. Now he's been a couple of years without a cleaning and still has very little buildup. There are also other tartar control foods that you can purchase from the grocery store - Iams has one, I believe.

You have to be careful because not only can the tartar buildup lead to tooth loss, it can also irritate and thus infect the gums. We lost a dog from a bacterial infection that got into her bloodstream via her gums due to tartar buildup, so it isn't just a money making scheme by our vets.