Petzlife is mint flavored gel toothpaste that works pretty well on tartar if you use it frequently. I have it on my website if you're interested.
I just picked Sammy up from her dental. She already had bad teeth when we got her @ 10 months and she fights me so bad when I brush her teeth so at 2.5 yrs old she had to get a dental. She had 1 tiny tooth extracted. You can bet that no matter how much she fights me I am going to brush her teeth more often.
Loki just had his dental a couple months ago and he's almost 4. No extractions and he really only had 4 teeth that had tartar on them, his canines and his big molars in back. I brush his teeth a lot more thoroughly (because he lets me) and I think that helps a lot.
So, at $300 a dental plus antibiotics, pain killers, and anesthesia... BRUSH!!!
P.S. Kid toothbrushes work best and they are like 2/$1.