dental liquids

Anyone tried these? I had a store owner swear they work today, but I'm skeptical. Chester needs clean teeth because he has a heart condition, but it's very difficult to brush them, so I'm looking for alternatives.
Thanks
Jess

I have never tried those but the vets office I work at uses a product called Oravet. When they get put under to have their teeth cleaned, a sealant kinda stuff is applied on their teeth. Then, all you have to do, is once a week put this waxy type substance on the outside of their upper teeth and it prevents tartar build up... Its relatively cheap and works really well (as long as you remember to do it once a week) We had a dog who had to have dental cleanings every 6 months because his teeth would get SO bad... Its now going on 2 years since his last dental cleaning...
AS for the other stuff... I have no idea....