This is just an assumption on my part, but those liquid products will certainly not be an adequate substitute to teeth brushing. For me it's just common sense, how would we expect some liquid to help a dog remove tarter and calculus? That doesn't work for humans and it won't work for dogs. In fact, I find teeth brushing to be inadequate for my dog too. The single most effective method I've found to help my dog's teeth are giving her raw bones to chew on. In fact, if your dog was on a completely natural raw diet, it probably wouldn't need any brushing. No animals brush their teeth in the wild and they don't have these problems. The raw bones made a world of difference to me, after one use her teeth were almost completely white. Conventional kibble makes their teeth awful. Ignore the claims that kibble cleans teeth.