Do it yourself dental care for your cat....? Drooling?

My cat has a canine tooth that has a lot of yellowish/brown plaque at the top, and her gum is red. It has been this way for quite awhile. I think it has been bothering her and I cant afford a teeth cleaning from the vet. I had a collar on her about a year ago and somehow she got the metal loop that held her nametag on caught in her teeth and I didnt discover her perdicament until the next morning. She lost her tiny front teeth from this. Does anyone have any tips on do it yourself dental care for pets? Should I buy some dental tools like a scraper? I have tried brushing her teeth with pet toothpaste, but it didnt do much. She and my other cat also drool when they are being petted. I read somewhere that some cats sometimes do this when they are happy, does anyone know anything about that? Could it be because her tooth is hurting her? The other cats teeth are fine.
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If there is a lot of tarter on her teeth, no matter what you do, you can not remove it. The best you can do at this point, without getting the vet involved, is to "manage" the buildup of new tarter. This can be done with cat toothpaste, liek you are talking about. I would NOT, repeat NOT, purchase a "scraper" and attempt to scrape the tarter off. This is dangerous and can cause them a LOT of pain. Your best bet is to at least get it checked out by a vet to see if the tooth/gum is infected. If this is the case, they will probably prescribe/send you home with an antibiotic, which should help, if it is an infection. Otherwise, the doctor can give you a better feel as to what is going on. If you don't have the money, save up- it really is needed! Go without coffee for a week- you'll save some money there!
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