Why does my pet rat grind its teeth all the time?Why should I even care?

Needs something to nibble on. The sell sticks and other things for your rat to chew on. If their incisors get too long, it can inhibit their ability to eat.

My rat has a wooden house he nibbles on and I keep a small piece of wood in his cage as well. I've also heard that a small peice of bick is good for their claws, but I haven't yet done that.

A rat's incisors (front teeth) never stop growing. Maybe your ratty's teeth are getting too long. He probably needs something to gnaw on. McGentrix knows about such matters.

I actually have a pet rat as well, and I wondered that too because I just recently got him. Well, the websites I looked up said they do that when they are happy. Also like everyone said, you should buy those little wood colored blocks for small pets from any store, they're for rabbits,rats, etc. because their teeth do not stop growing and they will have problems if they don't have something hard to chew on. I don't know if you ever have had a bird but it's the same thing with their beaks. It's exactly like when people file there fingernails down! The would blocks are cheap like 3 dollars, if you have those though and it chews them I wouldn't worry about it. Oh and also, if rats are chewing on the bars of their cage it is a sign of them trying to file their teeth down. Hope this helps.

Do rodents teeth keep growing throughout their lives ? If thats the case, then I can understand them grinding them.

Yup, farmerman, the incisors keep growing--in all rodents.

That is not a bad thing to worry about. Rats teeth grow very fast. About five inches a year and I read in a book that they can chew trough just about anything. If you really want your rat to stop you should get somthing for it to chew on.