Hi,
That coke and tooth, coke and nails stuff is folklore:
http://www.snopes.com/cokelore/tooth.asp
My son and I tried it with one of his teeth when he was in elementary school. After a month the tooth was no different in size or weight, only more stained. He got a bad mark from the teacher, I got a bad mark from my son....
I use mineral spirits, mostly.
Patrick