Stains can be due to tobacco, gutka, pan, alcohol and smoking
. Avoid if you take these as they cause some serious problems like cancer
, submucous fibrosis, leukoplakia.
There are no such toothpaste which makes the teeth white from yellow..You need to go for professional cleaning and bleaching
. Apply mixture of baking soda and lemon juice. Rub on stained surface and rince repeat this after one week.