My son 22 months.he never allows me to brush his teeth.they look yellow now.will it ever be white as before if he doesn't brush.how to brush his teeth?

Brush his teeth. : He is 22 months old and he won't let you brush his teeth? You must insist on cleaning his teeth, but be gentle about it. Use either a soft bristle tooth brush or a clean wash cloth dipped in warm water. After you get the teeth clean, they should be white again. If not, please have him checked by a dentist. He may have some cavities.

Be a parent: Sometimes you simply have to assert your will with a child. You can't let the child exhibit behavior that is harmful to themselves. You will have to brush your child's teeth 2x/day for him, whether he likes it or not. Go see a pediatric dental specialist (should have gone at age 1) for help motivating, caring, and helping your child onto the right path. Sometimes being a parent is hard.