How can you turn brown teeth white without a dentist?

Bleaching Products. You can try over the counter bleaching gels (not rinses/toothpastes), but they don't always work well, & you often have to try several different kinds. Having a dentist give you a whitening kit doesn't cost much more, & it's always safe and effective. You should have your teeth/gums checked before you try any type to bleaching, so problems & pain don't occur. No good reason to avoid the dentist.
Dentist. The advertised products can be dangerous. Check with your dentist first!
Brush, brush. Brush and floss your teeth daily to improve the health of teeth. Healthy teeth will help your smile. Fluoride supplementation for children and drinking water with Fluoride that has been added has also shown to help prevent tooth decay.