I have one. If you drink alot of coffee/soft drinks/smoke, bush your teeth with a water and bicarb of soda mixed into a paste(i think its called baking soda in the US) and then finish it off with toothpaste, if your teeth need a good deep clean this is amazing!

If you drink lots of soft drinks like cola and other acidic drinks rinse your mouth with a mouthwash or bicarb of soda and water mix (more waterly than the paste) as this will nutralise your mouth so its not acidic which will break down your enamel.

NEVER drink fizzy drinks before bed or orange juice also as they make your mouth acidic and when you are alseep you dont produce enough saliva to protect your teeth and it will make them weak.