Two ways to whiten your teeth
You can buy over-the-counter teeth-whitening products, and some people regard this as a cheaper alternative to professional teeth whitening. But our teeth whiten only while they're in contact with the whitening gel. So whitening toothpaste is not an effective method, since we only brush our teeth for a few minutes each day.

Further, our teeth whiten according to the strength of the whitening gel. Over-the-counter gels have a lower concentration of the whitening agent (usually hydrogen peroxide), and are not as effective is professional-strength gels.

So your two good options are:
· A professional system such as BriteSmile, at your cosmetic dentist's office; or
· A take-home kit such as NiteWhite, with custom trays made by your cosmetic dentist

Done in the office
Do you have one hour to spare? That's all you need to transform your smile. The BriteSmile gel is applied to your teeth. It's then activated by a specialized blue light (not a laser). For 20 minutes you can relax and watch TV on the ceiling, or listen to music, or sleep.
· This is done 3 times, and at the end of the hour you'll look like a new person, your teeth as much as 14 shades whiter
· There'll be Before and After photos taken, which you can take home with you

There'll be little or no tooth sensitivity afterwards, because the BriteSmileÔ gel contains a lower concentration of hydrogen peroxide than other tooth whitening systems, just 15%. It's buffered to be a neutral pH value, and contains other ingredients to prevent tooth dehydration.

Done at home
The Nite White at-home kit is easy to use. Your cosmetic dentist would first take an impression of your teeth, and make you a set of custom trays. The kit comes with 9 syringes of gel, each syringe marked to indicate how much gel to use each time. You simply squeeze the right little amount into the trays and wear them for 1 to 2 hours.
· If you prefer, you can wear them overnight. The gel won't over-treat your teeth overnight because it stops working after a couple of hours. But if your daily routine doesn't allow for wearing the trays, overnight is a good option.
· The trays are not obvious. Most people won't notice that you have them in.
· If your teeth become a little cold sensitive, the kit provides some gel to reduce that sensitivity.
· Nite White kits come with varying strengths of carbamide peroxide as the whitening agent. Your cosmetic dentist will know which one to choose for you.

Over a week, or maybe 2 or 3 weeks, your teeth will brighten up dramatically, all done at your own convenience.