teeth whitening... Anyone know any tricks?

Anyone know any effective/cheap whitening kits or tricks (i brush frequently, however I am seeking a whiter smile) ?
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GImmics like Baking Soda or all those whitening tooth pastes that cost double and all they add is baking soda (some kind of abrasive ingredients) dont work. It does for some people who have early coffee stains (hasnt seeped into the pore too far). It seems like you can try hydrogen pyroxide in a bottle (at your local pharmacy over the counter). It has 3% and make sure u dont swallow...it will eventualyl whiten your teeth but will take long since it isnt kept on your teeth for long and it is exposed to water... The most effective, but most expensive (for some strange reason) is a higher dose of hydrogen pyroxide that is only given by perscription by a dentist specifically for whitening...but the real cost comes from them making these molds of your teeth (trays) so you can put the gel like hydrogen pyr. in them to sit on your teeth for several minutes. Why trays cost $300-$400 is total scam since one can make it at home for $10 max....i guess everyone wants to make money. After you whiten your teeth You might want to cut back on those staining agents too..such as coffee, or even certain fruits that have citric acid (if i recall)...I believe there is a thing called tannens (sp?) in fruits/veg that promote staning too but we need to eat them to stay healthy so its a catch-22. The best you can do is to make sure you brush your teeth after dowsing your teeth with those staining agents...
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