What teeth whitening method do you think is better, laser or the gel trays?

I'm referring to whitening options from the dentist. My teeth aren't badly stained, but the over-the-counter stuff wasn't doing anything for me. I'm leaning towards laser because I'm afraid the chemicals in the gel trays getting absorbed into my gums. And which is better price wise? What are your thoughts?
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I would say gel trays, you control the length of time you bleach or Whiten your teeth, and you can do it at home when ever you want and you can touch up your teeth how ever often you need to as long as you have the custom trays, although the laser light whitens you quicker, they end up giving you the gel anyways, the material in the trays/gel you use is mostly peroxide, and when you use the laser the same stuff is applied to your teeth befor they put the light on them so eather way, peroxide is sitting on your teeth. My advice go with the trays they are less expensive than the laser and you can use them over and over again with eventually getting the same result
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