I need help with whitening my teeth Safely!?!? Please :D?

I am a Teenager and I recently stopped brushing my teeth for days at a time. Now I think of it I regret it a lot :S But now I Have started to Brush my teeth 2 times a day. The problem is that they are slightly yellow.... Is there any brand or product I can use which will whiten my teeth without any abrasives or ingredients which can damage my teeth or gums? and also if so, how long roughly would it take? And one last thing, I read About Orbit White Chewing Gum. Apparently it whitens teeth? could i have some information please :P help with any of this would be appreciated. Thank you! :D
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There aren't any successful whitening treatments which don't harm your teeth in the long run, to my knowledge. The dentist says whitening speeds up the decay process and you're likely to lose your teeth earlier on in life. Have you had a dentist checkup recently? They'll clean and polish your teeth properly and that itself can work wonders. =)
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