Does getting your teeth whitened at the dentist really make a huge, lasting difference?

So basicly, my teeth are really yellow because when I had braces I didn't take very good care of them. I'm 16 years old. My birthday is coming up, and since I'm the reason why my teeth are in bad condition, I'm going to tell my parents (who have offered to buy me a laptop for my birthday) that I either want to get a laptop for my birthday, or have my teeth whitened at the dentist. Does that sound reasonable? Perfect white teeth is what I really, really want considering it's a big part of appearance, and I've tried the crest strips, I've tried the whitening tooth paste, none of that has worked. So what I want to know is, does teeth whitening at the dentist make a difference and if so, is it long-lasting if I maintain it with good brushing? Thanks.<3
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Yes! I bought a bleaching tray from the dentist about a year ago, and it makes a huge difference! The bleach is a lot stronger, and it lasts a lot longer. The initial expense is quite large (mine cost around $300), but once you get the trays made, it's not all that expensive to get bleach refills (about $40 for 4 treatments). Also, it is safe to bleach your teeth until you get the color that you want. You can go as white as you want to! It really works extremely well and makes a noticeable difference. I did the 8 treatments that came with my bleaching tray, and then 4 more, and my teeth are really white.
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