teeth whitening products?

does anyone no of any teeth whiteneing strips that work for ex: crest whitestrips,etc.. and do these strips cause sensitive teeth?
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i whitened my teeth for the very first time and and decided to try Aquafresh white trays and i was verrrry satisfied this was a very great product my teeth became at least 5 shades whiter and i saw some results after 2 uses and huge results after just 3 uses i only used them 4 times and my teeth are very white and am just saving the last 3 for touch ups u guess because im so satisfied it gets all around my teeth even in between. and they were not that white before because i just got my braces off and i waited a week as my orthodontist suggested to wait in order for the glue access to come off my teeth i guess. Tips: ----------when i used this product the 2nd treatment the tips of my gums became "paper white" i didn't freak out though luckily i read reviews before i used this product and is said for that to be normal. it goes away after a few minutes so i just used it every other day when that occurred i just started wiping my gums so there was no gel on them. and i put some Vaseline on my gums not too much but just enough on the parts of my gums that could not stand the gel. ---------my first treatment i had trouble keeping the bottom tray to stick to my teeth but the top one stuck on very well but the way i solved this was i used a toothpick and took the gel out of the bottom tray and put it into my retainer as my orthodontist said i could put whitening gel in my retainer (clear plastic ones that cover all teeth of course) it stuck on very well and solved all my problems this may not happen to everyone the reason it would not stick to my bottom teeth is because i had access saliva, gross i know lol ..........i would recommend this product it worked very well and was less than going to do it at the dentist and i got just as good results after just 4 uses out of 7! good luck!
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