Recently I decided to take care of my oral and dental hygiene. After visiting the dentist and having some fillings carried out I asked him whether my teeth could be whitened and how much the cost was. He replied yes and the bill was around £300! Not exactly small potatoes.Whilst I had no inclination whether the price was reasonable at the time I decided to do some research and try out certain products.I have tried the Crest strips a year or so ago and unfortunately they did very little after buying 2 weeks worth supplies and whitening every day.Upon further research it was mentioned that the active agent would be neutralized with saliva so the whitening effect wouldn't be as effective as a professional job. All it would do is froth up in your mouth and not produce noticeable results.This led me to having custom dental trays made from Ebay where they send you some putty for you to make a mould of your teeth and you send it back for them to make custom dental trays.I then ordered some Opalescence 35% from Amazon USA. EU laws unfortunately require anything over 0.1% Hydrogen Peroxide can only be carried out by dentists so I was forced to take that route.Not knowing how much I would need I just bought a 3 pack. Each pack contains 4 syringes. Also since I was going to get stung by customs which I paid for in advance during checkout I took the gamble and bought extra just in case they gave good results.In order to quantify any difference I bought a basic tooth shade guide of Ebay.I started of at a shade 9-10 (My teeth still had intrinsic tar stains from my smoking days and heavy tea stains. We Brits love tea)I finished at a shade of 2 (I only used 5 syringes to get this result. Amazing! Dazzling! Very Joey Essex lol). I decided that this was bright/white enough. Anymore then I would look like Ross from Friends.Please bear in mind monitors and taking camera pictures may distort the colours. I did not add any extra artificial effects, ISO were the same, no exposure was added but due to the difference in lighting the F stops may have been different. Pictures were taken 5 days after whitening treatment so there is no dehydration on the teeth which produce fake whiter results.I was able to use one syringe to do two treatments which I did every second day if my gums needed time to heal or my teeth were too sensitive.Prior to receiving the Opalescence I rubbed vitamin E oil onto my gums, twice a day.As long as you don't overfill the dental trays there should be minimal "spillage" onto the gums that cause chemical burn.I did find that my gums went white when spillage happened and it did cause chemical burn but it healed after a day. My pain threshold is quite high so I was able to bear it but I did give time to heal until I started treatment again.The whitening agent I could hear gently fizzing away slightly during treatment so I knew that it was doing it's magic.Common sense is just involved, if gums hurt then give it time to heal and using vitamin E which is an anti inflammatory does wonders.My whitening treatment contained 35% carbamide peroxide which is around 14% hydrogen peroxide so if it causes excessive pain then reduce the treatment time. I could only bear 30 mins at the beginning but after the second syringe I was able to withstand an hour session. The longer the whitening agent stays on your teeth the more it will be able to break down the bonds of molecules that cause stain.To combat the inevitable tooth sensitivity I used GC tooth moose which also remineralizes teeth and brushed my teeth with Biorepair plus toothpaste. Sensodyne Pronamel works equally well in repairing enamel.Things like Blue plasma lights are a placebo. They do nothing and research has proved it. You can buy a cheap one from Ebay for £3 for psychological assurance but trust me not worth wasting money on (I bought one and it did nothing).I have 6 syringes left and plenty to retouch my teeth over the year or longer to maintain brightness/whiteness.Overall I am very pleased with the outcome but would advise that anyone who wants to go down the DIY route sees a Dental professional first during their checkup and ask whether their teeth is in good condition for whitening treatment.Edit on Novermber 12th 2016.This product has a shelf life of 2 years if refrigerated. I came back to re-do my whitening after 11 months and the potency of the product has reduced greatly from when I first bought it. They were kept refrigerated as specified but don't seem to work as well as when I first received them. So buyer beware if you intend to buy in bulk and store them. Read more

I got some of this from my dentist after having invisalign and really liked it. I ordered this large quantity and some had a similar burn on the gum lines which I expected, some did not- none made any difference to my teeth at all. Very disappointing to spend over seventy dollars on junk. Read more

If you have sensitive teeth do not use this percentage and buy a much lower one! I've used the pre loaded trays w/ both 10-15% in the past and had great results with no problems. The 35 percentage is a whole new level of pain. I couldn't even place this on my lower teeth for even 30 seconds without incredible pain at all and had to immediately remove them so I didn't even try again. The top tray I could only keep on for 5 minutes the two times I used it. I love this whitening brand, which is why I ordered it, but if you have sensitive teeth definitely go for the less percentage. I wasted my money on this percentage sadly. Read more

It's hands down the best tooth whitening gel.The viscosity of the gel is very thick which helps it adhere to your teeth unlike other products that all very sloppy and leak out of the dental tray. opalescence is a great product and I highly recommend it. Read more

This whitening gel is wonderful! I have been very happy with the results and love having a white smile. When I first recieved this product I used it every other night at bedtime for almost 2 weeks until I recieved my desired color. My gums and teeth can be sensitive but I have found this whitening gel does not make it worse. Other brands that I have used made my gums sore and my teeth throb but this one is really gentle. I use it 1 to 2 times a week for maintaining my white smile. Sometimes I will use it in the morning during my shower instead of during bedtime and it works really well! I am very happy with this product. Read more

This is a very good whitener. I purchased the 35% which is way stronger than I bought from my dentist. Per my dentist the only way to get bright white, or as he called it...Hollywood white...is to get vaneers.I will stick with 35% . My teeth are much whiter than they were. Read more

Using this right now! I have been using the 20% for a while now but got tired of trying to find three or four hours to keep it in. Upped to the 35% per my friend, a former dental hygienist's, recommendation. The "three pack (12)" came with instructions and a cute little "teeth shade" chart. Not sure why everyone has questions about how long to use - it states clearly in the package that for the 35%, take it out after 30 minutes. If your teeth hurt, take a day or two off and then start again. Good luck and happy whitening! Read more

Whitener at 35% peroxide is powerful! I used it once, for 20 minutes, as directed. Used this with custom made dental trays--perfect fit. The difference in the color of my teeth was dramatic. However, my tongue was slightly "burned". Nothing terrible, but my taste buds suffered for a while... Maybe I overfilled the trays? I'm so glad I have trays that fit my teeth perfectly--to minimize overflow. Read more