Are these any good, I am a bit worried they will damage your teeth.

Has anyone used one or have any idea which is the best and safest.

I had mine done at my dentist, it cost me £150 for a mould of my teeth, 2 syringes with the tooth whitening, basically put it in the mould every night whilst sleeping for 2 weeks. Every additional syringe is £40 or so, so i can top it up when i want. I would never buy anything off the internet, always best to ask a dentist, ask around for a good deal but i would say just pay a bit extra and get it done under the supervision of a proper dentist, they normally include the aftercare appointments in the price. You do it for 2 weeks, a top up every 6 months or so.

My dentist was shocked by the difference in shading on my teeth, it went up like 5 shades or something, the biggest difference she had ever seen Worth every penny.... which reminds me i need to top it up again.....

oh i went to a Trafalgar Dentist [http://www.scagroup.co.uk/dentistry] they are NHS and private.

Oh and PS, it does make your teeth more sensitive, and can be quite uncomfortable sometimes when you first put the moulds on your teeth with the gel in, but if i skipped a certain tooth every other day [not puttin the gel in the mould of that tooth] it turned out pretty much the same and was more bearable!!

But my dentist told me to go back if i had any big problems with sensitivity and that was all covered by the original £150 i paid. Another reason why its best to do it with a proper dentist.

Usually the home kits have a far less % of the whitening product than you can get with the professional stuff dentists use.
I had mine professionally done and got incredible results. My dentist also recommended if I had any sensitivity then use sensitive toothpaste in the moulds for 20 minutes. It helped enormously.
Keep an eye out for any Groupons/Living Social offers for dentists too, they can really knock the price down.

I top my teeth up with Crest Whitestrips and their new toothpaste too. I'm always being complimented for my teeth especially as the Americans tend to think Brits have horrible teeth

Last night I stumbled across an amazing technique called "Oil Pulling." Have a look on the Earth Clinic's web site for all the info. Basically you swill oil in your mouth swishing it in through your teeth for 5 mins a day (more can cause side effects) and over a week or more, it gets rid of all the crap that has accumulated on your teeth over the years. it comes with strict instructions not to swallow it and not to gargle, only swish round your teeth (read up fully before trying). I am giving this a go from tomorrow when I get some unrefined olive oil from the shops later, as you must do in the am before food. Looks great - anyone heard of it or done it before? Much better than the bleaching kits from the dentist full of horrible chemicals.

I used to do 'pulling' using coconut oil - the results were excellent and also caused a troublesome ganglion on my wrist to disperse - I only stopped out if sheer laziness - actually no I remember why - I really got into the whole thing and thought I'd try bee propolis as well, and it was so vile and hurt my teeth so much (I dabbed it on my gums, neat, Inadvisable) - I had to go to the dentist and have the stuff polished off and then I got out of the habit. Since I;ve been reminded I think I'll start it up again.
Thanks, I think the result is better than the toilet bowl white that is acheived with bleaching (no offense, but Shane Warne really put me off ever doing that)