Q. I have recently had my teeth whitened using the trays and the syringes of peroxide which you place in overnight.it cost £240 from my dentist,i noticed my teeth had lightened while i was using it but after i had finished the treatment there is not much of a difference like i had hoped.i was hoping they would be much lighter.i now think i should of maybe paid double and had the laser treatment.i am not satisfied with the outcome.thankyou.