Q. A year ago I underwent a teeth whitening process at my NHS dentist but almost immediately after the procedure I began to experience very severe pain – similar to toothache – in every tooth. This discomfort lasted for 48 hours before subsiding although I was left with extremely sensitive teeth. A few weeks later I noticed that several of my teeth – in fact five in all – were loose and I then began to experience problems with pain in these loose teeth and the surrounding gums. As a result I have had to have one of these teeth extracted and I suspect that the others will have to go too. Can you explain why the tooth whitening process should have had this devastating affect on my teeth and whethere there is anything that can be done to reverse the loosening of the teeth, cure the over-sensitivity and restore my gums back to health?