Tooth whitening used to work for me, now it doesn't anymore. what is happening?

Abused: You permanently abused the enamel of the tooth. Get a good dentist to evaluate your situation and give you some options to do at this time. Do not be surprised if it will cost in the many thousands of dollars.

No sure: You may have hit a point at which your teeth are as white as they're going to get from bleaching. Your whitening gel may be old and expired. Check with your dentist to see what your using and how you're using it. There are stronger take home whitening gels available now as well as in office only strength solutions.

Professional advice: There are limits to everything. You may expect more of a change than is possible. We often notice big changes but not little ones. The best one to give you good advice on this issue and what alternatives you have, if any, is your dentist. Schedule a visit and see what he\she thinks about this issue.

Professionally done?: Have professionally done by your dentist and then follow his or her instructions on how to keep them white and mentaine that through regular check ups and the use of bleaching trays after cleanings.

You're done...: It seems your teeth have whitened as much as they possibly can. If you want more whitening you may well need to consider porcelain veneers.