People often ask me, “ Is tooth whitening safe?”  Yes.  Extensive research and clinical studies indicate that whitening teeth under the supervision of a dentist is safe.  In fact, many dentists consider whitening the safest cosmetic dental procedure available.  So, what is whitening?   Whitening is a process that lightens discolorations of the enamel and dentin.  There are many causes of discolorations.  The…