I've been putting off going to the dentist for a long time.  A very long time.  My teeth needed cleaning.  No big deal.  No pain, aches, or other problems.  But for some time now I have these two teeth that are turning black at the gum line.  Finally got tired of looking at them.  Called the dentist and went right in.  An hour and a half later I left her office with a bright new smile.  Not only did she clean and somehow magically get rid of the black, but also found and took care of two small cavities.  She's a good dentist.  And much cheaper than anything in the U.S.