Thanks Amy. When I was growing up, the dentist's response to a small cavity was to drill out a large portion of the tooth and fill it with metal. By the time I was 20 I probably couldn't have gotten through a metal detector without setting off the bells and whistles. All that metal, combined with grinding my teeth as I sleep, dental fractures have been a big problem for me. When my grandchildren complain about tooth brushing, I just open my mouth and invite them to take a look - none of them think it "cool". Thanks for the info.