I was having my teeth cleaned the other day and my hygenist new I sewed a lot over the years, and she asked me if I held pins between my teeth much. I said yes I do a lot, knew it was a bad habit. Well she told me she could see the wear on one of my front teeth from it. I thought they were starting to just crack (with age LOL) and she said no, she has seen this happen to other clients. Also cutting thread with your teeth is a bad habit. Soooooo I am trying very hard to stick the pins in a cushion from now on. Thought I would pass this along. :-D