I have had tooth sensitivity for almost an year now. It happens only when I consume cold stuff. For eg. When I have my milk and cereal in school (which I sip from a cup) I feel this sharp stinging sensation in my teeth which Is so bad that I can't talk and usually berry my head in my arms till the time it stops. To be honest, my dental hygiene hasn't been at its best this year but I'm trying my best to work on it. I would love to have my milk the way I did before. Thanks a lot for helping! *I had a root canal a few years ago, if that helps.