Please Help me Whiten My Sensitive Teeth. Achieving beauty takes a bit of pain and endurance. The pain of whitening your teeth can get too much. I've heard horror stories about tooth sensitivity from professional whitening. Is it that bad? Yes, it can be. Dentists call these bursts "zingers,". That happens when the peroxide bleaching solution penetrates the tooth enamel. And then reaches the nerves. I experienced this sensitivity