An aid to explaining dentinal hypersensitivity

The hard outer enamel layer of your tooth has worn away a bit and/or your gums have receeded exposing the root and the root doesn't have the hard enamel layer. And the root surface is covered in these fluid filled tubes which run all the way into the centre of the tooth where all the nerve endings are. So when you have a sip of coffee or have something sweet or cold the fluid in these tubes gets moved and pushes around the nerve endings which you feel as sensitivity.

You can fix these by plugging the tubes with the ingredients in a sensitive toothpaste and we might consider switching you to a softer toothbrush to stop the damage to your teeth and gums.

credits to dr vivz.