What Causes Sensitive Teeth?Our Teeth Are Protected By Enamel. When The Enamel is Worn Away Or Gums Recede, Dentin Underneath Becomes Exposed And Teeth Become Sensitive, Especially To Hot And Cold Foods. This is Called Dentin Hypersensitivity. It is Usually Experienced As We Age, But Tooth Grinding, Gum Disease, And Brushing Too Hard Can Also Contribute. Why Tom’s of Maine For Sensitive Teeth? The ingredients in Tom’s of Maine Toothpaste For Sensitive Teeth Help Reduce The incidence of Pain While Efficiently Cleaning Your Teeth. Our Active ingredient, Potassium Nitrate, is Clinically Proven Effective in Soothing Sensitive Teeth And is Derived From Naturally Occurring Deposits of Nitrate Ore Rather Than The Synthetic Nitrates Used By Other Brands. Our Safe, Low Abrasion Formula Protects Tooth Enamel While Cleaning Teeth.