5. Tooth decay.
Even a small cavity can eat away enough tooth enamel to expose dentin and cause sensitivity. In this case, a filling or a crown might help, according to the ADA.
6. Issues affecting your gums.
Toothbrush abrasion, pocket reduction surgery, prep work for a crown, excessive flossing, and gum disease can all lead to gum-related tooth sensitivity, Ribeiro says. Gums also recede with age, which can further increase sensitivity.