Severe pain and sensitivity in tooth ? - Time to visit your nearby Dentist !! Tooth Pain General Causes of tooth pain and sensitivity: Pain and sensitivity can be caused by an exposed nerve that may caused due to Gum disease , a lost filling or a crown , smoking and tobacco use, misaligned teeth , brushing with an hard-bristled toothbrush and tooth grinding etc. Next steps: - It is not suggestible to keep this condition of exposed tooth nerve untreated as problem doesn't resolves by itself and untreated exposed nerve may worsens if the disease continues resulting in serious gum infection ( Periodontitis ) and possibly bone loss in the jaw . - In most cases you may be also experiencing swelling along with pain and sensitivity . For that rinse your mouth with warm salt water to reduce the swelling and immediately visit your dentist nearby before infection spreads or worsen. To know more about tooth pain and sensitivity or its clinical treatment