Hi there ...it could be either sensitivity or some cavity ...visit your nearest dentist for proper diagnosis and plan the treatment accordingly... Take care ...!!

Hi..visit dentist. There could be a cavity which might need filling or root canal Regards

Dear friend, there is probability of 3 things.......loss of gum making tooth root exposed hence sensation on cold, ice cream, sundae. 2nd--if continuous sensation it need to be checked in to the dentist with a x-ray immediate doing to check any need to go treatment , 3rd---if there is severe gastric disorder then hypersensitivity in lower front tooth are most exposed to noxious fumes from stomach, need a protective cover, please visit the dentist else post clinical picture.

This may be dentinal hypersensitivity. . do one thing visit a near by dentist. .. and get your treatment done. .. no worries