Dental etiology, In most cases toothaches are caused by problems in the tooth or jaw, such as
Pulpitis, an inflammation of the dental pulp. This can be either reversible or irreversible. Irreversible pulpitis can be identified by sensitivity and pain lasting longer than fifteen seconds, although an exception to this may exist if the tooth has been recently operated on. Teeth affected by irreversible pulpitis will need either root canal treatment or extraction of the tooth.
A special condition is barodontalgia, a dental pain evoked upon changes in barometric pressure, in otherwise asymptomatic but diseased teeth.
Dry socket, which is a condition arising after having one or more teeth extracted (especially mandibular wisdom teeth).
Some causes of toothache are the more obvious culprits such as a cracked tooth, filling or veneer, dental caries from eating acidic, sweet foods that corrode the fillings and the tooth?s protective enamel layer. This corrosion is caused from the bacteria that are present on the teeth which break down the sugars in refined foods and then excrete them in the form of acids, which then eat away at the protective enamel of the tooth, causing a cavity, infection and eventually toothache.
Cytotoxic chemotherapy-induced neuropathy
Atypical odontalgia is a form of toothache present in apparently normal teeth. This is the intra-oral equivalent of atypical facial pain. The pain, generally dull, often moves from one tooth to another for a period of 4 months to several years. The cause of atypical odontalgia is not yet clear, although some form of nerve deafferentation is plausible.
Referred pain of angina pectoris or a myocardial infarction.