First, keep in mind that a toothache is a symptom rather than a condition. It's simply tooth pain, there to tell you about a problem in your mouth. The cause of your toothache can be one of many conditions.
Tooth Abscess
An infected sore in your mouth is one of the more dangerous conditions that cause toothaches. The Academy of General Dentistry recommends seeing a dentist if your tooth hurts and any of these are present:
- Fever
- Difficulty breathing or swallowing
- Swelling around the tooth
- Pain when you bite
- A foul-tasting discharge
Left untreated, a tooth abscess can lead to an infection in your bloodstream (sepsis), which is a life-threatening emergency.
Tooth Decay
More common than an abscess is simple tooth decay. You may have a cavity, especially if your teeth are sensitive to heat or cold (assuming they weren't always that way; I still can't watch someone bite in to a popsicle without cringing).
Gum Disease
Your gums -- the soft tissue around your teeth -- could be raw or inflamed and causing pain in your mouth. You'll need to see a dentist to have the problem diagnosed and create a plan to treat it.
Source:
"What Causes a Toothache?" Feb 2007. Know Your Teeth. Academy of General Dentistry. 29 Jan 2009
