Abscessed Tooth: An abscessed tooth is usually a painful infection at the root of a tooth or between the gum and a tooth, most commonly caused by severe tooth decay. However, other causes include tooth trauma, such as broken or chipped or gingivitis/gum disease. These problems can cause openings in the tooth enamel, allowing bacteria to infect the tooth pulp (the tooth’s center). The infection may also spread from the tooth’s root to the bones supporting the tooth. If you think you may have an abscessed tooth, you must see a dentist right away. Untreated dental abscesses are painful and can lead to more significant health issues.