Toothache and Painful Gingivae (Gums)

Causes of toothache

Toothache is elicited by stimulation of the nerves in the pulp of a tooth. Common causes are:

  • Tooth decay
    The bacteria in the cavity of a decayed tooth cause inflammation of the pulp tissues, stimulating the nerves in the pulp.

    Animation showing inflammation of the pulp is being caused by tooth decay.
  • Exposure of dentine
    There are numerous microscopic tubules in the dentine which connect to the pulp. If these tubules are exposed because of the gum recession or severe tooth wear (e.g. abraded by toothbrushing or eroded by acidic food and beverages), the tooth will become sensitive, and pain will be elicited in the nerves of the pulp through these tubules when the tooth is stimulated by cold, hot, sweet or sour food or drinks.
    At the same time, the acid released by the dental plaque may also stimulate the nerves in the pulp through the exposed dentine.

    Photograph of tooth with gum recession. The exposed root of this tooth is abraded by toothbrushing.Tooth abraded by toothbrushing
  • Fractured Tooth
    The exposed dentine and/or pulp tissues resulting from fractured tooth are susceptible to any external stimuli.

    Photograph of a longitudinal section of a fractured tooth.

Causes for painful gingivae

Painful gingivae are caused by the inflammation of the tissues around the tooth. Common causes are:

  • Tooth decay
    In a severely decayed tooth, the pulp tissues may become necrotic. The bacteria of the necrotic pulp cause infection of the periodontal tissues via the root canal, leading to inflammation and formation of abscess.
  • Gum Disease
    The toxins released by the dental plaque cause inflammation of the tissues around the tooth.

    Animation of a few teeth and their periodontal tissues showing accumulation of plaque along the gum margin. The toxins released leads to red and swollen gums.
  • Pericoronitis
    Food debris and bacteria are easily trapped in the space between the crown of the wisdom tooth and the overlying gingiva (gum), resulting in the infection of the surrounding tissues (Pericoronitis).

    Animation showing an erupting lower wisdom tooth having its overlying periodontal tissues resorbed gradually until at the end the tissues become red and swollen.


Go to see a dentist to receive appropriate treatment as soon as possible: