Illustrations: How A Tooth Decays

  1. Healthy Tooth
    Healthy Tooth
    Enamel is the hard outer crystal-like layer. Dentin is the softer layer beneath the enamel. The pulp chamber contains nerves and blood vessels and is considered the living part of the tooth.
  2. White Spots
    White Spots
    Bacteria that are exposed to sugars or carbohydrates can make acid, which attacks the crystal-like substance in the tooth's outer surface. This process is known as demineralization. The first sign of this is a chalky white spot. At this stage, the decay process can be reversed. Using fluorides at home and in the dental office can help the tooth repair itself.
  3. Enamel Decay
    Enamel Decay
    Demineralization continues. Enamel starts to break down. Once the enamel surface is broken, the tooth can no longer repair itself. The cavity has to be cleaned and restored by a dentist.
  4. Dentin Decay
    Dentin Decay
    The decay reaches into the dentin where it can spread and undermine the enamel.
  5. Pulp Involvement
    Pulp Involvement
    If decay is left untreated, it will reach the tooth's pulp, which contains nerves and blood vessels. The pulp becomes infected. An abscess (swelling) or a fistula (opening to the surface of the gum) can form in the soft tissues.

*Illustrations created by Simple Steps designer Lynda Buchhalter


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Reviewed by the faculty of Columbia University College of Dental Medicine.