Discolored teeth can occur from a number of causes including developmental problems, use of certain drugs, trauma, infection, excessive wear of the teeth, as well as other causes. Frequently, discolored teeth are dead and require treatment.
      A common cause of discoloration occurs when a tooth dies from trauma, and the tubules of the inner tooth take up materials that stain the inside of the tooth. The material causing the staining is frequently blood or breakdown products of hemoglobin, which results in discoloration ranging from pink to purple and eventually to a brownish/gray color. Recent studies have shown that an overwhelming percentage of discolored teeth have necrotic tissue inside them. Failure to treat these teeth can result in discomfort to the patient, resorption of the root, and eventual loss of the teeth.
      Another type of discolored teeth results from developmental problems with the enamel of the teeth, causing soft, thin, brownish enamel. These teeth are sensitive and weak, and may benefit from sealants and restorative treatment.
Any discolored tooth has the potential to be uncomfortable, and should be examined by a person familiar with dental problems.

Upper canine tooth is dead and discolored compared to lower canine tooth.	Initial radiograph showing the size of the root. The entire space between the arrows is hollow and filled with necrotic debris.
Post-operative film, showing the canal ---and access site now filled.	Final picture showing the restoration (arrow), and the improvement in color after treatment.

Left upper arcade with numerous areas - - of soft, discolored enamel and exposed dentin.	After treatment involving removal of areas of soft discolored enamel, smoothing the teeth, and application of bonded resin sealants.
Left lower arcade prior to treatment.	After treatment.