Crowding or Spacing of the Teeth

Crowding or spacing of the teeth can result from an anatomical abnormality in jaw structure, or from a size disparity between the upper and lower jaw during growth. Crowding or spacing may also be caused by traumatic injury to the jaw. Inconsistency between the length or width of the jaw can result in an imbalance of the facial bones, muscles and teeth. An orthodontist can reposition the jaw so that, as growth continues, the bones and teeth align correctly. If the disparities are not addressed during childhood, they can result in major jaw issues that require orthognathic (jaw) surgery.

Tooth Crowding

When there is too little space for all the teeth to fit into the mouth properly, it is referred to as "crowding." Teeth may, as they try to grow in too small a space to accommodate them, become crooked, slanted, twisted or transposed, perhaps growing in an inappropriate location such as in front of or behind an adjacent tooth, or even in the upper palate.

Crowded teeth, apart from being unattractive, are more difficult to clean, resulting in increased risk of dental decay and periodontal disease. Also, because crowded teeth interfere with a normal bite, they can cause bruxism (teeth grinding), which can lead to loosened or fractured teeth, as well as temporomandibular disorders (TMD).

At times, when there is a major lack of space for incoming teeth, they may not only transpose, or begin to grow in an improper location, but become impacted and never erupt at all. Tooth impaction has to be corrected, because it can cause serious problems, such as damaging the roots of nearby teeth, and interfering with the drainage of the sinus cavities.

Tooth Spacing

Abnormal tooth spacing occurs when there are unnatural gaps between the teeth. Excessive space between teeth can be as problematic as tooth crowding. There are several reasons tooth spacing occurs, including the following:

  • Unusually small teeth
  • Missing teeth (from birth defect or injury)
  • Abnormal gum tissue
  • Impacted teeth
  • Protruding teeth

Spaces between teeth can cause several dental and oral difficulties, including eating problems; overexposure of gums; and self-consciousness about facial appearance, particularly in regard to smiling.

Correcting Crowding or Spacing

Most crowding or spacing can be corrected through orthodontic treatment that includes one or more of the following:

  • Extraction of unnecessary teeth
  • Repair or reshaping of irregular teeth
  • Bonding or capping of teeth
  • Attaching braces to the teeth to correct misalignment
  • Orthognathic surgery, in severe cases, to reshape the jaw

Braces are typically worn for 1 to 2 years, followed by the wearing of a nighttime retainer to keep the teeth correctly positioned during sleep. At times, in cases of crowding, special orthodontic devices may be used to extend the range of the dental arc, so that all the teeth can be accommodated.

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