Crowding or spacing of the teeth can result from an anatomical abnormality in jaw structure or from disparities between the upper and lower jaw during growth. It may also be caused by a traumatic injury affecting the jaw. An 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.
When there is too little space for all the teeth to fit into the mouth properly, crowding occurs. 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 behind or in front of 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 the crowded teeth interfere with a normal bite, they can cause bruxism, or teeth grinding, that can lead to loosened or fractured teeth, as well as temporomandibular joint pain (TMJ).
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, they may become impacted and never erupt at all. Tooth impactions have to be corrected because they can cause serious problems, such as damaging the roots of nearby teeth and interfering with the drainage of the sinus cavities.
Abnormal tooth spacing occurs when there are unnatural gaps between the teeth. Excessive space between teeth may be as problematic as tooth crowding. There are several reasons tooth spacing may occur, including:
Spaces between teeth may cause several dental and oral difficulties. The spaces may present problems with eating, overexposure of gums, and self-consciousness about facial appearance, particularly about smiling.
Most crowding or spacing can be corrected through orthodontic treatment which may involve one or more of the following:
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 arch so that all the teeth can be accommodated.