Dental crowding is one of the most common reasons patients are initially seen for orthodontic treatment. The size of the teeth, the size of the dental arch, or a combination of both are factors contributing to dental crowding. A number of approaches of expansion therapy are available to gain needed space depending upon the age of the patient, cooperation, facial form, etc.
Growth |
Patients under 6-8 years old may demonstrate an increase in dental arch length (1-3 mm) via growth after the permanent incisors erupt.
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Expansion |
Teeth in a crossbite relationship may be expanded to gain space, as well as front teeth that are tipped backwards (undertorqued). In most other instances, expanding or pushing the front teeth forward to gain space is unstable, potentially unhealthy for the bone and gums that surround the teeth, and in some instances cosmetically unappealing by making the lips appear too "full."
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Interproximal |
Slenderizing or filing the widths of the teeth by 0.5-1 mm per side can collectively gain up to 4-6 mm of space per arch.
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Tooth Loss |
The primary (baby) molars are wider than their replacement permanent bicuspids. On patients with lower baby molars still in place (usually younger than 10-12 years old), a space maintainer can be placed to preserve 4-6 mm of space as primary teeth exfoliate and permanent teeth erupt.
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Push Back/ |
Often the upper first molars are forward of their correct alignment. This may result in the blockage of teeth that erupt later (cuspids and bicuspids). By using certain orthodontic mechanics to push back or distalize the molars (neckgears, springs), space can be opened for the crowded front teeth and simultaneously correct the bite. Lower first molars may be uprighted as needed with various force systems (lip bumpers, springs, etc.). |
Primary (Baby) |
Removing baby teeth on a 6-10 year old facilitates the eruption of the developing permanent teeth. This does not necessarily mean permanent teeth will need to be extracted later.
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Permanent |
The decision to remove permanent teeth is a function of the expressed jaw-tooth size relationship. If the full compliment of adult teeth cannot be positioned in a stable, periodontally healthy, functionally sound, esthetic manner, tooth removal is indicated. Any combination of removing one to four teeth is utilized to gain space. Typically for dental crowding in the front of the mouth, mid-arch bicuspids are removed. Full-banded orthodontic treatment is then required. Between 15-18 years of age, the back of the mouth may experience crowding or "impaction" of the developing third molars, or "wisdom" teeth. Typically, these teeth are removed with no accompanying orthodontic treatment. |