The question of whether braces alone can correct a jaw issue hinges entirely on the underlying source of the misalignment. The jaw is composed of two primary bones: the maxilla (fixed upper jaw) and the mandible (movable lower jaw). When the bite is misaligned, this condition, known as a malocclusion, can stem from issues with the teeth, the bones, or both structures. Determining the nature of the problem guides the treatment path toward either orthodontic correction or surgical intervention.
Understanding Dental and Skeletal Misalignment
Misalignment issues are categorized based on whether the problem lies with the positioning of the teeth or the size and relationship of the jaw bones. A dental malocclusion occurs when the teeth are misaligned, crowded, or spaced improperly, but the upper and lower jaw bones are generally well-sized and positioned relative to each other. This is often classified as a Class I malocclusion, where the bite is largely correct, but individual teeth are out of place.
A skeletal malocclusion involves a discrepancy in the size, shape, or position of the maxilla and mandible. This structural problem can manifest as a Class II malocclusion, where the upper jaw or teeth protrude significantly past the lower jaw, often creating an overjet or deep overbite. Conversely, a Class III malocclusion involves the lower jaw or teeth extending forward past the upper jaw, resulting in an underbite. Because the jaw bones themselves are improperly positioned, a skeletal issue presents a greater challenge for correction without surgery.
How Braces Influence Jaw Alignment
Braces are highly effective at correcting dental malocclusions by applying gentle, constant pressure to move teeth within the existing jaw structure. The brackets and wires stimulate the body to break down and rebuild the bone surrounding the tooth root, allowing the tooth to shift into a new position. This process directly addresses issues like crowding, spacing, and minor bite irregularities to improve the occlusion.
The influence of braces on the jaw bones is strongest in younger patients whose skeletal growth plates are still active during adolescence. During this time, interceptive orthodontics, known as growth modification, can be used to guide the development of the jaw bones. Appliances like palatal expanders can widen a narrow maxilla, while functional appliances can help guide the growth of the mandible.
For children and teenagers, this guidance can sometimes correct moderate skeletal discrepancies, potentially preventing the need for future jaw surgery. By addressing the underlying jaw relationship early, the orthodontist creates a more balanced foundation for the permanent teeth to align correctly. In adults, however, where the jaw bones are fully developed and fused, braces are limited to moving only the teeth.
Correcting the alignment of the teeth can also have a positive, secondary effect on the temporomandibular joint (TMJ). A misaligned bite often causes excessive strain on the jaw joint and its surrounding muscles, leading to discomfort and pain. By moving the teeth into a proper relationship, braces often alleviate this strain, reducing the severity of TMJ symptoms related to the bite problem.
When Orthognathic Surgery Becomes Necessary
Orthognathic surgery, commonly known as corrective jaw surgery, becomes necessary when a skeletal malocclusion is too severe for orthodontic appliances alone. This is particularly true for adults who have completed skeletal growth and whose jaw bones can no longer be modified by growth-guiding appliances. The procedure involves physically cutting and repositioning the maxilla, the mandible, or both, to achieve proper alignment and facial balance.
Conditions requiring surgery include large discrepancies in jaw size, such as a severe Class II overjet or a pronounced Class III underbite, or significant facial asymmetry. Surgery is not an alternative to braces in these severe cases; rather, it is a combined treatment approach. The first phase requires pre-surgical orthodontics, which involves wearing braces to straighten the teeth.
This pre-surgical phase is crucial because the teeth must be aligned perfectly within their respective jaws so they can fit together correctly once the surgeon moves the jaw bones. The teeth may look worse during this initial orthodontic phase as they are moved out of their compensating positions. After the surgery repositions the jaw, a final phase of orthodontics ensures the teeth settle into the newly corrected bite relationship.