While the primary goal of braces is to align teeth and correct the bite, the mechanical forces they exert can subtly influence the surrounding bone and soft tissues. These changes typically contribute to a more harmonious facial appearance, but they rarely alter the skeletal length of the face. Understanding the difference between a minor dental change and a major skeletal one is the first step in addressing this concern.
The Direct Answer: Braces and Facial Length Perception
Standard orthodontic treatment does not lengthen the skeletal structure of the face. The perception of facial length change often stems from alterations in the soft tissues, such as the lips and cheeks, which are supported by the teeth and jawbones. When teeth are moved, the soft tissue drape over the bone changes, which subtly refines the facial profile.
For instance, the retraction of protruding upper teeth can cause the lips to relax and appear less prominent, altering the profile view. This change in lip posture and profile projection can be mistakenly interpreted as an overall lengthening of the face. In reality, the skeletal dimensions remain stable, especially in adults where bone growth is complete.
How Orthodontic Mechanics Influence Vertical Height
Orthodontic mechanics can directly affect the vertical dimension, specifically the height of the lower third of the face, by controlling the position of the back teeth, or molars. The vertical position of the molars acts like a fulcrum, influencing the rotation of the mandible, or lower jaw. This rotation is the mechanism by which the lower facial height can be slightly modified.
One technique is molar intrusion, which involves gently pushing the molars further into the jawbone. This action can cause the mandible to rotate slightly forward and upward (a counter-clockwise rotation), which may subtly decrease the lower facial height and often helps in correcting a deep bite. Conversely, molar extrusion involves pulling the molars down, causing the jaw to rotate backward and downward (a clockwise rotation). This movement increases the lower facial height and is sometimes utilized to help close an anterior open bite. These movements are precisely planned by the orthodontist to correct functional issues.
Factors That Determine Facial Vertical Dimension
The overall vertical dimension of the face is primarily determined by skeletal and genetic factors that braces alone cannot fundamentally change. Orthodontic treatment mainly influences the lower third of the face.
The true drivers of facial length are the size and orientation of the maxilla (upper jaw) and the mandible (lower jaw). A person’s natural skeletal growth pattern, such as a high-angle (vertical) or low-angle (horizontal) growth pattern, is genetically determined and is the dominant factor in facial length. While the position of the teeth supports the vertical dimension of occlusion, the underlying bone structure is the primary determinant. Significant changes to the skeletal vertical dimension typically require orthognathic surgery, which is a procedure far more extensive than traditional braces.
Aesthetic Changes Beyond Facial Length
Braces can induce several aesthetic changes that contribute to a refined facial appearance. Alignment of the teeth and correction of the bite can significantly improve the definition of the jawline and chin. For example, correcting an overbite can bring the lower jaw into a more balanced position, making a previously recessed chin appear more prominent and defined.
Changes in lip support are also a common outcome, as teeth are moved to their ideal position. Repositioning flared or protruding teeth can allow the lips to rest more naturally and reduce strain when the mouth is closed. This subtle shift in lip posture can enhance the profile, often leading to a perception of improved facial symmetry and a more balanced look overall.