Malocclusion refers to a misalignment or incorrect relationship between the teeth of the upper and lower dental arches when they come together as the jaws close. Often called a “bad bite,” it is a widespread dental issue. Beyond crooked teeth, malocclusion involves the alignment of both teeth and jaws. This condition can significantly influence facial appearance and various oral functions, often leading individuals to seek orthodontic care.
Understanding Malocclusion and Its Facial Impact
When teeth do not align properly, malocclusion can lead to noticeable changes in facial aesthetics. It involves the intricate relationship between the upper and lower jaws, profoundly influencing facial structure and symmetry. For instance, it can contribute to an uneven facial appearance, where one side of the face might seem different from the other.
An improperly aligned bite can result in a recessed chin or a jaw that protrudes visibly, altering the facial profile. An overbite, where upper teeth significantly overlap the lower, might give the face a shorter, rounder appearance, or a recessed chin. Conversely, an underbite, with the lower jaw protruding, often leads to a more pronounced lower jaw and a longer-looking face.
Beyond aesthetics, malocclusion can affect several functions. Individuals may experience difficulty closing their lips naturally, leading to lip incompetence. Chewing can become challenging, impacting food breakdown and digestion, and in severe cases, it can cause jaw pain or clicking sounds. Speech patterns may also be affected, and breathing can be altered, potentially leading to mouth breathing, which can further influence jaw development.
Types of Malocclusion
Malocclusion is classified into three main types based on the relationship of the upper and lower molars. Class I malocclusion is the most common type. Here, the bite is largely normal, but issues like crowded, spaced, or rotated teeth are present.
Class II malocclusion, known as an overbite or retrognathism, occurs when the upper jaw and teeth significantly overlap the lower jaw and teeth. This severe overlap can create a noticeable facial asymmetry, making the lower jaw appear recessed. The upper front teeth may also protrude, affecting the overall profile.
Class III malocclusion, known as an underbite or prognathism, presents the opposite scenario: the lower jaw and teeth protrude beyond the upper jaw and teeth. This type often results in a prominent chin and a flatter mid-face appearance. It is frequently considered the most challenging type to correct due to the significant skeletal discrepancy.
Causes of Malocclusion
Malocclusion often has a genetic component, meaning it can be inherited. This genetic predisposition can influence the size and shape of the jaws, as well as the size and position of the teeth. For example, a mismatch between jaw and tooth size can lead to overcrowding or spacing issues.
Certain childhood habits can also contribute to the development of malocclusion. Prolonged thumb-sucking, extended pacifier use beyond age three, and persistent tongue thrusting can exert pressures that alter jaw growth and tooth positioning. Similarly, mouth breathing, often caused by obstructed airways due to allergies or enlarged tonsils, can affect facial development.
Other factors include the early or late loss of primary (baby) teeth, which can disrupt the natural eruption path of permanent teeth. Trauma to the jaw or face, such as injuries that misalign the jaw, can also lead to malocclusion. Medical conditions, syndromes, or abnormally shaped or impacted teeth can also contribute to a misaligned bite.
Treatment Options
Treatment for malocclusion often involves a range of approaches, tailored to the individual’s condition. Orthodontic treatments are a primary method, utilizing devices like traditional braces or clear aligners to gradually reposition teeth and align the jaws. Clear aligners, such as Invisalign, offer a discreet option for moving teeth into proper alignment.
For severe skeletal discrepancies, orthognathic surgery, or jaw surgery, may be recommended. This surgical procedure repositions the jawbones to achieve proper alignment and is often performed in conjunction with orthodontic treatment. Such combined approaches aim to correct both dental and skeletal issues.
In younger patients, early intervention, sometimes referred to as Phase 1 orthodontics, can guide jaw growth and prevent problems from worsening. This often occurs around age seven, allowing orthodontists to identify subtle issues and intervene while the child’s mouth and bones are still developing. Additionally, myofunctional therapy can be employed to correct harmful oral habits and muscle imbalances that contribute to malocclusion.