Anterior overbite refers to a common dental alignment issue where the upper front teeth significantly overlap the lower front teeth when the mouth is closed. This condition, also known as a deep bite, affects many individuals and can range in severity. It represents a vertical misalignment of the teeth, distinguishing it from horizontal misalignments.
What is Anterior Overbite?
Anterior overbite occurs when the upper front teeth extend too far down over the lower front teeth. In an ideal bite, the upper front teeth should overlap the lower front teeth by only a few millimeters, typically about one-third of the lower tooth’s height. This condition can sometimes be so pronounced that the lower front teeth are completely hidden by the upper teeth.
In severe cases, known as a deep bite, the lower front teeth’s edges may even contact the gum tissue behind the upper front teeth. Overbites are categorized as complete or incomplete. A complete overbite involves the upper teeth physically touching the lower gums or palate, while an incomplete overbite means there is no contact with the opposing soft tissues.
Common Causes of Overbite
The development of an anterior overbite can be influenced by a combination of factors, often stemming from genetics. Hereditary traits play a considerable role, as jaw size and shape, as well as tooth positioning, can be passed down through families. For instance, an inherited discrepancy where the lower jaw is smaller or positioned further back than the upper jaw, or an upper jaw that is disproportionately large, can contribute to an overbite.
Certain childhood habits significantly influence jaw and tooth development. Prolonged thumb sucking or pacifier use past the age of three or four can exert pressure on developing teeth and jaws, pushing the upper front teeth forward and preventing the lower jaw from growing sufficiently. Tongue thrusting, where the tongue pushes against the front teeth during swallowing, can also contribute to this vertical overlap.
The absence of lower teeth, whether congenitally missing or lost due to trauma, can also allow the upper front teeth to over-erupt and deepen the bite.
Why Correct an Overbite?
Correcting an anterior overbite is often recommended due to a range of potential functional and aesthetic concerns that can arise if left untreated. One significant issue is the excessive wear on the lower front teeth. The constant friction and pressure from the upper teeth can cause the enamel to erode prematurely, leading to sensitivity, chipping, or even fracturing of the tooth structure over time. This wear can compromise the longevity of the affected teeth.
An uncorrected deep bite can also lead to damage to the soft tissues of the mouth. The lower front teeth, if biting directly into the gum tissue behind the upper front teeth or the roof of the mouth, can cause chronic irritation, inflammation, and even ulceration. Such continuous trauma can predispose individuals to gum recession or other periodontal issues in those specific areas.
Functional difficulties extend to chewing and biting, where an improper bite can reduce the efficiency of mastication, making it harder to properly break down food. Speech impediments, such as lisping, may also develop due to the altered positioning of the front teeth affecting tongue movement during articulation. Furthermore, an overbite can place undue stress on the temporomandibular joints (TMJ), potentially leading to jaw pain, headaches, or clicking sounds in the jaw.
Beyond the functional aspects, anterior overbites can significantly impact facial aesthetics and self-confidence. A deep overbite can alter the profile, sometimes making the chin appear receded or the lips protrude. The visual appearance of a misaligned bite can affect an individual’s self-perception and willingness to smile, influencing social interactions and overall well-being.
Treatment Approaches for Overbite
Correcting an anterior overbite typically involves various orthodontic approaches, tailored to the individual’s age and the severity of their condition. For adolescents whose jaws are still developing, functional appliances are often utilized. These devices, such as Herbst appliances or Bionators, are designed to encourage forward growth of the lower jaw or restrict the growth of the upper jaw, thereby reducing the vertical overlap. This approach leverages the natural growth potential of younger patients.
For both adolescents and adults, traditional braces remain a highly effective treatment option. Braces use brackets bonded to the teeth and connected by wires to apply continuous, gentle pressure, gradually moving teeth into their correct positions. Specific techniques, like intrusion arches or bite turbos, are often incorporated with braces to specifically address the deep bite by pushing the front teeth vertically into the jawbone or preventing full closure.
Clear aligners, such as Invisalign, offer a more discreet alternative for many patients. These custom-made, removable plastic trays exert controlled forces to incrementally shift teeth, and specific attachments or “bite ramps” can be added to the aligners to help flatten the bite.
In cases of severe skeletal discrepancies, particularly in adults where jaw growth has ceased, orthognathic surgery may be necessary in conjunction with orthodontics. This surgical procedure involves repositioning the upper jaw, lower jaw, or both, to achieve a more harmonious and functional bite relationship. Following any active orthodontic treatment, a retention phase is important. Retainers, either removable or fixed, are worn to hold the teeth in their newly corrected positions, preventing relapse and maintaining the long-term stability of the bite.