Braces are a comprehensive orthodontic approach used to correct an overbite, a common form of malocclusion. This detailed process involves applying gentle, continuous forces to reposition teeth and, in some cases, modify jaw alignment. Understanding how these forces work reveals the effectiveness of modern orthodontic treatment. The goal is to achieve a balanced bite, which improves function, reduces dental wear, and enhances overall oral health.
Understanding the Overbite
An overbite, technically termed a deep bite, is an excessive vertical overlap of the upper front teeth over the lower front teeth. While a small degree of overlap is normal, an overbite occurs when this overlap is too pronounced, sometimes obscuring the lower teeth when biting down. This misalignment is categorized into two types: dental and skeletal.
A dental overbite results from the mispositioning of the teeth within jaws that are otherwise normally aligned, often due to crowding or habits like prolonged thumb-sucking. Conversely, a skeletal overbite originates from an imbalance in the size or position of the jawbones, such as an upper jaw that is too far forward or a lower jaw that is underdeveloped. The distinction between these types dictates the specific tools and techniques an orthodontist will use for correction.
How Brackets and Wires Initiate Movement
Traditional fixed braces establish a foundation of alignment using brackets bonded to the teeth and an archwire threaded through them. The archwire, often made of a nickel-titanium alloy, applies a light, continuous force due to its shape memory.
This steady pressure signals a biological response known as bone remodeling, involving two specialized cell types: osteoclasts and osteoblasts. On the compression side, osteoclasts break down the alveolar bone, creating space for movement. Simultaneously, osteoblasts generate new bone tissue on the tension side to stabilize the tooth in its new position. This cyclical process allows the teeth to move gradually into their corrected positions.
Specialized Appliances for Vertical Correction
Brackets and wires handle general alignment, but specific appliances address the complex vertical and jaw discrepancies of an overbite.
Appliances for Dental Overbites
For deep dental overbites, bite turbos or bite plates are often bonded to the back of the upper front teeth or on the biting surfaces of the back molars. These temporary platforms prevent the upper and lower front teeth from fully contacting. This protects the lower brackets and “disoccludes” the bite, allowing the back teeth to erupt or the front teeth to be gently intruded out of the deep overlap.
Interarch elastics, or rubber bands, apply targeted force vectors to correct the bite. They stretch between specific hooks on the upper and lower braces, creating a diagonal pull that encourages the upper teeth to move backward and the lower teeth to move forward. Consistent wear is necessary, as elastics provide the sustained force required to shift the dental arches into proper alignment.
Appliances for Skeletal Overbites
For overbites with a skeletal component, especially in growing patients, functional appliances like the Herbst or Mandibular Anterior Repositioning Appliance (MARA) are used. These fixed devices attach to the back teeth and mechanically hold the lower jaw in a more forward position. By consistently posturing the mandible forward, these appliances encourage the lower jaw to grow into a balanced relationship with the upper jaw, correcting the underlying skeletal discrepancy.
Treatment Timeline and Post-Braces Retention
Correcting an overbite typically involves several distinct phases, and the duration is highly individualized, often ranging from 18 to 36 months for moderate to severe cases. The initial phase focuses on leveling and alignment, where the archwires work to straighten teeth and reduce crowding. The subsequent correction phase introduces specialized tools, like elastics or functional appliances, to actively reduce the vertical overlap and achieve the correct bite relationship.
Once active treatment concludes, the patient transitions into the retention stage. Retainers, which can be fixed (a wire bonded behind the teeth) or removable (a custom-fitted appliance), are prescribed to hold the teeth in their newly corrected alignment. Retention is necessary because the bone and soft tissues surrounding the teeth need time to stabilize and reorganize around the new positions. Without diligent retainer use, the teeth tend to shift back toward their original misalignment, known as relapse.