An overbite, also called a deep bite or Class II malocclusion, occurs when the upper front teeth overlap the lower front teeth when the jaws are closed. While a small degree of overlap (typically 2 to 4 millimeters) is normal, an excessive vertical overlap can lead to complications. People seek treatment not only for appearance but also to alleviate functional issues like difficulty chewing and speaking. Untreated, a pronounced overbite can cause uneven wear on the teeth, gum recession, jaw pain, and contribute to temporomandibular joint disorders.
Addressing Overbites in Developing Jaws
Overbite correction in children focuses on growth modification, known as interceptive orthodontics or Phase I treatment. This early intervention typically begins between the ages of six and ten when the jaw bones are still actively developing. The goal is to address skeletal discrepancies by guiding the growth of the upper and lower jaws into a more balanced relationship.
The most common tools used are functional appliances designed to reposition the lower jaw forward. Fixed devices, such as the Herbst appliance, encourage advancement of the mandible. Removable options, like the Twin Block appliance, consist of two interlocking plates that posture the lower jaw in a corrected position during wear.
These appliances utilize the patient’s muscle movements to apply gentle forces to the jaw structure. This approach often minimizes the severity of the overbite, potentially reducing the need for complex procedures later. Phase I treatment usually lasts nine to eighteen months, after which the child is monitored until all permanent teeth erupt. Early correction creates a better foundation for the subsequent alignment of permanent teeth during a potential Phase II treatment.
Alignment Techniques for Fully Developed Teeth
When jaw growth is complete, correction shifts from modifying the skeletal structure to moving the teeth within the existing jawbone. This process, known as orthodontic camouflage, is effective for cases where the discrepancy is primarily dental or mild to moderate. Traditional fixed braces, using brackets bonded to the teeth connected by wires, remain a precise method for achieving necessary tooth movements.
Fixed appliances are effective for deep bite correction through incisor intrusion, which gently pushes the front teeth back into their sockets. Orthodontists achieve this using specific wire shapes, such as accentuated or reverse archwires, to flatten the vertical curve of the bite. Intermaxillary elastics (rubber bands) are often incorporated with braces, running between the upper and lower arches to apply force.
Clear aligner systems, such as Invisalign, offer a discreet alternative for correcting mild to moderate overbites. These systems use a series of custom-made, transparent trays to gradually move the teeth. For overbite correction, aligners may be paired with small, tooth-colored attachments to help execute complex movements, such as front tooth intrusion.
In cases requiring significant tooth movement, temporary anchorage devices (TADs) provide a stable anchor point for applying force. These small, medical-grade screws are temporarily placed into the jawbone to enhance control, such as retracting the upper teeth. Regardless of the appliance chosen, the retention phase requires a retainer to be worn consistently after active treatment to prevent shifting.
Surgical Solutions for Severe Skeletal Overbites
For a small percentage of patients, the overbite is caused by a severe skeletal discrepancy—a mismatch in the size or position of the jawbones—that cannot be corrected by moving teeth alone. In these instances, orthognathic surgery (corrective jaw surgery) is the only way to achieve a functional and stable bite. This procedure is typically reserved for adults whose growth has completely ceased.
The most common surgical approach for a severe overbite involving a retrusive lower jaw is mandibular advancement. This procedure involves an oral and maxillofacial surgeon repositioning the lower jawbone forward to align it correctly with the upper jaw. The jaw is then secured in its new position using small titanium plates and screws, which remain permanently integrated with the bone.
Orthognathic surgery requires pre-surgical orthodontics to align the teeth within each arch so they fit together precisely after the jaws are moved. This preparation phase can sometimes make the bite appear worse before the surgery. Following the operation, post-surgical orthodontics is necessary to fine-tune the final tooth positions and complete the correction.