Malocclusion, or the misalignment of teeth and jaws, is a widespread condition. The deep bite is a common type of bite discrepancy involving an excessive vertical overlap between the upper and lower front teeth when the jaw is closed. While often viewed as purely an aesthetic concern, a deep bite can indicate underlying issues that impact the entire oral system. Understanding this misalignment and its potential effects on dental health is crucial for informed treatment decisions.
Defining the Deep Bite
The deep bite, clinically known as excessive overbite, is defined by the vertical relationship between the upper and lower incisors. In an ideal bite, the upper front teeth vertically overlap the lower front teeth by approximately 30 to 40% of the lower crown height. This slight overlap ensures proper function and protection.
A deep bite occurs when the upper teeth cover the lower teeth far beyond this ideal range, sometimes obscuring them completely. In severe cases, the lower incisors may contact the gum tissue on the roof of the mouth (the palate) when the jaws are closed. The condition can arise from a discrepancy in the size or position of the jawbones (skeletal component) or from the positioning and eruption of the teeth (dental component).
The Health Consequences of Untreated Deep Bite
Leaving a deep bite untreated can initiate mechanical problems impacting the teeth, gums, and jaw joints. The most direct consequence is accelerated wear of the tooth enamel. Because the vertical overlap is excessive, the incisal edges of the lower front teeth forcefully contact the back surfaces of the upper front teeth. This grinding contact leads to chipping, flattening, and premature erosion on both the upper and lower teeth. In adults, this wear often compromises the tooth structure, requiring restorative intervention to rebuild lost material.
The gum tissue is particularly vulnerable to trauma in a severe deep bite. The lower incisors can impinge directly into the soft tissue of the upper palate, leading to chronic inflammation, irritation, and the development of sores or ulcers. This constant injury, sometimes referred to as traumatic overbite, can cause gum recession and compromise the health of the bone supporting the upper front teeth.
A deep bite can also contribute to issues with the temporomandibular joints (TMJ), which connect the jawbone to the skull. The improper positioning of the teeth forces the lower jaw into an unnatural or strained position, affecting the chewing muscles. This strain can manifest as chronic headaches, facial pain, or joint dysfunction characterized by clicking, popping, or difficulty opening the mouth.
The malocclusion affects the function and appearance of the face. Some patients experience difficulty chewing certain foods because the teeth do not meet correctly to shear or grind the food. A deep bite can affect the lower facial height, sometimes giving the chin a retruded appearance or leading to a shortened facial profile.
Treatment Approaches for Deep Bite Correction
Correcting a deep bite involves repositioning the teeth or jaws to establish a balanced vertical relationship. The most common approach is orthodontic treatment, which employs several mechanisms to achieve the desired bite opening. Traditional fixed braces and clear aligner therapy are frequently used to apply controlled forces to the teeth.
The goal of orthodontic correction is to reduce the vertical overlap through two main movements. The first is the intrusion of the incisors, which involves pushing the upper and/or lower front teeth further into the jawbone. The second is the extrusion of the posterior teeth, allowing the back teeth to move slightly out of the jawbone, effectively opening the bite in the front.
Specialized orthodontic devices are often used in conjunction with braces or aligners to facilitate these movements. Bite turbos or bite planes, for instance, are small ramps placed on the back of the front teeth or the biting surfaces of the back teeth. These appliances temporarily prevent the front teeth from fully contacting each other, allowing the posterior teeth to erupt and thereby open the deep bite.
For adult patients with significant tooth wear from an untreated deep bite, restorative dentistry plays a role in the correction process. The lost tooth structure must be rebuilt to restore the proper shape, height, and function of the teeth. Procedures such as composite bonding, porcelain veneers, or crowns can be used to increase the vertical dimension of occlusion, effectively raising the bite to its correct level.
In cases where the deep bite is rooted in a jaw structure discrepancy, a combined approach involving orthognathic surgery may be necessary. This surgical intervention is reserved for skeletal issues that cannot be corrected by tooth movement alone. The surgery physically repositions the jawbones to create the correct alignment, working in partnership with pre- and post-surgical orthodontics.
Intervention during childhood or adolescence is often preferred because developing jaws allow for easier modification of bone growth patterns. Regardless of the patient’s age, a comprehensive treatment plan aims for a stable occlusion that prevents future wear, protects the gum tissues, and promotes long-term jaw health.