An overbite, often referred to as a deep bite, is one of the most common bite discrepancies addressed in orthodontics. This condition describes the vertical overlap of the upper front teeth over the lower front teeth when the back teeth are closed together. While a slight overlap is normal, an excessive overlap is classified as a malocclusion (poor alignment of the teeth or jaw). The decision to pursue treatment, such as braces, depends on the severity of this overlap and the resulting effects on oral health and function. Correcting an overbite is frequently pursued not just for aesthetic reasons, but also to prevent potential long-term damage to the teeth, gums, and jaw joints.
Understanding the Types and Severity of Overbites
An overbite measures the vertical distance the upper incisors cover the lower incisors. A normal bite involves the upper teeth covering approximately 20% to 40% (2 to 4 millimeters) of the lower teeth. This slight overlap is necessary for efficient chewing and protecting soft tissues.
When the upper teeth cover more than 40% of the lower teeth, the condition is referred to as an excessive overbite or a deep bite. A deep bite is categorized as either dental or skeletal. A dental overbite arises from the misalignment or over-eruption of the teeth, often due to crowding or missing back teeth.
A skeletal overbite is caused by a structural discrepancy in the jawbones, such as an underdeveloped lower jaw or an overdeveloped upper jaw. The most severe form is known as an impinging overbite, where the lower front teeth contact the gum tissue behind the upper front teeth, creating trauma and potential damage.
Functional Consequences of Untreated Overbites
Leaving a deep overbite uncorrected can lead to significant health problems, including excessive wear on the teeth. When the upper and lower teeth overlap too much, the lower incisors can continually rub against the sensitive inner surfaces of the upper teeth, causing premature wearing of the enamel.
This constant friction can flatten or shorten the lower front teeth, increasing their susceptibility to chipping, cracking, and sensitivity to temperature changes. In cases of an impinging overbite, the lower teeth may traumatize the gum tissue and palate behind the upper teeth. This irritation can lead to chronic inflammation, gum recession, and tissue damage, compromising the long-term health of the upper front teeth.
A deep bite also places undue stress on the temporomandibular joints (TMJ), which connect the jawbone to the skull. A misaligned bite forces the jaw muscles to work harder to properly close the mouth, which can result in chronic headaches, jaw pain, and clicking or popping sounds in the joint. Furthermore, a severe skeletal overbite, where the lower jaw is set back, can sometimes restrict the airway and is associated with issues like snoring or obstructive sleep apnea.
Treatment Pathways Beyond Traditional Braces
While traditional metal braces are highly effective for correcting a deep bite, modern orthodontics offers several alternatives depending on the patient’s age and the specific cause of the malocclusion. Clear aligners, such as Invisalign, can be used for mild to moderate deep bites by incorporating features like bite ramps or power ridges into the trays. These features help intrude the upper front teeth and extrude the back teeth to open the bite vertically.
For growing patients, specific removable appliances influence jaw growth and dental development. Functional appliances, such as bite plates or expanders, can be used to widen the upper jaw and guide the lower jaw into a better position, which is a more conservative approach. These appliances work by engaging the muscles or gently applying orthopedic force to the developing bone structure to achieve vertical correction.
In cases where the overbite is severely skeletal and the patient’s growth is complete, particularly in adults, orthognathic surgery may be necessary. This procedure involves surgically repositioning the jawbones to achieve proper alignment and is typically performed in conjunction with braces or aligners to finely tune the dental occlusion. Choosing the correct method depends entirely on whether the issue is purely dental, solely skeletal, or a combination of both.
The Orthodontic Evaluation and Treatment Candidacy
The journey toward correcting an overbite begins with a comprehensive orthodontic evaluation to determine the underlying cause and severity. During the initial consultation, the orthodontist gathers diagnostic records, including panoramic and cephalometric X-rays to assess the skeletal relationship of the jaws. They may also take 3D digital scans or physical impressions to create a precise model of the teeth.
The analysis focuses on whether the overbite is due to a discrepancy in the jaw size (skeletal) or the positioning of the teeth (dental). The orthodontist will also measure the percentage of vertical overlap and the relationship of the teeth to the lips and face, which guides the final treatment plan. This detailed examination determines the patient’s candidacy for non-surgical correction, which is the preferred approach whenever possible.
If the overbite is primarily dental, the prognosis for correction with braces or clear aligners is favorable. For severe skeletal cases in adults, the need for surgical intervention is discussed based on the extent of the jaw misalignment. Ultimately, the decision to proceed with treatment is individualized, balancing the need to prevent functional issues with the patient’s aesthetic goals and overall oral health requirements.