An overbite, or deep bite, occurs when the upper front teeth significantly overlap the lower front teeth when the mouth is closed. While a slight overlap is normal, excessive overlap can lead to serious oral health issues and functional impairments. Understanding the underlying cause is the first step in determining if orthognathic (jaw) surgery is necessary.
Identifying Functional Symptoms of a Severe Overbite
The need for jaw surgery is often suggested by functional problems that go beyond simple misalignment. Difficulty chewing or biting into certain foods is common when the front teeth fail to meet properly. This impairment forces the back teeth to take on excessive workload, which can lead to premature wear.
Chronic jaw pain, often related to the temporomandibular joint (TMJ), is another symptom. The misalignment places strain on the jaw joints, potentially causing headaches, earaches, or generalized facial discomfort. Visible wear and tear on the lower front teeth can also occur due to excessive contact and friction from the overlapping upper teeth.
In severe cases, the deep bite can lead to soft tissue impingement, where the lower teeth bite directly into the roof of the mouth, causing irritation and tissue damage. Speech impediments, such as difficulty pronouncing certain sounds, may also arise from improper positioning. Severe misalignment can also prevent the lips from meeting comfortably at rest, a condition known as lip incompetence.
Distinguishing Skeletal vs. Dental Overbites
The distinction between a skeletal and a dental overbite is the most important factor in determining the necessity of surgery. A dental overbite is primarily an issue of misaligned teeth positioned incorrectly within correctly sized and aligned jawbones. This problem often results from habits like prolonged thumb-sucking or crowded teeth.
A skeletal overbite (Class II Malocclusion) involves a structural discrepancy in the jawbones. This misalignment typically occurs because the lower jaw (mandible) is too small or positioned too far back, or the upper jaw (maxilla) is too prominent. Because the problem is rooted in the bone structure, it is considered a more severe and complex issue than a dental overbite.
If the jaw discrepancy is moderate to severe, the issue cannot be resolved by simply moving the teeth. Orthognathic surgery is usually required for a skeletal overbite to physically reposition the jawbones into a harmonious relationship. Treating a skeletal problem with only dental appliances will not yield a stable or functional correction.
Non-Surgical Treatment Options and Their Limitations
Many patients initially pursue non-surgical orthodontic treatment to correct an overbite. Common options include traditional metal braces, clear aligners, and specialized appliances designed to influence jaw growth in younger patients. Growth modification appliances, such as headgear or functional appliances, are most effective when used during a child’s active growth phase.
In adult patients, non-surgical options have definitive limitations, particularly for skeletal overbites. Orthodontic appliances can only move the teeth within the existing bone structure. They cannot change the fundamental size, shape, or position of the upper or lower jawbones.
If the skeletal discrepancy is too large, attempting a non-surgical correction, often called “camouflage,” can compromise the long-term stability and health of the teeth. Teeth may be moved excessively to mask the underlying jaw problem, leading to an unstable bite or periodontal issues. When the skeletal issue is moderate to severe, non-surgical treatment alone will not achieve a fully functional bite or a balanced facial profile.
The Professional Evaluation Process
The transition from self-assessment to official diagnosis begins with a consultation with an orthodontist, who evaluates the relationship between the teeth and jaw. If a skeletal issue is suspected, the orthodontist will collaborate with a maxillofacial surgeon to develop a comprehensive plan.
A thorough evaluation requires collecting detailed diagnostic records to precisely measure the misalignment. These records typically include a physical examination, digital dental impressions or models of the teeth, and specialized X-rays. Panoramic X-rays provide an overall view of the teeth and jaws, while cephalometric X-rays capture a profile image of the side of the head.
In complex cases, Cone-Beam Computed Tomography (CBCT) scans may be used to generate a three-dimensional view of the craniofacial structure. This imaging allows the surgical team to accurately assess jawbone positions, temporomandibular joints, and airway space. The final decision for surgery is based on these precise measurements and the patient’s functional complaints.