What is an Overbite? Types & Causes
An overbite, also referred to as a class II malocclusion or buck teeth, occurs when the upper teeth and jaw overlap the lower teeth and jaw. It is usually a difference in jawbone alignment, when the lower jaw is back too far. This form of malocclusion is common but less common than a class I malocclusion (crowded anterior teeth). Overbites are prevalent in children and can either be genetic, due to long-term childhood habits, or both. There are two types of overbites, including:
The most common cause of an overbite is due to the size and shape of a child’s teeth and jaw (genetics). A person’s mouth can either be too large or have too little space to fit teeth properly. If left untreated, this form of malocclusion can also result in overcrowding, crooked teeth, or spaced teeth.
Childhood habits that involve pushing the tongue against the back of the teeth can cause an overbite. This includes long-term pacifier and bottle use, finger sucking, and thumb sucking. If a child already has an overbite due to genetics, these habits can worsen the condition. Breathing disorders, such as sleep apnea, are also linked to this form of malocclusion.
Other common causes of an overbite include, but are not limited to:
- Losing baby teeth prematurely without restorations, which can result in misalignment.
- Breathing disorders, such as sleep apnea, which is caused by a blockage in the upper airway while sleeping and results in breathing that repeatedly “stops” and “starts.”
- In people of all ages, frequent nail-biting and chewing on hard objects can result in an overbite.
Underbite vs. Overbite
An underbite is the opposite of an overbite and occurs when the lower jaw is pushed forward, rather than backward. Although, underbites develop due to similar factors, such as genetics.
Overbites should never go uncorrected. If children do not receive overbite treatment early, they are more likely to need jaw surgery as adults. Severe pain, jaw problems, and dental conditions can also result over time. Common complications of an untreated overbite include:
Increased Risk for Gum Disease
In a severe anterior overbite, the lower front teeth usually contact the gum line in the back of the upper front teeth. This can result in gum recession, which is when the gum tissue wears away and exposes more of a tooth or a tooth’s root. Gum disease, such as gingivitis or periodontal disease, is more likely to develop.
Severe Jaw Pain & Temporomandibular Disorders (TMD)
TMD causes severe pain and dysfunction in the jaw and muscles that control jaw movement. Without overbite treatment, TMD can form over time. Common symptoms include extreme jaw, neck, and face pain, stiffness, lockjaw, headaches, and earaches.
Other complications of untreated overbites include:
- Difficulties chewing, speaking, and swallowing
- Severe headaches and discomfort
- Crooked teeth and structural mouth changes
- Low self-esteem
How to Fix an Overbite: Common Treatment Options
The type of treatment depends on the patient’s age, the severity of misalignment, and whether the overbite is skeletal or dental. The earlier an overbite is corrected, the less likely cavities, gum disease, and TMD will develop. Orthodontists recommend waiting until a child turns seven years of age to seek treatment (once the primary teeth begin to shed and permanent teeth erupt). Treatment is still possible for adults, but options are limited since the teeth and jaw are fully developed. Depending on the patient, surgery is typically necessary for adults. Common treatment options include, but are not limited to:
Baby tooth extractions are a common overbite treatment option for young children. If a child has a smaller jaw, extracting teeth makes room for permanent teeth to grow in straight. Orthodontists do not recommend removing permanent teeth in adults. Although, in extreme cases, extractions may be necessary to allow the teeth to move easily.
Dental Braces and Retainers
Dental braces that incorporate brackets, elastics, and wires successfully treat most overbites. The devices carefully apply pressure to adjust the teeth into the correct alignment. Braces treatment lasts for 18 months to three years. The use of adjunctive intraoral appliances (Herbst appliance) in conjunction with braces, is also common.
Cervical Pull Headgear
In addition to braces, cervical pull headgear may be necessary. This type of headgear consists of a strap that is worn around the neck and attaches to the patient’s braces. The appliance holds a patient’s upper teeth and jaw in place while the lower jaw shifts forward.
Jaw Surgery (Orthognathic Surgery)
Jaw surgery for an overbite is the most expensive treatment option (up to $40,000). Adults who have severe overbites and fully developed jaws typically require surgery. Overbite surgery consists of an exam, X-rays, and general anesthesia administration. Then the jawbone is cut, reshaped, and repositioned by an oral surgeon. This type of jaw surgery, called orthognathic surgery, requires orthodontic treatment and coordination between the orthodontist and oral surgeon.