An overbite is a common dental alignment issue where the upper front teeth extend vertically over the lower front teeth. While a slight overlap is considered normal and even beneficial for proper tooth function, an excessive overbite can lead to various oral health concerns.
Understanding an Overbite
An overbite describes a vertical misalignment where the upper teeth overlap the lower teeth more than they should. While a small amount of vertical overlap is typical for a healthy bite, typically 2 to 4 millimeters or about 20-30% coverage of the lower teeth, an overlap exceeding this range is classified as an overbite. Orthodontists measure this overlap in millimeters or as a percentage of the lower incisor’s height to determine the severity of the condition.
Causes of Overbites
Several factors can contribute to the development of an overbite. Genetic factors play a significant role, as inherited jaw shapes and sizes can lead to an imbalance where the upper jaw is overdeveloped or the lower jaw is underdeveloped.
Childhood habits also frequently contribute to overbite development. Prolonged thumb sucking or pacifier use past the age of three or four can exert pressure that pushes the upper teeth forward and affects jaw growth. Tongue thrusting, where the tongue pushes against the front teeth during swallowing, can also gradually shift teeth out of alignment. Other habits like excessive nail biting or chronic teeth grinding (bruxism) may also influence tooth positioning.
Potential Consequences of an Overbite
An untreated overbite can lead to a range of functional and health issues. One common consequence is excessive wear on tooth enamel. This constant friction can lead to chipping, cracking, or premature erosion of tooth surfaces. In severe cases, the lower teeth might even bite into the gum tissue behind the upper front teeth, causing irritation or injury to the roof of the mouth.
Overbites can also impact jaw function, potentially leading to discomfort and pain in the temporomandibular joint (TMJ), which connects the jaw to the skull. This strain can manifest as jaw pain, clicking or popping sounds in the jaw, and even headaches or earaches. Speech impediments, such as lisping, may arise due to the improper positioning of the teeth affecting tongue movement. Furthermore, individuals with an overbite might experience difficulty with chewing certain foods efficiently.
Beyond direct dental and jaw problems, an overbite can increase the risk of gum disease due to challenges in maintaining proper oral hygiene around misaligned teeth. In some instances, a significant overbite can also contribute to breathing difficulties, including an increased risk of sleep apnea, as the jaw position may obstruct the airway.
Correction and Management of Overbites
Correction of an overbite typically involves orthodontic treatment, with the specific approach depending on the severity and underlying cause. Traditional braces, consisting of metal or ceramic brackets and wires, are a common and effective method to gradually move teeth into their proper alignment. Clear aligners, such as Invisalign, offer a more discreet alternative, using a series of custom-made, removable plastic trays to shift teeth over time. These aligners apply gentle pressure to guide teeth into the desired position, with treatment duration varying based on the overbite’s complexity.
For growing children and adolescents, functional appliances may be used to guide jaw growth and correct skeletal discrepancies. These devices, like Herbst or Twin Block appliances, leverage the child’s natural development to influence the position of the upper and lower jaws, potentially reducing the need for more complex treatments later. Early diagnosis and intervention by an orthodontist are highly beneficial, as addressing an overbite while the jaws are still developing can lead to simpler, more effective, and less invasive treatment outcomes.
In severe cases, particularly those involving significant skeletal discrepancies or when jaw growth is complete, orthognathic (jaw) surgery may be recommended. This surgical procedure repositions the jawbones to achieve proper alignment, often performed in conjunction with orthodontic treatment. Jaw surgery can address imbalances in jaw size and position that braces alone cannot fully correct, leading to improved function and facial aesthetics.