The term “buck teeth” refers clinically to an overjet, a malocclusion where the upper front teeth protrude horizontally beyond the lower front teeth. While often viewed as a purely cosmetic concern, an increased overjet can indicate an underlying issue with the alignment of the jaws or the positioning of the teeth.
Defining Overjet and Self-Assessment
Overjet is the horizontal distance between the upper and lower front teeth. For a well-aligned bite, this overlap usually measures between two and four millimeters (2–4 mm). An overjet is considered increased when this measurement exceeds 3.5 millimeters.
To perform a basic self-assessment, gently close the back teeth and measure the space between the front surfaces of the upper and lower teeth. If the upper front teeth extend noticeably past the lower teeth, particularly if the gap is greater than the width of a standard pencil eraser, it suggests an increased overjet. This condition is often classified as a Class II malocclusion, indicating a jaw discrepancy.
The development of an overjet is influenced by skeletal, dental, and environmental factors. Genetic predisposition plays a significant role, as jaw size and shape are often inherited. However, certain habits can also contribute to the protrusion of the upper teeth. Prolonged habits like thumb-sucking or the extended use of a pacifier past the age of four can push developing permanent upper teeth forward. Chronic tongue thrusting, where the tongue pushes against the back of the upper teeth during swallowing, is another behavioral cause.
Why Correction Matters: Functional and Health Impacts
An increased overjet can lead to several functional and health complications. One significant risk is increased susceptibility to dental trauma, particularly for the upper front teeth. Studies indicate that individuals with an overjet greater than four millimeters have a roughly doubled risk of suffering an injury, such as a fracture or chipping.
The misalignment can impede proper oral function, leading to difficulty chewing. When the upper and lower teeth do not meet correctly, the efficiency of biting and breaking down food is reduced. A large overjet may also make it challenging to achieve complete lip closure, resulting in a constantly dry mouth.
A dry oral environment reduces the protective effect of saliva, potentially increasing the risk of tooth decay and gum problems. Speech can also be affected, as the positioning of the front teeth is important for forming certain sounds, and some individuals may develop a lisp or other speech impediments. In severe cases (overjet greater than six millimeters), there is a negative impact on oral health-related quality of life, specifically affecting functional limitations.
Orthodontic Solutions for Alignment
Addressing an overjet involves orthodontic treatment tailored to the severity of the protrusion and the patient’s age. The most common treatments include traditional metal or ceramic braces, which use brackets and wires to gradually shift the teeth into alignment. Clear aligner systems are also effective for correcting mild to moderate overjets.
In growing children and adolescents, functional appliances, such as the Herbst appliance or Twin Block, may be used to guide the growth of the lower jaw forward. These devices capitalize on remaining growth potential to correct the skeletal discrepancy. This phase is often followed by fixed braces to perfect the alignment.
For severe overjets resulting from a significant skeletal discrepancy, a combination of orthodontics and orthognathic surgery may be necessary. The surgery involves repositioning the jaw bones to achieve a functional bite relationship. Following active treatment, a retainer is routinely used to hold the teeth in their new positions, ensuring long-term stability.