An overbite, often referred to as a deep bite, is a common form of malocclusion where the upper front teeth vertically overlap the lower front teeth significantly. While a slight overlap of about 1 to 2 millimeters is considered normal, an excessive overlap—typically defined as more than 40% of the lower incisor being covered—can lead to various functional and structural problems. This misalignment places unnatural stress on the entire oral system, affecting daily functions and potentially causing long-term physical damage.
How Overbites Affect Everyday Functions
An excessive overbite impairs the efficiency of mastication, or the process of properly chewing food. The misalignment prevents the upper and lower teeth from meeting ideally, reducing the surface area available for grinding. This reduces the ability to thoroughly break down tougher foods, forcing the jaw muscles to work harder and potentially contributing to digestive issues.
The jaw muscles become strained due to the constant effort to compensate for the incorrect bite position during eating. Individuals may struggle to bite cleanly into certain foods, like apples or sandwiches, or they may develop habits like cheek or lip biting. This muscle tension can contribute to chronic discomfort and fatigue in the facial area.
Speech clarity depends on the precise relationship between the teeth, tongue, and palate for proper air flow and sound formation. An overbite can cause a lisp or a whistling sound, particularly when pronouncing sibilant sounds like “s” and “z.” This occurs because the tongue cannot achieve the correct placement against the palate or the back of the teeth. Correcting the bite often improves these articulation difficulties by allowing for proper tongue positioning.
Long-Term Damage to Teeth and Gums
The continuous, forceful contact between misaligned teeth results in accelerated tooth wear, known as attrition. The lower front teeth rub against the backs of the upper front teeth, leading to premature loss of enamel. As the protective enamel layer wears down, the underlying dentin may become exposed, causing increased sensitivity to hot and cold temperatures.
This excessive pressure can also cause the affected teeth to become susceptible to chipping, cracking, or fracturing over time. A deep overbite can be destructive to the gums and bone structure. In severe cases, the biting edges of the lower front teeth can repeatedly traumatize the palatal gum tissue behind the upper front teeth.
This chronic irritation and trauma can lead to inflammation, gum recession, and a stripping away of the soft tissue. Gum recession exposes the sensitive root surfaces of the teeth, heightening the risk of root decay and compromising the periodontal support system.
The Relationship to Jaw Joint Discomfort
The Temporomandibular Joints (TMJ) connect the lower jawbone to the skull and are responsible for all jaw movements. An overbite forces the lower jaw to function in a strained position, placing uneven pressure on the joint components. When the bite is misaligned, the jaw muscles must constantly compensate, which leads to chronic muscle tension and fatigue.
This persistent strain contributes to temporomandibular disorders (TMD). Symptoms often include tenderness or soreness in the jaw joint near the ears, along with clicking, popping, or grinding sounds when the mouth is opened or closed. The tension from overworked jaw muscles can also radiate outward, causing frequent tension headaches, earaches, and stiffness in the neck and shoulders.
The deep overbite may force the lower jaw into a position that compresses the joint, potentially leading to advanced joint erosion. Correcting the overbite helps to align the upper and lower jaws properly, which reduces stress on the joints and surrounding musculature. This alignment alleviates the chronic pain and discomfort associated with the forced compensation of the jaw system.