An overbite, or deep bite, is a form of malocclusion where the upper front teeth significantly overlap the lower front teeth when the mouth is closed. While common, an excessive overlap causes functional and aesthetic problems. Dentures are prosthetic replacements for missing teeth and cannot physically change the underlying skeletal structure of the jaw. However, they are the primary method used to restore a functional bite and improve facial appearance for individuals who have lost all their natural teeth. Dental professionals correct the appearance and function of an overbite by carefully designing the new prosthetic teeth.
How Overbite Affects Denture Function
An existing overbite complicates the process of creating stable, functional dentures because it introduces an improper relationship between the upper and lower jaws. Excessive overlap causes the posterior (back) teeth to fail to meet correctly during chewing. This misalignment significantly reduces chewing efficiency, making it difficult to properly break down food.
The uneven distribution of force from a misaligned bite places excessive pressure on the underlying gum ridges. This accelerates jawbone shrinkage, known as resorption, leading to poorly fitting dentures over time. A severe overbite also increases the likelihood of dentures becoming unstable and dislodging during speaking or eating, which can cause clicking sounds and chronic gum soreness.
Designing Dentures for Vertical Correction
The process of correcting an overbite begins with establishing the correct vertical dimension of occlusion (VDO). The VDO is the precise measurement of the face’s height when the upper and lower teeth are in maximum contact, a dimension often lost when all natural teeth are removed. Restoring the ideal VDO is paramount, as it sets the blueprint for the entire bite correction.
Dental professionals use various methods, such as phonetic tests where the patient repeats specific “s” or “m” sounds, and the physiological rest position of the jaw to determine the correct VDO. Once this measurement is secured, the laboratory phase focuses on setting the prosthetic teeth in a specific relationship called centric relation. Centric relation is a repeatable, stable jaw position that ensures the joints and muscles are relaxed when the teeth come together.
Before the final dentures are made, the prosthetic teeth are set into wax rims for multiple try-in appointments. This try-in allows the dental professional to model the overbite correction and adjust the angulation and position of the teeth to ensure an aesthetic and functional bite. The wax rims are carefully manipulated to establish the proper vertical and horizontal overlap, ensuring the back teeth meet correctly before the denture is processed into its final acrylic form.
Stability Requirements for Severe Overbites
The severity of the original malocclusion dictates the type of prosthetic support needed to maintain the new, corrected bite. Conventional dentures rely solely on suction and the underlying gum ridge for retention, which is often inadequate when significant bite correction is performed. The forces generated by correcting a severe overbite can cause traditional dentures to shift, undermining the stability of the new VDO.
For patients with a pronounced overbite, implant-supported overdentures offer a superior solution for long-term stability. Dental implants are small titanium posts surgically placed into the jawbone that act as anchors for the prosthesis. This mechanical attachment provides greater retention than suction alone, preventing the denture from rocking or shifting under chewing forces. This stability is important for maintaining the corrected vertical dimension and preventing the appliance from dislodging.
Final Adjustments and Achieving the Ideal Bite
Once the finished dentures are delivered, the final stage involves chairside adjustments to refine the bite and ensure patient comfort. Due to minor changes during laboratory processing of the acrylic, the bite is rarely perfect upon first insertion. The dental professional uses articulating paper, which leaves colored marks on the prosthetic teeth, to identify high spots that interfere with a smooth and even closure.
These interferences are meticulously removed through selective grinding, a process that subtly reshapes the chewing surfaces of the teeth to achieve balanced contact. Multiple adjustment appointments are necessary for successful overbite correction. The patient’s feedback on comfort, chewing ability, and speech guides these fine-tuning sessions, ensuring the jaw muscles and joints adapt favorably to the newly established bite relationship.