Dental veneers are thin, custom-made shells, typically crafted from porcelain or composite resin, that a dentist bonds to the front surface of a tooth to improve its appearance. They are highly effective for correcting issues like discoloration, minor misalignment, or chips. Despite the protective layer a veneer offers, the natural tooth structure underneath remains susceptible to dental caries. The answer to whether a tooth can decay under a veneer is definitively yes, although the risk is generally low when the procedure is performed correctly and maintained properly.
The Mechanism of Decay Under Veneers
Decay beneath a veneer occurs when bacteria infiltrate the microscopic space between the veneer and the tooth structure. This infiltration is primarily due to the integrity of the adhesive seal breaking down, a process known as microleakage. The veneer itself does not decay, but the natural enamel and dentin underneath remain vulnerable to acid attack.
The bond relies on a strong dental cement that seals the two surfaces completely. If this bond is compromised—due to trauma, clenching, or poor initial bonding—a microscopic gap forms, most often at the veneer’s margins near the gum line or between the teeth. This tiny channel allows bacteria, sugars, and acids to seep beneath the veneer.
Once bacteria are trapped, they rapidly consume sugars and produce acid, which demineralizes the tooth structure. Since the decay is hidden from view by the opaque veneer, it can progress quickly, often affecting the underlying dentin. Decay can also begin on exposed parts of the tooth, such as the back surface, and then spread toward the bonded area.
Recognizing the Symptoms
Detecting decay beneath a veneer is challenging because the material obscures visual signs of a cavity. Patients should monitor for increased or sudden sensitivity, particularly when consuming hot or cold foods and beverages, which signals that the decay may have advanced deep enough to irritate the pulp or nerve tissue.
Discoloration is another common indicator, presenting as the veneer or underlying tooth structure darkening or appearing shadowed, especially along the gum line. Localized pain or a persistent toothache, particularly when biting down, can also suggest a problem. Swollen, inflamed, or receding gums around the veneered tooth may expose the vulnerable margin, indicating bacterial accumulation and potential decay.
Prevention and Maintenance
Preventing decay requires a stringent oral hygiene routine focused on preserving the seal and cleaning the vulnerable margins of the veneer. Brushing twice daily with a soft-bristled toothbrush and non-abrasive toothpaste removes plaque effectively without damaging the veneer surface. It is especially important to gently clean the area where the veneer meets the gum tissue, as this margin is a frequent point of decay initiation.
Daily flossing is paramount, as veneers typically do not cover the sides of the tooth where they contact adjacent teeth. Patients should thread the floss carefully and use a gentle, C-shaped motion to clean the exposed enamel and the margins of the veneer without snapping the floss. Limiting the intake of highly acidic foods and drinks, such as citrus and sodas, helps maintain the integrity of the bonding agent.
Regular dental checkups, usually every six months, are necessary for early detection. During these visits, the dentist examines the veneer margins for signs of microleakage and checks the surrounding gum tissue. Dental X-rays are also used to view the tooth structure beneath the veneer, allowing the dentist to detect decay that is not yet visible.
Addressing Decay: Treatment Options
Once a dentist confirms decay under a veneer, treatment focuses on removing the lesion and restoring the tooth’s health. For minor decay localized at the edge, a dentist may sometimes access and treat the cavity by drilling from the back side of the tooth, potentially preserving the veneer. However, in most instances, the veneer must be removed entirely to access the decay and ensure all infected tooth structure is eliminated.
After the veneer is detached, the dentist excavates the decay and prepares the remaining healthy tooth structure. If the decay is shallow, the tooth is restored with a dental filling material. If the decay has resulted in significant loss of structure, the tooth may require a full-coverage crown for support before a new restoration is placed. If the decay has reached the dental pulp, a root canal procedure may be necessary to save the tooth. Following restoration, a new custom-made veneer is bonded into place.