Dental veneers are custom-made, thin shells, typically fashioned from porcelain or composite resin, that are bonded to the front surface of teeth to improve their appearance. While they are a highly effective cosmetic solution for issues like discoloration or minor misalignment, they cannot be placed over active dental decay. Any existing decay must be completely treated and resolved before a dentist can proceed with the veneer procedure.
Why Cavities Prevent Veneer Placement
Active dental decay, commonly known as a cavity, compromises the structural integrity of the tooth required for successful veneer placement. The bonding process relies on a strong, clean interface between the dental adhesive and the healthy enamel. Compromised tooth material does not provide a stable surface for the veneer to attach permanently.
Placing a veneer over an active cavity poses risks to the long-term health of the tooth. Decay is caused by acid-producing bacteria, and sealing this activity underneath an impermeable veneer allows the decay to progress rapidly and undetected. This trapped decay can quickly advance into the deeper dentin layer, potentially reaching the pulp and necessitating a root canal or extraction.
The materials used to bond the veneer, typically a resin cement, are formulated to adhere to healthy, acid-etched enamel. The required bond strength cannot be achieved when the underlying surface is soft, infected, or damaged by decay. Attempting to bond to decay results in premature failure, causing the veneer to debond or lift prematurely. A healthy tooth structure is mandatory for the longevity and stability of the restoration.
Treating Decay: The Necessary Pre-Veneer Steps
The presence of decay necessitates restorative dentistry before any cosmetic work can begin. The initial step involves the complete removal of all decayed enamel and dentin to eliminate the bacterial infection. This process is identical to treating any other cavity and ensures that the tooth is clean.
Once the decay is removed, the resulting void in the tooth structure must be filled and stabilized, most often using a composite resin restoration, or filling. This filling replaces the lost tooth material and restores the tooth to a healthy, solid foundation. The dentist must confirm that the size and position of the filling do not compromise the tooth’s overall strength or interfere with the final veneer placement.
If the decay is extensive, such as when it involves a significant portion of the tooth or has reached the nerve, a simple filling may be insufficient. The dentist might determine that a full crown or a root canal followed by a crown is necessary to fully restore the tooth. If a tooth requires a crown, it is no longer a candidate for a veneer, as a crown covers the entire tooth structure, not just the front surface.
Other Essential Dental Requirements for Veneers
Achieving a healthy foundation for veneers extends beyond addressing cavities; the entire oral environment must be stable. Periodontal health is a requirement, meaning the gums must be free of active disease such as gingivitis or periodontitis. Diseased gum tissues can compromise the margin where the veneer meets the tooth, leading to aesthetic issues and potential bond failure.
Another element is the presence of sufficient tooth enamel. The veneer procedure typically requires the removal of a minimal amount of enamel, often less than a millimeter, so the shell fits flush and looks natural. This remaining enamel is crucial because it provides the best surface for the dental cement to bond and achieve retention. Teeth with severely eroded or insufficient enamel may not be suitable candidates for veneers.
Bruxism and Grinding
Existing mechanical issues must also be resolved, particularly habits like bruxism, or chronic teeth grinding. The excessive forces generated by grinding can cause the porcelain material to chip, crack, or fracture prematurely. Patients with bruxism must often be fitted with a protective night guard to wear after veneer placement to mitigate these forces.
Misalignment and Bite Issues
Severe tooth misalignment or bite imbalances may require orthodontic treatment before veneers are considered. Veneers alone cannot correct major structural or functional problems.