A core build-up is a restorative dental procedure that replaces missing tooth structure to create a stable, prepared surface for a dental crown. This process rebuilds the tooth’s foundation, serving as a substructure that the final crown will fit over and attach securely. The goal is to transform a compromised tooth into a prepared shape that can retain a crown, ensuring the restoration’s long-term success. When a significant portion of the natural tooth is missing, the build-up provides the necessary strong anchor.
Why a Core Build-Up is Necessary
The primary reason a core build-up is performed is to provide sufficient structural integrity for the crown. Teeth damaged by large cavities, fractures, failed fillings, or extensive procedures like a root canal often lack the necessary bulk. Without adequate height and volume, a crown cannot be retained properly, increasing the risk of the restoration failing or fracturing prematurely.
The build-up ensures the remaining tooth structure meets specific mechanical requirements for durable crown placement. This includes establishing a proper taper and sufficient height, which contribute to the crown’s retention and resistance against dislodging forces. Dentists aim to create a strong, solid base that can withstand the biting and chewing forces placed upon the crown. The build-up transforms a weakened, irregularly shaped stump into a uniform, prepared surface ready for the final dental cap.
Step-by-Step Procedure Overview
The core build-up procedure typically begins with the administration of a local anesthetic, though this step may be omitted if the tooth is non-vital following a root canal. The dentist removes all remaining decay, compromised tooth material, and any old filling components. This preparation is crucial to ensure the new core material bonds effectively to a clean, healthy tooth surface.
Once the area is clean, a bonding agent is applied to the remaining tooth structure to enhance the adhesion of the build-up material. If minimal tooth structure remains, a small post or threaded pin may be cemented into the root canal space for additional mechanical retention. A matrix band or mold is often wrapped around the tooth to contain the flowable core material and shape it into a rough tooth form.
The core material is then applied into the prepared area, filling the voids and restoring the tooth’s volume. If a light-cured composite is used, the dentist exposes it to a curing light to harden it completely. The hardened material is then shaped and contoured with a dental drill to create the precise, tapered preparation needed to receive the crown. The patient will often receive a temporary crown immediately following the procedure while the permanent one is being fabricated.
Materials Used and Expected Outcome
The materials used for a core build-up are selected for their strength and compatibility with the tooth structure. The most common materials today are composite resins, which offer excellent mechanical properties and bond adhesively to the tooth. These composites are often dual-cure, meaning they can be hardened both by a curing light and through a chemical reaction.
Other options include glass ionomer cement or resin-modified glass ionomers, which release fluoride and bond well to dentin. While traditional amalgam was historically used, its popularity has declined due to its inability to bond adhesively. Dentists may choose a material based on its ability to mimic the elasticity of natural dentin, which helps distribute forces evenly and reduces the chance of fracture.
The immediate expected outcome of the core build-up is a structurally sound tooth preparation, which serves as a durable base for the final crown impression. Rebuilding the missing structure increases the longevity and stability of the entire restoration. This reinforced foundation protects the remaining natural tooth and ensures the crown remains secure and functional under normal chewing stresses for many years.