A dental crown is a tooth-shaped cap designed to cover a damaged or weakened tooth, fitting over the entire visible portion. Its primary function is to restore the tooth’s original shape, size, and strength, while also improving its overall appearance. Dentists use crowns to prolong the life of a natural tooth by shielding it from further damage.
Reasons for a Dental Crown
Crowns are placed for various dental issues where a traditional filling might not be sufficient. One common reason is extensive tooth decay that has compromised a significant portion of the tooth structure. When a tooth is severely fractured or broken, a crown can restore its integrity and prevent further deterioration. Teeth with very large fillings, especially those that have weakened the tooth over time, often benefit from a crown to provide added protection.
Following root canal therapy, a tooth can become more brittle, and a crown is frequently recommended to strengthen it and seal it from bacteria. Crowns are also utilized for cosmetic enhancements, covering teeth that are severely discolored, misshapen, or poorly aligned to improve smile aesthetics. They can additionally serve as anchors for dental bridges or cover dental implants.
The Tooth Preparation Process
The process of preparing a tooth for a crown involves carefully reshaping it to create a stable foundation. Initially, the dentist removes any decayed or damaged areas from the tooth using a dental drill. To make space for the crown, a precise amount of the tooth’s natural enamel and sometimes dentin is removed from all surfaces.
The goal is to sculpt the tooth into a smaller, tapered or cylindrical “stump” or “core” that the crown will fit over securely. This shaping ensures the crown integrates properly with the patient’s bite and maintains aesthetic harmony with adjacent teeth. After reshaping, impressions of the prepared tooth are taken, either with putty-like material or digital scanners, to create a custom-made crown in a dental laboratory. While the permanent crown is being fabricated, a temporary crown is placed to protect the prepared tooth and maintain proper spacing.
Appearance of the Prepared Tooth
Once the natural tooth has been prepared for a crown, its appearance changes significantly. The tooth is reduced in height and width, forming a smaller, tapered or cylindrical shape. This precise shaping allows the final crown to fit over it without appearing bulky or unnatural.
The color of the prepared tooth can vary; it might be off-white or yellowish, reflecting the underlying dentin layer, which is naturally darker than enamel. If the tooth had significant decay or a large filling, the prepared surface might show darker areas or the color of restorative materials like amalgam or composite resin used to build up the tooth before shaping. The surface will feel rough or uneven to the tongue if exposed, lacking the smooth, glossy texture of intact enamel.
What to Expect if a Crown Detaches
If a dental crown detaches, the underlying prepared tooth will become visible. The patient will see the “stump,” which can appear smaller and differently shaped compared to natural teeth. The exposed tooth might also appear discolored, showing yellowish dentin or darker areas if there was decay or previous restorative material. The sensation of the exposed tooth can be one of sensitivity to temperature changes or pressure, as the protective enamel layer is no longer intact.
It is important to contact a dentist immediately if a crown comes loose or falls off. Until a dental appointment can be arranged, the crown should be carefully retrieved and kept safe. Temporary measures, such as avoiding chewing on the affected side of the mouth and using over-the-counter temporary dental cement to reattach the crown, can offer short-term relief. Prompt dental attention is advised to prevent further damage, decay, or infection to the exposed tooth.