Dental crowns are custom-made caps placed over a damaged or weakened tooth to restore its shape, strength, and appearance. They become the tooth’s new outer surface, protecting the remaining natural structure from further damage. When selecting a crown, the choice of material is a primary decision that impacts function and longevity. The two most common and time-tested materials used for permanent restorations are gold alloys and porcelain, each offering distinct advantages based on a patient’s specific needs. This comparison explores the functional and visual trade-offs between these two materials to help inform that decision.
Aesthetics and Visual Integration
Porcelain and ceramic crowns are widely favored for their ability to blend seamlessly with surrounding teeth. These materials can be precisely color-matched to the natural enamel, offering a translucent quality that mimics the way light interacts with a healthy tooth. Because of this superior cosmetic appearance, all-porcelain crowns are the standard choice for highly visible anterior (front) teeth.
A common compromise is the Porcelain Fused to Metal (PFM) crown, which uses a metal substructure for strength coated with tooth-colored porcelain. While stronger than all-porcelain, a PFM crown can sometimes reveal a thin, gray or dark line at the gum line if the gum tissue recedes. Gold alloy crowns, by contrast, are highly visible due to their metallic color, making them generally unsuitable for any tooth that shows when smiling or speaking. However, the polished, uniform surface of a gold crown is smooth.
Durability, Wear, and Longevity
The physical performance of gold and porcelain materials under the extreme forces of chewing presents the most significant difference between the two. Gold alloy crowns are recognized for their exceptional durability and function, often lasting for several decades. This longevity is due to gold’s slight malleability, which allows it to flex under heavy biting pressure without fracturing.
Gold’s mechanical properties also make it gentle on the opposing natural teeth. Gold wears at a rate almost identical to natural tooth enamel, preventing excessive abrasion of the tooth it bites against. Porcelain and ceramic materials, while hard, are more brittle and susceptible to chipping or fracture under concentrated stress, particularly in patients who grind their teeth (bruxism).
The hardness of many ceramic materials means they can be highly abrasive, causing accelerated wear on the enamel of the opposing tooth. If a ceramic crown is placed on a lower molar, the upper molar it occludes with may wear down prematurely. Gold’s ability to resist chipping and its enamel-like wear pattern often make it the choice for molars subject to the heaviest bite forces.
Procedural Differences and Cost
The preparation required for a crown differs significantly depending on the material chosen for the restoration. Gold alloy crowns can be cast into thin, strong layers, requiring the dentist to remove less of the natural tooth structure during preparation. This preservation of healthy tooth material is a major advantage for the long-term health of the tooth.
Porcelain and all-ceramic crowns require more aggressive tooth reduction to ensure the material is thick enough to withstand chewing forces without fracturing. Gold crowns are typically seated using conventional cementation, a straightforward process. Ceramic crowns, particularly modern high-strength materials, often rely on adhesive bonding techniques, which can be more technique-sensitive and complex to execute.
Cost Comparison
The initial financial outlay for these crowns can vary widely based on location and the specific alloy or ceramic used. Gold crowns can be expensive due to the fluctuating market price of the metal, often ranging from $800 to $2,500 per tooth. Porcelain and ceramic crowns may have a similar or slightly higher range, from $800 to $3,000, driven by the laboratory and milling fees required to produce a highly aesthetic, custom-shaded restoration.
Determining the Ideal Crown Material
The decision between a gold alloy and a porcelain crown relies on balancing cosmetic goals with functional requirements. For teeth in the anterior region that are highly visible, porcelain or all-ceramic crowns are selected almost exclusively because of their ability to mimic natural enamel. In these areas, the priority is aesthetics, and the biting forces are generally lower.
For posterior teeth, particularly the back molars that absorb the brunt of chewing force, gold alloy remains a highly effective choice. It is recommended for patients with strong bites, limited space between the upper and lower teeth, or a history of teeth grinding. The superior strength, flexibility, and minimal wear on opposing teeth make gold a practical selection where function and durability outweigh cosmetic considerations.