PFM Crowns: Understanding to choose the best fit

If zirconia crowns have been the preferred restorative solution recently, PFM crowns (Porcelain-Fused-to-Metal) have remained a staple in restorative dentistry for decades. PFM crowns are a traditional prosthetic option praised for their durability and the natural aesthetics provided by the porcelain overlay. They remain a primary choice for patients, prioritizing strength and functionality over aesthetics. 

This article provides an in-depth overview of the advantages and disadvantages of PFM crowns, assisting dentists in selecting the most suitable option for their patients.

What is a PFM Crown?

Porcelain-fused-to-metal (PFM) crowns are dental prosthetics composed of a metal substructure fused with an outer layer of porcelain. The metal framework ensures exceptional resistance to occlusal forces, making PFM crowns highly durable and suitable for posterior restorations, although they can also be used for anterior teeth.

An overview of PFM crown

The materials used in producing PFM crowns vary based on the preciousness of the metal content.

• High-noble: It has at least 60% noble metals, such as platinum, palladium, or gold. This type offers superior biocompatibility, strength, and corrosion resistance but comes with a higher cost due to its precious metal composition.

PFM high-noble

• Semi-precious: Semi-precious is composed of at least 25% noble metals, often combined with elements like zinc, tin, cobalt, or gallium. It provides a balance between cost-effectiveness and durability, maintaining good mechanical and aesthetic properties.

PFM semi-precious

• Non-precious: Non-precious contains less than 25% noble metals, typically incorporating chromium, nickel, or beryllium. Although reasonably priced, base metal alloys may have lower biocompatibility and pose risks of allergic reactions in some patients.

PFM non-precious

Advantages

In terms of safety and reliability, PFM crowns are recognized globally, and millions of successful cases are performed worldwide.

• Strong and versatile: PFM crowns are highly durable and suitable for all areas of the mouth. They are particularly ideal for posterior restorations, where chewing forces are significant.
• Long-lasting: According to several studies, PFM crowns have a relatively long lifespan (from 10 to 15 years) and are resistant to corrosion. The lifespan of PFM crowns often depends on factors such as oral hygiene and bite force.
• Aesthetic: PFM crowns offer high aesthetics, especially in the first few years of use. The metal ring at the bottom of the crown can be seen through the gum, so this type of crown is often used for molars.
• Cost-effective: PFM restorations are generally more affordable than zirconia or all-ceramic crowns.

Disadvantages

Despite having many outstanding advantages, PFM crowns still have certain drawbacks that are hard to overcome. Due to the metal core structure, an opaque layer is applied to cover it; however, the metal may still be slightly visible, lacking translucency and a natural appearance. In cases of gum recession, the dark metal margin can become exposed, compromising aesthetics.

While the metal framework is sturdy and durable, the porcelain layer on the outside can chip or crack due to its lower strength, especially in patients with bruxism. The porcelain layer may cause slight wear on the natural teeth of the opposing arch, particularly if the surface is not polished thoroughly. It is not suitable for individuals with metal allergies.

PFM vs. other materials

PFM vs. Zirconia

When directly comparing durability, Zirconia crowns offer greater hardness and wear resistance, making them suitable for both posterior and anterior teeth. In terms of aesthetics, Zirconia crowns also outperform PFM crowns as they lack a metal margin. However, PFM crowns remain a more cost-effective option in many cases since Zirconia is more expensive.

PFM vs. Zirconia

PFM vs. Full-Cast Metal

Full-cast metal crowns are more durable, particularly for cases involving heavy chewing forces. However, their aesthetics are limited as they lack a porcelain layer and are entirely metallic in color. As a result, Full-Cast Metal crowns are often preferred for posterior teeth that are less visible or for patients prioritizing durability over aesthetics.

PFM vs. Full-Cast Metal

PFM vs. E.max

E.max crowns exhibit superior translucency and light-reflecting properties, offering a more natural appearance compared to PFM crowns. It makes the production process for E.max crowns more complex, and the cost is significantly higher than PFM crowns. However, E.max crowns are less durable than PFM crowns, especially for posterior teeth subjected to heavy chewing forces.

PFM vs. E.max

Choosing the right restoration type depends on the patient’s needs and condition, but durability and suitability for personalized cases must always be ensured.

Conclusion

PFM crowns remain a reliable choice in restorative dentistry due to their perfect balance of durability, aesthetics, and cost-effectiveness. Despite certain limitations, PFM crowns are still an optimal choice for various clinical cases. To achieve optimal restorative outcomes, dentists should carefully consider the specific needs of patients.

VTS Dental Lab provides a wide range of high-quality restorations tailored to individual cases. For more information, please contact our office now.