For many years, porcelain-fused-to-metal crowns have been a go-to solution for full-coverage restorations. Their reliability has been proven through extensive long-term clinical research that is well documented in the dental literature.
Millions of porcelain restorations have been placed worldwide. The real reason they became so popular has to do with their strength and their ability to offer an aesthetic solution for teeth in all areas of the mouth. Porcelain-fused-to-metal crowns often last 15 to 20 years before requiring replacement in patients with good oral hygiene.
Read on to learn about porcelain-fused-to-metal crowns and when it is a useful dental solution from the team at Stomadent Dental Laboratory.
When To Use Porcelain-Fused-to-Metal (PFM) Crowns
Although other crown materials, such as lithium disilicate (Emax) and zirconia, have made great strides in recent years, porcelain-fused-to-metal crowns continue to have value as a restorative solution in a number of specific situations:
- Patients with hard bites or bruxism can benefit from an indestructible metal occlusal surface that doesn’t wear the opposing dentition
- Metal rests and lingual surfaces can be made to accept cast metal removable partial dentures
- Precision attachments for clasp-free cast metal removable partials
Material Properties
Depending on the dentist’s selection, porcelain is applied to a metal substructure made from high-noble, semi-precious metals, or base metal alloys. Substructures made from alloys that contain higher percentages of noble metals offer greater material strength and are known for being more biocompatible when it comes to metal allergies and reactions. Differences in alloy composition often determine the cost of the final restoration.
- High-noble: 60% noble metals, including a combination of gold, platinum, or palladium with a minimum of 40% gold content.
- Semi-precious or noble: 25% or more gold or other noble metals supplemented with other metal elements.
- Non-precious or base metal: Less than 25% noble metal content combined with chromium beryllium, nickel, and cobalt. Additional elements may include tungsten, manganese, iron, silicon, carbon, and molybdenum.
| USES |
|---|
| Full-coverage crowns |
| Bridges |
| Long-span bridges |
| ¾ crowns |
| Crowns and bridges with metal occlusal surfaces |
Taking Impressions for Porcelain-Fused-to-Metal Crowns
Although polyvinyl siloxane impressions have been successfully used for many years, there are now more accurate methods to capture an exact representation of a PFM crown prep.
Impressions for porcelain-fused-to-metal crowns taken via chairside 3D scanning technology offer many distinct benefits and advantages over physical impressions.
Color Choices
While porcelain colors correspond to the VITA Shade Guide, a skilled ceramist has the ability to combine more than one color on the same restoration, if necessary, to give the crown a true blended appearance with the neighboring teeth. In addition, custom staining is also possible for an enhanced, more lifelike appearance even after final crown fabrication.
Delivery and Cementation
Properly reduced PFM crown preps allow for partial mechanical retention. This lets the cement, the weakest link, be applied in a thin layer for security rather than relying upon a bulk amount of cement material to take up excess space inside of the crown. Most dentists find resin-modified glass ionomer works well for PFM crown cementation.
Adjustments
If digital impressions were used to capture the PFM crown prep, few to no adjustments are necessary upon delivery. This saves a tremendous amount of time and reduces overall costs to the dental practice.
Porcelain-Fused-to-Metal Crowns: A Sound Choice
Not sure that porcelain fused to metal will give your patient the result they are looking for? Stomadent Dental Laboratory offers fixed restorative solutions to address every need and every aesthetic concern. No crown material fulfills every need.
Each type of restorative material has its own set of advantages and disadvantages. Our experienced and knowledgeable dental lab technicians can direct you to the most appropriate restoration for your specific clinical indication.
Why You Can Trust Us
Stomadent Dental Laboratory is a certified provider of PFM products. We use genuine materials and techniques mandated by each respective manufacturer to ensure long-lasting, predictable results. Stomadent technicians stay abreast of changing techniques through ongoing training and education required to maintain these certifications.
Our lab products are made in the USA