I recently spoke with Rudy Ramirez, director of PFM (Porcelain Fused to Metal) at Glidewell Laboratories. With over 30 years of experience in the dental laboratory industry, he has a wealth of knowledge about the evolution and current status of PFM crowns and bridges, which still make up the majority of crowns and bridges in the field. Rudy’s department is larger than most labs, so he sees a broad cross-section of dentistry. The following are excerpts from our conversation.
M:Some speakers on the lecture circuit predict the end of the use metal in mouth. Worried about PFMs disappearing?
Q: No, at least not in the short term. For years, every new all-ceramic system predicted that it was going to replace PFMs. While these all-ceramic systems enjoy a period of success when everyone jumps on board at first, dentists eventually begin to experience technical problems and see failures. A lot goes back to the tried and true PFM. Today, we are seeing PFMs go through the roof in terms of acceptance. For example, Captek offers biocompatibility that others do not.
M:Among the crowns manufactured at Glidewell, what percentage are PFMs?
Q: About 80 percent. There is a lot of buzz around all-ceramics. A lot of people are talking about them. But the reality is that today you cannot find an economical all-ceramic. Dentists we speak to express their concerns about price pressure. They don’t ask what is the best all-ceramic to use. There must be a solution. That’s why we’re developing the Newport system, which uses pressed-on-metal technology. We believe in providing high quality, stable restorations at an affordable price. The issue of price prohibits some people from seeking dental care.
M:I found out about Captek because I was looking for the most aesthetically pleasing PFM I could find. Although I feel comfortable using all-ceramic restorations in some cases, such as veneers for full coverage restorations, I still want the confidence that PFMs provide. Tell us more about your experiences with the product.
Q: When I started with Captek about 14 years ago, the product had a humble beginning. It was considered a “boutique” product for individual anterior restorations only. Working with company executives, we brought the product into the mainstream. We wanted to show what he could do everywhere. Today, we use Captek for single units, bridges and large cases. It is the most prescribed brand of crown we carry at Glidewell.
M:In terms of PFMs in general, what are the biggest problems you face when dentists send cases?
Q: Common problems include inadequate closure and poor impressions. These problems are no different than what you would have with all-ceramics. A unique problem is that doctors do not seem to have a good grasp of technology. Their expectations are unrealistic. Many seem to think that once you prescribe a PFM, there are no more rules.
M:What major advances do you see in the future?
Q: Metal pressing and automation. NetPress will be a major advance in terms of consistency and economy. It involves a different way of making a crown. While still a PFM, its manufacturing process is much more predictable. It is easier to train technicians using this method compared to traditional methods. Also, the anatomy is more consistent. I recently had a doctor tour the lab. He saw the NetPress process and how consistent the anatomy was from crown to crown.
M:Would it be easier for technicians to make esthetic PFM restorations if more dentists provided digital photos?
Q: Absolutely. These photos are of limited use in terms of shadow, but are great for showing the mouth. We can use digital photos to see if we have achieved what the dentist is aiming for. But dentists need to be careful. Intraoral images can cause problems. Doctors can e-mail digital photos to [email protected].
M:Speaking of shading, I rely more on digital shadow capture systems. What is the lab’s view?
Q: Digital shade capture systems are a definite help in the lab. We use Vita Easyshade for QC on our restorations before. Then we use stain and glaze. Doctors using the Vita have less shadow remakes. It’s not that these systems are always the best approach, but they are often better than relying on the human eye. From time to time, we have cases where a doctor requests a completely different shade than he originally requested. The context may have been wrong or the hue may have been misinterpreted. Digital systems remove the human factor. You just shoot a tooth and the system tells you the shade.
Dr. Michael DiTolla is Director of Clinical Research and Education at Glidewell Laboratories in Newport Beach, California. He lectures nationally on both restorative and cosmetic dentistry. He also teaches hands-on digital photography and digital image processing classes for the whole group. Dr. DiTolla has several clinical programs available on DVD through Glidewell. For more information about this article or for more information about by receiving a free copy of one of Dr.’s clinical DVDs. DiTolla, e-mail him at [email protected]or call (888) 535-1289.
