Dental Materials Demystified: All-Ceramic Options for Multi-Unit Dental Bridges

Wednesday, August 28, 2013
Dental Materials Demystified: All-Ceramic Options for Multi-Unit Dental Bridges

A Ziemek Laboratories CAD technician designs a 3 unit e.max Press-to-zirconia framework and overlay.

Communication between the dental lab and the dental practice is one of my favorite topics.

It is a crucial element of a successful relationship between the lab and clinic. When communication is consistent and effective both businesses reap the rewards, experience less work stress, and grow.

A lab technician answering questions from dentists is a big part of successfully communicating, and subsequently this communication is a large part of my day-to-day.

In this article I share my answer to a common question I receive at the lab.

What are my all-ceramic material options in the posterior and anterior for multiple unit applications?

This is the question I am asked most frequently, and it is important for clinicians to understand the indications and contraindications of the most common all-ceramic materials on the market today. Dentists restoring multiple missing teeth want the best combination of esthetics and durability in an all-ceramic bridge, but they often are unsure of what material to prescribe.

In this situation I often recommend a combination of two ceramics with IPS e.max Press and zirconia as my all-ceramic materials of choice. These materials happen to be the two most popular all-ceramic materials we work with at Ziemek Laboratories today. When it comes to fabricating an all-ceramic bridge, the decision to combine both is a simple one because it allows us to use the best properties of both.

e.max Press provides the lab technician more choices for levels of translucency and opacity than zirconia, but zirconia is considerably stronger (e.max Press = 400 Mpa while monolithic zirconia = 1000-1400 Mpa). It also is important to note that Ivoclar Vivadent does not indicate e.max Press for multi-unit restorations longer than 3-units, and even those bridges are only indicated up to the 2nd premolar as the terminal abutment. If you have a posterior bridge including a molar prescribed, e.max Press is not a possibility. In fact, e.max Press is not indicated for cantilevers, extension units, Maryland bridges, or inlay-retained bridges.

The other factor you need to consider when looking at e.max Press for a bridge restoration is the maximum span of the pontic, which is different in the posterior and anterior. In the anterior the maximum indicated pontic width pre-op is 11 mm and in the posterior it’s 9 mm.

So after reading the indications and contraindications of e.max Press, one could assume that we never use it in larger multi-unit cases, but this is not the case. In fact we are using e.max Press on 6 and 8 unit anterior/posterior bridge cases, cantilevers, Maryland bridges and more at our lab with increasing frequency and with amazing results.

What’s our secret? We are pressing the e.max over zirconia frameworks. This solution provides a super strong and solid foundation with a highly esthetic overlay and a very strong bond between the lithium disilicate on the outside and the zirconia framework.

We fabricate multi-unit bridge restorations in full-contour zirconia quite often as well. Full-contour zirconia is not quite as translucent or natural in appearance as e.max Press or other layered ceramic alternatives, but it is incredibly strong, and the companies that manufacture zirconia are constantly evolving and refining their products, yielding increasingly better esthetic results. A full zirconia multi-unit case is also less expensive for us to produce than the layered alternative, and therefore we charge our dental clients less for them. Full zirconia multi-unit restorations lend themselves very well to posterior applications where strength takes priority over esthetics.

So there are options when it comes to fabricating all-ceramic bridges, and the material or materials of choice depends on the location and length of the bridge and the balance of esthetics and strength required for the case. A lab technician who is proficient with the latest products and materials can help their dental clients make well informed decisions for their patients.

  • <<
  • >>

Comments

-->