Monday, February 25, 2013

Expanded Uses Of Zirconia

Due to its immense popularity and changing modalities, zirconia has been a frequent topic of discussion in our newsletters during the past few years. Another is progressive implant solutions. The first part of this section on zirconia will integrate the two topics, and the second will offer an alternative to metal-free bridges.

Part 1: Hybrid dentures have significantly increased in popularity. Although a wonderful option for the patient, they do present challenges, primarily with regard to strength and longevity. Fortunately, the technology with which they are produced continues to improve. Updates include virtually-designed milled bars, the use of special teeth, and required minimum vertical openings.

This year we are offering an exciting option to the traditional hybrid, a full-arch,


screw-retained, 100% zirconia bridge. This milled, monolithic bridge, which we call TLZ-IB, provides esthetics and durability with very little maintenance. The restoration is available for most implant systems and is attached to the implants via titanium interfaces that fit precisely into the bridge. As with all our implant-supported restorations, screws only contact titanium, and never zirconia.

Fabricating these cases differs slightly from traditional hybrids. The implant-level impression and bite registration are the same, but the try-in is unique. Once a set-up has been approved intra-orally, it is digitized and reproduced into a screw-retained, milled, acrylic prototype. This monochromatic appliance will be tried-in to confirm esthetics and function. The adjusted, patient-approved try-in is our blueprint for the final prosthesis that will require little-to-no adjustment.

Part 2: Monothltic zirconia, TLZ, is a great restorative option, and due to its superior strength has become many doctors’ “go-to material” for posterior crowns and bridges. In esthetically critical areas, PFZ restorations (porcelain-fused-to-zirconia) incorporate layered, veneering ceramics for a more vital appearance. Sometimes a case requires both the strength of monolithic zirconia and high esthetics. We can accomplish this with a hybrid restoration we call TLZ-cutback. We virtually design the monolithic material in functional areas, and digitally cut back labial material to make room for stacked porcelain to improve the vitality
of the case. If you have a patient that requires this combination, ask for a TLZ-cutback.

TLZ flexural strength comparison

TLZ flexural strength comparison
Popular materials compared to TLZ