December 14, 2017

Zirconia: Do you need to choose between strength and aesthetics?

White Paper - Paul Cascone, BE MetE, MS

When full contour zirconia entered the dental marketplace its primary benefit was strength. The advertisements made it appear as though the material was unbreakable.  After several years of clinical experience we now know that this impression is not true. However, the frequency of fractures was low and full contour high translucency zirconia rapidly became the dental restorative material of choice. 

The introduction of super translucent zirconia was heralded as an aesthetic alternative to IPS e.max®. While the material attained some market share, the growth was hampered by the material’s low strength. Some clinicians reported a higher fracture rate with this type of zirconia and it became apparent that not all zirconia types were the same. 

Unlike alloys that are classified as High Noble, Noble or Predominately Base, zirconia has no formal classifications. Also, unlike alloys, zirconia can be unforgiving to an insertion error because it does not flex. Applying pressure at a slight angle offset from the proper insertion angle will result in the zirconia unit fracturing. Similar PFM restorations would seat without difficulty because of the alloy’s elasticity. 

Read the full white paper by clicking here