IPS e.max® ZirCAD MT Multi is the go-to zirconia material for dental cases that require high strength, but cannot be substantially compromisd in esthetics. In this blog, a dentist and lab technician relate their perspectives using IPS e.max ZirCAD MT Multi for a case involving severely worn teeth.
The unique formulation of the IPS e.max ZirCAD MT Multi discs offers biocompatibility and flexibility. The pre-shaded medium translucency (MT) multi zirconia oxide was designed to be the ideal material choice for cases in which high mechanical stability and natural looking dentition are most critical. The results are restorations that demonstrate a natural progression of chroma and translucency from dentin to enamel with no further characterization required. These qualities are what drew Dr. Randy Thivierage and his lab technician Doug Frye to rely on IPS e.max ZirCAD MT Multi for their case.
IPS e.max ZirCAD Case Perspective: Dr. Randy Thivierge
Throughout the twelve years that my patient, Chris, was treated at my practice, we discussed the worn condition of his teeth many times. Chris used occlusal guards for multiple years to try to slow the progression of wear. While this helped to some degree, it really wasn't enough.
In this past year, Chris was able to consider a restorative option. His primary concern was the potential loss of function should his teeth continue to wear. He admitted he would catch himself grinding his teeth and that it actually gave him some sense of satisfaction to do it.
While discussing possible treatment, I made sure he understood that the changes we would be making were designed to reduce his ability to grind his back teeth. Once he understood and accepted that as one of the treatment goals, we got initial records and planned the case.
Our primary goal was continued comfortable function. The existing conditions that conflicted with that goal were severely worn teeth, chipped teeth, a bruxing habit and lack of any anterior disclusion. Chris had no concerns with esthetics or pain.
I wanted to create a simple mechanical structure that would minimize and manage the forces destroying his natural teeth. After waxing up the case, I determined I could achieve Chris' goals by restoring the upper arch with crowns and the lower arch with composite in the posterior to protect the areas of exposed dentin. I could place crowns on the anterior to create the desired anterior disclusion.
One important consideration was the force Chris could generate even without posterior contacts. The incisal edges of all the anterior teeth needed to be designed to withstand those forces. This was accomplished by designing broad contacting surfaces with defined leading and trailing edges to reduce the likelihood of porcelain fracture, as well as utilizing IPS e.max ZirCAD for additional strength and durability.
The entire case was waxed up to determine how much vertical opening would be needed and to plan the excursive contacts. Because esthetics was a secondary concern, I left posterior margins very supragingival. The proposed shade of the restorations was lighter than the existing teeth. The color difference is easily seen in the final photos but was not a concern for the patient.
IPS e.max ZirCAD Case Perspective: Doug Frye, CDT, DTG
Upon receiving Dr. Thivierge’s case, I determined it was a type of occlusion I had not seen before. The theory behind it makes sense, in that the posterior teeth would be in disclusion in lateral and protrusive movements. The maxillary and mandibular anteriors carry the brunt of the occlusal forces.
The material used for this case had to consider strength without ignoring cosmetics. Rather than using traditional high translucent zirconia, which typically has a flexural strength around 600 MPa, I suggested a new product on the market that provides a gradient of esthetic shades and has a biaxial flexural strength of 850 MPa. IPS e.max ZirCAD MT Multi A3 was my choice for an optimum material.
The restorations were milled out without any need for pre-sintering stain liquids due to the gradient shaded MT Multi A3 puck. A small amount of post-staining was used to mimic the slightest of characterization found in patients with an A3 shade.
Pre-op photos were not provided for ideal shade match because the patient wanted to lighten his overall smile. The anteriors were designed to uphold the strength needed for this type of occlusion. Symmetric margin integrity and the translucency of the IPS e.max ZirCAD MT Multi resulted in a very good outcome.
What types of cases do you think would benefit from the strength and esthetics of IPS e.max ZirCAD?
BONUS VIDEO: Tech tip on how to optimize the new IPS e.max ZirCAD MT Multi Zirconia