Today, the vast majority of posterior crowns fabricated in the United States by major laboratories are composed of fully-milled zirconia. This staggering shift in materials is trumped only by the fact that research shows there is a much better method of finishing zirconia surfaces. Since early 2014, when we hosted Rella Christensen RDH, PhD, to discuss wearability studies on monolithic zirconia, there has been revealing evidence that highly-polished zirconia is far superior to a glazed surface. Polished zirconia is so smooth that one is challenged to even pick up a crown without gloves. And, unlike glaze, this glassy, hygienic surface prevents plaque, rendering it much more biologically friendly.
Studies have shown polished zirconia surfaces are also kinder to opposing dentition than abrasive, glazed surfaces. And, once the glaze is worn, exposed rough zirconia is even more unkind to opposing teeth. Polished crowns, according to TRAC Research, retain their polished state as natural wear occurs. Polished also exhibits improved translucency and esthetics, as the transmission of light is unobscured.
Today, all ROE monolithic TLZ crowns are polished. We are excited to be leading the way with this improved modality. We know you will notice the difference on your next TLZ case.