Glidewell Laboratories will cease production of its conventional feldspathic PFMs effectively on October 1. All future PFM cases prescribed from the lab after then will use the company’s Obsidian lithium silicate ceramic in place of feldspathic porcelain.
According to the company, Obsidian Pressed to Metal crowns and bridges represent a higher standard of care than conventional PFMs in ceramo-metal restorations. Obsidian lithium silicate ceramic exhibits more than 4 times the flexural strength and twice the chip resistance of traditional porcelains, Glidewell says.
Additionally, the company reports, the material polishes beautifully and is kinder to opposing dentition than previous PFM ceramics. Obsidian’s increased toughness makes it ideal for bridges, cases with insufficient vertical space for full-contour zirconia, and screw-retained restorations, Glidewell adds.
Furthermore, the company says that Obsidian’s greater translucency matches shades and blends more naturally with real dentition. Obsidian Pressed to Metal restorations also enable a new level of marginal precision, with tolerances as tight as 20 µm, Glidewell says.
Each metal understructure is digitally designed and then fabricated with a computer-controlled selective laser sintering machine, which uses a laser to bind metal powder into a 3-D shape. The precision established with these techniques helps prevent bacterial invasion and cement washout in delivered restorations, according to Glidewell.
Obsidian Pressed to Metal restorations are priced at the current PFM rate of $109 per unit for nonprecious alloy and at a reduced rate of $116 per unit for white noble alloy.