Items anybody associates with ceramics like bricks or plant pots are pretty fine after firing, without any glaze. Some parts depend on the lack of glaze to be useful. But
ceramics is a wide term, not just tableware or construction materials. You can find ceramics in brakes, bearings, engines and other parts that, while not will withstand hits, will suffer strong pressures, vibrations and heat. Ceramics in military are used to absorb lots of energy in impacts (personal and vehicle armor), but not break while wearing/driving around.
From their site "Lithoz enables the fabrication of prototypes without any costs for tools while achieving the mechanical characteristics of serially produced parts". They seem to target small parts for machinery and medical implants, so you would expect strong parts. Would you install a gear that breaks easily? Or a bone replacement?
Before discarding as fragile, get a sample.