Nanostructured materials were designed to produce high‐strength porous Y‐TZP ceramics. Materials were prepared using homoaggregation resulting in a homogeneous distribution of nanosized particles attached to the surface of submicrometer‐sized particles. After slip casting, green pellets were biscuit sintered at various temperatures in an ambient air atmosphere. The flexural strength of nanostructured ceramics substantially increased from 190 to 430 MPa in a narrow density range between 58% and 60% of theoretical density. This value is approximately two times higher than that obtained with dry‐pressed biscuit‐sintered Y‐TZP ceramics exhibiting similar fractional density.

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Moderately porous Y-TZP dental ceramics were designed to combine the high strength and fracture toughness of densely sintered Y-TZP and the relatively low elastic modulus of porous Y-TZP ceramics. The materials were produced by biscuit-sintering dry-pressed pellets at different temperatures in an ambient air atmosphere. The flexural strength progressively increased with the fractional density, starting from 150–200 MPa at 55–60 % of theoretical density (TD), and exceeding 500 MPa at >80 % TD. The elastic modulus of the early-stage sintered material was matched with that of dentine, but the flexural strength was too low for a practical application. Strength values equal to or higher than those of the existing dental glass-ceramics and glass-infiltrated ceramic materials were achieved with specimens sintered to 8085 % TD, but the elastic modulus of these ceramics (100130 GPa) was about two times higher than that of dentine. Soft grinding of the biscuit-sintered samples resulted in a noticeable increase in the surface roughness, also leading to a significant strength reduction.