Fused deposition modeling shaping of glass infiltrated alumina for dental restoration

The work focuses on the 3D printing of glass infiltrated alumina ceramics. Thermoplastic filaments with different alumina loadings were extruded and used as intermediate precursors in fused deposition modeling (FDM). The green alumina samples were pre-sintered in air at 1150 degrees C and lanthanum-based glass frits were subsequently infiltrated into these preforms at 1120 degrees C. The frits were dispersed in water and applied as a slip on the surface of Al2O3 porous surface. During this thermal process the glass frits melts and diffuses from the surface to deep inside the alumina preform to form a composite. Mechanical properties are close to pure alumina sintered materials whereas good translucency also achieved. This energy efficient, cheap and low material waste process is convenient for the rapid manufacturing of dental restorations with good aesthetic features.