Conventional and electric field-assisted ion exchange on glass-ceramics for dental applications

Effect of TiO2 on the sinter crystallization of nepheline glasses for dental application

“…Nuclear magnetic resonance (MAS-NMR) 23 Na and 27 Al MAS-NMR spectra were collected on glasses and glass-ceramics on a 600 MHz (14.1T) Bruker NMR spectrometer using a single resonance Bruker probe in a 4 mm rotor. Resonance frequencies of 159 and 156 MHz, a single pulse duration of 1 μs, and a recycling delay time of 1 s were used for 23 Na and 27 Al at a spinning rate of 12 kHz, respectively. The isotopic chemical shifts for each nucleus were referenced to 0 ppm using signals acquired from the standard reference solutions, sodium chloride (NaCl) and aluminum nitrate Al(NO 3 ) 3 .…”

“…Early studies on nepheline glass‐ceramics (bulk processed) reported the efficiency of TiO 2 as a nucleation agent 21–23 . The use of TiO 2 as a nucleating agent in nepheline‐based glass systems allowed the production of monolithic glass‐ceramics consisting of fine‐grained crystallites 24–27 . TiO 2 in certain surface crystallized aluminosilicate glasses is known to act as a nucleation agent to promote the development of a high density of internal nucleation sites and is used as a key to the achievement of controlled crystallization.…”

“…[21][22][23] The use of TiO 2 as a nucleating agent in nepheline-based glass systems allowed the production of monolithic glass-ceramics consisting of fine-grained crystallites. [24][25][26][27] TiO 2 in certain surface crystallized aluminosilicate glasses is known to act as a nucleation agent to promote the development of a high density of internal nucleation sites and is used as a key to the achievement of controlled crystallization. However, there are limited data on the effect of TiO 2 on nepheline-based glasses intended for processing into dental glass-ceramics via the powder route.…”

Kinetic study of the transformation of sodalite to nepheline

“…Nepheline can also be found as a crystalline phase developed by heat treatment during the manufacturing process of different materials. For instance, in recent years, glass–ceramic materials containing nepheline have been documented as efficient UltraViolet Light Emitting Diode (UV‐LED) color converters, 4 scaffolds for bone tissue regeneration 5 or for dental applications 6 . Nepheline is also reported in geopolymers, 7 self‐compacting repair mortars, 8 low thermally conductive ceramic foams, 9 or traditional ceramics 10 .…”

“…For instance, in recent years, glass-ceramic materials containing nepheline have been documented as efficient UltraViolet Light Emitting Diode (UV-LED) color converters, 4 scaffolds for bone tissue regeneration 5 or for dental applications. 6 Nepheline is also reported in geopolymers, 7 self-compacting repair mortars, 8 low thermally conductive ceramic foams, 9 or traditional ceramics. 10 Finally, nepheline can be also prepared through the thermal transformation of zeolites.…”