TY - JOUR
T1 - Degradation of dental ZrO2-based materials after hydrothermal fatigue. Part I: XRD, XRF, and FESEM analyses
AU - Monteiro, Regina da Conceição Corredeira
AU - Braz Fernandes, Francisco Manuel
AU - Veiga, João Pedro Botelho
PY - 2012
Y1 - 2012
N2 - The aim was to investigate the effect of simulated low-temperature degradation (s-LTD) and hydrothermal fatigue on the degradation of three ZrO2-based dental materials. Lava, IPS, and NanoZr discs were randomly assigned to (1) Control-Storage in distilled water at 37°C; (2) Aging at 134°C for 5 h (s-LTD); (3) Thermocycling in saliva for 30,000 cycles (TF). XRD revealed that ZrO2 m phase was identified in all groups but TF increased the m phase only for Lava. Under the FESEM, Lava showed no alterations under s-LTD, but displayed corrosion areas up to 60 μm wide after TF. We conclude that TF accelerated the degradation of Lava through an increase in the m phase and grain pull-out from the material surface.
AB - The aim was to investigate the effect of simulated low-temperature degradation (s-LTD) and hydrothermal fatigue on the degradation of three ZrO2-based dental materials. Lava, IPS, and NanoZr discs were randomly assigned to (1) Control-Storage in distilled water at 37°C; (2) Aging at 134°C for 5 h (s-LTD); (3) Thermocycling in saliva for 30,000 cycles (TF). XRD revealed that ZrO2 m phase was identified in all groups but TF increased the m phase only for Lava. Under the FESEM, Lava showed no alterations under s-LTD, but displayed corrosion areas up to 60 μm wide after TF. We conclude that TF accelerated the degradation of Lava through an increase in the m phase and grain pull-out from the material surface.
KW - Zirconia
KW - Thermal fatigue
KW - Low-temperature degradation (LTD)
KW - Electron microscopy
U2 - 10.4012/dmj.2011-216
DO - 10.4012/dmj.2011-216
M3 - Article
C2 - 22447060
SN - 0287-4547
VL - 31
SP - 256
EP - 265
JO - Dental Materials Journal
JF - Dental Materials Journal
IS - 2
ER -