TY - JOUR
T1 - Effect of hydrothermal aging on the microhardness of high- and low-viscosity conventional and additively manufactured polymers
AU - Al-Haj Husain, Nadin
AU - Feilzer, Albert J.
AU - Kleverlaan, Cornelis J.
AU - Abou-Ayash, Samir
AU - Özcan, Mutlu
N1 - Publisher Copyright:
© 2022 Editorial Council for The Journal of Prosthetic Dentistry
PY - 2022/10
Y1 - 2022/10
N2 - Statement of problem: Studies on the microhardness of novel additively manufactured polymers compared with well-established low- and high-viscosity composite resins with regard to chemical composition are lacking. Purpose: The purpose of this in vitro study was to evaluate the effect of hydrothermal aging on the microhardness of various conventional and additively manufactured polymers. Material and methods: Cylindrically shaped specimens (N=240, n=10 per group) (Ø10×2 mm) were either additively manufactured (6 groups) or conventionally (6 groups) manufactured by using 3D (Optiprint Temp [OP; Dentona]; C&B MFH [ND; NextDent]; Saremco print CROWNTEC [SA; Saremco Dental AG]; Temp Print [TP; GC]; 3DELTA ETEMP [DM; Deltamed]; MED690 [ST; Stratasys, Ltd]) or conventional low (Gradia Direct [GR; GC]; Clearfil Majesty [CM; Kuraray Noritake]; Tetric EvoCeram [TE; Ivoclar Vivadent AG]) and high (Gradia Direct Flo [GR-F; GC]; Clearfil Majesty Flow [CM-F; Kuraray Noritake]; Tetric EvoFlow [TE-F; Ivoclar Vivadent AG]) viscous materials. All specimens were randomly allotted to 2 different aging methods (no-aging [dry] or aging by thermocycling [TC], ×6000, 5 °C-55 °C) and Vickers hardness (VH) tested (ZHV30; Zwick). Three indentations were made on each specimen (0.98-N load, duration 15 seconds). The calculated average microhardness value of each specimen was statistically analyzed by using 2-way ANOVA and Tukey post hoc tests (α=.05). Two-parameter Weibull distribution was calculated to predict the reliability of material type and aging method on VH. Results: The mean ±standard deviation VH ranged between 17 ±0.5 VHN and 68 ±0.5 VHN in the following ascending order: group STa<OPb, NDb<SAc, TPc<GRd, GR-Fd<DMe, TE-Fe<CMf<TEg<CM-Fh. The groups with the same superscript were not significantly different from each other (P>.05). The mean ±standard deviation of HV for aged (37 ±1 VHN) and nonaged (35 ±1 VHN) specimens were statistically similar (P>.05). The Weibull distribution values presented the highest shape for the aged group SA (37.81). Conclusions: The choice of the material had a significant effect and resulted in lower hardness for the 3-dimensionally printed materials than for the conventional composite resins. Under fatigue conditions, the choice of the material showed no significant difference when the Vickers microhardness was evaluated.
AB - Statement of problem: Studies on the microhardness of novel additively manufactured polymers compared with well-established low- and high-viscosity composite resins with regard to chemical composition are lacking. Purpose: The purpose of this in vitro study was to evaluate the effect of hydrothermal aging on the microhardness of various conventional and additively manufactured polymers. Material and methods: Cylindrically shaped specimens (N=240, n=10 per group) (Ø10×2 mm) were either additively manufactured (6 groups) or conventionally (6 groups) manufactured by using 3D (Optiprint Temp [OP; Dentona]; C&B MFH [ND; NextDent]; Saremco print CROWNTEC [SA; Saremco Dental AG]; Temp Print [TP; GC]; 3DELTA ETEMP [DM; Deltamed]; MED690 [ST; Stratasys, Ltd]) or conventional low (Gradia Direct [GR; GC]; Clearfil Majesty [CM; Kuraray Noritake]; Tetric EvoCeram [TE; Ivoclar Vivadent AG]) and high (Gradia Direct Flo [GR-F; GC]; Clearfil Majesty Flow [CM-F; Kuraray Noritake]; Tetric EvoFlow [TE-F; Ivoclar Vivadent AG]) viscous materials. All specimens were randomly allotted to 2 different aging methods (no-aging [dry] or aging by thermocycling [TC], ×6000, 5 °C-55 °C) and Vickers hardness (VH) tested (ZHV30; Zwick). Three indentations were made on each specimen (0.98-N load, duration 15 seconds). The calculated average microhardness value of each specimen was statistically analyzed by using 2-way ANOVA and Tukey post hoc tests (α=.05). Two-parameter Weibull distribution was calculated to predict the reliability of material type and aging method on VH. Results: The mean ±standard deviation VH ranged between 17 ±0.5 VHN and 68 ±0.5 VHN in the following ascending order: group STa<OPb, NDb<SAc, TPc<GRd, GR-Fd<DMe, TE-Fe<CMf<TEg<CM-Fh. The groups with the same superscript were not significantly different from each other (P>.05). The mean ±standard deviation of HV for aged (37 ±1 VHN) and nonaged (35 ±1 VHN) specimens were statistically similar (P>.05). The Weibull distribution values presented the highest shape for the aged group SA (37.81). Conclusions: The choice of the material had a significant effect and resulted in lower hardness for the 3-dimensionally printed materials than for the conventional composite resins. Under fatigue conditions, the choice of the material showed no significant difference when the Vickers microhardness was evaluated.
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U2 - 10.1016/j.prosdent.2022.08.022
DO - 10.1016/j.prosdent.2022.08.022
M3 - Article
AN - SCOPUS:85139315148
SN - 0022-3913
VL - 128
SP - 822.e1-822.e9
JO - Journal of Prosthetic Dentistry
JF - Journal of Prosthetic Dentistry
IS - 4
ER -