Journal Article

Fracture resistance of nanocomposite 3D-printed resins designated for teeth fabrication: An in vitro analysis before and after thermal aging version 3; peer review: 2 approved with reservations

Y. Alboryh, Shaymaa, Y. Alshaikhnasser, Farah, A. Alhassan, Fatimah, M. Alatiyyah, Fatimah, M. Gad, Mohammed, Q. Khan, Soban, H. Al Dawood, Zainab, Tharwat Al Ammary, Ahmed, Akhtar, Sultan, F. Almedarham, Rawan, A. Balhaddad, Abdulrahman, A. Nassar, Essam

2025

Overview

Background: this study was to evaluate the fracture resistance and elastic modulus of modified 3D-printed resins containing zirconium dioxide nanoparticles (ZNPs) and silicon dioxide nanoparticles (SNPs). Methods: Tooth-colored 3D-printed resin samples (ASIGA (AS)) and NextDent (ND)) were modified with silanized ZNPs and SNPs. Five groups (n=100) were prepared for each resin type, one without nanoparticles, and four groups (n=20 per group) with varying nanoparticles concentrations (0.5 wt. %ZNP, 1 wt.%ZNP, 0.5 wt.%SNP, and 1 wt.%SNP). Half of the specimens (110 samples) were subjected to thermal aging (TA; 5000 cycles). The fracture resistance and elastic modulus were evaluated, followed by Fourier-transform infrared and scanning electron microscopy analyses. An analysis of variance and Tukey's post-hoc test were applied for data analysis. Results: Incorporating SNPs and ZNPs into the ND material significantly improved the fracture resistance compared to that of the control group, with 1 wt.%SNP showing the highest resistance (1405.9±128.4 N) and 0.5 wt.%ZNP the lowest (1047.5±100.6 MPa). However, the elastic modulus decreased notably with these additions, with the ND control group (3097.5±115.9 MPa) exhibiting the highest elastic modulus and ZNP groups (1772.0±128.8 MPa) exhibiting the lowest. In between NPs-reinforced groups per NPs type, there were no significant differences between SNPs groups (p=0.064) as well as ZNPs groups (p=0.072). For the AS material, similar enhancements in fracture resistance occurred; however, reductions in the elastic modulus were more significant in the ND material (p<0.001*). For the AS material, SNP and ZNP addition improved fracture resistance relative to that of the control group. Post-TA, the elastic modulus significantly decreased in both the ND and AS materials (p < 0.05). Compared to ND material, the increase in fracture resistance was less pronounced in the AS material. Conclusion: The addition of ZNPs and SNPs increased the fracture resistances of both materials. TA significantly reduced the fracture resistance and elastic modulus in most NP-incorporated groups. The ASIGA resin demonstrated superior performance and enhancements were more prominent which demonstrates promising characteristics for clinical use.