Mechanical Anisotropy and Fatigue Behavior of 3D-Printed Dentures: A Comparison with CAD/CAM Milled Bases After Thermomechanical Aging
Source abstract
Abstract
To investigate the effect of print orientation (0°, 45°, and 90°) and artificial aging on flexural strength and fatigue resistance of 3D-printed denture bases compared to CAD/CAM milled controls, we fabricated 320 maxillary complete dentures, divided into 8 groups based on the fabrication method: horizontal, oblique, and vertical printing, alongside milled controls. Half of the specimens in each group were pre-conditioned via thermocycling and 240,000 cycles of chewing simulation. All specimens underwent static flexural strength testing and cyclic fatigue testing, followed by SEM fractography. The CAD/CAM milled bases demonstrated the highest mechanical durability, with non-aged specimens peaking at 149.43 ± 5.35 MPa. The horizontally 3D-printed non-aged specimens yielded the highest flexural strength (101.14 ± 4.80 MPa), while vertically printed aged specimens recorded the lowest (70.35 ± 8.18 MPa). Artificial aging degraded flexural strength uniformly across all orientations. Conversely, cyclic loading disproportionately devastated the older people’s vertical group, resulting in a 70% fracture rate. Fractography corroborated these findings, revealing severe interlaminar delamination in vertical builds, contrasting with cohesive, trans-layer fractures in horizontal prints. In conclusion, Horizontal orientation provided improved structural durability; however, CAD/CAM milled dentures remain superior and are recommended for long-term clinical applications.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Dental materials and restorations · Additive Manufacturing and 3D Printing Technologies · Dental Implant Techniques and Outcomes
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Prosthetic Dental Sciences, College of Dentistry, Qassim University, Saudi Arabia
School of Computing, University of Eastern Finland, Yliopistokatu 2, 80100 Joensuu, Finland
References (45)
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