Hydroxyapatite Nanoparticle Modification of 3D-Printed Crown Resin: Effects of Concentration on Surface Roughness and Vickers Hardness After Thermocycling
Source abstract
Abstract
Background: This in vitro study evaluated the effect of hydroxyapatite nanoparticle (nano-HAp) incorporation on surface roughness and Vickers hardness of a 3D-printed crown resin after thermocycling. Methods: Disk-shaped specimens (N = 84) were modified and fabricated with 0%, 1%, 2%, and 3% nano-HAp. Surface roughness (Ra) and Vickers hardness (VHN) were measured before and after thermocycling (5000 cycles). Surface morphology was qualitatively assessed using FE-SEM. Data were analyzed using two-way mixed-design ANOVA (α = 0.05). Results: Thermocycling increased surface roughness and reduced hardness in all groups. Ra values were highest in the 3% nano-HAp group after thermocycling (1.16 ± 0.47 µm). Baseline Vickers hardness differed significantly among nano-HAp concentrations, and hardness decreased after thermocycling in all groups; however, the 3% nano-HAp group exhibited the highest post-thermocycling hardness values (24.66 ± 1.51 VHN), which should be interpreted in the context of its higher baseline hardness. FE-SEM observations suggested increased surface irregularities with higher nano-HAp concentrations after thermocycling. Conclusions: Nano-HAp incorporation influenced both surface and mechanical properties, with 3% concentration showing higher hardness after aging but increased roughness.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Bone Tissue Engineering Materials · 3D Printing in Biomedical Research · Dental materials and restorations
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Prosthodontics, Faculty of Dentistry, Biruni University, Merkezefendi Mahallesi, G/75 Sokak, 1-13 (M.G.), Zeytinburnu, Istanbul 34015, Turkey
Department of Restorative Dentistry, Faculty of Dentistry, Biruni University, Merkezefendi Mahallesi, G/75 Sokak, 1-13 (M.G.), Zeytinburnu, Istanbul 34015, Turkey
Department of Restorative Dentistry, Faculty of Dentistry, Istanbul University, Beyazıt Square (Beyazıt Meydanı) Fatih, Istanbul 34126, Turkey
Department of Pediatric Dentistry, Faculty of Dentistry, Biruni University, Merkezefendi Mahallesi, G/75 Sokak, 1-13 (M.G.), Zeytinburnu, Istanbul 34015, Turkey
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