Development and characterisation of dental composites containing anisotropic fluorapatite bundles and rods
| Autor: | Matthew J. German, Asmaa Altaie, Ali Marie, Paul Franklin, David Wood, N. L. Bubb |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Scanning electron microscope Flexural modulus Fluorapatite Composite number 030206 dentistry 02 engineering and technology 021001 nanoscience & nanotechnology Composite Resins 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Fracture toughness chemistry Flexural strength Mechanics of Materials Apatites Materials Testing Vickers hardness test Bisphenol A-Glycidyl Methacrylate General Materials Science Composite material 0210 nano-technology General Dentistry Fluoride |
| Zdroj: | Dental Materials. 36:1071-1085 |
| ISSN: | 0109-5641 |
| DOI: | 10.1016/j.dental.2020.05.003 |
| Popis: | Objectives: To develop dental composites incorporating fluorapatite (FA) crystals as a secondary filler and to characterise degree of conversion, key mechanical properties and fluoride release. Methods: FA rod-like crystals and bundles were hydrothermally synthesised and characterised by scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD) and 19F MAS-NMR. Composites were formulated containing BisGMA/TEGDMA/BisEMA and barium-aluminium-silicate glass (0FA). FA crystals were incorporated at 10 (10FA), 20 (20FA), 30 (30FA) and 40 wt% (40FA) maintaining a filler content of 80 wt% (63–67 vol%). Degree of conversion (DC), flexural strength (FS), flexural modulus (FM), fracture toughness (K1C), Vickers hardness (HV) and 2-body wear were measured. Fluoride release was measured in neutral and acidic buffers. Results: XRD and 19F MAS-NMR confirmed that only FA was formed, whilst SEM revealed the presence of single rods and bundles of nano-rods. DC ranged between 56–60% (p > 0.05). FA composites showed lower FM and lower FS (p < 0.05), but comparable wear resistance and HV (p > 0.05) to 0FA. 30FA and 40FA showed similar K1C to 0FA (p > 0.05), with SEM showing evidence of toughening mechanisms, whereas 10FA and 20FA showed lower K1C (p < 0.05). FA containing composites released fluoride that was proportional to the amount of FA incorporated (p < 0.05) but only under acidic conditions. Significance: The addition of FA to the experimental composites reduced strength and stiffness but not the DC, hardness or wear rate. 30FA and 40FA had a higher K1C compared to other FA groups. Fluoride release occurred under an accelerated acidic regime, suggesting potential as a bioactive ‘smart’ composite. |
| Databáze: | OpenAIRE |
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