Fig 1.
Schematic of the irradiation system of the LAB process for the standard-sized PEEK substrate (3 mm × 10 mm × 10 mm).
Fig 2.
SEM images (a) and SEM-EDX spectra (b) of the surfaces of the untreated PEEK substrate and those after the LAB process at 2, 4, or 6 W/cm2 for 30 min. The C peak in (b) is due to the carbon coating prior to the SEM-EDX analysis and the base PEEK substrate.
Fig 3.
TEM image (a), electron diffraction pattern (b), and TEM-EDX spectrum (c) of the precipitate scraped from the surface of the LAB-processed (2 W/cm2, 30 min) PEEK substrate. Rings observed in (b) were indexed to hydroxyapatite (JCPDS No. 09–0432).
Fig 4.
SEM images (a) and SEM-EDX spectra (b) of the surfaces of the untreated PEEK substrate and those after the LAB process at 2 W/cm2 for 5, 10, or 30 min. The C peak in (b) is due to the carbon coating prior to the SEM-EDX analysis and the base PEEK substrate.
Fig 5.
Digital camera image (a), SEM (b) images, and SEM-EDX spectra (c) of the non-irradiated and laser-irradiated regions of the LAB-processed (2 W/cm2, 30 min) PEEK substrate surface. The C peak in (b) is due to the carbon coating prior to the SEM-EDX analysis and the base PEEK substrate.
Fig 6.
Temperature variations of the CP solution with and without the PEEK substrate during laser irradiation at 2 W/cm2 without a temperature-controlled water bath.
Data are expressed as the average ± standard deviation (n = 4).
Fig 7.
SEM images (a) and contact angles of water droplet (b) of the surfaces of the untreated PEEK substrate and those after laser irradiation in ultrapure water at 2 W/cm2 for 5, 10, or 30 min. Data in (b) are expressed as the average ± standard deviation (n = 3).
Fig 8.
Results of cell proliferation assay (OD450: relative to the number of viable cells) (a) and cytotoxicity assay (OD490: relative to the concentration of LDH from dead or damaged cells) (b) for the untreated and LAB-processed (2 W/cm2, 30 min) PEEK substrates after cell culture for 1, 3, 5, and 7 d. Data are expressed as the average + standard deviation (n = 4, * p < 0.05, ** p < 0.01).
Fig 9.
DAPI-stained cells on the untreated and LAB-processed (2 W/cm2, 30 min) PEEK substrates after 7 d culture.
Fig 10.
SEM images (a, b) and SEM-EDX spectra (c) of the non-irradiated and laser-irradiated regions of the LAB-processed (2 W/cm2, 30 min) PEEK substrate surface after the SBF test (a, c) and after the subsequent tape-detaching test (b). The Au peak in (c) is due to the gold coating prior to the SEM-EDX analysis.