## 3 Results
### XRD Analysis  
Tricalcium phosphate (TCP) has four polymorphic forms [50]: \(\alpha\), \(\beta\), \(\alpha^{\prime}\), and \(\gamma\) (the last two are not of interest, because of their instability). As mentioned earlier in the text, \(\beta\)-TCP is famous for its remarkable osteoconductivity and biocompatibility. In contrast, the degradation rate of \(\alpha\)-TCP is much higher in relation to \(\beta\)-TCP [51]. As a result, the  
Figure 7: FTIR spectrum of \(\beta\)-TCP surfaces untreated/treated by laser irradiation at F = 1.66 and 2.07 J/cm\({}^{2}\), N = 5 and 10.  
higher local Ca\({}^{2+}\) and PO\({}_{4}\)\({}^{3-}\) concentration in body fluids, caused by the rapid dissolution of \(\alpha\)-TCP, could obstruct the bone formation [52]. To examine which TCP (\(\alpha\) or \(\beta\) form) was the primary calcium phosphate phase in our probes and to distinguish the differences between \(\alpha\)-TCP and \(\beta\)-TCP crystals, XRD analysis was performed. Figure 8 presents the X-ray diffraction patterns of control/\(\beta\)-TCP surfaces, analyzed in the 20 angle and treated by laser irradiation at F = 1.66 and 2.07 J/cm\({}^{2}\), N = 5 and 10. As can be seen from the figure, peaks of both \(\alpha\)-TCP and \(\beta\)-TCP are observed. The presence of \(\alpha\)-TCP was confirmed by the main reflection at 20 of 12.2\({}^{\circ}\), 22.3\({}^{\circ}\), 24.3\({}^{\circ}\), and 30.9\({}^{\circ}\), while the presence of \(\beta\)-TCP revealed the main reflection at 27.8\({}^{\circ}\), 25.9\({}^{\circ}\), 31.2\({}^{\circ}\), and 33.1\({}^{\circ}\)[53]. However, there exists a significant difference in the peak intensity of XRD patterns for \(\alpha\)-TCP and \(\beta\)-TCP, after fs-laser modification. At F = 2.07 J/cm\({}^{2}\) and N = 10 pulses, the detected majority of phases obtained from the inside part of the processed samples grooves is transformed from \(\beta\)-TCP to \(\alpha\)-TCP. Decreasing the values of laser parameters to F = 1.66 J/cm\({}^{2}\) and N = 5 or 10 leads to a reduction of the transformation of \(\beta\)-TCP into \(\alpha\)-TCP phase, while still allowing gentle surface processing. These results are crucial for the optimization of the laser parameters in order to obtain textured \(\beta\)-TCP substrates without the presence of unwanted \(\alpha\)-TCP secondary phases. It can be concluded that both XRD and FTIR analyses contributed to optimizing the fs-laser modification parameters for further biological evaluation with MC3T3 osteoblasts cell line on \(\beta\)-TCP grooved samples. Cell Culture and Proliferation on Laser Patterned \(\beta\)-TCP and ATZ (Alumina Toughened Zirconia) Ceramic Scaffolds  
In order to determine the cellular behavior of diverse surface textures, the sample area was divided into two zones, patterned and non-modified areas. The spacing between separate stripes was controlled by the scanning velocity as well as in the second mode of operation by a selection of the distance separation between the individual spots, created by the laser--Table 2.  
Figure 8: X-ray diffraction patterns of control/\(\beta\)-TCP surfaces treated by laser irradiation at F = 1.66 and 2.07 J/cm\({}^{2}\), N = 5 and 10. The attachment of cells onto a ceramic material is an important factor in different cellular processes, such as cell proliferation, and is thus important to consider while choosing a suitable biomaterial. Laser-patterned surfaces forming grooves are known to affect the morphology of the cell by elongation. The results from the live/dead staining on day 7 showed that all patterned substrates indicate affinity to orientate MC3T3 cells over the 7-day culture period. Figures 9 and 10 show representative images obtained by fluorescence microscopy, after 7 days of the culture of MC3T3 cell lines on diverse designs of topographically textured surfaces. To have a comparison with diverse types of ceramic scaffolds, fluorescent measurements were also done on laser-treated ATZ samples (Figure 10).