## 3 Results and Discussion
### Cytotoxicity Assessment  
All biomaterials, despite numerous favorable physicochemical characteristics, must meet the most important criteria, namely biocompatibility. This property is evaluated both quantitatively and qualitatively. Figure 13 reveals results of cytotoxicity study carried out using XTT assay which determines the amount of metabolically active cells. For the \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Sample** & **2 h** & **4 h** & **6 h** & **24 h** \\ \hline
**1** & \(7.7\times 10^{6}\) & \(*\) & \(*\) & \(*\) \\
**2** & \(7.2\times 10^{6}\) & \(*\) & \(*\) & \(*\) \\
**3** & \(7.3\times 10^{6}\) & \(*\) & \(*\) & \(*\) \\
**4** & \(6.2\times 10^{6}\) & \(*\) & \(*\) & \(*\) \\
**5** & \(5.7\times 10^{6}\) & \(5.31\times 10^{6}\) & \(4.65\times 10^{6}\) & \(3.14\times 10^{6}\) \\
**6** & \(5.9\times 10^{6}\) & \(5.21\times 10^{6}\) & \(4.33\times 10^{6}\) & \(2.63\times 10^{6}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 4: The results of the antibacterial properties study of the membranes against _Staphylococcus aureus_, CFU; \({}^{*}\)—impossible CFU count. Figure 12: Possible consequences of tooth extraction: (**a**) tooth loss due to caries: 1—dental biofilm formation, 2—caries leading to tooth loss, 3—empty socket after extraction, 4—bone resorption; (**b**) the most promising pathway including GBR procedure: 5—bone augmentation, 6—proliferating osteoblasts, 7—successful implantation and osseofixation without biofilm formation (**c**) alternative scenario without GBR procedure—socket filling with epithelial cells (**d**) issues with osseofixation and caries of adjacent teeth due to lack of biofilm formation prevention. experiment, _osteosarcoma_ cell line MG-63 has been used which is typically chosen for bone-dedicated medical devices. According to ISO-10993 [37] norm for medical device biological evaluation, the material can be described as non-toxic if compared to control cell culture cells viability, its viability is at least 70%. As shown in Figure 13, all samples did not exhibit any negative impact. Moreover, in all cases the number of viable cells was higher than for standard culture. Such results can be assigned to the BMP-2 incorporation as well as the use of raw materials known for their biocompatibility. This property was further investigated during a direct contact test [32; 33; 34; 35]. Based on the cell viability data (Figure 13), the samples exhibit a significant increase in cell viability compared to the control group. The average viability across all samples was approximately 138.83%, with individual sample values ranging from 128% to 144%. The highest increase was observed in samples at 144%, suggesting a robust effect on cell survival, while the lowest increase of 128% still demonstrates a clear improvement over the control. The moderate standard deviation (7.56%) indicates relatively consistent results across samples. These findings suggest that the tested samples have a positive impact on cell viability, which could be of interest for further research into their potential applications. As shown in Figure 14, photographs of cell cultures carried out in the presence of samples 5 and 6 created a complete monolayer. All cells are attached to the surface. They are flattened and connected. The cells had elongated morphology, typical for osteoblast-like cells. Also, the ECM formation process could be noticed. A positive impact on cell proliferation may also be assigned to the presence of MgO in the form of periclase nanoparticles, which acted as a filler. It is well known that Mg\({}^{2+}\) ions play a crucial role during bone regeneration. Firstly, magnesium hampers the activity of osteoclasts, cells responsible for bone resorption. At the same time, Mg\({}^{2+}\) stimulates osteoblasts differentiation and positively affects new tissue formation, helping to create extracellular matrix followed by its mineralization. Importantly, magnesium also affects neovascularization; thus, it enables the delivery of oxygen and nutrients to maturating bone.