# Preclinical Performance of Customized Polycaprolactone-Based Hybrid Bone grafts
## 4 Discussion  
After analyzing the results obtained in the cell viability assay (MTT), no significant differences were found between the materials; the results for the different samples according to absorbance and elapsed time were very similar, giving rise to values that were well above \(p<0.05\). The \(p\)-value delimits whether there are significant differences between samples. The results obtained in terms of absorbance according to the concentration of PCL turned out to be \(p=0.6217\), and according to the absorbance and number of hours elapsed, \(p=0.2019\), so the differences were not considered significant. These results were compared with each other and with the control group, guaranteeing that the materials under study did not cause any cell damage to the cultures apart from that which occurred in the control. The cell viability results were positive, with a high rate of live cells per material, thus agreeing with different studies in which the biocompatibility of PCL was analyzed, such as that by [PERSON] et al., in which it was concluded that PCL is a material with a high rate of fibroblast proliferation due to its high biocompatibility, which gives it favorable properties as a scaffolding material in bone regeneration [20]. Another study with favorable results with regard to the biocompatibility of polycaprolactone in periodontal ligament cells is the study by [PERSON] et al., in which it was observed that the material was biocompatible and did not present harmful effects on the tissues supporting the tooth. In this research, the use of PCL in clinical applications such as dental implants was also analyzed, concluding that the materials characteristics are favorable for the union and growth of periodontal cells around it [21]. In the research carried out by [PERSON] et al., the authors also concluded that synthetic polymers such as polycaprolactone demonstrated favorable results in terms of cell viability, demonstrating that they are non-toxic and exhibited high biocompatibility. The novelty of \begin{table}
\begin{tabular}{c c c} \hline \hline
**Inmersion Time** & **Materials** & **Living Cells/Field** \\ \hline \multirow{3}{*}{24 h} & CONTROL & 96.14\% \(\pm\) 1.23 \\ \cline{2-3}  & PCL 95 & 96.22\% \(\pm\) 1.28 \\ \cline{2-3}  & PCL 90 & 96.48\% \(\pm\) 0.94 \\ \hline \multirow{3}{*}{48 h} & CONTROL & 95.54\% \(\pm\) 0.99 \\ \cline{2-3}  & PCL 95 & 96.15\% \(\pm\) 1.62 \\ \cline{2-3}  & PCL 90 & 95.75\% \(\pm\) 1.77 \\ \hline \multirow{3}{*}{72 h} & CONTROL & 95.98\% \(\pm\) 2.05 \\ \cline{2-3}  & PCL 95 & 95.20\% \(\pm\) 0.97 \\ \cline{1-1} \cline{2-3}  & PCL 90 & 95.45\% \(\pm\) 1.49 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Number of living cells/well (mean \(\pm\) standard deviation). Figure 4: (**a**). Cells stained with Hoechst. (**b**). Image using Fiji program. this study was that a synthetic material, i.e., PCL, was combined with natural materials such as collagen membranes, leading to satisfactory results for the development of cell lines in tissue engineering [22]. In the present in vitro research, PCL combined with strontium was used as one of the materials along with hydroxyapatite; this combination of components has already been analyzed thoroughly in other preclinical studies. In an article published by [PERSON] et al., both the toxicity and osteogenic capacity in bone regeneration of both materials when combined were analyzed. Nanohydroxyapatite is the main mineral component of bone, which, when combined with strontium ions, has been shown to have better biological and mechanical capabilities. The results of this study showed that strontium-ionized hydroxyapatite has higher levels of osteoclast, a hormone related to bone production [23]. In another similar study carried out by [PERSON] et al., it was shown that the addition of Sr to HA leads to an improvement in osteogenic capacity. As HA has good biocompatibility and osteoconductivity, when combined with Sr, it can enhance both properties to initiate osteogenesis [24].