## 4 Discussion
### In-Vitro Biocompatibility Analysis
The optimum percentage of PLA addition was \(\leq\)5%; if this value is exceeded, it will lead to a high level of hemolysis. Hemolysis consists of rupturing of erythrocytes (RBCs) and the release of hemoglobin in the plasma. It has been known that the lysis of the erythrocytes occurs due to osmotic imbalance or physical disturbance due to interactions with external agents [85]. The presence of aloe vera increases the collagen amount and collagen cross-linking in the body, hence promoting tissue healing [86]. In addition, aloe vera consists of several other healing substances, such as glycoproteins and polysaccharides, which help reduce pain and work. Therefore, aloe vera addition to the porous composite circumvents the lysis of erythrocytes, hence decreasing the hemolysis rate by providing a protective response to the cells. A composite material designed for tissue engineering applications must possess minimum cytotoxicity. The current study showed that the porous Mg composite, consisting of an aloe vera solution as the therapeutic agent, had very low cytotoxicity, maintained even after coating with PLA. However, PLA coating reduced the cell viability by some amount, but further modifications and better sterilization could escalate these factors. Although this does not change the fact that the PLA coating does not show any immense signs of cytotoxicity with a viability percentage above 70%, the literature showed that this material is highly biocompatible and can be utilized in orthopedic applications [87, 88]. The current study utilized MTT assays to analyze the mitochondrial activity, which is related to cell proliferation [89]. Confocal microscopy revealed that the growth of osteocytes was normal and this is a good sign of a healthy response to the developed material. Similar results were obtained by [PERSON] et al. [90], where the presence of aloe vera enhanced the viability of 3T3 cells impressively. Many studies have considered aloe vera an added therapeutic agent and proven it is an excellent tissue-healing antibiotic material. Aloe vera in liquid form consists of 99% water, whereas in the dry state, it contains 55% polysaccharides, 17% sugars, 16% minerals, 7% proteins, 4% lipids, and 1% phenolic components [91]. These components play a significant role in tissue regeneration and provide therapeutic support to bone fragments' healing process. The flow cytometry studies showed similar results with aloe vera-loaded implants exhibiting the lowest level of apoptosis (both early and late) and 98% live cells. The cytotoxicity studies in the present work developed an insight into the cell death by apoptosis due to the reaction with the developed composites. A significant cellular response, including large histioctifiltration and particle phagocytosis, is evoked when composite degradation is prevalent. This causes an increase in the apoptosis rate, hence reducing the percentage of live cells. However, aloe vera's presence prevented this phenomenon from occurring by providing subsequent therapeutic shielding of the cells. Aloe vera consists of several biological components that provide several transport and activities of biological factors required in tissue regeneration. A mannose-rich polysaccharide called glucomannan and a growth hormone called gibberellin interact with the fibroblast's growth factor receptor to promote the activity and proliferation of the cell. Aloe vera based implants have also been promoted as an anti-cancerous drug in a study proposed by [PERSON] et al. [91], where curcumin/aloe vera was used with PCL electrospun membranes. [PERSON] et al. [92] developed electrospun fiber mats with aloe vera blended with PCL as dermal substitutes with excellent cell proliferation produced by 10% aloe vera addition. Therefore, based on the above literature, the proposed implant presented in the current study proved an effective implant composite material. The mechanism showing an effect of aloe vera addition on the inhibition against bacterial cells and growth of bone regeneration cells is shown in Figure 11b.