BACKGROUND: Stainless steels are low-cost, biocompatible, and strong but it is not biodegradable. Therefore, implants from stainless steel to fixate bone fractures necessitate a second surgery for implant removal. Biodegradable implants have been widely researched to avoid second surgery for implant removal. However, the implant's safety (toxicity) when absorbed into the body has not been widely elicited. METHODS: This research was a true experimental study to compare 4 implants: Stainless Steel, Magnesium-Based, Magnesium with Plasma Electrolytic Oxidation (PEO) coating, and magnesium with poly lactic acid (PLA) composite with MTT Assay. RESULTS: Cells exposed to stainless steel implants have significantly less optical density (0.3546) than the magnesium implants group (0.4685
p <
0.05). In the cell viability test, 56.5 % of cells in stainless steel survived, which is lower than the magnesium implant group with 79.3 % of cells surviving (p <
0.05). CONCLUSION: Magnesium implants were found to be significantly less toxic compared to stainless steel in this study. Amongst magnesium implants, magnesium with PEO coating was found to be the least toxic. However, further studies are required to ensure its safety in human usage.