Objective: When preliminary tests have confirmed a nano-hydroxyapatite (Nano-HA) content of 20% of the polylactic acid (PLA) composite material of Nano-HA interface fixation material for biomechanical requirements, there is a need for further observation of its biocompatibility and clinical applications, to provide reference data.
Methods: Preparation of Nano-HA content of 20% PLA composite Nano-HA bone substitute material and extract. The establishment of the negative control group (containing 10% fetal bovine serum in DMEM complete medium), experimental group (extract), the positive control group (mass concentration of 0.64% phenol), and a co-culture of rabbit bone marrow mesenchymal stem cells (rBMSC) and materials extraction liquid. Observation of the morphological changes in rBMSC in culture at time points of 3, 5, and 7 days, the use of the MTT assay, and determination of the relative growth in the above set of rBMSC in cell culture at 3, 5, and 7 days, to judge the material's cytotoxicity.
Results: With time, the absorbance value of the three groups of cells were significantly increased (P < 0.01). The relative growth of the rBMSCs in experimental group in the first 3, 5, and 7 days was 95.3%, 96.8% and 97.6%; the cytotoxicity was according to the national standards I; the difference was not significant (P > 0.05) between the the experimental group and the negative control group; there was a significant difference between the positive control group and the other 2 groups (P < 0.05). Cells in the experimental group were seen having normal morphology, and spindle-shaped adherent growth.
Conclusion: PLA composite artificial bone materials and Nano-HA show good cell compatibility, and the values for cytotoxicity, with reference to GB/T16886.5.2003 (China) standards, are in the safe range.
Keywords: cell compatibility; interface screw; nano-hydroxyapatite; polylactic acid.