Abstract:

BACKGROUND: Rapid prototyping technology has been widely used in surgery simulation and tissue engineering research. However, spot surgical stimulation and preoperative instruction on accuracy of model is very high, and the model in the operation should require its avirulence to humans.
OBJECTIVE: To evaluate the accuracy and cytotoxicity of the rapid prototyping models with different post treatment.
METHODS: Standard cylindrical models were prepared by selective laser sintering method, followed by paraffin or resin treatment, the height and bottom diameter of the models was measured and its accuracy was assessed. Then, MTT method was used to study the cytotoxicity of model on mouse fibroblast L929 and mouse preosteoblast MC3T3-E1. The experiment was divided into five groups: paraffin-treatment group, resin-treatment group, negative control group (non-treatment sample), blank group (flesh DMEM medium), and positive control group (5% (v/v) DMSO). After 2 days culturing, the absorbance of cells at 490 nm was tested, the relative growth rate was calculated and the cytotoxicity grade of models was evaluated.
RESULTS AND CONCLUSION: The accuracy and error of models treated by paraffin, resin and the original model was 95%-97% and 0.5-1 mm respectively. After 2 days L929 and MC3T3-E1 cells cultured by leaching liquor of models, the relative growth rates of cells were more than 80% in each group. Moreover, rapid prototyping models treated by paraffin had low cytotoxicity on L929 and MC3T3-E1 cells, while resin-treatment and non-treatment models had no cytotoxicity on L929 and MC3T3-E1 cells, the grade of cytotoxicity was 0-1.