1.Cytotoxicity and mechanical properties of the prosthetic liner
Huiqin LUAN ; Jingfang BI ; Sainan WU ; Weiyan REN ; Hongmei LIU ; Yingying ZHANG ; Zengyong LI
Chinese Journal of Rehabilitation Theory and Practice 2022;28(4):479-483
Objective To investigate the current status of cytotoxicity and mechanical properties of the prosthetic liner on the market in China.Methods Six kinds of liner were collected, namely domestic 6 mm thick foam liner (A), domestic 5 mm thick EVA foam liner (B), German 5 mm thick EVA foam liner (C), Germany 12 mm thick PE foam liner (D), Iceland 3 mm thick silicone liner (E) and Germany 4 mm thick gel liner (F). Microscopic observation and thiazole blue colorimetry were used to detect the cytotoxicity. The content of small organic molecules was determined by the consumption of potassium permanganate. The tensile strength, elongation at break (%), and 100% tensile strength of the prosthetic liner were tested by material mechanics testing machine. The hardness was tested using the Shore hardness tester oo type.Results The cytotoxicity was grade 2 for prosthetic liners A, B, C and D, and was grade 0 for E and F. The redox substance content of prosthetic liners A、B、C exceeded 150 mg/kg. Except the prosthetic liner C, the hardness of the other products were all ≤ 70 HA. Except prosthetic liner D, the tensile strengths were > 1 MPa, breaking elongations were > 120.0%, 100% tensile strengths were > 0.9 MPa for other products.Conclusion Due to materials and production processes, the cytotoxicity and mechanical properties of the six samples are quite different.