Abstract: Objective Microstructure inspired by octopus suction cups was constructed on the surface of silicone rubber soft lining materials to evaluate its impact on adhesion and provide technical support for further producing tissue surface of complete denture base with it,and explore new ideas to improve retention of complete denture. Methods The experimental group was divided into five groups A-E (100, 200, 300, 400, 500 μm in diameters of suction cups). After producing negative mold of microstructures inspired by octopus suction cups with 3D printing, samples with different sizes were made by turning over the mold with silicone rubber material. The control group was plane silicone rubber samples without microstructure. Accuracy of production technology was evaluated and adsorption force of samples in each group was tested by universal mechanic material tester under simulated oral environment in vitro. Then statistical analysis was conducted. Results The deviation between 3D printing negative mold and predetermined size was about 7%-9%, while that between microstructures made from silicone rubber material and predetermined size reduced to 1%-5%. Bubbles can be found on some surfaces. Adhesion of different groups (the experimental groups A-E and the control group) was (0.20±0.04), (0.16±0.03), (0.13±0.04), (0.12±0.02), (0.14±0.02), (0.12±0.03)N. The adhesion in groups with diameter of 100 μm and 200 μm increased significantly, which was statistically different from the control group (P<0.05). Conclusion On the surface of silicone rubber soft denture liner, constructing microstructures inspired by octopus suction cups with diameter of 100 μm and 200 μm can improve adsorption. Using octopus suction cup-liked microstructures on tissue surface of complete denture base may improve its retention.

Key words: octopus suction cup, complete denture, bionic, silicone rubber soft lining material, adhesion