title: A new approach to improve the local compressive properties of PPDO self-expandable stent.
abstract: The radial performance of bioabsorbable polymeric intravascular stents is extremely important in assessing the efficiency of these devices in expanding narrow lumen, reducing stent recoil, and recovering to their original states after suffering from pulsating pressure. However, these stents remain inferior to metallic stents. Several thermal treatment conditions (60°C, 80°C, and 100°C for 1h) were investigated to improve the characteristics of poly(p-dioxanone) (PPDO) self-expandable stents. The local compressive force, stiffness, and viscoelasticity of these stents were also evaluated. Wide-angle X-ray diffraction and different scanning calorimetry measurements were performed to evaluate the recrystalline and thermodynamic changes of molecular chains. The declining conformer entropy of PPDO monofilaments was examined via energy analysis. The untreated stents had compressive modules of 514.80±70.59mN/mm, which was much higher than those of 80°C and 100°C treated stents (332.35±66.08mN/mm and 394.31±64.71mN/mm, respectively). Nevertheless, 100°C annealing stents had less stress relaxation and prior elastic recovery rate of 82.32±3.43mN and 92.55±1.61%, respectively, showing a much better shape stability than untreated stents (139.51±16.67mN and 86.18±3.57%, respectively). These findings present important clinical implications in the stent manufacturing process and warrant further study to develop new bioabsorbable stents with outstanding clinical efficacy.
authors.affiliation: College of Textiles, Donghua University, Shanghai 201620, China; Key Laboratory of Textile Science and Technology of Ministry of Education and College of Textiles, Donghua University, 2999 North Renmin Road, Shanghai 201620, China.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhao
authors.affiliation: College of Textiles, Donghua University, Shanghai 201620, China; Key Laboratory of Textile Science and Technology of Ministry of Education and College of Textiles, Donghua University, 2999 North Renmin Road, Shanghai 201620, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Xue
authors.affiliation: College of Textiles, Donghua University, Shanghai 201620, China; Key Laboratory of Textile Science and Technology of Ministry of Education and College of Textiles, Donghua University, 2999 North Renmin Road, Shanghai 201620, China. Electronic address: wfj@dhu.edu.cn.
authors.forename: Fujun
authors.initials: F
authors.lastname: Wang
authors.affiliation: College of Textiles, Donghua University, Shanghai 201620, China.
authors.forename: Chenglong
authors.initials: C
authors.lastname: Yu
authors.affiliation: College of Textiles, Donghua University, Shanghai 201620, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Xu
authors.affiliation: College of Textiles, Donghua University, Shanghai 201620, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Hao
authors.affiliation: College of Textiles, Donghua University, Shanghai 201620, China; Key Laboratory of Textile Science and Technology of Ministry of Education and College of Textiles, Donghua University, 2999 North Renmin Road, Shanghai 201620, China. Electronic address: wanglu@dhu.edu.cn.
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
mesh_terms: D019245:Compressive Strength; D004146:Dioxanes / Q000032:analysis*; D006801:Humans; D008422:Materials Testing; D011108:Polymers / Q000032:analysis*; D011312:Pressure; D015607:Stents
chemical_list: D004146:Dioxanes; D011108:Polymers; C079733:poly-4-dioxan-2-one
keywords: Conformer entropy; Crystallinity; Local compression; PPDO braiding stent; Thermal treatment