2D and 3D pore structure characterization of bi-layered porous polyethylene barrier membrane using SEM and micro-CT

Abstract

Barrier membrane is an essential component in guided bone regeneration for successful bone augmentation in implant dentistry. The microstructure of barrier membrane can remarkably impact its mechanical properties and biological performances. This study was aimed to investigate the pore structures of a bi-layered porous polyethylene (PPE) barrier membrane by 2D and 3D characterization techniques. Two opposite sides of PPE barrier membrane were imaged with scanning electron microscope and micro-computed tomography (micro-CT). The 2D and 3D pore characteristics were then analysed with associated software, respectively. Both techniques similarly showed that PPE barrier membrane comprised two different structures including one with low porosity (smooth) and one with high porosity (coarse) as designed. In 2D analysis, both surfaces possessed similar positively skewed distributions in pore area and circle diameter. The smooth side had significantly smaller pore amount, pore density, surface porosity, pore area, circle diameter, Feret diameter and aspect ratio, but larger roundness, circularity and solidity than the coarse side (p < 0.05). In 3D analysis, the smooth side possessed significantly smaller pore diameter and volume porosity than the coarse one (p 0.05). The combination of 2D and 3D techniques could be effectively employed to characterize the pore microstructure and morphology of PPE barrier membrane. The limitations of each technique were also discussed.