Microstructure and biological activity of silicon-doped composite coatings fabricated by micro-arc oxidation on magnesium alloy
SURFACE AND INTERFACE ANALYSIS
Authors: Jiao, Yang; Ni, Xiao-hui; Zou, Guo-you; Ren, Liu-bao; Yi, Lei; Zhao, Quan-ming
Abstract
Among biomaterials, the mechanical properties of magnesium and its alloys are closest to those of human bone tissue, making these ideal materials for bone tissue repair and replacement. In order to further improve the biocompatibility and biological activity of the magnesium alloy AZ91D, micro-arc oxidation with a constant-current power supply mode was employed in this study in a silicate electrolyte solution. The resultant coating surface had a porous structure, and silicon was evenly distributed in it. Further, the results of in vitro experimental studies showed that the silicon-doped magnesium coating on the surface of the magnesium alloys has no obvious cytotoxicity, and it can induce the proliferation of osteoblasts and promote actin stretching. In addition, it has good biological activity and biocompatibility. Thus, the novel method developed in this study improves the potential for clinical applications of magnesium alloys.
Upper Blepharoplasty with Endoscopically Assisted Brow Lift to Restore Harmonious Upper Lid Arc Curvatures
PLASTIC AND RECONSTRUCTIVE SURGERY
Authors: Vaca, Elbert E.; Alghoul, Mohammed S.
Abstract
Background: Achieving excellent results in upper lid rejuvenation requires a balanced approach to address skin, muscle, fat, upper lid margin position, and brow aging changes. In the appropriately selected patient, brow lifting plays an essential complement to upper blepharoplasty to restore more youthful upper lid fold-to-pretarsal ratios. The goal of this study is to describe a safe and reproducible method to perform brow lifting and upper blepharoplasty. Methods: Medial to the temporal line of fusion, in-line with the brow peak, a 2-cm scalp incision is oriented parallel to the course of the deep branch of the supraorbital nerve to minimize the risk of nerve injury. The brow vector of pull is maximal in this location and secured to a monocortical bone channel with 3-0 polydioxanone. Lateral to the temporal line of fusion, an ellipse of scalp tissue is excised to gently elevate the brow tail. Upper blepharoplasty is performed in an individualized fashion to achieve a youthful contour of the upper lid fold. Results: The endoscopically assisted technique is designed to achieve tissue release under direct visualization. The brow-lift maximal vector of pull is centered over the brow peak and, to a lesser extent, at the brow tail to improve lateral upper lid fold height and a smooth contour of the pretarsal space. Muscle shaping sutures improve convexity of the lateral upper lid fold. Conclusion: In the appropriately selected patient, combined brow lift and upper blepharoplasty with muscle contouring are safe and effective techniques that help improve aesthetic upper lid topographic proportions.