Papers by Keyword: Implant Surface

Abstract: Amid increasing numbers of artificial joint implantation surgeries, improving the quality of life (QOL) for patients by accounting for individual variation is a primary concern. Thus, we aim to develop implants designed to optimize the interface between implant and living bone. In particular, for ensuring long-term durability and stability after implantation, we focused on inducement of appropriate alignment for biological apatite (BAp) crystallites and the related collagen (Col) fibers as a bone quality parameter. In this study, we predicted that when stress is applied to bone, the BAp/Col preferential alignment can be formed on the basis of our previous result if osteocytes, which can sense its around stress field, are in an environment that is aligned with the principal stress vector. We tested this idea by introducing grooves with the different angles on the implant surface, considering the principal stress direction. This study finally analyses the effect of stress transmission by a load at the proximal femur on the bone inside and near the grooves by using a mechanical simulation in which groove angles and positions can be changed on the implant surface. Furthermore, we carried out animal experiments using a 2-years-old beagle to examine the effect of grooves in the principal stress direction on the surface in vivo. As a result, bone formation in grooves on the implant surface strongly depends on the grooved angle to the principal stress vector and the grooved position on implants. The new bone preferentially formed inside the grooves parallel to the principal stress direction predicted by three dimensional finite element analysis (FEA) in the proximal area of beagle femur.

Abstract: Because of its high biocompatibility, hydroxyapatite(HA) has been considered as a good blasting material. DNA microarray is a new molecular technology that enables the analysis of gene expression in parallel on a very large number of genes, spanning a significant fraction of the human genome. It is a qualitive analysis (e.g. it can differentiate each single gene) and quantitative, since it has the sensitivity to detect a change of expression level in the investigated cells when compared to normal samples. The aim of this study is to define the cell attachment and the genetic effect of machined surface implant and RBM (resorbable blast media) surface implant on the osteoblastic cell (MC3T3-E1 osteoblastic cell line) by cDNA microarray slide containing 21575 genes. Cells were cultured on machined grade 4 titanium disks(Group 1, machined surface) and disks of RBM (Group 2) and the samples were moved to new dishes and media were added and the plated disks were cultured for 24 hours. Total RNA extraction was performed with Qiagen mini kit (Qiagen, Chatsworth, CA, USA) for microarray assay. Microarray assay after culturing the cells on the machined surface and RBM surface revealed that osteoinductive molecules appeared more prominent on the RBM surface, whereas the adhesion molecules on the biomaterial were higher on the machined surface than RBM surface.

Abstract: One of the techniques for modifying Ti implant surface is an anodization. This method is an electrochemical one that forms rough, thick, and porous oxide films. To compare the gene expression from the cells cultured on the different implant surface, cDNA microarray have been performed. MC3T3-E1 cells were cultured on titanium disks. The control groups were cultured on the machined surfaces(MS). The experimental groups cultured on the anodized titanium surfaces(AS). Microarray assay 48 hours after culturing the cells on the machined surface and anodized surface revealed that osteoinductive molecules appeared more prominent on the anodized surface, whereas the adhesion molecules on the biomaterial were higher on the machined surface than anodized surface, which will affect the phenotype of the plated cells depending on the surface morphology.