| The applications and developments of dental implant technology have become one of indexes of the level of medical care and social civilization~ The integration of the biological technology, material science, life science, human science, and the stornatology is making the traditional implant materials transfonned into the bioactive materials. In the past, the standards of biocompaiibility were mainly centered on the security principles; conuastively, modem concepts on the biocompatibility put more emphases on the biologically functional principles. Therefore, in addition to the security propeiiies, new implant materials shall also be able to stimulate proper host responses when being used and can achieve ideal biological bonding ~ith the body tissue according to the design. There are still some problems existing in the clinical usage of dental implants. These problems brought huge inconvenience to both patients and doctors, and inhibited the dental implants from being ~idely useL All these problems can be related to the imperfectness of the integration of implants ~~ith the host tissue, because this is still the final reason for most implant failures. So, how to improve the osseointegration is still a challenge we are facing. To solve this problem. the bioactivity and biocompafibility of the implant materials should be enhanced continuously. If we can pie-immobilize sonic osterblast-favouite bioactive factors on the implant surface, then we can make the interface reaction under control, and, the bioactivity of the materials will be improved to a new level. Based on the latest finding of the cell adhesion biology, this project is aimed at the construction of a bioactive RGD coating on the material surface through covalent bonding. Some new techniques in modem chemistry and surface engineering ~rt used to achieve this, and in vitro experiments of the rat osteoblasts were employed to evaluate the biological effects of this new coating. -5- There are three major pans in our reseaxch 1. Immobilization of RGD on mateiiaic sw1aa~ 8IK! suxlace chemical analysis RGD were immobilized on the material surface by a new technique. Contact angle and surface energy were detected before and after irnmobilizaiiorL XI扴 analysis was used to examine the element component, element ratio, chemical environment and bonding stanis. FT-IR was used to checkout the chemical groups on the surface. Result After the immobilization of RGD, contact angle of two different medias on the surface ascended, and hence, the surface energy went down. XI扴 spectnuns of N, 0,5, C showed that the RGD molecules were covalently bonded to the surface. Element ratios and valences state found in this experiment agreed with the theoretical calculations about the RGD molecule showing that the molecules still kept d~ir initial stmcnire and configuratiorL FT-IR spectnim showed an obvious amide I apex indicating the existing of amino stnlcture. Comprehensive analyses indicated a highly organized and ordered distribution of the RGD on the suiface. 2. Isolation, culture and phenotype identification of the piimary rat nsteoblast Rat calvarial osteoblasts were isolated with continuous enzymatic digestion. Cells were purified by marglnal adhesion methocL Cell culture was carried out under normal condition. 2-3 cell generations were sele*ied for phenotype identi...
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