Biomaterials

Biography

Biography: Hyun-Do Jung

Abstract

Titanium (Ti) and its alloys are used extensively for orthopedic and dental implants, owing to their good mechanical and biological properties. Recently, biomedical implants were improved osteoinductivity incorporating with growth factors such as bone morphogenetic proteins (BMPs). However, growth factors deposited on the implant surface are often easily released with a rapid burst. In this study, we fabricated BMPs-embedded titanium implants using new techniques and improve the potential for embedment of growth factors. For growth factor loading, porous Ti discs were soaked in BMP-2 in a vacuum and then air-dried. After drying, coated porous Ti discs were pressed by uniaxial press. The BMP-2 release test was performed in PBS at 37 °C for 90 days. In vitro test were monitored by MTS assay and ALP activity. After pressing, the Ti was well densified without any noticeable defects such as cracking or large voids. It should be noted that the porosity decreased as pressure increased and that the Ti was almost densified when the pressure reached to 1500 Mpa. The BMP-2 was coated in the inside of pores before pressing and released through micropores slowly. From the release kinetics it is clearly evident that the BMPs-embedded Ti remarkably reduces the initial burst release of Ti compared to porous Ti. This release trend can be explained on the basis of the narrow pores like an ant tunnel when pressed. These narrow pores allows for a more controlled and long-termed release. The cell viability after culturing for 3 days was not influenced very much by embedded BMP. However, the ALP activity of the cells cultured for 7 days on embedded Ti was significantly higher than that on the bare Ti for the same period of time. In vivo performances of the Ti embedded with BMPs were assessed using a cortical defect model in rabbit proximal femur.