Enhancement of Osseointegration of Bio-Active Material Surface by the Low-Intensive Pulsed Ultrasound Waving (LIPUS)

Abstract

Excellent firm bonding between the biomaterials and bone tissue (osseointegration and osteo-conductivity) is very important for the stability of dental implants and artificial joints etc. Much has been learned about this concept, which has led to significant improvements in the design and surface modification of implants in the field of implant dentistry, orthopedic surgery. For this issue, we have focused on the effects of low-intensity pulsed ultrasound (LIPUS) irradiation, investigated whether LIPUS could accelerate the osseointegration ability of bio-active material such as bioactive titanium and hydroxyapatite. As samples, Bio-active pure titanium and hydroxyapatite (HA) were prepared, in vitro  simulation test and animal  experiment have performed. In simulation test, the bone-like hydroxyapatite formation on material surface in simulated  body fluid (SBF) under the LIPUS were assessed. In animal test, the  bio-active samples implanted to the rabbits  femur, undertaken the irradiation of LIPUS were investigated by using Scanning Electron Microscope (SEM), X-ray diffraction (XRD) etc. and histological observation. As a result, LIPUS irradiation showed the excellent enhancement of bone-material attachment by means of the crystal growth of bone-like apatite on sample materials surface, which suggested the application of LIPUS has  clinical potential to improve the osseointegration (osteointegration), bone-bonding  ability of  bio-active materials.