Low-magnitude high-frequency loading via whole body vibration enhances bone-implant osseointegration in ovariectomized rats

Osseointegration is vital to avoid long‐time implants loosening after implantation surgery. This study investigated the effect of low‐magnitude high‐frequency (LMHF) loading via whole body vibration on bone‐implant osseointegration in osteoporotic rats, and a comparison was made between LMHF vibration and alendronate on their effects. Thirty rats were ovariectomized to induce osteoporosis, and then treated with LMHF vibration (VIB) or alendronate (ALN) or a control treatment (OVX). Another 10 rats underwent sham operation to establish Sham control group. Prior to treatment, hydroxyapatite (HA)‐coated titanium implants were inserted into proximal tibiae bilaterally. Both LMHF vibration and alendronate treatment lasted for 8 weeks. Histomorphometrical assess showed that both group VIB, ALN and Sham significantly increased bone‐to‐implant contact and peri‐implant bone fraction (p < 0.05) when compared with group OVX. Nevertheless the bone‐to‐implant contact and peri‐implant bone fraction of group VIB were inferior to group ALN and Sham (p < 0.05). Biomechanical tests also revealed similar results in maximum push out force and interfacial shear strength. Accordingly, it is concluded that LMHF loading via whole body vibration enhances bone‐to‐implant osseointegration in ovariectomized rats, but its effectiveness is weaker than alendronate. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:733–739, 2012