The effects of SOST on implant osseointegration in ovariectomy osteoporotic mice

Osteoporosis is a risk factor for implant fixation failure. The inhibition of sclerostin effectively improves bone formation and bone remodeling. Therefore, this study investigated whether SOST deficiency enhances the osseointegration of implants in a mouse model of osteoporosis induced by ovariectomy (OVX).

Osteoporosis was induced in female C57BL/6 and SOST deficient mice by OVX. Titanium implants were placed in the bilateral distal aspects of the femurs. Implants underwent sandblasting and acid-etching after which the structure, surface roughness and chemical components were investigated using scanning electron microscopy (SEM) and energy spectrum analyses. Undecalcified slices, μ-CT, histology analyses and mechanical tests were used to evaluate the osseointegration of implants. The results were compared using one-way ANOVA between four groups.

Sandblasting and acid-etching increased the roughness of the implants. OVX surgery reduced bone formation around the implants in both WT and SOST^-/- mice. However, implant osseointegration was significantly improved in the SOST^-/- OVX mice compared to the WT OVX mice.

Inhibition of the SOST gene improved implant fixation in the OVX osteoporotic mice, which suggests a strategy for enhancing implant osseointegration in clinical patients with osteoporosis.