Effects of strontium ranelate on osseointegration of titanium implant in osteoporotic rats

Abstract

Previous studies have demonstrated the dual effects of strontium ranelate (SR) on osteoporotic and undisturbed bone. However, reports of its effect on titanium implant osseointegration in osteoporotic bodies were limited. This study was designed to investigate the effects of SR on osseointegration of titanium implant in ovariectomized rats. Twelve weeks after bilateral ovariectomy in female Sprague-Dawley rats, each animal received two titanium implants in the distal metaphysis of femur. All rats were then randomly divided into two groups: Control and SR (625 mg/kg/day). Twelve weeks after implantation, serum levels of osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP) 5b, implant osseointegration and peri-implant trabecular microarchitecture were analyzed by histomorphometry, micro-computerized tomography (micro-CT), and biomechanical test. Compared with control, SR treatment increased serum levels of OCN by 29.2%, and decreased the levels of TRAP 5b by 25.5% in serum analysis; SR treatment increased percent bone volume by 63.1% and percent osseointegration by 48.3% in micro-CT assessment, and increased bone area density by 55.6% and bone-to-implant contact by 49.0% in histomorphometry; SR treatment also increased the maximal push-out force by 117.7% and the ultimate shear strength by 103.5% in push-out test. Strontium ranelate treatment could improve titanium implant osseointegration in osteoporotic rats.