Serum bone formation marker correlation with improved osseointegration in osteoporotic rats treated with simvastatin.

Simvastatin has been shown to enhance osseointegration of pure titanium implants in osteoporotic rats. This study aimed to evaluate the relationship between the serum level of bone formation markers and the osseointegration of pure titanium implants in osteoporotic rats treated with simvastatin. Fifty-four female Sprague-Dawley rats, aged 3 months, were randomly divided into three groups: Sham-operated group (SHAM; n = 18), ovariectomized group (OVX; n = 18), and ovariectomized with simvastatin treatment group (OVX + SIM; n = 18). Fifty-six days after ovariectomy, screw-shaped titanium implants were inserted into the tibiae. Simvastatin was administered orally at 5 mg/kg each day after the placement of the implant in the OVX + SIM group. The animals were killed at either 28 or 84 days after implantation and the undecalcified tissue sections were processed for histological analysis. Total alkaline phosphatase (ALP), bone-specific alkaline phosphatase (BALP) and bone Gla protein (BGP) were measured in all animal sera collected at the time of euthanasia and correlated with the histological assessment of osseointegration. The level of ALP in the OVX group was higher than the SHAM group at day 28, with no differences between the three groups at day 84. The level of BALP in the OVX + SIM group was significantly higher than both OVX and SHAM groups at days 28. Compared with day 28, the BALP level of all three groups showed a significant decrease at day 84. There were no significant differences in BGP levels between the three groups at day 28, but at day 84, the OVX + SIM group showed significantly higher levels than both the OVX and SHAM groups. There was a significant increase in BGP levels between days 28 and 84 in the OVX + SIM group. The serum bone marker levels correlated with the histological assessment showing reduced osseointegration in the OVX compared to the SHAM group which is subsequently reversed in the OVX + SIM group. The results from this study indicate that the serum level of bone formation markers, especially BALP and BGP, could be correlated with the degree of osseointegration around titanium implants in osteoporotic rats treated with simvastatin.

Du Z ，Chen J ，Yan F ，Doan N ，Ivanovski S ，Xiao Y ... -  《-》

Effects of Simvastatin on bone healing around titanium implants in osteoporotic rats.

Du Z ，Chen J ，Yan F ，Xiao Y ... -  《-》

The effects of combined human parathyroid hormone (1-34) and simvastatin treatment on osseous integration of hydroxyapatite-coated titanium implants in the femur of ovariectomized rats.

The effect of human parathyroid hormone 1-34 (PTH) and simvastatin (SIM) alone could promote bone healing in osteoporotic osseous integration of the implant, but there are no reports about the combined use of PTH and SIM for promotion of bone healing around implant in osteoporotic settings still limited. This study aims to investigate effects of PTH+SIM on osseous integration of the implant in OVX rats. Female Sprague-Dawley rats were used for this study. Twelve weeks after bilateral ovariectomy, all animals were randomly divided into four groups: group control; group SIM; group PTH and group PTH+SIM. Afterwards, all OVX rats received hydroxyapatite (HA)-coated titanium rods (external diameter and length are 1.5mm and 20mm) in the femoral medullary canal. Subsequently, the animals from group SIM, group PTH and group PTH+SIM received human parathyroid hormone 1-34 (60μg/kg, three times a week), SIM (5mg/kg daily), or both for 12 weeks. Implants were inserted bilaterally in all animals until death at 12 weeks. The bilateral femurs of rats were harvested for evaluation. All groups increased new bone formation around the surface of titanium rods and push-out force; group PTH+SIM showed the strongest effects on new bone formation and biomechanical strength. Additionally, these are significant difference observed in bone formation and push-out force between groups SIM and PTH. This finding suggests that intermittent administration of PTH or SIM alone has an effect to increase new bone formation on the surface of HA-coated implants in the osteoporotic condition, and the additive effects of combination PTH and SIM on osseous integration of the implant in OVX rats.

Tao ZS ，Zhou WS ，Tu KK ，Huang ZL ，Zhou Q ，Sun T ，Lv YX ，Cui W ，Yang L ... -  《-》

Biological Response to Recombinant Human Bone Morphogenetic Protein-2 on Bone-Implant Osseointegration in Ovariectomized Experimental Design.

Song Y ，Wan L ，Zhang S ，Du Y ... -  《-》

Effect of zoledronic acid on osseointegration of titanium implants: an experimental study in an ovariectomized rabbit model.

Zoledronic acid (ZA), a new-generation intravenous bisphosphonate, exhibits the greatest affinity for bone mineral with the longest retention, thereby leading to its ability to be dosed at annual intervals in the treatment of osteoporosis. The purpose of this preliminary study was to evaluate the effects of systemic administration of a single dose of ZA on osseointegration and bone healing around titanium dental implants. Thirty-six female New Zealand rabbits (aged 6-12 months) were used in this study. Rabbits were randomly assigned to 1 of 3 groups: sham control group (SH), ovariectomy group (OVX), and OVX and ZA group (OVX + ZA). Animals in the OVX and OVX + ZA groups were subjected to bilateral ovariectomy, whereas animals in the SH group were sham operated. Eight weeks later, 1 implant was placed in each tibia of the animals. ZA was administered in the OVX + ZA group during the implantation, whereas the OVX and SH groups received saline solution infusions. All of the subjects were sacrificed 8 weeks after the implantation, and tibial specimens were harvested. Histomorphometric bone-to-implant contact analysis, resonance frequency analysis, removal torque testing, and digital radiographic absorptiometry were administered, and the data were statistically analyzed. Histomorphometric, resonance frequency, and radiodensitometric analyses showed significant improvement in osseointegration of implants in the OVX + ZA group compared with the OVX group. However, the differences in removal torque results between the groups were not statistically significant. The results of this study suggest that systemic ZA administration may improve osseointegration of titanium implants placed in estrogen-deficient states of bone.

Yildiz A ，Esen E ，Kürkçü M ，Damlar I ，Dağlioğlu K ，Akova T ... -  《-》