Postmenopausal osteoporosis and poor dietary habits can lead to overweightness and obesity. Bisphosphonates are the first-line treatment for osteoporosis. However, some studies show that they may increase the risk of osteonecrosis of the jaw. Considering the antimicrobial, angiogenic and vasodilatory potential of nitric oxide, this study aims to evaluate the local activity of this substance during the placement of surface-treated implants. Seventy-two Wistar rats were divided into three groups: SHAM (SHAM surgery), OVX + HD (ovariectomy + cafeteria diet), and OVX + HD + RIS (ovariectomy + cafeteria diet + sodium risedronate treatment), which were further subdivided according to the surface treatment of the future implant: CONV (conventional), TE10, or TE100 (TERPY at 10 or 100 μM concentration); n = 8 per subgroup. The animals underwent surgery for implant installation in the proximal tibia metaphysis and were euthanized after 28 days. Data obtained from removal torque and RT-PCR (OPG, RANKL, ALP, IBSP and VEGF expression) were subjected to statistical analysis at 5% significance level. For biomechanical analysis, TE10 produced better results in the OVX + HD group (7.4 N/cm, SD = 0.6819). Molecular analysis showed: (1) significant increase in OPG gene expression in OVX groups with TE10; (2) decreased RANKL expression in OVX + HD + RIS compared to OVX + HD; (3) significantly increased expressions of IBSP and VEGF for OVX + HD + RIS TE10. At its lowest concentration, TERPY has the potential to improve peri-implant conditions.

Bisphosphonates are widely used for the treatment of postmenopausal osteoporosis; however, they cause several long-term side effects, necessitating the investigation of local ways to improve osseointegration in compromised bone tissue. The purpose of this study was to evaluate peri-implant bone repair using implants functionalized with zoledronic acid alone (OVX ZOL group, n = 11), zoledronic acid + teriparatide (OVX ZOL + TERI group, n = 11), and zoledronic acid + ruterpy (OVX ZOL + TERPY group, n = 11) compared to the control group (OVX CONV, n = 11). Analyses included computer-assisted microtomography, qualitative histologic analysis, and real-time PCR analysis. Histologically, all functionalized surfaces improved peri-implant repair, with the OVX ZOL + TERI group standing out. Similar results were found in computerized microtomography analysis. In real-time PCR analysis, however, the OVX ZOL and OVX ZOL + TERPY groups showed better results for bone formation, with the OVX ZOL + TERPY group standing out, while there were no statistical differences between the OVX CONV and OVX ZOL + TERI groups for the genes studied at 28 postoperative days. Nevertheless, all functionalized groups showed a reduced rate of bone resorption. In short, all surface functionalization groups outperformed the control group, with overall better results for the OVX ZOL + TERI group.

Osteoporosis compromises bone quality and impairs implant osseointegration. Since an adequate bone bed is essential for implant stability and success, this study evaluated the effects of implant surface functionalization with zoledronic acid (ZOL), alone or combined with ruterpy (TERPY), on peri-implant bone healing in healthy (SHAM) and osteoporotic (OVX) rats. ZOL has antiresorptive properties, while TERPY exhibits osteoinductive potential. The hypothesis was that ZOL + TERPY would act synergistically by inhibiting bone resorption and promoting new bone formation. Sixty-six female Wistar rats (3 months old) were divided into six groups (n = 11) according to systemic condition (SHAM or OVX) and implant type: conventional (CONV), ZOL, or ZOL + TERPY. Surgeries (sham or bilateral ovariectomy) were performed on day 0, and implants were placed in the tibial metaphysis on day 90. Fluorochromes were administered on days 104 (calcein) and 114 (alizarin), and euthanasia was performed on day 118. Samples were analyzed histologically via confocal microscopy and micro-computed tomography (Micro-CT). The ZOL + TERPY groups demonstrated significantly accelerated peri-implant bone repair, showing greater bone formation and organization; improved BV/TV, Tb.N, and I.S.; and reduced Tb.Sp and Po.Tot compared to CONV and ZOL-alone groups. In conclusion, ZOL + TERPY enhances and speeds bone healing, even under osteoporotic conditions.