Abstract
BackgroundHydroxyapatite (HA) coatings composed with bisphosphonates (BPs) which have high mineral-binding affinities have been confirmed to successfully enhance implant stability. However, few previous studies focused on HA coatings composed with low-affinity BPs or on systemic effects of locally released BPs.MethodsIn this long-term study, we developed two kinds of BP-HA composite coatings using either high-affinity BP (alendronate, ALN) or low-affinity BP (risedronate, RIS). Thirty-six rabbits were divided into three groups according to different coating applications (group I: HA, group II: ALN-HA, and group III: RIS-HA). Implants were inserted into the proximal region of the medullary cavity of the left tibiay. At insertion, 2 × 108 wear particles were injected around implants to induce a peri-implant high bone turnover environment. Both local (left tibias) and systemic (right tibias and lumbar vertebrae) inhibitory effect on bone resorption were compared, including bone-implant integration, bone architecture, bone mineral density (BMD), implant stability, and serum levels of bone turnover markers.ResultsThe results indicated that ALN-HA composite coating, which could induce higher bone-implant contact (BIC) ratio, bone mass augmentation, BMD, and implant stability in the peri-implant region, was more potent on peri-implant bone, while RIS-HA composite coating, which had significant systemic effect, was more potent on non-peri-implant bone, especially lumbar vertebrae.ConclusionsIt is instructive and meaningful to further clinical studies that we could choose different BP-HA composite coatings according to the patient’s condition.
Highlights
Hydroxyapatite (HA) coatings composed with bisphosphonates (BPs) which have high mineralbinding affinities have been confirmed to successfully enhance implant stability
The anti-resorptive potency is mainly influenced by R2 side-chain, and the rank order is: ZOL > RIS > ibandronate > ALN > pamidronate, which closely matches the order of potency on inhibiting farnesyl pyrophosphate synthase (FPPS) [3,8,9,10]
At week 24, ALN (BIC = 51.82 ± 7.09%) showed stronger osteo-integrating effect compared to RIS (BIC = 41.46 ± 9.15%, p < 0.05)
Summary
Hydroxyapatite (HA) coatings composed with bisphosphonates (BPs) which have high mineralbinding affinities have been confirmed to successfully enhance implant stability. Considerable studies have focused on preventing aseptic loosening and enhancing implant stability in revision. BPs have a P-C-P structure and two side-chains (R1 and R2) Their mineral-binding affinities are mainly influenced by R1 side-chain. Nancollas et al [7] established a rank order of their mineral- binding affinities: zoledronate (ZOL) > ALN > ibandronate > RIS > etidronate > clodronate. The anti-resorptive potency is mainly influenced by R2 side-chain, and the rank order is: ZOL > RIS > ibandronate > ALN > pamidronate, which closely matches the order of potency on inhibiting farnesyl pyrophosphate synthase (FPPS) [3,8,9,10]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
