ROLE OF 'BISPHOSPHONATES' IN PROSTHODONTICS- A REVIEW.

ABSTRACT

Bisphosphonates (BPs), particularly nitrogen-containing variants (N-BPs) such as zoledronate, alendronate, ibandronate, pamidronate, and risedronate, represent a promising class of bioactive agents for functionalizing implant surface coatings to enhance osseointegration in dental and orthopedic applications.  These coatings allow for localized drug delivery. They directly stop osteoclast-mediated bone resorption by breaking the mevalonate pathway and farnesyl pyrophosphate synthase. They also encourage osteoblast proliferation and differentiation by increasing the activity of osteogenic genes (like BMP-2 and Runx2) and pathways like ERK/JNK.  Common materials used for sustained release are titanium dioxide nanotubes (TNTs), hydroxyapatite (HA), mesoporous silica, and organic polymers (like chitosan and PLGA). These materials are used in ways like physical adsorption, covalent grafting, or porous carrier encapsulation.  Preclinical studies in sheep and ovariectomized rat models show that zoledronate-coated implants have better early mechanical stability (for example, higher removal torque at 10 days) and more bone-to-implant contact than uncoated controls, with no signs of necrosis.  Nonetheless, advantages may be transient (declining by 28 days), and systemic BP application is associated with a 49.96% implant failure rate, which can be reduced by local coatings that prevent these risks.  Problems include dose-dependent cytotoxicity at high concentrations (>10^{-4} M) and a lack of long-term clinical data.  Future directions focus on hybrid multifunctional coatings that combine N-BPs with growth factors or antimicrobials for personalized, 3D-printed implants. This could change the way osteoporotic patients do things.

Keywords: Bisphosphonates (BP); Nitrogen-containing bisphosphonates; Implant surface coatings; Osseointegration; Dental implants; Zoledronate; Osteoclast inhibition.