Synthesis of hydroxyapatite nanocomposite coating by electrodeposition route: a state of the art review

Hydroxyapatite (HA) is widely employed as a coating on implants due to its biocompatibility. Deposition techniques for HA include sol-gel, sputter coating, vacuum deposition, plasma spraying, hot isostatic pressing, biomimetic deposition, pulsed laser deposition, electrophoretic deposition (EPD), and electrodeposition. Among these, electrodeposition is preferred for its ability to form consistent crystals at low temperatures with minimal stress. However, pure HA coatings often suffer from low bonding strength, limiting mechanical performance. To overcome this, reinforcements, such as metals, polymers, and ceramics, are incorporated to enhance mechanical strength, bioactivity, and antibacterial properties. Researchers have reported that ceramic reinforcements like TiO2 and ZrO2 at concentrations of 3 and 6 mM/L improve HA's mechanical and bioactive properties. Polymer-reinforced composites, such as those with multiwalled carbon nanotubes (MWCNTs), enhance osteoconduction, cytocompatibility, and corrosion resistance, improving implant performance. Metallic reinforcements like Ag and Zn add antibacterial properties, reducing post-implantation infections. These reinforcements collectively address the limitations of pure HA coatings, offering a multifunctional solution for implant applications. This review focuses on the electrodeposition of reinforced HA nanocomposite coatings, emphasising the role of ceramic, polymer, and metallic reinforcements in improving the mechanical, biological, and antibacterial performance of implants, making them effective in biomedical applications. L'hydroxyapatite (HA) est largement utilis & eacute;e comme rev & ecirc;tement sur les implants en raison de son excellente biocompatibilit & eacute;. Diverses techniques de d & eacute;p & ocirc;t d'HA comprennent le sol-gel, le rev & ecirc;tement par pulv & eacute;risation, le d & eacute;p & ocirc;t sous vide, la projection au plasma, le pressage isostatique & agrave; chaud, le d & eacute;p & ocirc;t biomim & eacute;tique, le d & eacute;p & ocirc;t par laser & agrave; impulsions, le d & eacute;p & ocirc;t par & eacute;lectrophor & egrave;se (EPD) et l'& eacute;lectrod & eacute;position. Parmi celles-ci, l'& eacute;lectrod & eacute;position attire l'attention comme une m & eacute;thode attrayante car elle permet une formation constante de cristaux & agrave; basse temp & eacute;rature ou & agrave; temp & eacute;rature ambiante, avec une contrainte r & eacute;siduelle minimale. Cependant, les rev & ecirc;tements de HA purs sur les surfaces m & eacute;talliques souffrent souvent d'une faible force de liaison, limitant leurs performances m & eacute;caniques. Pour r & eacute;soudre ce probl & egrave;me, on utilise couramment des mat & eacute;riaux tels que des m & eacute;taux, des polym & egrave;res et des c & eacute;ramiques comme renforts pour am & eacute;liorer la r & eacute;sistance m & eacute;canique, la bioactivit & eacute; et les propri & eacute;t & eacute;s antibact & eacute;riennes des rev & ecirc;tements de HA. Les chercheurs ont rapport & eacute; que les renforts c & eacute;ramiques tels que TiO2 et ZrO2 & agrave; des concentrations de 3 et 6 mM/L am & eacute;liorent significativement les propri & eacute;t & eacute;s m & eacute;caniques et bioactives de la matrice de HA. En plus, les rev & ecirc;tements composites polym & egrave;res renforc & eacute;s de nanotubes de carbone & agrave; parois multiples (MWCNT) augmentent l'ost & eacute;oconduction, la cytocompatibilit & eacute; et la r & eacute;sistance & agrave; la corrosion, am & eacute;liorant ainsi les performances globales des implants m & eacute;talliques. Les renforts m & eacute;talliques, tels que Ag et Zn, conf & egrave;rent des propri & eacute;t & eacute;s antibact & eacute;riennes, aidant & agrave; pr & eacute;venir les infections apr & egrave;s implantation. En r & eacute;sum & eacute;, cet article passe en revue le d & eacute;p & ocirc;t de rev & ecirc;tements nanocomposites de HA renforc & eacute;s sur les implants m & eacute;talliques utilisant des techniques d'& eacute;lectrod & eacute;position, mettant en lumi & egrave;re les avantages potentiels de l'incorporation de divers renforts pour am & eacute;liorer les performances d'implants en termes de propri & eacute;t & eacute;s m & eacute;caniques, biologiques et antibact & eacute;riennes.