Two hydroxyapatite-coated implants were retrieved after 12 months of loading because of a fracture of the abutments. The specimens were treated to obtain thin ground sections, and a microprobe chemical analysis was done under a scanning electron microscope equipped with an energy-dispersive x-ray analysis and cathodoluminescence system. Under light microscopy, close contact between the bone and...

in this investigation, fluor-hydroxyapatite (fha) film was deposited on a titanium substrate by sol-gel method. triethyl phosphite, ammonium fluoride and calcium nitrate in ethanol solutions were used respectively as p, f and ca precursors. typical apatite structures were obtained for all coatings after dipping and subsequent heat treatment at 550, 700 and 800 ºc, the coating layers were invest...

background: titanium (ti) implants are commonly coated with hydroxyapatite (ha). however, ha has some disadvantages such as brittleness, low tensile strength and fracture toughness. it is desirable to combine the excellent mechanical properties of zro2 and the chemical inertness of al2o3 with respect to the purpose of this project which was coating ti implants with ha-zro2-al2o3 to modify the s...

Nanocrystalline Zn-substituted hydroxyapatite coatings were deposited by radiofrequency magnetron sputtering on the surface of ultrafine-grained titanium substrates. Cross-section transmission electron microscopy provided information about the morphology and texture of the thin film while in-column energy dispersive X-ray analysis confirmed the presence of Zn in the coating. The Zn-substituted ...

This clinical report describes the microscopic analysis of a threaded hydroxyapatite-coated root-form implant retrieved from an 89-year-old subject after 10 months of service. The implant was never loaded and was removed because it was nonrestorable. Clinically, the buccal area of the implant was covered by soft tissue, whereas the palatal side was covered by bone. Light microscopic evaluation ...

Thermally processed hydroxyapatite coatings used on dental implants and hip prostheses for enhanced fixation may typically consist of a number of chemical and structural phases. These phases affect coating performance and tissue attachment. Hydroxyapatite was plasma sprayed to examine the phase evolution during processing. Coatings were examined with X-ray diffraction and elemental analysis. Re...

Thin films of titanium carbonitride (TiCN) were fabricated by DC magnetron sputtering on medical grade steel. The biocompatibility of the coating was further enhanced by growing hydroxyapatite crystals over the TiCN-coated substrates using biologically activated ammonia from synthetic urine. The coatings were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, scanning elec...

Magnesium has been recently recognized as a biodegradation metal for bone substitute application. In the present work, porous magnesium-zinc scaffolds were prepared by powder metallurgical process and nano hydroxyapatite (HAP) coating on the Mg-3Zn (wt.%) scaffold was prepared by pulse electrodeposition and alkali treatment processes to improve the corrosion resistance of scaffold. The results ...

The trabecular bone response to noncoated and fluorapatite (FA), hydroxyapatite (HA), and hydroxyapatite heat-treated (HAHT) plasma-sprayed coated implants was investigated in a goat animal model. Forty-eight cylindrical implants were inserted into the trabecular bone of the lateral and medial femoral condyles of twelve goats according to a split plot design. After an implantation period of twe...

Implant materials need to be highly biocompatible to avoid inflammation in clinical practice. Although biodegradable polymeric implants can eliminate the need for a second surgical intervention to remove the implant materials, they may produce acidic degradation products in vivo and cause non-bacterial inflammation. Here we show the strategy of "substrate-anchored and degradation-sensitive coat...