Fluorhydroxyapatite Coatings Obtained by Flame-Spraying Deposition

Medical‐grade hydroxyapatite has been used in different forms and has been applied in different ways. To improve the thermal properties of hydroxyapatites, samples with precise fluoride content were prepared (fluorhydroxyapatites) to avoid the toxic effect of the higher amount of fluoride in the organism. Plasma spraying is the most common of all the application techniques used in the coating processes of hydroxyapatite, even though the partial decomposition of hydroxyapatite was reported. To avoid this inconvenience, another method was used for coating: flame spraying. This technology is a novelty regarding the fluorhydroxyapatite coatings on metallic surfaces. Its positive results present a new, cheap, and efficient possibility for fluorhydroxiapatite coatings on metallic implants. The stabilizing effect of fluoride was confirmed by the results obtained for the coating characterization, which shows the presence of a single phase: fluorhydroxyapatite.