Surface modification of Ti6Al4V screws Using HA-mixed EDCLT for applications of dental implants

Titanium alloy is the most usable alloy for dental implant applications. Surface properties play a vital role in enhancing the bone integration of titanium alloy dental implants. This study is about the surface modification of Ti6Al4V screw implants using hydroxyapatite-mixed electric discharge-assisted centreless turning (HA-mixed EDCLT). Experiments were planned based on the Box–Behnken design. Surface roughness (Ra), hardness (HV), and material removal rate (MRR) were the output, and impulse current (IP), duty factor, revolutions per minute (RPM), and powder concentration (Cp) were the input variables. The impulse current shows the maximum percentage contribution for MRR followed by duty factor, Cp, and RPM. Surface roughness is in the range of 0.310–1.899 µm, demonstrating that it is suitable for metal implant applications. The average hardness reached from 345 to 858 HV, higher than the untreated surfaces' hardness (340 ± 4 HV). The research shows that rougher surfaces tend to have a minor wetting ability in the 0.310–1.899 µm range. The modified surface layer is rich with carbide and oxide content, showing inertness with the surrounding environment and enhancing the corrosion properties. XRD and FTIR studies indicated that the deposited layer in the HA-mixed EDCLT was HA, which improved the implants' biocompatibility. Ca₁₀(OH)₂(PO₄)₆, Ca₁₀(PO₄)₃(C O₃)₃(OH) and TiO₂ compounds found on the processed surfaces. It improved the bioactivity of the alloy and was beneficial for promoting osseointegration.