Table 6.

Results of Hydroxyapatite coating on PEEK.

Treatment	Result	Author
Surface coatings—Hydroxyapatite
Hydroxyapatite	In vivo: Increased removal torque and biocompatibility	Johansson et al. [73]
[Hydroxyapatite/(Hydroxyapatite + Microwave annealing)] + YSZ intermediate layer	In vitro: Increased cell adhesion and proliferation with Hydroxyapatite crystallization with microwave annealing	Rabiei et al. [71]
Hydroxyapatite + Titanium intermediate layer + Hydrothermal treatment	In vitro: Bond strength of HA with PEEK with <10 nm Ti layer greater than that with >50 nm Ti layer	Ozeki et al. [72]
[Hydroxyapatite/(Hydroxyapatite + Microwave annealing + Autoclaving)] + YSZ intermediate layer	In vitro: Increased cell adhesion and proliferation with Hydroxyapatite crystallization with heat treatment	Durham et al. [70]