**4. Conclusions**

The results revealed that, after 24 h of incubation, only the surfaces with Ag gave rise to the appearance of an inhibition growth halo, which was bigger in HA/Ag than for HA/F/Ag, 2.6 and 1.4 mm, respectively. The absence of inhibition halo around the samples with fluorine (HA/F) was surprising as this element is cited as an antibacterial agent. The surfaces were

**Figure 8.** SEM micrographs of the surface of the produced coatings after 24 h of contact with *Staphylococcus epidermidis.*

then observed by scanning electron microscopy (SEM) (**Figure 8**).

76 Nanocomposites - Recent Evolutions

**Figure 7.** Release of fluorine from HA/F (blue) and HA/F/Ag (red).

Sputtering is a very versatile technology for the production of hybrid nanocomposite thin films. The ability to develop materials that are not predicted by conventional thermodynamics inheres this technology as one of the best for the development of tailor-made surfaces. In this chapter, it has been highlighted this capacity by describing HA-based hybrid nanocomposites that can be designed to increase the osseointegration of metallic materials usually used for implants with contact with biological hard tissue. The HA-based nanocomposites hybrid coatings were also chosen to demonstrate the capacity of developing hybrid ceramic/polymer/metal nanocomposites with good antibacterial activity. The combination of these three types of materials in one surface is almost impossible to obtain, except by the use of the sputtering technique.
