Aim: The objectives of this study were three: 1) obtaining electronic microscopy images before and after a PRF pretreatment from three different implant surfaces, 2) evaluating the angle contact obtained wetting, with a blood drop, three different implant surfaces and 3) evaluating if the PRF pretreatment of the same implant surfaces, modifies their wettability. Methods: Six implant surface\u2019s samples were selected: two machined, two blasted and two with laser treatment. Four images for implant surface were acquired by SEM (Scanning Electron Microscope) before and after a PRF pretreatment, respectively with 200x, 500x, 1000x and 2000x magnification. Afterwards the angle contact formed between three different implant surfaces and 10\u3bcl blood drop was calculated by optical microscope with 10x magnification. With other three samples, that were pretreated with PRF, the angle contact formed between the different implant surfaces and 10\u3bcl blood drop was evaluated by the same microscope. The pretreatment of the implant surfaces was made soaking the samples in the PRF and after drying them with sterile gauze. The entire procedure was performed five times in five different days to obtain five measurements for implant surface with and without the PRF pretreatment. The human blood, for the drops and for the PRF production, was drawn from the same volunteer for all the time.
Results: The results obtained with SEM were poorly relevant. It was possible to observe only a few fibrin deposits on implant surfaces with PRF pretreatment. The results obtained with optical microscopy, evaluating different surfaces between them, were relevant: by using \u201cnon parametric\u201d tests with software SPSS for Mac OS X (SPSS inc. Chicago, IL, USA) a significant wettability difference from different implant surfaces was observed. The average angle contact of the different surfaces were: for the machined surface 56.58 \ub1 12.83, for the sandblasted surface 76.45 \ub1 6.93 and for laser treated surface 51.02 \ub1 3.49. The results obtained, calculating the angle contact after PRF pretreatment of implant surfaces, were very interesting and satisfying. It was possible to observe an important wettability improvement of implant surfaces: machined surface had 33.67 \ub1 3.06, sandblasted surface had 38.84 \ub1 8.49 and laser treated surface had 32.88 \ub1 1.59. The statistical analysis highlighted a significant wettability difference from the same implant surface before and after PRF pretreatment but there was not significant angle contact difference between the different surfaces after PRF pretreatment; in fact the angle contact values were very similar Conclusions: Compelling evidence from our study lead us to suggest, according to scientific literature, that the machined surfaces have more wettability than sandblasted surfaces and a similar one compare to the laser treated surfaces. The PRF pretreatment have a positive effect on wettability of implant surfaces. This effect is independent from the kind of surface, probably because the wettability improvement is directly related to PRF proprieties and not to the characteristics of the implant surface even if the results with SEM were not significant; perhaps due to chemical changes on implant surfaces (not visible by microscopy) thanks to PRF pretreatment. So the PRF could be used as a helper to make the osseointegration process faster by using a rough surface, which stimulates the cell differentiation, with an optimal wettability, which allows to improve the cell adhesion
