*2.2. In Vitro Tests*

## 2.2.1. Static Surface Wettability

Heparinized sheep blood was filled in a dish 3.5 cm in diameter to a depth of 2 to 3 cm. Implant fixtures of SA + VUV and SA + VUV + BS (*n* = 5, respectively) were immersed in blood up to the uppermost discontinuation of apical threads, and the time to reach the top of the implant fixture was recorded to calculate the wetting velocity. The time was not counted from the apex of the implant fixture, because the presence of discontinuation of apical threads caused blood absorption to stop abruptly.

## 2.2.2. Dynamic Surface Wettability

To simulate the clinical situations of implant fixture installation, holes were made in a transparent acrylic plate to secure visibility, according to the manufacturer's drilling protocol for hard bone density using a 122 Taper Kit (Osstem). A 130 μM sample of defibrinated sheep blood was placed into each hole of the acrylic plate, and the implant fixtures of SA + VUV and SA + VUV + BS (*n* = 5, respectively) were dipped into the hole by a push–pull gauge (MX-500N, Imada Co., Tokyo, Japan) at a speed of 50 mm/min, and the times when the blood reached up to the 2 mm and 4 mm points of the central axis of the fixture above the horizontal plate, respectively, were recorded (Figure 2).

**Figure 2.** In vitro test of dynamic surface wettability: (**a**) a transparent acrylic plate with implant holes and the implant fixture in a push–pull gauge; (**b**) baseline, contact of the implant fixture with the blood, and whole insertion of implant fixture into the hole.
