3.3.1. ALP Activity

ALP activities of MG-63 cells seeded on the surface of Ti, PDGF/Hepa/Ti, BMP/Hepa/Ti, and PDGF/BMP/Hepa/Ti discs were confirmed after 3, 7, and 10 days of culture (Figure 5a). On day 3, the ALP activities of cells cultured on PDGF/Hepa/Ti, BMP/Hepa/Ti, and PDGF/BMP/Hepa/Ti were higher than that of cells cultured on Ti. On days 7 and 10, the ALP activities of cells that are grown on PDGF/Hepa/Ti, BMP/Hepa/Ti, and PDGF/BMP/Hepa/Ti differed significantly from those grown on Ti alone. On days 7 and 10, the ALP activity of cells cultivated on BMP/Hepa/Ti was significantly higher than that of those cultyivated on PDGF/Hepa/Ti or PDGF/BMP/Hepa/Ti.

**Figure 5.** (**a**) Alkaline phosphatase (ALP) activities of cells cultured on Ti, PDGF/Hepa/Ti, BMP/Hepa/Ti, and PDGF/BMP/Hepa/Ti for 3, 7, or 10 days (\* *p* < 0.05 and \*\* *p* < 0.01); (**b**) Calcium contents of cells grown on Ti, PDGF/Hepa/Ti, BMP/Hepa/Ti, and PDGF/BMP/Hepa/Ti for 7 or 21 days (\* *p* < 0.05 and \*\* *p* < 0.01).

#### 3.3.2. Calcium Contents

The calcium contents of MG-63 cells cultured on Ti, PDGF/Hepa/Ti, BMP/Hepa/Ti, and PDGF/BMP/Hepa/Ti discs for 7 and 21 days are shown in Figure 4. The calcium contents of cells cultivated on PDGF/Hepa/Ti, BMP/Hepa/Ti, and PDGF/BMP/Hepa/Ti were significantly greater than that those that were grown on Ti alone on days 7 and 21. Moreover, the calcium contents of

cells grown on BMP/Hepa/Ti and PDGF/Hepa/Ti and on BMP/Hepa/Ti and PDGF/BMP/Hepa/Ti differed significantly.
