Figure 1. AFM tapping-mode images of FAP glass-ceramic substrates: (a) hexagonal (001)- planes of FAP after being polished and before the experiment; (b) sectional view, revealing 5-nm step height between glass and FAP; (c) substrate after 1 hr of immersion in 0.4 mg/mL rH174, showing nanospheres adhering to glass and FAP; (d) substrate after 24-hour immersion in 0.4 mg/mL rH174, showing that amelogenin nanospheres with diameters around 25 nm formed dense layers; (e) substrate after 24-hour immersion in 1.6 mg/mL rH174, revealing larger spherical aggregates of about 150 nm; and (f) characteristic amelogenin nanospheres (20 nm) are absent on glass (shown in image) and FAP at 1.6 mg/mL rH174 concentration.