The Efficiency of Fluoride Bioactive Glasses in Protecting Enamel Surrounding Orthodontic Bracket

Figure 4

SEM observation for the top view of the specimens. Low magnification (a) and high magnification (b) top surface view for the control group (before erosion challenge) showing smooth enamel surface next to the orthodontic bracket. (c) High magnification for the control group (after erosion challenge) showing rough enamel surface with obvious boundaries of the enamel prisms. Low (d) and high (e) magnification for the FBG1 group (before erosion challenge) showing crystalline structures covering the areas next to the orthodontic bracket. (f) High magnification for the FBG1 group (after erosion challenge) showing resistance of the formed layer to erosion challenge. Low (g) and high (h) magnification for the FBG2 group (before erosion challenge) showing crystalline structures covering the areas next to the orthodontic bracket. (i) High magnification for the FBG2 group (after erosion challenge) showing resistance of the formed layer to erosion challenge. Low (j) and high (k) magnification for the FBG3 group (before erosion challenge) showing crystalline structures covering the areas next to the orthodontic bracket. (l) High magnification for the FBG3 group (after erosion challenge) showing resistance of the formed layer to erosion challenge. Low (m) and high (n) magnification for the FBG4 group (before erosion challenge) showing crystalline structures covering the areas next to the orthodontic bracket. (o) High magnification for the FBG4 group (after erosion challenge) showing resistance of the formed layer to erosion challenge.

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

(i)

(j)

(k)

(l)

(m)

(n)

(o)