(A-C) Group 1 (0%WPC); (D-F) Group 2 (15%WPC); (G-I) Group 3 (20%WPC); (J-L) Group
4 (30%WPC); (M-O) Group 5 (50%WPC). At 15 days, a chronic inflammatory infiltrate,
moderate with predominance of macrophage (black arrow) is observed, presence of
giant multinuclear cell (red arrow), areas with Portland cement particles involved
with giant cells (black circle) and a mild presence of fiber connective tissue
(asterisk) in all groups. At 30 days, a decrease in the inflammatory infiltrate
and a discrete increase in fiber connective tissue (asterisk) in comparison with
the 15 days period were observed. Futhermore, at 30 days the presence of
macrophage cells (black arrow) is predominant. Areas with Portland cement
particles involved with giant cells are still present in this period (black
circle). At 60 days, the chronic inflammatory response is mild with isolated
macrophage-like cell (black arrow) and giant cells (red arrow). The presence of
fiber connective tissue related to the repair process is evident (asterisk)