Fig. 2
From: Characterization of the apical bridge barrier formed following amelogenin apexification
Premolar teeth treated with RAP or CH at 3 months. a Sagittal image of the apical region of the root of a premolar tooth treated with CH at the end of 3 months showing complete apical bridging (AB) of the root apices by cellular hard tissue formed of dentin (D) and cellular cementum (CC). Granulation tissue (GT) surrounds the closed apex. Root canal (RC). Trichrome stain. Original magnification, X 100. b Apical region of a premolar tooth treated with CH after 3 months of healing showing apical bridging (AB) of the open apex by a thin and almost complete layer of cellular hard tissue and dentin (D) that shows no immuno-reactivity to Wnt10b antibody. Granulation tissue (GT) also shows no immuno-reactivity to Wnt10b antibody. Some mineralized tissue (arrow) can be seen in the root canal (RC). Wnt10b antibody. Original magnification, × 200. c Apical root area of a premolar tooth treated with CH after 3 months showing incomplete apical bridging (AB) that shows immuno-reactivity to nestin antibody. Dentin-associated mineralized tissue (DAMT) (box). Odontoblast cells (arrow) and newly deposited dentin and DAMT show immuno-reactivity to the nestin antibody. Granulation tissue observed at a distance from the root apex (GT) also shows moderate nestin immuno-reactivity. Original magnification, × 100. d Apical area of a premolar tooth treated with RAP after 3 months showing apical closure achieved by tertiary dentin showing incremental lines (arrows). Periodontal ligament (PDL), bone (B), cementum (C) and root canal (RC). Trichrome stain. Original magnification, × 100. e Apical root area of a tooth treated with RAP after 3 months showing apical bridging (AB). Odontoblast cells (od). Some mineralized tissue (arrow) can be seen in the root canal (RC) and granulation tissue (GT) show intense immuno-reactivity to Wnt10b antibody Root canal (RC). Wnt10b antibody. Original magnification, × 200. f Apical root area of a premolar tooth treated with RAP after 3 months showing apical bridging (AB) that shows moderate to intense immuno-reactivity to the nestin antibody. Granulation tissue (GT) shows mild immuno-reactivity to nestin antibody. Root canal (RC). Nestin antibody Original magnification, × 100