Fig. 2.

Photomicrographs of pulp tissue response after three months, at low magnification (×40), H&E-stained sections showed complete dentin bridge formation at the exposure site for TF and NMP groups (2-a and 2-c, respectively). The newly formed dentin bridges were separated from the existing dentin by demarcation line. At higher magnification (×100), H&E-stained sections showed thicker tubular reparative dentin formation in TF group (2-b) while in NMP group (2-d), the reparative dentin had thinner structure and was atubular. A new layer of odontoblast-like cells as well as dilated and congested blood vessels were also seen beneath the dentin bridge. The symbols in the histological sections indicate the following: (#) floor of the prepared cavity; (M) particles of pulp capping material; (RP) reparative dentin; (RA) reactionary dentin; (OLC) odontoblast-like cells; (N) necrosis; (arrows) dilated and congested blood vessels; (PS) pulp stone; (DL) demarcation line; (*) fibrosis; (D) dentin; (P) pulp.