Pulp exposure model in mice. (A) Bright-field image of cryosections of mouse lower first molar: control and pulp exposure model at 2 and 4 days after injury. (B,C) Immunofluorescence staining for CD146. Note a strong signal intensity corresponding to CD146 at 2 days after pulp exposure. (D) Hematoxylin and eosin staining of sections. Dotted lines indicate the drilled dentin with clear pulp exposure, arrows show cellular debris, and squares indicate the area shown at high magnification in (C). Arrowheads indicate CD146+ cells. d, dentin; p, dental pulp. Scale bars = 100 μm (A,B) and 50 μm (C,D). Images are representative of three independent samples.