Figure 1.

Focused ion beam images of the onset of dentin mineralization near ameloblasts in a wild‐type mouse mandibular incisor. Top: Low magnification montage of an incisor cross sectioned at Level 1 (~1 mm from its basal end). The box outlines the region detailed by higher magnification images shown below. Banded collagen fibers butt into ameloblasts at nearly right angles. Some ameloblast processes run along the sides of collagen fibers. Key: Am, ameloblast; arrowheads, calcification nodules; pd, predentin; asterisk, secreted enamel matrix.