Figure 2: Enamel rod patterns of mandibular incisors from wild-type and Mmp20 null mice. The wild-type enamel had crisscrossing (decussating) rows of enamel rods (a). The Mmp20 null enamel may have a poorly organized rod pattern (b), no rod pattern with a poorly organized rod layer beneath (c), or virtually no rod pattern whatsoever (d). 1 and 2 designate the two different enamel layers. All magnification bars are 10 μm in length. This figure was originally published in: Bartlett et al. Eur J Oral Sci. 119 (Suppl 1): 199-205, 2011. D01:10.1111/j.1600-0722.2011.00864.x.