Figure 5. Combined effects of loss of Msx2 and Rank overexpression on mouse mandibular bone phenotype.

Microradiographs and scans of 16-week-old WT (a), Msx2 ^−/− (b), and Msx2 ^−/− Rank^Tg (c) mouse skulls were performed to compare characteristics of the bone of the mandible. While the Msx2 ^−/− mouse mandibular features (b) presented no major alterations compared to WT animals (a), Msx2 ^−/− Rank^Tg mice had marked disruptions in the architecture of the mandibular bone (c). These disruptions were either mono- or bilateral and were associated with conversion of the incisor epithelium toward massive osteolytic tumors (asterisks in c). Basal bone around these tumors was thinner (arrows in c), porous (arrow in c), and displaced, as seen in the upper view of the mandibular scan (c).