Figure 3

Periodontal structures did not improve in nucleus-targeted Dmp1. (a) Radiographs of a 1-year-old mouse tooth. Note the combined periodontal-endodontic lesions in the second molar (arrows) and the exfoliation of the second molar (arrowheads). (b, c) Occlusal and buccal photographs of 1-year-old mouse tooth. Note the periodontitis with notable loss of periodontal attachment (arrows) and the exfoliation of the second molar with alveolar bone absorption (arrowheads). (d) Sirius Red-stained image under light microscopy (3-week-old mouse molars). Dark red indicates more collagen contents; light red means less collagen contents. (e) The same sections of (d) imaged under a polariscope (3-week-old mouse molars). (f) Anti-biglycan antibody staining of 3-week-old mouse molars. The biglycan was increased in the widened predentin (arrowheads) and the matrix of alveolar bone (asterisks), but was decreased in the PDL (arrows) in Dmp1^−/− and Dmp1^−/−; Col1α1-^NLSDMP1 groups. (g, h) Backscatter electron microscopy of alveolar bone. Dmp1^−/− and Dmp1^−/−; Col1α1-^NLSDMP1 groups showed the disorganization and hypomineralization of the trabeculae. AB, alveolar bone; DMP1, dentin matrix protein 1; HET, heterozygous; KO,knockout; PDL, periodontal ligament.