Progressive alveolar bone loss in Ddr2
knockout. (A–H) Representative micro–computed
tomography (CT) images showing thin interradicular
alveolar bone (white arrowheads) and wide periodontal
ligament (PDL) spacing (white arrows) in
Ddr2slie/slie mice at 3 mo (B, F) and 10 mo (D, H) of age
compared with wild-type (WT). (I,
J) Three-dimensional reconstruction of
the lower jaw section showing severe bone defects (J, red
arrowhead) around lower teeth at 10 mo of age.
(K) Micro-CT analysis of bone
volume/total volume of interradicular alveolar bone of
first and second molars (n = 5–7
mice/group). (L–O) Representative
tartrate-resistant acid phosphatase (TRAP) staining images
showing osteoclasts (purple color, arrowheads in N–O)
along the alveolar bone surface at 10 mo of age.
(P) Shows quantification of osteoclast
numbers on frontal sections of the second molar alveolar
bone (n = 4 mice). *P
< 0.05. **P < 0.01.
***P < 0.001.
****P < 0.0001. Scale bar: 200
µm in L, M; 20 µm in N, O.