Changes in the craniofacial morphology in sclerostin knockout mice.

OBJECTIVES

To investigate the influence of lack of sclerostin on craniofacial morphology in sclerostin gene (Sost) knockout (SostΔ26/Δ26) mice.

DESIGN

Micro computed tomography (micro-CT) was performed on both 60-day-old wild-type and SostΔ26/Δ26 mice to analyze changes in craniofacial morphology. Ten anatomical landmarks and eight measurement parameters as well as the total mandibular volume were used to assess craniofacial features. In addition, the femora of both wild-type and SostΔ26/Δ26 mice were examined using micro-CT and histological analysis. Cancellous bone volume, cortical bone volume, and the number of osteoclasts beneath the growth plate in the femora were evaluated.

RESULTS

The neurocranium was significantly smaller in the SostΔ26/Δ26 mice than in the wild-type mice, while the length of the angular process of the mandible was significantly greater. The total mandibular volume was significantly larger in the SostΔ26/Δ26 mice than in the wild-type mice. The volume of cancellous bone and cortical bone in the femora were significantly larger in the SostΔ26/Δ26 mice than in the littermate wild-type mice. Histological observation showed no statistically significant difference in the number of osteoclasts present in the femora between wild-type mice and SostΔ26/Δ26 mice.

CONCLUSIONS

The present study showed a significant decrease in neurocranium and a significant increase in mandibular bone in SostΔ26/Δ26 mice compared to wild-type mice, along with increased volumes of cancellous and cortical bone in the femora.