Spatiotemporal Expression of Sclerostin in Odontoblasts during Embryonic Mouse Tooth Morphogenesis

Introduction: Sclerostin is the product of the SOST gene. Loss-of-function mutations in the SOST gene result in a high bone mass phenotype, thus confirming that sclerostin is a negative regulator of bone mass. SOST knockdown in humans also causes oral and dental malformations. However, the relationship between sclerostin and tooth development is unclear. Methods: Using immunohistochemical techniques, we investigated sclerostin expression during fetal mouse tooth development and adult mouse tooth morphogenesis. Results: Sclerostin was expressed in the secretory odontoblasts located along the ameloblasts of fetal mouse tooth germ and adult incisor. Sclerostin expression was also observed in the fetal and adult osteocytes in the jaw bone. Conclusion: These results suggest that sclerostin, one of the important regulatory factors of differentiated odontoblast function, may usable in vital pulp therapy. (J Endod 2011;37:340-345)