Dental and periodontal phenotype in sclerostin knockout mice

Abstract

A protein that alters bone and dental support structures does not affect tooth development, which has been reported by researchers in Austria and Switzerland. A team led by Reinhard Gruber, from both the Medical University of Vienna, Austria, and the University of Bern, Switzerland, analysed the lower jaws of mice engineered to lack a functioning copy of a gene called Sost. This gene encodes the protein sclerostin, which inhibits bone formation. Scientists knew that sclerostin was expressed by bone-resorbing cells called osteocytes and cementocytes, which form the modified bone found around the root of teeth. Gruber and colleagues found abnormalities in the structures surrounding the first molars of the mice lacking sclerostin. However, they found no significant defects in tooth dimensions. The work has implications for periodontal regeneration, implant dentistry and dentin formation.

Keywords

alveolar bone / micro-computed tomography / mouse / periodontium / sclerostin / tooth

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