Dental findings in a child with osteopathia striata with cranial sclerosis (OS-CS): a case report.

The dental management of an 8-year-old girl with osteopathia striata with cranial sclerosis (OS-CS) is described. The girl presented with various oral abnormalities. The aim of this case report was to describe in detail the dental findings in a patient with OC-CS and the precautions to be taken when planning treatment. In the present case, many dental anomalies, such as delayed eruption of the permanent teeth, obliteration of the dental pulp, short roots, fused roots and taurodontism, were detected. In patients with OS-CS, routine dental care from an early stage is recommended to manage this anomaly properly.

Transposition of mesial and distal aspects of maxillary first molars: case report.

Congenital absence of one or more teeth, hypodontia, is the most common developmental anomaly and is often accompanied by the presence of other tooth anomalies. In this case two Japanese sisters have several congenitally missing primary and permanent teeth and morphological abnormalities of maxillary first molars. One sister has transposition of mesial and distal aspects of a maxillary first molar, whose cusps display a normal shape. Another sister has maxillary first molars, which look like maxillary second molars. Mesio-distally shift of teeth is a very rare anomaly making this particular case important to analyze the teeth formation and development.

Glycosphingolipids regulate ameloblastin expression in dental epithelial cells.

Neurotrophin 4 (NT-4) and its receptors regulate the differentiation of ameloblasts in tooth development. Gangliosides, sialic acids that contain glycosphingolipids (GSLs), are involved in a variety of membrane-associated cell physiological functions such as ligand-receptor signal transmission. However, the expression patterns and functions of GSLs during tooth development remain unclear. In this study, we identified strong expressions of GM3 and LacCer in dental epithelium, which give rise to differentiation into enamel-secreting ameloblasts. Exogenous GM3 and LacCer in dental epithelial cells induced the expression of ameloblastin (Ambn), while it was also interesting that GM3 synergistically exerted enhancement of NT-4-mediated Ambn expression. In addition, consistently exogenous GM3 and LacCer in dental epithelial cells induced distinct activation of extracellular signal-regulated kinase 1/2 (ERK1/2), an event upstream of the expression of Ambn. Furthermore, depletion of GSLs from dental epithelial cells by D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP) inhibited Ambn expression as well as phosphorylation of ERK1/2. In contrast, exogenous addition of GM3 or LacCer rescued the phosphorylation of ERK1/2 repressed by pre-treatment with D-PDMP. Taken together, these results suggest that GM3 and LacCer are essential for NT-4-mediated Ambn expression, and contribute to dental epithelial cell differentiation into ameloblasts.