Understanding cell types and mechanisms of dental growth is essential for reconstruction and engineering of teeth. Therefore, we investigated cellular composition of growing and non-growing mouse and human teeth. As a result, we report an unappreciated cellular complexity of the continuously-growing mouse incisor, which suggests a coherent model of cell dynamics enabling unarrested growth. This model relies on spatially-restricted stem, progenitor and differentiated populations in the epithelial and mesenchymal compartments underlying the coordinated expansion of two major branches of pulpal cells and diverse epithelial subtypes. Further comparisons of human and mouse teeth yield both parallelisms and differences in tissue heterogeneity and highlight the specifics behind growing and non-growing modes. Despite being similar at a coarse level, mouse and human teeth reveal molecular differences and species-specific cell subtypes suggesting possible evolutionary divergence. Overall, here we provide an atlas of human and mouse teeth with a focus on growth and differentiation.

• MeSH
• buněčná diferenciace * genetika   MeSH
• dospělí MeSH
• epitelové buňky MeSH
• genetická heterogenita MeSH
• kmenové buňky cytologie   MeSH
• lidé MeSH
• mezoderm cytologie   růst a vývoj   metabolismus   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• modely u zvířat MeSH
• moláry cytologie   růst a vývoj   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• odontoblasty MeSH
• řezáky cytologie   růst a vývoj   MeSH
• vývojová regulace genové exprese MeSH
• zuby cytologie   růst a vývoj   MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Most mammals have two sets of teeth (diphyodont) - a deciduous dentition replaced by a permanent dentition; however, the mouse possesses only one tooth generation (monophyodont). In diphyodonts, the replacement tooth forms on the lingual side of the first tooth from the successional dental lamina. This lamina expresses the stem/progenitor marker Sox2 and has activated Wnt/β-catenin signalling at its tip. Although the mouse does not replace its teeth, a transient rudimentary successional dental lamina (RSDL) still forms during development. The mouse RSDL houses Sox2-positive cells, but no Wnt/β-catenin signalling. Here, we show that stabilising Wnt/β-catenin signalling in the RSDL in the mouse leads to proliferation of the RSDL and formation of lingually positioned teeth. Although Sox2 has been shown to repress Wnt activity, overexpression of Wnts leads to a downregulation of Sox2, suggesting a negative-feedback loop in the tooth. In the mouse, the first tooth represses the formation of the replacement, and isolation of the RSDL is sufficient to induce formation of a new tooth germ. Our data highlight key mechanisms that may have influenced the evolution of replacement teeth.This article has an associated 'The people behind the papers' interview.

• MeSH
• miniaturní prasata MeSH
• myši transgenní MeSH
• myši MeSH
• prasata MeSH
• proliferace buněk fyziologie   MeSH
• signální dráha Wnt fyziologie   MeSH
• transkripční faktory SOXB1 genetika   metabolismus   MeSH
• zubní zárodek cytologie   embryologie   MeSH
• zuby cytologie   embryologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Nowadays, regenerative and reparative medicine has grown in popularity. Dental stem cells are easily accessible source of adult stem cells. They can be harvested by a tooth extraction or spontaneous deciduous tooth exfoliation. They have to be isolated, expanded and stored until time they would be needed for individual stem cell therapy. Cryopreservation is both a short-term and long-term storage of tissues or cells at sub-zero temperatures. There are several methods of cryopreservation requiring different technologies. The objective of this review is to compare them and highlight their advantages and disadvantages.

• MeSH
• dospělé kmenové buňky cytologie   MeSH
• extrakce zubů MeSH
• kryoprezervace metody   MeSH
• lidé MeSH
• regenerativní lékařství MeSH
• transplantace kmenových buněk * MeSH
• vitrifikace * MeSH
• vypadávání zubů MeSH
• zubní dřeň cytologie   MeSH
• zuby mléčné cytologie   MeSH
• zuby cytologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

• MeSH
• apikoektomie metody   škodlivé účinky   MeSH
• autologní transplantace metody   MeSH
• biopsie klasifikace   MeSH
• chirurgická rána klasifikace   MeSH
• exostózy chirurgie   MeSH
• jehly klasifikace   MeSH
• krvácení do dutiny ústní ošetřování   MeSH
• lidé MeSH
• oroantrální píštěl chirurgie   diagnostické zobrazování   terapie   MeSH
• paranazální dutiny anatomie a histologie   chirurgie   MeSH
• preparace zubu klasifikace   přístrojové vybavení   MeSH
• protetická preparace zubu klasifikace   MeSH
• riziko MeSH
• slinné žlázy chirurgie   diagnostické zobrazování   MeSH
• stomatochirurgické výkony * klasifikace   metody   MeSH
• sutura klasifikace   MeSH
• ústa chirurgie   MeSH
• zaklíněný zub chirurgie   MeSH
• zuby chirurgie   cytologie   transplantace   MeSH
• Check Tag
• lidé MeSH

Teeth develop within the surrounding periodontal tissues, involving the alveolar bone, periodontal ligament and cementum. The alveolar bone originates through the process of intramembranous ossification involving mesenchymal cells from the tooth germ. As most available data are related to endochondral ossification, we examined the molecular background of alveolar bone development. We investigated the osteogenic profile of mesenchymal cells dissected from mouse mandible slices at the stage of early alveolar bone formation. Relative monitoring of gene expression was undertaken using PCR Arrays; this included the profiles of 84 genes associated with osteogenesis. To examine the tooth-bone interface, stages with detectable changes in bone remodelling during development (E13.0, E14.0 and E15.0) were chosen and compared with each other. These results showed a statistically significant increase in the expression of the genes Fgf3, Ctsk, Icam-1, Mmp9, Itga3 and Tuft1, and of a wide range of collagens (Col1a2, Col3a1, Col7a1, Col12a1, Col14a1). Decreased expression was detected in the case of Col2a1, Sox9, Smad2 and Vegfb. To confirm these changes in gene expression, immunofluorescence analyses of Mmp9 and Sox9 proteins were performed in situ. Our research has identified several candidate genes that may be crucial for the initiation of alveolar bone formation and is the basis for further functional studies.

• MeSH
• kolagen metabolismus   MeSH
• mezenchymální kmenové buňky cytologie   MeSH
• myši MeSH
• osteogeneze fyziologie   MeSH
• periodontální vaz metabolismus   MeSH
• vývoj kostí fyziologie   MeSH
• vývojová regulace genové exprese MeSH
• zubní zárodek embryologie   metabolismus   MeSH
• zuby cytologie   embryologie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The proper positioning of organs during development is essential, yet little is known about the regulation of this process in mammals. Using murine tooth development as a model, we have found that cell migration plays a central role in positioning of the organ primordium. By combining lineage tracing, genetic cell ablation, and confocal live imaging, we identified a migratory population of Fgf8-expressing epithelial cells in the embryonic mandible. These Fgf8-expressing progenitors furnish the epithelial cells required for tooth development, and the progenitor population migrates toward a Shh-expressing region in the mandible, where the tooth placode will initiate. Inhibition of Fgf and Shh signaling disrupted the oriented migration of cells, leading to a failure of tooth development. These results demonstrate the importance of intraepithelial cell migration in proper positioning of an initiating organ.

• MeSH
• epitelové buňky cytologie   metabolismus   MeSH
• fibroblastové růstové faktory metabolismus   MeSH
• mezoderm cytologie   metabolismus   MeSH
• moláry cytologie   embryologie   metabolismus   MeSH
• morfogeneze fyziologie   MeSH
• myši MeSH
• odontogeneze fyziologie   MeSH
• pohyb buněk fyziologie   MeSH
• vývojová regulace genové exprese fyziologie   MeSH
• zuby cytologie   embryologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

The transcription factor c-Myb is involved in the control of cell proliferation, survival and differentiation. As these processes accompany the morphogenesis of developing teeth, this work investigates the possible role of c-Myb during odontogenesis. Analysis of the expression of c-Myb in the monophyodont mouse was followed by similar analysis in a diphyodont species, the pig, which has a dentition more closely resembling that of the human. The distribution of c-Myb was correlated with the pattern of proliferation and apoptosis and the tooth phenotype of c-Myb mutant mice was also assessed. In the mouse, c-Myb expression was detected throughout prenatal development of the first molar tooth. Negative temporospatial correlation was found between c-Myb expression and apoptosis, while c-Myb expression positively correlated with proliferation. c-Myb-positive cells, however, were more abundant than the proliferating cell nuclear antigen positive cells, suggesting other roles of c-Myb in odontogenesis. In the minipig, in contrast to the mouse, there was an asymmetrical arrangement of c-Myb positive cells, with a higher presence on the labial side of the tooth germ and dental lamina. A cluster of negative cells was situated in the mesenchyme close to the tooth bud. At later stages, the number of positive cells decreased and these cells were situated in the upper part of the dental papilla in the areas of future cusp formation. The expression of c-Myb in both species was strong in the odontoblasts and ameloblasts at the stage of dentin and enamel production suggesting a possible novel role of c-Myb during tooth mineralization.

• MeSH
• alely MeSH
• ameloblasty cytologie   metabolismus   MeSH
• apoptóza MeSH
• dentice MeSH
• druhová specificita MeSH
• embryo savčí cytologie   embryologie   metabolismus   MeSH
• imunohistochemie MeSH
• klonování DNA MeSH
• koncové značení zlomů DNA in situ MeSH
• miniaturní prasata MeSH
• myši MeSH
• odontoblasty cytologie   metabolismus   MeSH
• odontogeneze MeSH
• osteoklasty cytologie   metabolismus   MeSH
• prasata MeSH
• proliferace buněk MeSH
• proliferační antigen buněčného jádra metabolismus   MeSH
• proteiny buněčného cyklu genetika   metabolismus   MeSH
• protoonkogenní proteiny c-myb genetika   metabolismus   MeSH
• trans-aktivátory genetika   metabolismus   MeSH
• vývojová regulace genové exprese MeSH
• zuby cytologie   embryologie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The oral cavity of vertebrates is generally thought to arise as an ectodermal invagination. Consistent with this, oral teeth are proposed to arise exclusively from ectoderm, contributing to tooth enamel epithelium, and from neural crest derived mesenchyme, contributing to dentin and pulp. Yet in many vertebrate groups, teeth are not restricted only to the oral cavity, but extend posteriorly as pharyngeal teeth that could be derived either directly from the endodermal epithelium, or from the ectodermal epithelium that reached this location through the mouth or through the pharyngeal slits. However, when the oropharyngeal membrane, which forms a sharp ecto/endodermal border, is broken, the fate of these cells is poorly known. Here, using transgenic axolotls with a combination of fate-mapping approaches, we present reliable evidence of oral teeth derived from both the ectoderm and endoderm and, moreover, demonstrate teeth with a mixed ecto/endodermal origin. Despite the enamel epithelia having a different embryonic source, oral teeth in the axolotl display striking developmental uniformities and are otherwise identical. This suggests a dominant role for the neural crest mesenchyme over epithelia in tooth initiation and, from an evolutionary point of view, that an essential factor in teeth evolution was the odontogenic capacity of neural crest cells, regardless of possible 'outside-in' or 'inside-out' influx of the epithelium.

• MeSH
• Ambystoma mexicanum embryologie   MeSH
• ektoderm cytologie   embryologie   MeSH
• endoderm cytologie   embryologie   MeSH
• epitel MeSH
• financování organizované MeSH
• geneticky modifikovaná zvířata MeSH
• morfogeneze MeSH
• zuby cytologie   embryologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH

Summary: Human adult mesenchymal stem cells (MSCs) are rare elements living in various organs (e.g. bone marrow, skeletal muscle), with capability to differentiate in various cell types (e.g. chondrocytes, adipocytes and osteoblasts). In the year 2000, Gronthos and co-workers isolated stem cells from the human dental pulp (DPSCs). Later on, stem cells from exfoliated tooth were also obtained. The aims of our study were to establish protocol of DPSCs isolation and to cultivate DPSCs either from adult or exfoliated tooth, and to compare these cells with mesenchymal progenitor cell (MPCs) cultures. MPCs were isolated from the human bone marrow of proximal femur. DPSCs were isolated from deciduous and permanent teeth. Both cell types were cultivated under the same conditions in the media with 2 % of FCS supplemented with PDGF and EGF growth factors. We have cultivated undifferentiated DPSCs for long time, over 60 population doublings in cultivation media designed for bone marrow MPCs. After reaching Hayflick’s limit, they still have normal karyotype. Initial doubling time of our cultures was from 12 to 50 hours for first 40 population doublings, after reaching 50 population doublings, doubling time had increased to 60–90 hours. Regression analysis of uncumulated population doublings proved tight dependence of population doublings on passage number and slow decrease of proliferation potential. In comparison with bone marrow MPCs, DPSCs share similar biological characteristics and stem cell properties. The results of our experiments proved that the DPSCs and MPCs are highly proliferative, clonogenic cells that can be expanded beyond Hayflick’s limit and remain cytogenetically stable. Moreover we have probably isolated two different populations of DPSCs. These DPSCs lines differed one from another in morphology. Because of their high proliferative and differentiation potential, DPSCs can become more attractive, easily accessible source of adult stem cells for therapeutic purposes.

• MeSH
• buňky kostní dřeně cytologie   fyziologie   MeSH
• femur cytologie   fyziologie   růst a vývoj   MeSH
• finanční podpora výzkumu jako téma MeSH
• kultivované buňky cytologie   MeSH
• lidé MeSH
• mezenchymální kmenové buňky cytologie   fyziologie   MeSH
• průtoková cytometrie metody   využití   MeSH
• výběr dárců metody   využití   MeSH
• zubní dřeň cytologie   růst a vývoj   MeSH
• zuby cytologie   fyziologie   růst a vývoj   MeSH
• Check Tag
• lidé MeSH