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Sample records for arrests tooth development

  1. Disruption of Wnt/β-catenin Signaling in Odontoblasts and Cementoblasts Arrests Tooth Root Development in Postnatal Mouse Teeth

    OpenAIRE

    Zhang, Ran; Yang, Guan; Wu, Ximei; Xie, Jing; Yang, Xiao; Li, Tiejun

    2013-01-01

    Tooth development undergoes a series of complex reciprocal interactions between dental epithelium and the underlying mesenchymal cells. Compared with the study in tooth crown formation, little is known about the molecular mechanism underlying the development of tooth roots. In the present study, we conditionally knock out β-catenin gene (Ctnnb1) within developing odontoblasts and cementoblasts during the development of tooth roots, and observed rootless molars as well as incomplete incisors. ...

  2. Developmental toxicity of dioxin to mouse embryonic teeth in vitro: arrest of tooth morphogenesis involves stimulation of apoptotic program in the dental epithelium

    International Nuclear Information System (INIS)

    Previous studies have shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can arrest molar tooth development in rats after in utero and lactational exposure, and that the sensitive stage is temporally restricted. To define the stage in which TCDD is able to arrest tooth development and the cellular background of the effect, mouse embryonic molar tooth explants including various early developmental stages from initiation to late cap stage were exposed to TCDD in organ culture. TCDD did not inhibit morphogenesis of the first molar teeth including the early bud-staged E12 first molars, but the teeth were smaller than in control cultures. Accordingly, the second molars underwent morphogenesis in the presence of TCDD when explanted at E15 when they were at the bud stage. TCDD arrested their development when explanted at E14 when they had not yet reached the early bud stage. Immunohistochemical localization of incorporated bromodeoxyuridine in cultured E14 teeth showed that TCDD did not affect cell proliferation. Localization of apoptosis by terminal deoxynucleotidyl transferase (TdT)-mediated nick end labeling (TUNEL) method revealed that TCDD enhanced apoptosis of dental epithelial cells, especially in the dental lamina of both the first and second molars, and in the inner dental epithelium at the cusp tips of the first molars. Thus, TCDD can arrest tooth development in vitro if the exposure starts at the initiation stage, whereas exposure at later stages leads to smaller tooth size and deformation of cuspal morphology. TCDD interferes with tooth development by stimulating apoptosis in those cells of the dental epithelium, which are predetermined to undergo apoptosis during normal development

  3. Fus Expression Patterns in Developing Tooth

    OpenAIRE

    Kim, Eun-Jung; Lee, Jong-Min; Jung, Han-Sung

    2013-01-01

    Recently, the RNA/DNA-binding protein FUS, Fused in sarcoma, was shown to play a role in growth, differentiation, and morphogenesis in vertebrates. Because little is known about Fus, we investigated its expression pattern in murine tooth development. In situ hybridization of mouse mandibles at specific developmental stages was performed with a DIG-labeled RNA probe. During early tooth development, Fus was detected in the dental epithelium and dental mesenchyme at 11 days postcoitum (dpc) and ...

  4. Hedgehog signaling is required at multiple stages of zebrafish tooth development

    Directory of Open Access Journals (Sweden)

    Stock David W

    2010-11-01

    Full Text Available Abstract Background The accessibility of the developing zebrafish pharyngeal dentition makes it an advantageous system in which to study many aspects of tooth development from early initiation to late morphogenesis. In mammals, hedgehog signaling is known to be essential for multiple stages of odontogenesis; however, potential roles for the pathway during initiation of tooth development or in later morphogenesis are incompletely understood. Results We have identified mRNA expression of the hedgehog ligands shha and the receptors ptc1 and ptc2 during zebrafish pharyngeal tooth development. We looked for, but did not detect, tooth germ expression of the other known zebrafish hedgehog ligands shhb, dhh, ihha, or ihhb, suggesting that as in mammals, only Shh participates in zebrafish tooth development. Supporting this idea, we found that morphological and gene expression evidence of tooth initiation is eliminated in shha mutant embryos, and that morpholino antisense oligonucleotide knockdown of shha, but not shhb, function prevents mature tooth formation. Hedgehog pathway inhibition with the antagonist compound cyclopamine affected tooth formation at each stage in which we applied it: arresting development at early stages and disrupting mature tooth morphology when applied later. These results suggest that hedgehog signaling is required continuously during odontogenesis. In contrast, over-expression of shha had no effect on the developing dentition, possibly because shha is normally extensively expressed in the zebrafish pharyngeal region. Conclusion We have identified previously unknown requirements for hedgehog signaling for early tooth initiation and later morphogenesis. The similarity of our results with data from mouse and other vertebrates suggests that despite gene duplication and changes in the location of where teeth form, the roles of hedgehog signaling in tooth development have been largely conserved during evolution.

  5. Apoptotic cell elimination during early tooth development

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Míšek, Ivan; Chovancová, Eva

    2003-01-01

    Roč. 72, č. 7 (2003), s. 34. ISSN 0001-7213. [Congress of the European Association of Veterinary Anatomists/24./. 21.07.2002-25.07.2002, Brno] R&D Projects: GA ČR GP204/02/P112 Institutional research plan: CEZ:AV0Z5045916 Keywords : tooth development Subject RIV: FF - HEENT, Dentistry

  6. Bivalent histone modifications during tooth development

    Institute of Scientific and Technical Information of China (English)

    Li-Wei Zheng; Bin-Peng Zhang; Ruo-Shi Xu; Xin Xu; Ling Ye; Xue-Dong Zhou

    2014-01-01

    Histone methylation is one of the most widely studied post-transcriptional modifications. It is thought to be an important epigenetic event that is closely associated with cell fate determination and differentiation. To explore the spatiotemporal expression of histone H3 lysine 4 trimethylation (H3K4me3) and histone H3 lysine 27 trimethylation (H3K27me3) epigenetic marks and methylation or demethylation transferases in tooth organ development, we measured the expression of SET7, EZH2, KDM5B and JMJD3 via immunohistochemistry and quantitative polymerase chain reaction (qPCR) analysis in the first molar of BALB/c mice embryos at E13.5, E15.5, E17.5, P0 and P3, respectively. We also measured the expression of H3K4me3 and H3K27me3 with immunofluorescence staining. During murine tooth germ development, methylation or demethylation transferases were expressed in a spatial–temporal manner. The bivalent modification characterized by H3K4me3 and H3K27me3 can be found during the tooth germ development, as shown by immunofluorescence. The expression of SET7, EZH2 as methylation transferases and KDM5B and JMJD3 as demethylation transferases indicated accordingly with the expression of H3K4me3 and H3K27me3 respectively to some extent. The bivalent histone may play a critical role in tooth organ development via the regulation of cell differentiation.

  7. Tooth development in incisor region of sheep

    Czech Academy of Sciences Publication Activity Database

    Míšek, Ivan

    Olomouc: -, 2008 - (Bezdičková, M.; Molíková, R.). s. 128-128 ISBN 978-80-244-2061-5. [Morphology 2008. Lojda Symposium on Histochemistry /45./. 08.09.2008-10.09.2008, Olomouc] R&D Projects: GA ČR GC524/08/J032 Institutional research plan: CEZ:AV0Z50450515 Keywords : tooth development * sheep Subject RIV: FF - HEENT, Dentistry

  8. Expression of Clock Proteins in Developing Tooth

    OpenAIRE

    Zheng, Li; Papagerakis, Silvana; Schnell, Santiago D.; Hoogerwerf, Willemijntje A; Papagerakis, Petros

    2010-01-01

    Morphological and functional changes during ameloblast and odontoblast differentiation suggest that enamel and dentin formation is under circadian control. Circadian rhythms are endogenous self-sustained oscillations with periods of 24 hours that control diverse physiological and metabolic processes. Mammalian clock genes play a key role in synchronizing circadian functions in many organs. However, close to nothing is known on clock genes expression during tooth development. In this work, we ...

  9. Primary Cilia Integrate Hedgehog and Wnt Signaling during Tooth Development

    OpenAIRE

    B. Liu; Chen, S.; Cheng, D; Jing, W.; Helms, J.A.

    2014-01-01

    Many ciliopathies have clinical features that include tooth malformations but how these defects come about is not clear. Here we show that genetic deletion of the motor protein Kif3a in dental mesenchyme results in an arrest in odontogenesis. Incisors are completely missing, and molars are enlarged in Wnt1Cre+Kif3afl/fl embryos. Although amelogenesis and dentinogenesis initiate in the molar tooth bud, both processes terminate prematurely. We demonstrate that loss of Kif3a in dental mesenchyme...

  10. The Tooth Wear Evaluation System: development and applications

    OpenAIRE

    Wetselaar, P.

    2016-01-01

    Tooth wear is a multifactorial condition, leading to the loss of dental hard tissues, viz., enamel and dentine. Because of its multifactorial etiology, tooth wear can manifest itself in many different representations, and therefore it can be difficult and demanding to diagnose and manage the condition. In this thesis, the development of a comprehensive modular system is described, the Tooth Wear Evaluation System (TWES). With this system, one can recognize the problem (viz., qualifying the to...

  11. ClC-7 Deficiency Impairs Tooth Development and Eruption.

    Science.gov (United States)

    Wang, He; Pan, Meng; Ni, Jinwen; Zhang, Yanli; Zhang, Yutao; Gao, Shan; Liu, Jin; Wang, Zhe; Zhang, Rong; He, Huiming; Wu, Buling; Duan, Xiaohong

    2016-01-01

    CLCN7 gene encodes the voltage gated chloride channel 7 (ClC-7) in humans. The mutations in CLCN7 have been associated with osteopetrosis in connection to the abnormal osteoclasts functions. Previously, we found that some osteopetrosis patients with CLCN7 mutations suffered from impacted teeth and root dysplasia. Here we set up two in vivo models under a normal or an osteoclast-poor environment to investigate how ClC-7 affects tooth development and tooth eruption. Firstly, chitosan-Clcn7-siRNA nanoparticles were injected around the first maxillary molar germ of newborn mice and caused the delay of tooth eruption and deformed tooth with root dysplasia. Secondly, E13.5 molar germs infected with Clcn7 shRNA lentivirus were transplanted under the kidney capsule and presented the abnormal changes in dentin structure, periodontal tissue and cementum. All these teeth changes have been reported in the patients with CLCN7 mutation. In vitro studies of ameloblasts, odontoblasts and dental follicle cells (DFCs) were conducted to explore the involved mechanism. We found that Clcn7 deficiency affect the differentiation of these cells, as well as the interaction between DFCs and osteoclasts through RANKL/OPG pathway. We conclude that ClC-7 may affect tooth development by directly targeting tooth cells, and regulate tooth eruption through DFC mediated osteoclast pathway. PMID:26829236

  12. Modification of tooth development by heat shock protein 60

    OpenAIRE

    Papp Tamás; Polyák Angéla; Papp Krisztina; Mészár Zoltán (1977-) (állatorvos); Zákány Róza (1963-) (anatómus-, kötőszövetbiológus); Mészár-Katona Éva (1986-) (Ph.D hallgató); Terdik Tünde (1969-) (analitikus); Chang, Hwa Ham; Felszeghy Szabolcs Béla (1972-) (fogorvos, anatómus, kötőszövetbiológus)

    2016-01-01

    Although several heat shock proteins have been investigated in relation to tooth development, no available information is available about the spatial and temporal expression pattern of heat shock protein 60 (Hsp 60). To characterize Hsp 60 expression in the structures of the developing tooth germ, we used Western blotting, immunohistochemistry and in situ hybridization. Hsp 60 was present in high amounts in the inner and outer enamel epithelia, enamel knot (EK) and stratum intermedium (SI). H...

  13. Caspase-7 in molar tooth development

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Vanden Berghe, T.; Švandová, Eva; Vandenabeele, P.; Healy, C.; Sharpe, P. T.; Tucker, A. S.

    2012-01-01

    Roč. 57, č. 11 (2012), s. 1474-1481. ISSN 0003-9969 R&D Projects: GA AV ČR IAA600450904 Grant ostatní: GA ČR(CZ) GAP502/12/1285 Institutional research plan: CEZ:AV0Z50450515 Keywords : tooth * apoptosis * mineralisation Subject RIV: FF - HEENT, Dentistry Impact factor: 1.549, year: 2012

  14. The development of complex tooth shape in reptiles

    Directory of Open Access Journals (Sweden)

    Oldrich eZahradnicek

    2014-02-01

    Full Text Available Reptiles have a diverse array of tooth shapes, from simple unicuspid to complex multicuspid teeth, reflecting functional adaptation to a variety of diets and eating styles. In addition to cusps, often complex longitudinal labial and lingual enamel crests are widespread and contribute to the final shape of reptile teeth. The simplest shaped unicuspid teeth have been found in piscivorous or carnivorous ancestors of recent diapsid reptiles and they are also present in some extant carnivores such as crocodiles and snakes. However, the ancestral tooth shape for squamate reptiles is thought to be bicuspid, indicating an insectivorous diet. The development of bicuspid teeth in lizards has recently been published, indicating that the mechanisms used to create cusps and crests are very distinct from those that shape cusps in mammals. Here, we introduce the large variety of tooth shapes found in lizards and compare the morphology and development of bicuspid, tricuspid and pentacuspid teeth, with the aim of understanding how such tooth shapes are generated. Next, we discuss whether the processes used to form such morphologies are conserved between divergent lizards and whether the underlying mechanisms share similarities with those of mammals. In particular, we will focus on the complex teeth of the chameleon, gecko, varanus and anole lizards using SEM and histology to compare the tooth crown morphology and embryonic development.

  15. The development of complex tooth shape in reptiles.

    Science.gov (United States)

    Zahradnicek, Oldrich; Buchtova, Marcela; Dosedelova, Hana; Tucker, Abigail S

    2014-01-01

    Reptiles have a diverse array of tooth shapes, from simple unicuspid to complex multicuspid teeth, reflecting functional adaptation to a variety of diets and eating styles. In addition to cusps, often complex longitudinal labial and lingual enamel crests are widespread and contribute to the final shape of reptile teeth. The simplest shaped unicuspid teeth have been found in piscivorous or carnivorous ancestors of recent diapsid reptiles and they are also present in some extant carnivores such as crocodiles and snakes. However, the ancestral tooth shape for squamate reptiles is thought to be bicuspid, indicating an insectivorous diet. The development of bicuspid teeth in lizards has recently been published, indicating that the mechanisms used to create cusps and crests are very distinct from those that shape cusps in mammals. Here, we introduce the large variety of tooth shapes found in lizards and compare the morphology and development of bicuspid, tricuspid, and pentacuspid teeth, with the aim of understanding how such tooth shapes are generated. Next, we discuss whether the processes used to form such morphologies are conserved between divergent lizards and whether the underlying mechanisms share similarities with those of mammals. In particular, we will focus on the complex teeth of the chameleon, gecko, varanus, and anole lizards using SEM and histology to compare the tooth crown morphology and embryonic development. PMID:24611053

  16. Modification of tooth development by heat shock protein 60.

    Science.gov (United States)

    Papp, Tamas; Polyak, Angela; Papp, Krisztina; Meszar, Zoltan; Zakany, Roza; Meszar-Katona, Eva; Tünde, Palne Terdik; Ham, Chang Hwa; Felszeghy, Szabolcs

    2016-01-01

    Although several heat shock proteins have been investigated in relation to tooth development, no available information is available about the spatial and temporal expression pattern of heat shock protein 60 (Hsp 60). To characterize Hsp 60 expression in the structures of the developing tooth germ, we used Western blotting, immunohistochemistry and in situ hybridization. Hsp 60 was present in high amounts in the inner and outer enamel epithelia, enamel knot (EK) and stratum intermedium (SI). Hsp 60 also appeared in odontoblasts beginning in the bell stage. To obtain data on the possible effect of Hsp 60 on isolated lower incisors from mice, we performed in vitro culturing. To investigate the effect of exogenous Hsp 60 on the cell cycle during culturing, we used the 5-bromo-2-deoxyuridine (BrdU) incorporation test on dental cells. Exogenously administered Hsp 60 caused bluntness at the apical part of the 16.5-day-old tooth germs, but it did not influence the proliferation rate of dental cells. We identified the expression of Hsp 60 in the developing tooth germ, which was present in high concentrations in the inner and outer enamel epithelia, EK, SI and odontoblasts. High concentration of exogenous Hsp 60 can cause abnormal morphology of the tooth germ, but it did not influence the proliferation rate of the dental cells. Our results suggest that increased levels of Hsp 60 may cause abnormalities in the morphological development of the tooth germ and support the data on the significance of Hsp during the developmental processes. PMID:27025262

  17. An Nfic-hedgehog signaling cascade regulates tooth root development.

    Science.gov (United States)

    Liu, Yang; Feng, Jifan; Li, Jingyuan; Zhao, Hu; Ho, Thach-Vu; Chai, Yang

    2015-10-01

    Coordination between the Hertwig's epithelial root sheath (HERS) and apical papilla (AP) is crucial for proper tooth root development. The hedgehog (Hh) signaling pathway and Nfic are both involved in tooth root development; however, their relationship has yet to be elucidated. Here, we establish a timecourse of mouse molar root development by histological staining of sections, and we demonstrate that Hh signaling is active before and during root development in the AP and HERS using Gli1 reporter mice. The proper pattern of Hh signaling activity in the AP is crucial for the proliferation of dental mesenchymal cells, because either inhibition with Hh inhibitors or constitutive activation of Hh signaling activity in transgenic mice leads to decreased proliferation in the AP and shorter roots. Moreover, Hh activity is elevated in Nfic(-/-) mice, a root defect model, whereas RNA sequencing and in situ hybridization show that the Hh attenuator Hhip is downregulated. ChIP and RNAscope analyses suggest that Nfic binds to the promoter region of Hhip. Treatment of Nfic(-/-) mice with Hh inhibitor partially restores cell proliferation, AP growth and root development. Taken together, our results demonstrate that an Nfic-Hhip-Hh signaling pathway is crucial for apical papilla growth and proper root formation. This discovery provides insight into the molecular mechanisms regulating tooth root development. PMID:26293299

  18. Genome-Wide Association Study Reveals Multiple Loci Associated with Primary Tooth Development during Infancy

    OpenAIRE

    Pillas, D.; Hoggart, C. J.; Evans, D. M.; O'Reilly, P. F.; Sipila, K.; Lahdesmaki, R.; Millwood, I. Y.; Kaakinen, M; Netuveli, G.; Blane, D; Charoen, P.; Sovio, U; Pouta, A.; Freimer, N; Hartikainen, A. L.

    2010-01-01

    Tooth development is a highly heritable process which relates to other growth and developmental processes, and which interacts with the development of the entire craniofacial complex. Abnormalities of tooth development are common, with tooth agenesis being the most common developmental anomaly in humans. We performed a genome-wide association study of time to first tooth eruption and number of teeth at one year in 4,564 individuals from the 1966 Northern Finland Birth Cohort (NFBC1966) and 1,...

  19. Runx2, Osx, and Dspp in Tooth Development

    OpenAIRE

    Chen, S.; Gluhak-Heinrich, J.; Wang, Y. H.; Wu, Y. M.; Chuang, H. H.; Chen, L.; Yuan, G. H.; Dong, J.; Gay, I.; MacDougall, M.

    2009-01-01

    The transcription factors Runx2 and Osx are necessary for osteoblast and odontoblast differentiation, while Dspp is important for odontoblast differentiation. The relationship among Runx2, Osx, and Dspp during tooth and craniofacial bone development remains unknown. In this study, we hypothesized that the roles of Runx2 and Osx in the regulation of osteoblast and odontoblast lineages may be independent of one another. The results showed that Runx2 expression overlapped with Osx in dental and ...

  20. Molar tooth development in caspase-3 deficient mice

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Sharpe, P. T.; Lakhani, S. A.; Roth, K. A.; Flavell, R. A.; Šetková, Jana; Míšek, Ivan; Tucker, A. S.

    2006-01-01

    Roč. 50, 5 (2006), s. 491-497. ISSN 0214-6282 R&D Projects: GA AV ČR KJB500450503; GA MŠk OC B23.001 Grant ostatní: European Molecular Biology Organization ASTF195.00-05; NIH NS41962 Institutional research plan: CEZ:AV0Z50450515 Keywords : tooth development * dental apoptosis * caspase-3 mutant Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.577, year: 2006

  1. Regional odontodysplasia: A case of progressive tooth development

    Directory of Open Access Journals (Sweden)

    R Ganguly

    2012-01-01

    Full Text Available Regional odontodysplasia (RO is considered a relatively rare dental anomaly despite increasing numbers of case reports in recent years. It usually presents as a localized anomaly in tooth development affecting a few adjacent teeth in a single maxillary or mandibular quadrant. The purpose of this paper is to describe an uncommon case of regional odotodysplasia involving noncontiguous mandibular teeth, crossing the midline in a male patient, and showing progressive normalization of tooth anatomy over a period of 6 years. Typically, teeth affected with RO become pulpally involved early on and are either extracted or endodontically treated. Such reports of automatic normalization over time in RO is supportive of a more conservative treatment approach.

  2. Development of the canine tooth in the beagle

    International Nuclear Information System (INIS)

    The growth of the crown and root in the canine tooth of beagle dogs were observed macroscopically and radiographically, and changes of occlusion with age were investigated. Completion of growth in the crown of the canine tooth was observed in both mandible and maxilla, and its eruption was accompanied by development of the dental root. The permanent canine erupted on the lingual side of deciduous canine in the mandible, and on the mesial side of the deciduous canine in the maxilla. Movement of the permanent canine to normal occlusal position(buccal direction in mandibular canine, and distal direction in maxillary canine)was followed by the loss of the deciduous canine. Coexistence of the permanent and deciduous canines occurred for about 2.4 weeks in the maxilla and about 1.4 weeks in the mandible, on average. Macroscopically, the growth of the permanent canine was completed by 33 weeks of age in the mandible and about 34 weeks of age in the maxilla. The mature root of the permanent canine was recognized radiographically at about 43 weeks of age in the mandible and 47 weeks of age in the maxilla

  3. Morphometric approach to pulp fibroblast development in tooth germ.

    Science.gov (United States)

    Căruntu, Irina-Draga; Săvinescu, Sergiu Daniel; Amălinei, Cornelia

    2014-01-01

    This paper builds a morphometric framework for the analysis of dental pulp fibroblast evolution during tooth development. We investigated 15 tooth germs (cases) organized, by histological criteria, in three groups corresponding to cap, early bell, and late bell stages, respectively. Each group comprised five cases. The morphometric description used the following parameters: area (A), perimeter (P)--automatically extracted by a color segmentation technique, and form factor (FF)--calculated as 4πA/P (2). The designed framework operated at inter- and intragroup levels. The intergroup analysis quantified the differences between groups, in the sense of a relative distance (RD) adequately defined by mean-value scaling. We showed that the stage of early bell is approximately 5 times closer to late bell than to cap. The quantification procedure required concomitant information about A, P parameters (as P versus A dependences, or FF values), whereas the procedure failed for A or P separately used. The intragroup analysis quantified the similarity of the cases belonging to the same stage. We proved that, unlike the intergroup tests, the individual exploitation of all three descriptors A, P, and FF is effective, yielding highly compatible results. Within any group, most cases presented RDs less than 10% from the group mean value, regardless of the descriptor type. PMID:25057501

  4. Wnt5a regulates growth, patterning, and odontoblast differentiation of developing mouse tooth

    OpenAIRE

    Lin, Minkui; Li, Lu; Liu, Chao; Hongbing LIU; He, Fenglei; Yan, Fuhua; Zhang, Yanding; Chen, Yiping

    2011-01-01

    Wnt/β-catenin signaling is essential for tooth development beyond the bud stage, but little is known about the role of non-canonical Wnt signaling in odontogenesis. Here we compared the expression of Wnt5a, a representative of noncanonical Wnts, with that of Ror2, the Wnt5a receptor for non-canonical signaling, in the developing tooth, and analyzed tooth phenotype in Wnt5a mutants. Wnt5a deficient mice exhibit retarded tooth development beginning from E16.5, leading to the formation of smalle...

  5. Mouse Embryonic Diastema Region Is an Ideal Site for the Development of Ectopically Transplanted Tooth Germ

    OpenAIRE

    Song, Yiqiang; Yan, Mingquan; Muneoka, Ken; Chen, Yiping

    2008-01-01

    The anterior eye chamber and the kidney capsule of the mouse have been traditionally used for long-term culture of tooth germ grafts. However, although these sites provide an excellent growth environment, they do not represent real in situ sites for the development of a grafted tooth germ. Here, we describe a protocol to transplant a tooth germ into the mandibular diastema region of mouse embryos using exo utero surgery. Our results demonstrate that the mouse embryonic diastema region represe...

  6. Immunohistochemical Examination for the Distribution of Podoplanin-Expressing Cells in Developing Mouse Molar Tooth Germs

    OpenAIRE

    Imaizumi, Yuri; Amano, Ikuko; Tsuruga, Eichi; Kojima, Hiroshi; Sawa, Yoshihiko

    2010-01-01

    We recently reported the expression of podoplanin in the apical bud of adult mouse incisal tooth. This study was aimed to investigate the distribution of podoplanin-expressing cells in mouse tooth germs at several developing stages. At the bud stage podoplanin was expressed in oral mucous epithelia and in a tooth bud. At the cap stage podoplanin was expressed on inner and outer enamel epithelia but not in mesenchymal cells expressing the neural crest stem cell marker nestin. At the early bell...

  7. Beta-Catenin and Plakoglobin Expression during Zebrafish Tooth Development and Replacement.

    Science.gov (United States)

    Verstraeten, Barbara; van Hengel, Jolanda; Huysseune, Ann

    2016-01-01

    We analyzed the protein distribution of two cadherin-associated molecules, plakoglobin and β-catenin, during the different stages of tooth development and tooth replacement in zebrafish. Plakoglobin was detected at the plasma membrane already at the onset of tooth development in the epithelial cells of the tooth. This pattern remained unaltered during further tooth development. The mesenchymal cells only showed plakoglobin from cytodifferentiation onwards. Plakoglobin 1a morpholino-injected embryos showed normal tooth development with proper initiation and differentiation. Although plakoglobin is clearly present during normal odontogenesis, the loss of plakoglobin 1a does not influence tooth development. β-catenin was found at the cell borders of all cells of the successional lamina but also in the nuclei of surrounding mesenchymal cells. Only membranous, not nuclear, β-catenin, was found during morphogenesis stage. However, during cytodifferentiation stage, both nuclear and membrane-bound β-catenin was detected in the layers of the enamel organ as well as in the differentiating odontoblasts. Nuclear β-catenin is an indication of an activated Wnt pathway, therefore suggesting a possible role for Wnt signalling during zebrafish tooth development and replacement. PMID:26938059

  8. Beta-Catenin and Plakoglobin Expression during Zebrafish Tooth Development and Replacement.

    Directory of Open Access Journals (Sweden)

    Barbara Verstraeten

    Full Text Available We analyzed the protein distribution of two cadherin-associated molecules, plakoglobin and β-catenin, during the different stages of tooth development and tooth replacement in zebrafish. Plakoglobin was detected at the plasma membrane already at the onset of tooth development in the epithelial cells of the tooth. This pattern remained unaltered during further tooth development. The mesenchymal cells only showed plakoglobin from cytodifferentiation onwards. Plakoglobin 1a morpholino-injected embryos showed normal tooth development with proper initiation and differentiation. Although plakoglobin is clearly present during normal odontogenesis, the loss of plakoglobin 1a does not influence tooth development. β-catenin was found at the cell borders of all cells of the successional lamina but also in the nuclei of surrounding mesenchymal cells. Only membranous, not nuclear, β-catenin, was found during morphogenesis stage. However, during cytodifferentiation stage, both nuclear and membrane-bound β-catenin was detected in the layers of the enamel organ as well as in the differentiating odontoblasts. Nuclear β-catenin is an indication of an activated Wnt pathway, therefore suggesting a possible role for Wnt signalling during zebrafish tooth development and replacement.

  9. Brazilian production development of class 2 polymeric surge arresters for transmission line application

    Energy Technology Data Exchange (ETDEWEB)

    Dellallibera, Adriano A. [Industria Eletromecanica Balestro, Mogi Mirim, SP (Brazil)], E-mail: adrianoad@balestro.com; Andrade, Antonio Donizetti de; Bezerra, Ana Cristina Guara; Duarte, Jose Vicente Pereira; Gois, Paulo Marcio Batista; Markiewicz, Rubens Leopoldo [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil)], Emails: andonize@cemig.com.br, anacris@cemig.com.br, vicente@cemig.com.br, pgois@cemig.com.br, rlmark@cemig.com.br

    2007-07-01

    This paper shows the steeps of Brazilian class 2 ZnO lightning surge arrester development and production, aiming to attend the goal of CEMIG transmission lines performance improvement against lightning discharges action. The description of CEMIG transmission lines performance, before and after the ZnO lightning arresters installation, the necessity of use of ZnO lightning surge arrester, the prototypes manufacture, tests, problems and solutions are presented. (author)

  10. Cadmium and zinc reversibly arrest development of Artemia larvae

    Energy Technology Data Exchange (ETDEWEB)

    Bagshaw, J.C.; Rafiee, P.; Matthews, C.O.; MacRae, T.H.

    1986-08-01

    Despite the widespread distribution of heavy metals such as cadmium and zinc in the environment and their well-known cytotoxicity and embryotoxicity in mammals, comparatively little is known about their effect on aquatic organisms, particularly invertebrates. Post-gastrula and early larval development of the brine shrimp, Artemia, present some useful advantages for studies of developmental aspects of environmental toxicology. Dormant encysted gastrulae, erroneously called brine shrimp eggs, can be obtained commercially and raised in the laboratory under completely defined conditions. Following a period of post-gastrula development within the cyst, pre-nauplius larvae emerge through a crack in the cyst shell. A few hours later, free-swimming nauplius larvae hatch. Cadmium is acutely toxic to both adults and nauplius larvae of Artemia, but the reported LC50s are as high as 10 mM, depending on larval age. In this paper the authors show that pre-nauplius larvae prior to hatching are much more sensitive to cadmium than are hatched nauplius larvae. At 0.1 ..mu..m, cadmium retards development and hatching of larvae; higher concentrations block hatching almost completely and thus are lethal. However, the larvae arrested at the emergence stage survive for 24 hours or more before succumbing to the effects of cadmium, and during this period the potentially lethal effect is reversible if the larvae are placed in cadmium-free medium. The effects of zinc parallel those of cadmium, although zinc is somewhat less toxic than cadmium at equal concentrations.

  11. Development of New Type Gap Arrester for Earth Fault Protection in AC Feeding System

    Science.gov (United States)

    Ajiki, Kohji; Morimoto, Hiroaki; Hisamizu, Yasuzi; Kinoshita, Nobuo; Takai, Wataru; Sato, Ryogo

    A gap arrester is being used for ground fault protection in AC Feeding System. However there are faults in which a conventional gap arrester burns down in a normal state of circuit. We investigated the cause of the fault in which a gap arrester burns. Then, it was found out that the cause of the fault was the discharge of AC current from the surge voltage. Therefore, we developed a new type gap arrester which does not burn down. The new type gap arrester is composed of a discharge tube and a zinc oxide element which are connected in series. Unnecessary AC current discharge is prevented by this structure. The new type gap arrester is actually used at the railroad track.

  12. Hedgehog signaling is required at multiple stages of zebrafish tooth development

    OpenAIRE

    Stock David W; Yoo James J; Jackman William R

    2010-01-01

    Abstract Background The accessibility of the developing zebrafish pharyngeal dentition makes it an advantageous system in which to study many aspects of tooth development from early initiation to late morphogenesis. In mammals, hedgehog signaling is known to be essential for multiple stages of odontogenesis; however, potential roles for the pathway during initiation of tooth development or in later morphogenesis are incompletely understood. Results We have identified mRNA expression of the he...

  13. Caspase-7 tooth germ and hair follicle development and maintenance

    Czech Academy of Sciences Publication Activity Database

    Veselá, Barbora; Matalová, Eva

    Rome : ECDO, 2012. 257-257. [Euroconference from Death to Eternity /20./ and Training course on Concepts and Methods in Programmed Cell Death /9./. 14.09.2012-17.09.2012, Rome] R&D Projects: GA ČR(CZ) GAP502/12/1285 Institutional support: RVO:67985904 Keywords : caspase-7 * hair follicle * tooth germ Subject RIV: EA - Cell Biology

  14. Sprouty Genes Control Diastema Tooth Development via Bidirectional Antagonism of Epithelial-Mesenchymal FGF Signaling

    OpenAIRE

    Klein, Ophir D.; Minowada, George; Peterkova, Renata; Kangas, Aapo; Yu, Benjamin D.; Lesot, Herve; Peterka, Miroslav; Jernvall, Jukka; Martin, Gail R.

    2006-01-01

    Unlike humans, who have a continuous row of teeth, mice have only molars and incisors separated by a toothless region called a diastema. Although tooth buds form in the embryonic diastema, they regress and do not develop into teeth. Here, we identify members of the Sprouty (Spry) family, which encode negative feedback regulators of fibroblast growth factor (FGF) and other receptor tyrosine kinase signaling, as genes that repress diastema tooth development. We show that different Sprouty genes...

  15. Semaphorin 3A and Class 4 Semaphorins in Tooth Innervation and Development

    OpenAIRE

    Shrestha, Anjana

    2014-01-01

    Background: Dental trigeminal axon elongation, navigation and patterning occur in a controlled manner that is intimately linked to tooth shape formation and cell differentiation. Development of tooth results from sequential and reciprocal molecular interactions between epithelial and mesenchymal tissues. Semaphorin family of secreted and membrane-bound axonal growth cone guiding molecules regulates the development of the nervous system and also serves important non-neuronal fun...

  16. The development of complex tooth shape in reptiles

    OpenAIRE

    Oldrich eZahradnicek; Marcela eBuchtova; Hana eDosedelova; Abigail Saffron Tucker

    2014-01-01

    Reptiles have a diverse array of tooth shapes, from simple unicuspid to complex multicuspid teeth, reflecting functional adaptation to a variety of diets and eating styles. In addition to cusps, often complex longitudinal labial and lingual enamel crests are widespread and contribute to the final shape of reptile teeth. The simplest shaped unicuspid teeth have been found in piscivorous or carnivorous ancestors of recent diapsid reptiles and they are also present in some extant carnivores such...

  17. Epiprofin-Sp6. A new player in the regulation of tooth development

    OpenAIRE

    Jimenez-Rojo, Lucia; Ibarretxe, Gaskon; Aurrekoetxea, Maitane; de Vega, Susana; Nakamura, Takashi; Yamada, Yoshihiko; Unda, F.

    2010-01-01

    Odontogenesis is governed by a complex network of intercellular signaling events between the dental epithelium and mesenchyme. This network leads to the progressive determination of tooth shape, and to the differentiation of these tissues into enamel-producing ameloblasts and dentin-producing odontoblasts respectively. Among the main signaling pathways involved in the regulation of tooth development, Bone Morphogenetic Protein (BMP), Sonic hedgehog (Shh) and Wingles...

  18. New Developed Cylindrical TM010 Mode EPR Cavity for X-Band In Vivo Tooth Dosimetry

    OpenAIRE

    Junwang, Guo; Qingquan, Yuan; Jianbo, Cong; Lei, Ma; Guofu, Dong; Guoshan, Yang; Ke, Wu

    2014-01-01

    EPR tooth in vivo dosimetry is an attractive approach for initial triage after unexpected nuclear events. An X-band cylindrical TM010 mode resonant cavity was developed for in vivo tooth dosimetry and used in EPR applications for the first time. The cavity had a trapezoidal measuring aperture at the exact position of the cavity’s cylindrical wall where strong microwave magnetic field H1 concentrated and weak microwave electric field E1 distributed. Theoretical calculations and simulations wer...

  19. Differential expression of decorin and biglycan genes during mouse tooth development

    Science.gov (United States)

    Matsuura, T.; Duarte, W. R.; Cheng, H.; Uzawa, K.; Yamauchi, M.

    2001-01-01

    Small leucine-rich proteoglycans (SLRPs) have a number of biological functions and some of them are thought to regulate collagen mineralizaton in bone and tooth. We have previously identified and immunolocalized two members of the SLRPs family, decorin and biglycan, in bovine tooth/periodontium. To investigate their potential roles in tooth development, we examined the mRNA expression patterns of decorin, biglycan and type I collagen in newborn (day 19) mice tooth germs by in situ hybridization. At this developmental stage, the first maxillary and mandibular molars include stages before and after secretion of the predentin matrix, respectively. The expression of decorin mRNA coincided with that of type I collagen mRNA and was mostly observed in secretory odontoblasts, while the biglycan mRNA was expressed throughout the tooth germ, including pre-secretory odontoblasts/ameloblasts, dental papilla and stellate reticulum. However, its signal in secretory odontoblasts was not as evident as that of decorin. In mandibular incisors, where a significant amount of predentin matrix and a small amount of enamel matrix were already secreted, a similar differential expression pattern was observed. In secretory ameloblasts the biglycan mRNA expression was apparent, while that of decorin was not. These differential expression patterns suggest the distinct roles of biglycan and decorin in the process of tooth development.

  20. Arrested development: early prefrontal lesions impair the maturation of moral judgement

    OpenAIRE

    Taber-Thomas, Bradley C.; Asp, Erik W.; Koenigs, Michael; Sutterer, Matthew; Anderson, Steven W; Tranel, Daniel

    2014-01-01

    Atypical moral development is associated with antisocial behavior, but the neural systems required for moral development are unclear. Taber-Thomas, Asp et al. study patients with ventromedial prefrontal cortex lesions acquired during development, and find that such lesions result in arrested moral development, as revealed by an increase in self-interested morality.

  1. Plakophilin-1, a Novel Wnt Signaling Regulator, Is Critical for Tooth Development and Ameloblast Differentiation

    Science.gov (United States)

    Arai, Chieko; Yamada, Aya; Saito, Kan; Ishikawa, Masaki; Xue, Han; Funada, Keita; Haruyama, Naoto; Yamada, Yoshihiko; Fukumoto, Satoshi; Takahashi, Ichiro

    2016-01-01

    Tooth morphogenesis is initiated by reciprocal interactions between the ectoderm and neural crest-derived mesenchyme, and the Wnt signaling pathway is involved in this process. We found that Plakophilin (PKP)1, which is associated with diseases such as ectodermal dysplasia/skin fragility syndrome, was highly expressed in teeth and skin, and was upregulated during tooth development. We hypothesized that PKP1 regulates Wnt signaling via its armadillo repeat domain in a manner similar to β-catenin. To determine its role in tooth development, we performed Pkp1 knockdown experiments using ex vivo organ cultures and cell cultures. Loss of Pkp1 reduced the size of tooth germs and inhibited dental epithelial cell proliferation, which was stimulated by Wnt3a. Furthermore, transfected PKP1-emerald green fluorescent protein was translocated from the plasma membrane to the nucleus upon stimulation with Wnt3a and LiCl, which required the PKP1 N terminus (amino acids 161 to 270). Localization of PKP1, which is known as an adhesion-related desmosome component, shifted to the plasma membrane during ameloblast differentiation. In addition, Pkp1 knockdown disrupted the localization of Zona occludens 1 in tight junctions and inhibited ameloblast differentiation; the two proteins were shown to directly interact by immunoprecipitation. These results implicate the participation of PKP1 in early tooth morphogenesis as an effector of canonical Wnt signaling that controls ameloblast differentiation via regulation of the cell adhesion complex. PMID:27015268

  2. Plakophilin-1, a Novel Wnt Signaling Regulator, Is Critical for Tooth Development and Ameloblast Differentiation.

    Directory of Open Access Journals (Sweden)

    Kanako Miyazaki

    Full Text Available Tooth morphogenesis is initiated by reciprocal interactions between the ectoderm and neural crest-derived mesenchyme, and the Wnt signaling pathway is involved in this process. We found that Plakophilin (PKP1, which is associated with diseases such as ectodermal dysplasia/skin fragility syndrome, was highly expressed in teeth and skin, and was upregulated during tooth development. We hypothesized that PKP1 regulates Wnt signaling via its armadillo repeat domain in a manner similar to β-catenin. To determine its role in tooth development, we performed Pkp1 knockdown experiments using ex vivo organ cultures and cell cultures. Loss of Pkp1 reduced the size of tooth germs and inhibited dental epithelial cell proliferation, which was stimulated by Wnt3a. Furthermore, transfected PKP1-emerald green fluorescent protein was translocated from the plasma membrane to the nucleus upon stimulation with Wnt3a and LiCl, which required the PKP1 N terminus (amino acids 161 to 270. Localization of PKP1, which is known as an adhesion-related desmosome component, shifted to the plasma membrane during ameloblast differentiation. In addition, Pkp1 knockdown disrupted the localization of Zona occludens 1 in tight junctions and inhibited ameloblast differentiation; the two proteins were shown to directly interact by immunoprecipitation. These results implicate the participation of PKP1 in early tooth morphogenesis as an effector of canonical Wnt signaling that controls ameloblast differentiation via regulation of the cell adhesion complex.

  3. A model of growth restraints to explain the development and evolution of tooth shapes in mammals.

    Science.gov (United States)

    Osborn, Jeffrey W

    2008-12-01

    The problem investigated here is control of the development of tooth shape. Cells at the growing soft tissue interface between the ectoderm and mesoderm in a tooth anlage are observed to buckle and fold into a template for the shape of the tooth crown. The final shape is created by enamel secreted onto the folds. The pattern in which the folds develop is generally explained as a response to the pattern in which genes are locally expressed at the interface. This congruence leaves the problem of control unanswered because it does not explain how either pattern is controlled. Obviously, cells are subject to Newton's laws of motion so that mechanical forces and constraints must ultimately cause the movements of cells during tooth morphogenesis. A computer model is used to test the hypothesis that directional resistances to growth of the epithelial part of the interface could account for the shape into which the interface folds. The model starts with a single epithelial cell whose growth is constrained by 4 constant directional resistances (anterior, posterior, medial and lateral). The constraints force the growing epithelium to buckle and fold. By entering into the model different values for these constraints the modeled epithelium is induced to buckle and fold into the different shapes associated with the evolution of a human upper molar from that of a reptilian ancestor. The patterns and sizes of cusps and the sequences in which they develop are all correctly reproduced. The model predicts the changes in the 4 directional constraints necessary to develop and evolve from one tooth shape into another. I conclude more generally expressed genes that control directional resistances to growth, not locally expressed genes, may provide the information for the shape into which a tooth develops. PMID:18838080

  4. Changes in gene-expression during development of the murine molar tooth germ

    OpenAIRE

    2007-01-01

    In a matter of a few days the murine tooth germ develops into a complex, mineralized, structure. Murine 30K microarrays were used to examine gene expression in the mandibular first molar tooth germs isolated at 15.5dpc and at 2DPN. Microarray results were validated using real-time RT-PCR. The results suggested that only 25 genes (3 without known functions) exhibited significantly higher expression at 15.5dpc compared to 2DPN. In contrast, almost 1400 genes exhibited significantly (P

  5. Arrested development of sheep strongyles: onset and resumption under field conditions of Central Europe

    Czech Academy of Sciences Publication Activity Database

    Langrová, I.; Makovcová, K.; Vadlejch, J.; Jankovská, I.; Petrtýl, M.; Fechtner, J.; Keil, P.; Lytvynets, Andrej; Borkovcová, M.

    2008-01-01

    Roč. 103, č. 2 (2008), s. 387-392. ISSN 0932-0113 Institutional research plan: CEZ:AV0Z50110509 Keywords : arrested development * gastrointestinal nematodes * sheep Subject RIV: EG - Zoology Impact factor: 1.473, year: 2008

  6. Cell cycle arrest by a gradient of Dpp signaling during Drosophila eye development

    Directory of Open Access Journals (Sweden)

    Bhattacharya Abhishek

    2010-03-01

    Full Text Available Abstract Background The secreted morphogen Dpp plays important roles in spatial regulation of gene expression and cell cycle progression in the developing Drosophila eye. Dpp signaling is required for timely cell cycle arrest ahead of the morphogenetic furrow as a prelude to differentiation, and is also important for eye disc growth. The dpp gene is expressed at multiple locations in the eye imaginal disc, including the morphogenetic furrow that sweeps across the eye disc as differentiation initiates. Results Studies of Brinker and Dad expression, and of Mad phosphorylation, establish that there is a gradient of Dpp signaling in the eye imaginal disc anterior to the morphogenetic furrow, predominantly in the anterior-posterior axis, and also Dpp signaling at the margins of the disc epithelium and in the dorsal peripodial membrane. Almost all signaling activity seems to spread through the plane of the epithelia, although peripodial epithelium cells can also respond to underlying disc cells. There is a graded requirement for Dpp signaling components for G1 arrest in the eye disc, with more stringent requirements further anteriorly where signaling is lower. The signaling level defines the cell cycle response, because elevated signaling through expression of an activated Thickveins receptor molecule arrested cells at more anterior locations. Very anterior regions of the eye disc were not arrested in response to activated receptor, however, and evidence is presented that expression of the Homothorax protein may contribute to this protection. By contrast to activated Thickveins, ectopic expression of processed Dpp leads to very high levels of Mad phosphorylation which appear to have non-physiological consequences. Conclusions G1 arrest occurs at a threshold level of Dpp signaling within a morphogen gradient in the anterior eye. G1 arrest is specific for one competent domain in the eye disc, allowing Dpp signaling to promote growth at earlier

  7. Patterns of Glycoconjugate Distribution during Molar Tooth Germ Development in Mice

    Directory of Open Access Journals (Sweden)

    AR. Varasteh

    2007-09-01

    Full Text Available Objective: The aim of the present study was to evaluate the structure and distribution of Glycoconjugates during molar tooth germ development in mice.Materials and Methods: Sixteen tooth germs were obtained from BALB/c mice embryos 15 to 18 days post-gestation and fixed in 10% formalin. After routine tissue processing, 5μm sections were cut and stained with BSA1-B4 and PNA using the lectin histochemical method. All slides were evaluated by light microscopy.Results: Both lectins showed positive reaction in the tooth germ but with spatiotemporal differences. During bell stage, the reaction was strong with BSA1-B4 but moderate with PNA. Strong PNA uptake was observed in the odontoblastic and ameloblastic nuclei alongwith the apical cytoplasm of the ameloblasts.Conclusion: Although the lectins that were used in the present study recognize the same terminal sugar residue, they reacted with different disaccharide sequences with various penaltomer sugars. Therefore it may be assumed that the pattern of affinity for different parts of the developing tooth germ such as ameloblasts and odontoblasts is different in various lectins.

  8. Complex Systems Analysis of Arrested Neural Cell Differentiation during Development and Analogous Cell Cycling Models in Carcinogenesis

    OpenAIRE

    Baianu, Professor I.C.; Prisecaru, M.S. V

    2004-01-01

    A new approach to the modular, complex systems analysis of nonlinear dynamics of arrested neural cell Differentiation--induced cell proliferation during organismic development and the analogous cell cycling network transformations involved in carcinogenesis is proposed. Neural tissue arrested differentiation that induces cell proliferation during perturbed development and Carcinogenesis are complex processes that involve dynamically inter-connected biomolecules in the intercellular, membrane...

  9. The role of peer arrests on the development of youths' attitudes towards the justice system.

    Science.gov (United States)

    Fine, Adam; Cavanagh, Caitlin; Donley, Sachiko; Steinberg, Laurence; Frick, Paul J; Cauffman, Elizabeth

    2016-04-01

    During adolescence, youths develop attitudes about the justice system. Although there is consistent evidence that personal experiences with legal actors contribute to attitudes toward the justice system, adolescents' attitudes may also be influenced vicariously through their friends' experiences with the justice system. Using data from a sample of 1,216 first-time male adolescent offenders, the present study examines how attitudes toward the justice system develop over 24 months following the adolescent's first arrest. Even after accounting for personal justice system experiences, including self-reported offending, time on the streets, and contacts with the police, results indicate that adolescents with friends who were arrested report more negative attitudes toward the justice system than those without friends who were arrested. Further, experiencing a friend's arrest has a larger impact on the attitudes of youths who are experiencing it for the first time. We provide evidence that attitudes toward the justice system are a product of accumulated social experiences-both personal and vicarious-with the justice system. (PsycINFO Database Record PMID:26595702

  10. Study of Glycosaminoglycans of Extracellular Matrix (ECM) in Pulp of Developing Tooth

    OpenAIRE

    Kermany T; AR. Varasteh; Nicravesh MR; oradi M

    2000-01-01

    Mesenchymal- epithelial interactions during embryogenesis have been shown to be important in the fetal development of many organs. Identification of molecules that modulate these interactions is key to our understanding of the pathological conditions. The major groups of extracellular matrix (ECM) molecules characterized are glycosaminoglycans that candidate for morphogenesis and differentiation of ceils and tissues. In this study the molecules of ECM were considered in tooth development, pre...

  11. Tooth extraction

    Science.gov (United States)

    A tooth extraction is a procedure to remove a tooth from the gum socket. It is usually done by a general ... gum. If you need a more complex tooth extraction: You will be given sedation so you are ...

  12. CD 95 mediated apoptosis in embryogenesis: implication in tooth development.

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Šetková, Jana; Blackburn, J.; Míšek, Ivan; Sharpe, P. T.

    2006-01-01

    Roč. 9, 3 (2006), s. 123-128. ISSN 1397-5927 R&D Projects: GA ČR GA304/04/0101; GA MŠk OC B23.001 Institutional research plan: CEZ:AV0Z50450515 Keywords : fas * embryonic development * odontogenesis Subject RIV: EB - Genetics ; Molecular Biology

  13. Laser capture microdissection enables cellular and molecular studies of tooth root development

    OpenAIRE

    Sun, Jian-Xun; Horst, Orapin V; Bumgarner, Roger; Lakely, Bryce; Somerman, Martha J; Zhang, Hai

    2012-01-01

    Epithelial–mesenchymal interactions (EMIs) are critical for tooth development. Molecular mechanisms mediating these interactions in root formation is not well understood. Laser capture microdissection (LCM) and subsequent microarray analyses enable large scale in situ molecular and cellular studies of root formation but to date have been hindered by technical challenges of gaining intact histological sections of non-decalcified mineralized teeth or jaws with well-preserved RNA. Here,we descri...

  14. Minipig embryo-suitable model for an early tooth development investigation

    Czech Academy of Sciences Publication Activity Database

    Štembírek, Jan; Buchtová, Marcela; Matalová, Eva; Míšek, Ivan

    Plzeň, 2009. s. 152-152. [Morphology 2009. 45th International Congress on Anatomy and 46th Lojda symposium on Histochemy. 07.09.2009-09.09.2009, Plzeň] R&D Projects: GA AV ČR IAA600450904; GA ČR GC524/08/J032 Institutional research plan: CEZ:AV0Z50450515 Keywords : minipig * tooth development Subject RIV: EA - Cell Biology

  15. Spatiotemporal expression of caveolin-1 and EMMPRIN during mouse tooth development.

    Science.gov (United States)

    Shi, Lu; Li, Lingyun; Wang, Ding; Li, Shu; Chen, Zhi; An, Zhengwen

    2016-06-01

    Caveolin-1 is a scaffolding protein involved in the formation of cholesterol-rich caveolae lipid rafts within the plasma membrane and is capable of collecting signaling molecules into the caveolae and regulating their activity, including extracellular matrix metalloproteinase inducer (EMMPRIN). However, detailed expression patterns of caveolin-1 and EMMPRIN in the developing dental germ are largely unknown. The present study investigated the expression patterns of caveolin-1 and EMMPRIN in the developing mouse tooth germ by immunohistochemistry and real-time polymerase chain reaction. At the bud stage, caveolin-1 expression was initiated in the epithelium bud and mesenchymal cells, while EMMPRIN was weakly expressed at this stage. At the cap stage, caveolin-1 protein was located in the lingual part of the tooth germ; however, EMMPRIN protein was located in the labial part. From the bell stage to 2 days postnatal, caveolin-1 expression was detected in the ameloblasts and cervical loop area; with EMMPRIN expression in the ameloblasts and odontoblasts. Real-time polymerase chain reaction results showed that both caveolin-1 and EMMPRIN mRNA levels increased gradually with progression of developmental stages, and peaked at day two postnatal. The current finding suggests that both caveolin-1 and EMMPRIN take part in mouse tooth development, especially in the differentiation and organization of odontogenic tissues. PMID:27075451

  16. Development of a theoretical guide for nursing care in cardiac arrest

    Directory of Open Access Journals (Sweden)

    Aliandra Bittencourt da Silva

    2013-11-01

    Full Text Available This study aimed to identify the knowledge on cardiorespiratory arrest among nurses in a hospital of Vale do Paraíba, São Paulo, Brazil, and develop a theoretical guide for care of this emergency. We prepared an instrument of data collection based on relevant literature and the 2010 AHA Guidelines for CPR, from August to October 2012. The sample consisted of 41 nurses who deliver care activities in various units of the hospital. The study showed that professional participants said they were able to act in cardiopulmonary resuscitation, however, there were limitations of knowledge about the theme. Given the above, we developed a theoretical guide for cardiac arrest care based on scientific literature and covering questions submitted by nurses.

  17. Heavy-Section Steel Technology Program: Recent developments in crack initiation and arrest research

    International Nuclear Information System (INIS)

    Technology for the analysis of crack initiation and arrest is central to the reactor pressure vessel fracture-margin-assessment process. Regulatory procedures for nuclear plants utilize this technology to assure the retention of adequate fracture-prevention margins throughout the plant operating license period. As nuclear plants age and regulatory procedures dictate that fracture-margin assessments be performed, interest in the fracture-mechanics technology incorporated into those procedures has heightened. This has led to proposals from a number of sources for development and refinement of the underlying crack-initiation and arrest-analysis technology. An important element of the Heavy-Section Steel Technology (HSST) Program is devoted to the investigation and evaluation of these proposals. This paper presents the technological bases and fracture-margin assessment objectives for some of the recently proposed crack-initiation and arrest-technology developments. The HSST Program approach to the evaluation of the proposals is described and the results and conclusions obtained to date are presented

  18. Development of dental charts according to tooth development and eruption for Turkish children and young adults

    Energy Technology Data Exchange (ETDEWEB)

    Karadayl, Beytullah; Ozaslan, Abdi [University of Istanbul, Cerrahpasa Faculty of Medicine, Forensic Medicine Department, Istanbul (Turkey); Afsin, Hueseyin [University of Istanbul, Cerrahpasa Faculty of Medicine, Forensic Medicine Department, Istanbul (Turkey); Karadayi, Suekriye [Public Health Agency, Istanbul (Turkey)

    2014-06-15

    In this study, we aimed to develop dental charts for Turkish children and young adults of both genders within the age group of 4.5-22.5 years according to tooth mineralization and eruption in a format similar to that proposed by AlQahtani et al. In total, 753 digital panoramic radiographs from 350 males and 403 females were assessed. The permanent teeth were evaluated according to the classification system described by Demirjian et al. The eruption stage was assessed with Bengston's system, which was modified by AlQahtani et al at four points. Teeth generally developed earlier in females than in males. This was particularly notable in the age group of 5-14 years. However, this difference was usually visible in only one stage, not in all teeth. It has been determined that the mixed dentition period ended with the shedding of the second deciduous molars in both genders. The dental charts presented here included information that could be beneficial to dental clinicians in making appropriate diagnosis and planning orthodontic and surgical procedures. These charts also provided datasets for preliminary dental age estimation in Turkish children and young adults.

  19. Development of dental charts according to tooth development and eruption for Turkish children and young adults

    International Nuclear Information System (INIS)

    In this study, we aimed to develop dental charts for Turkish children and young adults of both genders within the age group of 4.5-22.5 years according to tooth mineralization and eruption in a format similar to that proposed by AlQahtani et al. In total, 753 digital panoramic radiographs from 350 males and 403 females were assessed. The permanent teeth were evaluated according to the classification system described by Demirjian et al. The eruption stage was assessed with Bengston's system, which was modified by AlQahtani et al at four points. Teeth generally developed earlier in females than in males. This was particularly notable in the age group of 5-14 years. However, this difference was usually visible in only one stage, not in all teeth. It has been determined that the mixed dentition period ended with the shedding of the second deciduous molars in both genders. The dental charts presented here included information that could be beneficial to dental clinicians in making appropriate diagnosis and planning orthodontic and surgical procedures. These charts also provided datasets for preliminary dental age estimation in Turkish children and young adults.

  20. Tooth abscess

    Science.gov (United States)

    ... your teeth, mouth, and gums. You may have pain when the dentist taps the tooth. Biting or closing the mouth tightly also increases ... abscess; Dental abscess; Tooth infection; Abscess - tooth Images Tooth anatomy References Amsterdam JT. Oral Medicine. In: Marx JA, Hockberger RS, Walls RM, et ...

  1. Exogenous FGF8 rescues development of mouse diastemal vestigial tooth ex vivo

    OpenAIRE

    Li, Lu; Yuan, Guohua; Liu, Chao; Zhang, Lu; Zhang, Yanding; Chen, Yiping; Chen, Zhi

    2011-01-01

    Regression of vestigial tooth buds results in the formation of the toothless diastema, a unique feature of the mouse dentition. Revitalization of the diastemal vestigial tooth bud provides an excellent model for studying tooth regeneration and replacement. It was shown previously that suppression of FGF signaling in the diastema is a causative of vestigial tooth bud regression. In this study, we report that application of exogenous FGF8 to the mouse embryonic diastemal region rescues diastema...

  2. Osteoadherin accumulates in the predentin towards the mineralization front in the developing tooth.

    Directory of Open Access Journals (Sweden)

    Hero Nikdin

    Full Text Available BACKGROUND: Proteoglycans (PG are known to be involved in the organization and assembly of the extracellular matrix (ECM prior to mineral deposition. Osteoadherin (OSAD, a keratan sulphate PG is a member of the small leucine-rich (SLRP family of PGs and unlike other SLRPs, OSAD expression is restricted to mineralized tissues. It is proposed to have a high affinity for hydroxyapatite and has been shown to be expressed by mature osteoblasts but its exact role remains to be elucidated. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the protein distribution of OSAD in the developing mouse tooth using immunohistochemistry and compared its expression with other SLRPs, biglycan (BGN, decorin (DCN and fibromodulin (FMD. OSAD was found to be specifically localized in the predentin layer of the tooth and focused at the mineralization front. These studies were confirmed at the ultrastructural level using electron microscopy (iEM, where the distribution of immunogold labeled OSAD particles were quantified and significant amounts were found in the predentin, forming a gradient towards the mineralization front. In addition, iEM results revealed OSAD to lie in close association with collagen fibers, further suggesting an important role for OSAD in the organization of the ECM. The expression profile of mineralization-related SLRP genes by rat dental pulp cells exposed to mineralization inducing factors, showed an increase in all SLRP genes. Indeed, OSAD expression was significantly increased during the mineralization process, specifically following, matrix maturation, and finally mineral deposition. Alizarin Red S staining for calcium deposition showed clear bone-like nodules, which support matrix maturation and mineralization. CONCLUSIONS: These studies provide new evidence for the role of OSAD in the mineralization process and its specific localization in the predentin layer accumulating at the mineralization front highlighting its role in tooth development.

  3. FHL2 mediates tooth development and human dental pulp cell differentiation into odontoblasts, partially by interacting with Runx2.

    Science.gov (United States)

    Du, Jianxin; Wang, Qiang; Yang, Pishan; Wang, Xiaoying

    2016-04-01

    The differentiation of mesenchymal cells in tooth germ and dental pulp cells into odontoblasts is crucial for dentin formation, and the transcription factor runt-related transcription factor (Runx2) is necessary for odontoblast differentiation. Our previous study demonstrated that four and a half LIM domains 2 (FHL2) may play an important role in tooth development and human dental pulp cell differentiation. This study aimed to determine whether FHL2 mediated the mesenchymal cells in tooth development and human dental pulp cell differentiation into odontoblasts by interacting with Runx2. The expression patterns of FHL2 and Runx2 were examined at the early stages of mouse molar development using double immunofluorescence staining. Western blot analysis and co-immunoprecipitation (Co-IP) were conducted for the preliminary study of the relationship between FHL2 and Runx2 in human dental pulp cell differentiation into odontoblasts. Results of double immunofluorescence staining showed that FHL2 and Runx2 exhibited similar expression patterns at the early stages of tooth development. Western blot analysis indicated that the expression patterns of FHL2 and Runx2 were synchronized on day 7 of induction, whereas those on day 14 differed. Co-IP analysis revealed positive bands of protein complexes, revealing the interaction of FHL2 and Runx2 on days 0, 7 and 14 of induction. Our data suggested that FHL2 might interact with Runx2 to mediate mesenchymal cell differentiation at the early stages of tooth development and human dental pulp cell differentiation. PMID:26759258

  4. Tooth anatomy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002214.htm Tooth anatomy To use the sharing features on this page, ... upper jawbone is called the maxilla. Images Tooth anatomy References Lingen MW. Head and neck. In: Kumar ...

  5. Limb, tooth, beak: three modes of development and evolutionary innovation of form.

    Science.gov (United States)

    Linde-Medina, Marta; Newman, Stuart A

    2014-04-01

    The standard model of evolutionary change of form, deriving from Darwin's theory via the Modern Synthesis, assumes a gradualistic reshaping of anatomical structures, with major changes only occurring by many cycles of natural selection for marginal adaptive advantage. This model, with its assertion that a single mechanism underlies both micro- and macroevolutionary change, contains an implicit notion of development which is only applicable in some cases. Here we compare the embryological processes that shape the vertebrate limb bud, the mammalian tooth and the avian beak. The implied notion of development in the standard evolutionary picture is met only in the case of the vertebrate limb, a single-primordium organ with morphostatic shaping, in which cells rearrange in response to signalling centres which are essentially unchanged by cell movement. In the case of the tooth, a single-primordium organ with morphodynamic shaping in which the strengths and relationships between signalling centres is influenced by the cell and tissue movements they induce, and the beak, in which the final form is influenced by the collision and rearrangement of multiple tissue primordia, abrupt appearance of qualitatively different forms (i.e. morphological novelties) can occur with small changes in system parameters induced by a genetic change, or by an environmental factor whose effects can be subsequently canalized genetically. Bringing developmental mechanisms and, specifically, the material properties of tissues as excitable media into the evolutionary picture, demonstrates that gradualistic change for incremental adaptive advantage is only one of the possible modes of morphological evolution. PMID:24736155

  6. Limb, tooth, beak: Three modes of development and evolutionary innovation of form

    Indian Academy of Sciences (India)

    Marta Linde-Medina; Stuart A Newman

    2014-04-01

    The standard model of evolutionary change of form, deriving from Darwin’s theory via the Modern Synthesis, assumes a gradualistic reshaping of anatomical structures, with major changes only occurring by many cycles of natural selection for marginal adaptive advantage. This model, with its assertion that a single mechanism underlies both micro- and macroevolutionary change, contains an implicit notion of development which is only applicable in some cases. Here we compare the embryological processes that shape the vertebrate limb bud, the mammalian tooth and the avian beak. The implied notion of development in the standard evolutionary picture is met only in the case of the vertebrate limb, a single-primordium organ with morphostatic shaping, in which cells rearrange in response to signalling centres which are essentially unchanged by cell movement. In the case of the tooth, a single-primordium organ with morphodynamic shaping in which the strengths and relationships between signalling centres is influenced by the cell and tissue movements they induce, and the beak, in which the final form is influenced by the collision and rearrangement of multiple tissue primordia, abrupt appearance of qualitatively different forms (i.e. morphological novelties) can occur with small changes in system parameters induced by a genetic change, or by an environmental factor whose effects can be subsequently canalized genetically. Bringing developmental mechanisms and, specifically, the material properties of tissues as excitable media into the evolutionary picture, demonstrates that gradualistic change for incremental adaptive advantage is only one of the possible modes of morphological evolution.

  7. New developed cylindrical TM010 mode EPR cavity for X-band in vivo tooth dosimetry.

    Directory of Open Access Journals (Sweden)

    Guo Junwang

    Full Text Available EPR tooth in vivo dosimetry is an attractive approach for initial triage after unexpected nuclear events. An X-band cylindrical TM010 mode resonant cavity was developed for in vivo tooth dosimetry and used in EPR applications for the first time. The cavity had a trapezoidal measuring aperture at the exact position of the cavity's cylindrical wall where strong microwave magnetic field H1 concentrated and weak microwave electric field E1 distributed. Theoretical calculations and simulations were used to design and optimize the cavity parameters. The cavity features were evaluated by measuring DPPH sample, intact incisor samples embed in a gum model and the rhesus monkey teeth. The results showed that the cavity worked at designed frequency and had the ability to make EPR spectroscopy in relative high sensitivity. Sufficient modulation amplitude and microwave power could be applied into the aperture. Radiation induced EPR signal could be observed remarkably from 1 Gy irradiated intact incisor within only 30 seconds, which was among the best in scan time and detection limit. The in vivo spectroscopy was also realized by acquiring the radiation induced EPR signal from teeth of rhesus monkey whose teeth was irradiated by dose of 2 Gy. The results suggested that the cavity was sensitive to meet the demand to assess doses of significant level in short time. This cavity provided a very potential option for the development of X-band in vivo dosimetry.

  8. New developed cylindrical TM010 mode EPR cavity for X-band in vivo tooth dosimetry.

    Science.gov (United States)

    Junwang, Guo; Qingquan, Yuan; Jianbo, Cong; Lei, Ma; Guofu, Dong; Guoshan, Yang; Ke, Wu

    2014-01-01

    EPR tooth in vivo dosimetry is an attractive approach for initial triage after unexpected nuclear events. An X-band cylindrical TM010 mode resonant cavity was developed for in vivo tooth dosimetry and used in EPR applications for the first time. The cavity had a trapezoidal measuring aperture at the exact position of the cavity's cylindrical wall where strong microwave magnetic field H1 concentrated and weak microwave electric field E1 distributed. Theoretical calculations and simulations were used to design and optimize the cavity parameters. The cavity features were evaluated by measuring DPPH sample, intact incisor samples embed in a gum model and the rhesus monkey teeth. The results showed that the cavity worked at designed frequency and had the ability to make EPR spectroscopy in relative high sensitivity. Sufficient modulation amplitude and microwave power could be applied into the aperture. Radiation induced EPR signal could be observed remarkably from 1 Gy irradiated intact incisor within only 30 seconds, which was among the best in scan time and detection limit. The in vivo spectroscopy was also realized by acquiring the radiation induced EPR signal from teeth of rhesus monkey whose teeth was irradiated by dose of 2 Gy. The results suggested that the cavity was sensitive to meet the demand to assess doses of significant level in short time. This cavity provided a very potential option for the development of X-band in vivo dosimetry. PMID:25222483

  9. Impairment of Bony Crypt Development Associated With Hexavalent Chromium Exposure During Tooth Eruption.

    Science.gov (United States)

    Sánchez, Luciana M; Lewicki, Marianela; De Lucca, Romina C; Ubios, Ángela M

    2015-12-01

    Improperly treated hexavalent chromium-containing industrial wastes contaminate drinking water, potentially affecting children taking breast milk or baby bottles prepared with infant formula. Thus, the aim of the present work was to determine the effect of this toxic on bone activity in the developing alveolus during tooth eruption of suckling Wistar rats intoxicated with potassium dichromate. Experimental animals received a daily dose of 12.5mg/kg body weight of potassium dichromate by gavage for 10 days; controls received an equivalent volume of saline solution. Histologic and histomorphometric studies of the mandible were performed. The data were statistically analyzed using Student's t test; statistical significance was set at a value of p hexavalent chromium is the result of a lower rate of bone remodeling in the developing alveolus. The obtained results show the importance of controlling toxic substances in drinking water, since their effects may alter the growth and development of subjects who were exposed during early infancy. PMID:27095619

  10. Signi fi cance of Neural Crest in Tooth Development: The Molecular Signature

    Directory of Open Access Journals (Sweden)

    VP Jayasekharan

    2014-07-01

    Full Text Available The neural crest originates from cells located along the lateral margins of the neural plate. Neural crest cells arise as the result of an inductive action by the non-neural ectoderm adjacent to the neural plate and possibly by nearby mesoderm as well. As the neural tube forms, a group of cells separate from the neuro- ectoderm. These cells have the capacity to migrate and differen- tiate extensively within the developing embryo and they are the basis of structures such as spinal sensory ganglia, sympathetic neurons, Schwann cells, pigment cells and meninges. Speci fi c interactions occur during the development of tooth and recent research has concentrated more on the molecular aspects of these interactions. Thus, it is highly imperative to understand and digress the complex mechanisms involved in these processes

  11. Esthetic and endosurgical management of turner′s hypoplasia; a sequlae of trauma to developing tooth germ

    Directory of Open Access Journals (Sweden)

    Bhushan B

    2008-12-01

    Full Text Available Turner′s hypoplasia usually manifests as a portion of missing or diminished enamel, generally affecting one or more permanent teeth in the oral cavity. A case report of 8 year old girl who met with trauma at 2 years of age leading to primary incisors being knocked out, reported after 6 years with complaint of pain and discharge in her anterior malformed teeth is discussed in this article. The permanent incisors erupted with dilacerated crown, root malformations and missing enamel. Further, patient developed sinus, lateral root pathology, tooth mobility and malocclusion in relation to affected teeth which were managed by esthetic, functional, endodontic and surgical procedure. Root canal treatment along with palatal contouring and esthetic restoration by light cure composite was performed on the tooth with crown dilaceration and sinus, where as surgical management was considered for the tooth with root malformation.

  12. Bone morphogenetic protein-2 gene controls tooth root development in coordination with formation of the periodontium

    Institute of Scientific and Technical Information of China (English)

    Audrey Rakian; Wu-Chen Yang; Jelica Gluhak-Heinrich; Yong Cui; Marie A Harris; Demitri Villarreal; Jerry Q Feng; Mary MacDougall; Stephen E Harris

    2013-01-01

    Formation of the periodontium begins following onset of tooth-root formation in a coordinated manner after birth. Dental follicle progenitor cells are thought to form the cementum, alveolar bone and Sharpey’s fibers of the periodontal ligament (PDL). However, little is known about the regulatory morphogens that control differentiation and function of these progenitor cells, as well as the progenitor cells involved in crown and root formation. We investigated the role of bone morphogenetic protein-2 (Bmp2) in these processes by the conditional removal of the Bmp2 gene using the Sp7-Cre-EGFP mouse model. Sp7-Cre-EGFP first becomes active at E18 in the first molar, with robust Cre activity at postnatal day 0 (P0), followed by Cre activity in the second molar, which occurs after P0. There is robust Cre activity in the periodontium and third molars by 2 weeks of age. When the Bmp2 gene is removed from Sp71 (Osterix1) cells, major defects are noted in root, cellular cementum and periodontium formation. First, there are major cell autonomous defects in root-odontoblast terminal differentiation. Second, there are major alterations in formation of the PDLs and cellular cementum, correlated with decreased nuclear factor IC (Nfic), periostin and a-SMA1 cells. Third, there is a failure to produce vascular endothelial growth factor A (VEGF-A) in the periodontium and the pulp leading to decreased formation of the microvascular and associated candidate stem cells in the Bmp2-cKOSp7-Cre-EGFP. Fourth, ameloblast function and enamel formation are indirectly altered in the Bmp2-cKOSp7-Cre-EGFP. These data demonstrate that the Bmp2 gene has complex roles in postnatal tooth development and periodontium formation.

  13. The timing of tooth eruption and root development of permanent canine and premolars in Korean children

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the timing and sequence of eruption of permanent canine and premolars, and to evaluate tooth calcification stage on emergence in Korean children. The sample was comprised of 1,266 children (male 720, female 546) aged from 7-13 years. Tooth eruption and calcification stages were determined through oral and panoramic radiographic examination, respectively. Probit analysis was used to calculate the timing of tooth eruption and tooth calcification stage from these cross-sectional data. In both males and females, eruption occurred around the time when one third of tooth root or more was formed. The sequence was as follows: first premolar, canine, and second premolar in maxilla, and canine, first premolar and second premolar in mandible. Tooth eruption occurred earlier in girls compared with boys, averaging 0.63 years. Eruption sequence is identical in males and females with a trend for females to erupt earlier than males. Tooth eruption becomes earlier over the past decades in Korean children.

  14. The timing of tooth eruption and root development of permanent canine and premolars in Korean children

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Chang Shin; Jung, Yun Hoa; Cho, Bong Hae [Department of Oral and Maxillofacial Radiology, School of Dentistry, Pusan National University, Pusan (Korea, Republic of)

    2010-09-15

    The aim of this study was to investigate the timing and sequence of eruption of permanent canine and premolars, and to evaluate tooth calcification stage on emergence in Korean children. The sample was comprised of 1,266 children (male 720, female 546) aged from 7-13 years. Tooth eruption and calcification stages were determined through oral and panoramic radiographic examination, respectively. Probit analysis was used to calculate the timing of tooth eruption and tooth calcification stage from these cross-sectional data. In both males and females, eruption occurred around the time when one third of tooth root or more was formed. The sequence was as follows: first premolar, canine, and second premolar in maxilla, and canine, first premolar and second premolar in mandible. Tooth eruption occurred earlier in girls compared with boys, averaging 0.63 years. Eruption sequence is identical in males and females with a trend for females to erupt earlier than males. Tooth eruption becomes earlier over the past decades in Korean children.

  15. Canopy shade causes a rapid and transient arrest in leaf development through auxin-induced cytokinin oxidase activity.

    Science.gov (United States)

    Carabelli, Monica; Possenti, Marco; Sessa, Giovanna; Ciolfi, Andrea; Sassi, Massimiliano; Morelli, Giorgio; Ruberti, Ida

    2007-08-01

    A plant grown under canopies perceives the reduction in the ratio of red (R) to far-red (FR) light as a warning of competition, and enhances elongation growth in an attempt to overgrow its neighbors. Here, we report that the same low R/FR signal that induces hypocotyl elongation also triggers a rapid arrest of leaf primordium growth, ensuring that plant resources are redirected into extension growth. The growth arrest induced by low R/FR depends on auxin-induced cytokinin breakdown in incipient vein cells of developing primordia, thus demonstrating the existence of a previously unrecognized regulatory circuit underlying plant response to canopy shade. PMID:17671088

  16. Developing a Corticopuncture system to accelerate the rate of tooth movement

    OpenAIRE

    Mostafa, Mohamed Moharam

    2014-01-01

    Introduction:Tooth movement is caused by inflammatory and cellular reactions within the bone in response to applied orthodontic forces. Several attempts have been made to increase the rate of bone turnover in order to achieve accelerated tooth movement. These attempts can be classified into two categories: physical trauma (such as Alveolar Corticotomy "Wilckodontics", Piezopuncture, Laser and Resonance Vibrations) and application of drugs (such as the systemic and local application of Vitami...

  17. Development of a viscoplastic dynamic fracture mechanics treatment for crack arrest predictions in a PTS event

    International Nuclear Information System (INIS)

    The objective of this research is to develop a fundamentally correct methodology for the prediction of crack arrest at the high upper shelf conditions occurring in a postulated pressurized thermal shock (PTS) event. The effort is aimed at the development of a versatile finite-element method for the solution of time-dependent boundary value problems that admit inertia effects, a prescribed spatial temperature distribution, and viscoplastic constitutive and fracture behavior. Supporting this development are (1) material characterization and fracture experimentation, (2) detailed mathematical analyses of the near-tip region, (3) elastodynamic fracture analysis, and (4) elastic-plastic tearing instability analyses. As a first step, dynamic-viscoplastic analyses are currently being made of the wide plate tests being performed by the National Bureau of Standards in a companion HSST program. Some preliminary conclusions drawn from this work and from the supporting research activities are offered in this paper. The outstanding critical issues that subsequent research must focus on are also described

  18. Study of Glycosaminoglycans of Extracellular Matrix (ECM in Pulp of Developing Tooth

    Directory of Open Access Journals (Sweden)

    Kermany T

    2000-05-01

    Full Text Available Mesenchymal- epithelial interactions during embryogenesis have been shown to be important in the fetal development of many organs. Identification of molecules that modulate these interactions is key to our understanding of the pathological conditions. The major groups of extracellular matrix (ECM molecules characterized are glycosaminoglycans that candidate for morphogenesis and differentiation of ceils and tissues. In this study the molecules of ECM were considered in tooth development, pregnant female mice of balb-c were stained (vaginal plug=0 day and embryos (E12-E19 and newborns (PN1-PN9 were collected. Tissues were fixed, processed embedded and sectioned. Sections were stained with the following methods: Alcian Blue (pH=l, PAS-Alcian Blue (pH=2.5, Aician Blue(pH=5.8 prepared with for MgCL2 concentrations (CEC1- CEC4 and toluidin Blue. Non- parametric statistical test (Kruskall- Wallis showed significant difference between groups from the point of hyaluronic acid, chondroitin sulfate, carboxylated and sulfated glycosaminoglycan in pulp. It seems that the synthesis and secretion of components of ECM is important in morphogenic events and followed by a spatiotemporal pattern and developmentally regulated.

  19. Towards the Automated Analysis and Database Development of Defibrillator Data from Cardiac Arrest

    Directory of Open Access Journals (Sweden)

    Trygve Eftestøl

    2014-01-01

    Full Text Available Background. During resuscitation of cardiac arrest victims a variety of information in electronic format is recorded as part of the documentation of the patient care contact and in order to be provided for case review for quality improvement. Such review requires considerable effort and resources. There is also the problem of interobserver effects. Objective. We show that it is possible to efficiently analyze resuscitation episodes automatically using a minimal set of the available information. Methods and Results. A minimal set of variables is defined which describe therapeutic events (compression sequences and defibrillations and corresponding patient response events (annotated rhythm transitions. From this a state sequence representation of the resuscitation episode is constructed and an algorithm is developed for reasoning with this representation and extract review variables automatically. As a case study, the method is applied to the data abstraction process used in the King County EMS. The automatically generated variables are compared to the original ones with accuracies ≥90% for 18 variables and ≥85% for the remaining four variables. Conclusions. It is possible to use the information present in the CPR process data recorded by the AED along with rhythm and chest compression annotations to automate the episode review.

  20. Hyaluronan in human deciduous tooth germs in the bell stage. Histochemistry and immunohistochemistry

    DEFF Research Database (Denmark)

    Matthiessen, Martin Ebbe; Garbarsch, Charly; Olsen, Birgitte Engelbrecht;

    1997-01-01

    Anatomy, development, glycosaminoglycans, hyaluronan, tooth germs, histochemistry, immunocytochemistry......Anatomy, development, glycosaminoglycans, hyaluronan, tooth germs, histochemistry, immunocytochemistry...

  1. Daily Arrests

    Data.gov (United States)

    Montgomery County of Maryland — This dataset provides the public with arrest information from the Montgomery County Central Processing Unit (CPU) systems. The data presented is derived from every...

  2. Tooth Problems

    Science.gov (United States)

    ... to determine if you need to see your dentist right away. SYMPTOMS DIAGNOSIS SELF-CARE Begin Here ... You have TOOTH LOSS. DENTAL EMERGENCY See your dentist or go to the emergency room right away. ...

  3. Interaction between fibronectin and β1 integrin is essential for tooth development.

    Directory of Open Access Journals (Sweden)

    Kan Saito

    Full Text Available The dental epithelium and extracellular matrix interact to ensure that cell growth and differentiation lead to the formation of teeth of appropriate size and quality. To determine the role of fibronectin in differentiation of the dental epithelium and tooth formation, we analyzed its expression in developing incisors. Fibronectin mRNA was expressed during the presecretory stage in developing dental epithelium, decreased in the secretory and early maturation stages, and then reappeared during the late maturation stage. The binding of dental epithelial cells derived from postnatal day-1 molars to a fibronectin-coated dish was inhibited by the RGD but not RAD peptide, and by a β1 integrin-neutralizing antibody, suggesting that fibronectin-β1 integrin interactions contribute to dental epithelial-cell binding. Because fibronectin and β1 integrin are highly expressed in the dental mesenchyme, it is difficult to determine precisely how their interactions influence dental epithelial differentiation in vivo. Therefore, we analyzed β1 integrin conditional knockout mice (Intβ1lox-/lox-/K14-Cre and found that they exhibited partial enamel hypoplasia, and delayed eruption of molars and differentiation of ameloblasts, but not of odontoblasts. Furthermore, a cyst-like structure was observed during late ameloblast maturation. Dental epithelial cells from knockout mice did not bind to fibronectin, and induction of ameloblastin expression in these cells by neurotrophic factor-4 was inhibited by treatment with RGD peptide or a fibronectin siRNA, suggesting that the epithelial interaction between fibronectin and β1 integrin is important for ameloblast differentiation and enamel formation.

  4. Development of the rudimental tooth primordia as part of mouse odontogenesis

    Czech Academy of Sciences Publication Activity Database

    Peterková, Renata; Peterka, Miroslav; Viriot, L.; Lesot, H.

    La LondelesMaures : organising comittee, 2001. s. 0-51. [Seventh International Conference on Tooth Morphogenesis and Differentiation. 16.06.2001-21.06.2001, La Londe-les-Maures] R&D Projects: GA AV ČR IAA7039901; GA MŠk OC B8.10 Keywords : diastema * molar * incisor Subject RIV: EA - Cell Biology

  5. Transcription Factors Foxi3 and Sox2 in the Regulation of Tooth Development

    OpenAIRE

    Jussila, Maria

    2014-01-01

    Teeth are ectodermal organs, which form from the embryonic epithelium and mesenchyme. Reciprocal interactions between these two tissues, regulated by the conserved signaling pathways, guide tooth morphogenesis. Activity of each signaling pathway is mediated by transcription factors, which activate or repress target genes of the pathway. During morphogenesis, the shape of the dental epithelium undergoes dramatic changes as it proceeds though placode, bud, and cap stages, finally forming the sh...

  6. Arrested diatreme development: Standing Rocks East, Hopi Buttes, Navajo Nation, USA

    Science.gov (United States)

    Lefebvre, Nathalie S.; White, James D. L.; Kjarsgaard, Bruce A.

    2016-01-01

    fluidal, folded-over shapes and ropy surfaces, subordinate thermally altered wall-rock and variegated domains of lapilli tuff. SRE shows a progressive transition from fissure to diatreme, and overall evolution from more explosive to weakly explosive eruption styles recorded at the conduit-crater transition. Diatreme development was initiated by deep-quarrying explosive eruptions along a fissure to form the country rock-rich breccia. Only parts of the fissure remained active as magma feeding the highly explosive eruptions along the fissure localized into discrete point sources forming the matrix-rich lapilli tuff deposits. These superimposed deposits record the passage of multiple debris-jets and subvertical fallback from shallow cratering arising from explosions triggered by magma-water interaction at numerous, discrete sites. However, instead of continuing to build a well-formed diatreme, the system switched to weak spattering with intermittent explosive activity and near-surface dike emplacement into the unconsolidated anisotropic, pyroclastic debris of the crater floor. Dominant spatter from strombolian-style bursts accumulated on the topographically varied, evolving unstable syn-eruptive crater floor, and led to local failure and remobilization. This study demonstrates how the combination of fissure behavior and sensitivity of the shallow plumbing system to local conditions during an eruption can lead to a decrease in eruptive footprint within the diatreme structure, and an overall decrease in explosivity resulting in the arrested development of an immature diatreme.

  7. Tooth patterning and evolution.

    Science.gov (United States)

    Salazar-Ciudad, Isaac

    2012-12-01

    Teeth are a good system for studying development and evolution. Tooth development is largely independent of the rest of the body and teeth can be grown in culture to attain almost normal morphology. Their development is not affected by the patterns of movement or sensorial perception in the embryo. Teeth are hard and easily preserved. Thus, there is plenty of easily accessible information about the patterns of morphological variation occurring between and within species. This review summarises recent work and describes how tooth development can be understood as the coupling between a reaction-diffusion system and differential growth produced by diffusible growth factors: which growth factors are involved, how they affect each other's expression and how they affect the spatial patterns of proliferation that lead to final morphology. There are some aspects of tooth development, however, that do not conform to some common assumptions in many reaction-diffusion models. Those are discussed here since they provide clues about how reaction-diffusion systems may work in actual developmental systems. Mathematical models implementing what we know about tooth development are discussed. PMID:23266218

  8. Biology of tooth replacement in amniotes

    Institute of Scientific and Technical Information of China (English)

    John A Whitlock; Joy M Richman

    2013-01-01

    Tooth replacement is a common trait to most vertebrates, including mammals. Mammals, however, have lost the capacity for continuous tooth renewal seen in most other vertebrates, and typically have only 1–2 generations of teeth. Here, we review the mechanisms of tooth replacement in reptiles and mammals, and discuss in detail the current and historical theories on control of timing and pattern of tooth replacement and development.

  9. Development and microstructure of tooth histotypes in the blue shark, Prionace glauca (Carcharhiniformes: Carcharhinidae) and the great white shark, Carcharodon carcharias (Lamniformes: Lamnidae).

    Science.gov (United States)

    Moyer, Joshua K; Riccio, Mark L; Bemis, William E

    2015-07-01

    Elasmobranchs exhibit two distinct arrangements of mineralized tissues in the teeth that are known as orthodont and osteodont histotypes. Traditionally, it has been said that orthodont teeth maintain a pulp cavity throughout tooth development whereas osteodont teeth are filled with osteodentine and lack a pulp cavity when fully developed. We used light microscopy, scanning electron microscopy, and high-resolution micro-computed tomography to compare the structure and development of elasmobranch teeth representing the two histotypes. As an example of the orthodont histotype, we studied teeth of the blue shark, Prionace glauca (Carcharhiniformes: Carcharhinidae). For the osteodont histotype, we studied teeth of the great white shark, Carcharodon carcharias (Lamniformes: Lamnidae). We document similarities and differences in tooth development and the microstructure of tissues in these two species and review the history of definitions and interpretations of elasmobranch tooth histotypes. We discuss a possible correlation between tooth histotype and tooth replacement and review the history of histotype differentiation in sharks. We find that contrary to a long held misconception, there is no orthodentine in the osteodont teeth of C. carcharias. PMID:25845614

  10. Orthodontic Tooth Movement: A Historic Prospective.

    Science.gov (United States)

    Will, Leslie A

    2016-01-01

    The earliest report on orthodontic tooth movement in the English literature was published in 1911. Oppenheim carried out studies on baboons to determine what histologic changes occurred during tooth movement. Reitan and many others carried out research into the nature of tooth movement. The pressure-tension model of tooth movement developed from these studies, whereby the two sides of the tooth responded to forces as if in isolation. A second theory, proposed by Stuteville in 1938, was the hydraulic theory of tooth movement. In this theory, fluid from the vasculature, lymphatic system and intercellular spaces responds to the forces of tooth movement, damping the force and limiting movement. Bien and Baumrind expanded on this theory with their own studies in the 1960s. It is clear that both the pressure-tension and fluid flow concepts have merit, but considerable work needs to be done to ascertain the details so that tooth movement can be managed and controlled. PMID:26599117

  11. The biology behind the counts: tooth development related to age estimation in beluga (Delphinapterus leucas

    Directory of Open Access Journals (Sweden)

    Barbara E Stewart

    2014-11-01

    Full Text Available The widely accepted method of determining ages of beluga is to count dentine growth layer groups (GLGs in median, longitudinal sections of a tooth. It is essential to understand how these growth layers form and to consider developmental factors that can confound their enumeration to be able to provide meaningful age estimates. Here we provide information on, and illustrate, the developmental biology of beluga teeth as it relates to interpreting GLGs. Key factors are: evaluating the presence and occlusal wear of fetal dentine; interpreting early-formed diagnostic features such as the neonatal line; assessing the last-formed growth layer adjacent to the pulp cavity; identifying the presence of nodes at the dentine-cementum interface to assist in counting GLGs; and recognizing  pulp stones and accessory lines in the dentine which may hinder the age estimate process.

  12. Facioscapulohumeral muscular dystrophy (FSHD) region gene 1 (FRG1) expression and possible function in mouse tooth germ development.

    Science.gov (United States)

    Hasegawa, Kana; Wada, Hiroko; Nagata, Kengo; Fujiwara, Hiroaki; Wada, Naohisa; Someya, Hirotaka; Mikami, Yurie; Sakai, Hidetaka; Kiyoshima, Tamotsu

    2016-08-01

    Abnormal expression of Facioscapulohumeral muscular dystrophy (FSHD) region gene 1 (FRG1) is involved in the pathogenesis of FSHD. FRG1 is also important for the normal muscular and vascular development. Our previous study showed that FRG1 is one of the highly expressed genes in the mandible on embryonic day 10.5 (E10.5) than on E12.0. In this study, we investigated the temporospatial expression pattern of FRG1 mRNA and protein during the development of the mouse lower first molar, and also evaluated the subcellular localization of the FRG1 protein in mouse dental epithelial (mDE6) cells. The FRG1 expression was identified in the dental epithelial and mesenchymal cells at the initiation and bud stages. It was detected in the inner enamel epithelium at the cap and early bell stages. At the late bell and root formation stages, these signals were detected in ameloblasts and odontoblasts during the formation of enamel and dentin matrices, respectively. The FRG1 protein was localized in the cytoplasm in the mouse tooth germ in vivo, while FRG1 was detected predominantly in the nucleus and faintly in the cytoplasm in mDE6 cells in vitro. In mDE6 cells treated with bone morphogenetic protein 4 (BMP4), the protein expression of FRG1 increased in cytoplasm, suggesting that FRG1 may translocate to the cytoplasm. These findings suggest that FRG1 is involved in the morphogenesis of the tooth germ, as well as in the formation of enamel and dentin matrices and that FRG1 may play a role in the odontogenesis in the mouse following BMP4 stimulation. PMID:27234941

  13. Conservation and variation in enamel protein distribution during vertebrate tooth development.

    Science.gov (United States)

    Satchell, Paul G; Anderton, Xochitl; Ryu, Okhee H; Luan, Xianghong; Ortega, Adam J; Opamen, Rene; Berman, Brett J; Witherspoon, David E; Gutmann, James L; Yamane, Akira; Zeichner-David, Margerita; Simmer, James P; Shuler, Charles F; Diekwisch, Thomas G H

    2002-08-15

    Vertebrate enamel formation is a unique synthesis of the function of highly specialized enamel proteins and their effect on the growth and organization of apatite crystals. Among tetrapods, the physical structure of enamel is highly conserved, while there is a greater variety of enameloid tooth coverings in fish. In the present study, we postulated that in enamel microstructures of similar organization, the principle components of the enamel protein matrix would have to be highly conserved. In order to identify the enamel proteins that might be most highly conserved and thus potentially most essential to the process of mammalian enamel formation, we used immunoscreening with enamel protein antibodies as a means to assay for degrees of homology to mammalian enamel proteins. Enamel preparations from mouse, gecko, frog, lungfish, and shark were screened with mammalian enamel protein antibodies, including amelogenin, enamelin, tuftelin, MMP20, and EMSP1. Our results demonstrated that amelogenin was the most highly conserved enamel protein associated with the enamel organ, enamelin featured a distinct presence in shark enameloid but was also present in the enamel organ of other species, while the other enamel proteins, tuftelin, MMP20, and EMSP1, were detected in both in the enamel organ and in other tissues of all species investigated. We thus conclude that the investigated enamel proteins, amelogenin, enamelin, tuftelin, MMP20, and EMSP1, were highly conserved in a variety of vertebrate species. We speculate that there might be a unique correlation between amelogenin-rich tetrapod and lungfish enamel with long and parallel crystals and enamelin-rich basal vertebrate enameloid with diverse patterns of crystal organization. PMID:12210110

  14. Evolution of high tooth replacement rates in sauropod dinosaurs.

    Directory of Open Access Journals (Sweden)

    Michael D D'Emic

    Full Text Available BACKGROUND: Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. METHODOLOGY/PRINCIPAL FINDINGS: We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days. Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. CONCLUSIONS/SIGNIFICANCE: Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size, and derived titanosaurs and

  15. For the development of therapy with ionising radiation in tooth, mouth and jaw medicine. An historical summary

    International Nuclear Information System (INIS)

    Based on the corresponding literature study, the development of therapy with ionising radiation, especially in the areas of tooth, mouth and jaw medicine, is reported from the discovery of X-rays up till the present. First from 1915 on did the X-ray antiphlogistic irradiation with in importance, from 1925 to about 1940 it played a domineering role, after the war was hardly still in use and since 1970 is considered in the stomatological sector obsolete. In comparison, already in 1905 there were individual successes in tumor therapy using X radiation. After many failures and competition with the method of radium therapy in the following years, a new upswing in X-radiation came starting in around 1930 with the introduction of the Chaoul contact therapy. The high point of this development is the introduction of supervolt therapy starting around 1965. It is the result of comprehensive research in the area of radiation physics. As a result of further developed techniques there were soon combined and competing procedures available, whose results, however, have not been adequately compared and documented. From 1970 on electronic data processing has primarily taken over individual irradiation planning (cobalt 60 and electron irradiation), predictions about clinically relevant therapy successes are not present at this time. (TRV)

  16. Metoclopramide-induced cardiac arrest

    Directory of Open Access Journals (Sweden)

    Martha M. Rumore

    2011-11-01

    Full Text Available The authors report a case of cardiac arrest in a patient receiving intravenous (IV metoclopramide and review the pertinent literature. A 62-year-old morbidly obese female admitted for a gastric sleeve procedure, developed cardiac arrest within one minute of receiving metoclopramide 10 mg via slow intravenous (IV injection. Bradycardia at 4 beats/min immediately appeared, progressing rapidly to asystole. Chest compressions restored vital function. Electrocardiogram (ECG revealed ST depression indicative of myocardial injury. Following intubation, the patient was transferred to the intensive care unit. Various cardiac dysrrhythmias including supraventricular tachycardia (SVT associated with hypertension and atrial fibrillation occurred. Following IV esmolol and metoprolol, the patient reverted to normal sinus rhythm. Repeat ECGs revealed ST depression resolution without pre-admission changes. Metoclopramide is a non-specific dopamine receptor antagonist. Seven cases of cardiac arrest and one of sinus arrest with metoclopramide were found in the literature. The metoclopramide prescribing information does not list precautions or adverse drug reactions (ADRs related to cardiac arrest. The reaction is not dose related but may relate to the IV administration route. Coronary artery disease was the sole risk factor identified. According to Naranjo, the association was possible. Other reports of cardiac arrest, severe bradycardia, and SVT were reviewed. In one case, five separate IV doses of 10 mg metoclopramide were immediately followed by asystole repeatedly. The mechanism(s underlying metoclopramide’s cardiac arrest-inducing effects is unknown. Structural similarities to procainamide may play a role. In view of eight previous cases of cardiac arrest from metoclopramide having been reported, further elucidation of this ADR and patient monitoring is needed. Our report should alert clinicians to monitor patients and remain diligent in surveillance and

  17. "Drink beer regularly - it's good for you (and us)": selling Tooth's Beer in a depressed market.

    Science.gov (United States)

    Crawford, Robert

    2007-01-01

    This study examines the unique publicity activities devised by the Tooth's brewery in Sydney during the Great Depression and the 1930s. Unlike many advertisers, the brewery did not turn its back on advertising or marketing. Recognising the importance of publicity, the brewery developed innovative advertising and marketing initiatives in an attempt to arrest its declining sales. Such strategies included the development of co-operative advertising campaigns, the creation of advertisements directly targeting female consumers, and the renovation of pubs owned by the brewery. However, the significance of these initiatives extends beyond the immediate economic concerns. They were also celebration of modernity. By locating Tooth's advertising, marketing, and public relations activities within the broader social, cultural, and political context, this study provides a revealing insight into the way in which such campaigns simultaneously informed and reflected the Australian experience of modernity during the 1930s. PMID:20069745

  18. Terpenes Arrest Parasite Development and Inhibit Biosynthesis of Isoprenoids in Plasmodium falciparum

    OpenAIRE

    Rodrigues Goulart, Herbert; Kimura, Emília A.; Peres, Valnice J.; Couto, Alicia S.; Aquino Duarte, Fulgencio A.; Katzin, Alejandro M.

    2004-01-01

    Development of new drugs is one of the strategies for malaria control. The biosynthesis of several isoprenoids in Plasmodium falciparum was recently described. Interestingly, some intermediates and final products biosynthesized by this pathway in mammals differ from those biosynthesized in P. falciparum. These facts prompted us to evaluate various terpenes, molecules with a similar chemical structure to the intermediates of the isoprenoids pathway, as potential antimalarial drugs. Different t...

  19. Arrested Development: High-Resolution Imaging of Foveal Morphology in Albinism

    OpenAIRE

    McAllister, John T.; Dubis, Adam M.; Tait, Diane M.; Ostler, Shawn; Rha, Jungtae; Stepien, Kimberly E; Summers, C. Gail; Carroll, Joseph

    2010-01-01

    Albinism, an inherited disorder of melanin biosynthesis, disrupts normal retinal development, with foveal hypoplasia as one of the more commonly associated ocular phenotypes. However the cellular integrity of the fovea in albinism is not well understood – there likely exist important anatomical differences that underlie phenotypic variability within the disease and that also may affect responsiveness to therapeutic intervention. Here, using spectral domain optical coherence tomography (SD-OCT...

  20. The Slice Culture Method for Following Development of Tooth Germs In Explant Culture

    OpenAIRE

    Alfaqeeh, Sarah A; Tucker, Abigail S.

    2013-01-01

    Explant culture allows manipulation of developing organs at specific time points and is therefore an important method for the developmental biologist. For many organs it is difficult to access developing tissue to allow monitoring during ex vivo culture. The slice culture method allows access to tissue so that morphogenetic movements can be followed and specific cell populations can be targeted for manipulation or lineage tracing.

  1. Embryonic Lethality Due to Arrested Cardiac Development in Psip1/Hdgfrp2 Double-Deficient Mice.

    Directory of Open Access Journals (Sweden)

    Hao Wang

    Full Text Available Hepatoma-derived growth factor (HDGF related protein 2 (HRP2 and lens epithelium-derived growth factor (LEDGF/p75 are closely related members of the HRP2 protein family. LEDGF/p75 has been implicated in numerous human pathologies including cancer, autoimmunity, and infectious disease. Knockout of the Psip1 gene, which encodes for LEDGF/p75 and the shorter LEDGF/p52 isoform, was previously shown to cause perinatal lethality in mice. The function of HRP2 was by contrast largely unknown. To learn about the role of HRP2 in development, we knocked out the Hdgfrp2 gene, which encodes for HRP2, in both normal and Psip1 knockout mice. Hdgfrp2 knockout mice developed normally and were fertile. By contrast, the double deficient mice died at approximate embryonic day (E 13.5. Histological examination revealed ventricular septal defect (VSD associated with E14.5 double knockout embryos. To investigate the underlying molecular mechanism(s, RNA recovered from ventricular tissue was subjected to RNA-sequencing on the Illumina platform. Bioinformatic analysis revealed several genes and biological pathways that were significantly deregulated by the Psip1 knockout and/or Psip1/Hdgfrp2 double knockout. Among the dozen genes known to encode for LEDGF/p75 binding factors, only the expression of Nova1, which encodes an RNA splicing factor, was significantly deregulated by the knockouts. However the expression of other RNA splicing factors, including the LEDGF/p52-interacting protein ASF/SF2, was not significantly altered, indicating that deregulation of global RNA splicing was not a driving factor in the pathology of the VSD. Tumor growth factor (Tgf β-signaling, which plays a key role in cardiac morphogenesis during development, was the only pathway significantly deregulated by the double knockout as compared to control and Psip1 knockout samples. We accordingly speculate that deregulated Tgf-β signaling was a contributing factor to the VSD and prenatal lethality

  2. The effect of 1,25-dihydroxyvitamin D3 on MSX2 gene expression during tooth and alveolar bone development

    Directory of Open Access Journals (Sweden)

    Intan Ruspita

    2015-03-01

    Full Text Available Background: 1,25-dihydroxyvitamin D3 has been proven to be able to control the formation and biomineralization of tissue through a regulatory gene. A previous research even showed that a cell responsible for the formation of the enamel (ameloblasts, dentin (odontoblasts and bone (osteoblasts, osteoclasts was the target of  1,25-dihydroxivitamin D3. Purpose: This research was aimed to determine the role of 1,25- dihydroxyvitamin D3 in vivo in the development of teeth and alveolar bone tissue by analyzing MSX2 gene expression as a gene marker responsible for the growth and development of enamel, dentin, tooth root and alveolar bone. Methods: Samples used for RT-PCR analysis were total RNA of insisivus teeth and alveolar bone derived from mice. RT-PCR analysis was conducted by using primer-specific gene, MSX2. Primer gene, GAPDH, was also used as an internal control. Five hundred nanograms of total RNA were used as a template for PCR. Semi quantitative results of PCR were quantified by using ImageJ software. Results: RT-PCR analysis showed that the expression level of MSX2 was enhanced in the samples of teeth and alveolar bone treated with 1,25 dihydroxyvitamin D3. The increasing of MSX2 expression significantly occurred in alveolar bone samples. Conclusion: It can be concluded that 1,25 dihydroxyvitamin D3 could enhance MSX2 expression as a marker of the development of teeth and alveolar bone tissue. Therefore, 1,25-D3 dihydroxyvitamin is expected to be used as an agent to help the regeneration of teeth and bone tissue.

  3. Tooth-bone morphogenesis during postnatal stages of mouse first molar development

    Czech Academy of Sciences Publication Activity Database

    Lungová, V.; Radlanski, R.J.; Tucker, A. S.; Renz, H.; Míšek, Ivan; Matalová, Eva

    2011-01-01

    Roč. 218, č. 6 (2011), s. 699-716. ISSN 0021-8782 R&D Projects: GA ČR GC524/08/J032; GA MZd(CZ) NT11420 Institutional research plan: CEZ:AV0Z50450515 Keywords : apoptosis * dentition * development Subject RIV: EA - Cell Biology Impact factor: 2.370, year: 2011

  4. A study of the cell adhesions molecules, E-Cadherin and C-CAM, and the intermediate filaments, nestin, in craniofacial and tooth development

    OpenAIRE

    Terling, Catharina

    1998-01-01

    A STUDY OF THE CELL ADHESION MOLECULES, E-CADHERIN AND C-CAM AND THE INTERMEDIATE FILAMENT NESTIN IN CRANIOFACIAL AND TOOTH DEVELOPMENT. Catharina Terling The Department of Basic Oral Sciences, The Center of Oral Biology, Novum Research Park and The Department of Cell and Molecular Biology, Medical Nobel Institute, Karolinska Institutet, Sweden Cell adhesion molecules (CAMs) are involved in cell migration, morphogenesis, and cell differentiation within the embryo, and ...

  5. The Effects of Irradiation and Calcium-deficient Diet on the Expression of Bone Morphogenetic Protein-2/4 during Early Tooth Development

    International Nuclear Information System (INIS)

    To investigate the expression of bone morphogenetic protein (BMP)-2/4 during early tooth development after irradiation and calcium-deficient diet. The pregnant three-week-old Sprague-Dawley rats were used for the study. The control group was non-irradiation/normal diet group (Group 1), and the experimental groups were irradiation/normal diet group (Group 2) and irradiation/calcium-diet group (Group 3). The abdomen of the rats at the 9th day of pregnancy were irradiated with single dose of 350 cGy. The rat pups were sacrificed at embryonic 18 days, 3 days and 14 days after delivery and the maxillae tooth germs were taken. The tissue sections of specimen were stained immunohistochemically with anti-BMP-2/4 antibody. At embryo-18 days, immunoreacivity for BMP-2/4 of the Group 1 was modetate in stratum intermedium of dental organ and weak in dental papilla and dental follicle, but that of Group 2 was weak in cell layer of dental organ, and no immunoreacivity was shown in dental papilla and dental follice of Group 2 and in all tissue components of the Group 3. At postnatal-3 days, immunoreacivity for BMP-2/4 of the Group 1 was strong in cell layer of dental organ, odontoblasts and developing alveolar bone, but that of Group of 2 and Group 3 was weak in odontoblasts and developing alveolar bone. At postnatal-14 days, immunoreacivity for BMP-2/4 of the Group 1 was strong in newly formed cementum, alveolar bone and odontoblasts, but that of Group 2 was weaker than that of Group 1. In the Group 3, tooth forming cell layer showed weak immunoreactivity, but other cell layers showed no immunoreactivity. The expression of bone morphogenetic protein (BMP)-2/4 during early tooth development was disturbed after irradiation and calcium-deficient diet.

  6. The Effects of Irradiation and Calcium-deficient Diet on the Expression of Bone Morphogenetic Protein-2/4 during Early Tooth Development

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dai Hee; Hwang, Eui Hwan; Lee, Sang Rae [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Kyunghee University, Seoul (Korea, Republic of)

    2000-09-15

    To investigate the expression of bone morphogenetic protein (BMP)-2/4 during early tooth development after irradiation and calcium-deficient diet. The pregnant three-week-old Sprague-Dawley rats were used for the study. The control group was non-irradiation/normal diet group (Group 1), and the experimental groups were irradiation/normal diet group (Group 2) and irradiation/calcium-diet group (Group 3). The abdomen of the rats at the 9th day of pregnancy were irradiated with single dose of 350 cGy. The rat pups were sacrificed at embryonic 18 days, 3 days and 14 days after delivery and the maxillae tooth germs were taken. The tissue sections of specimen were stained immunohistochemically with anti-BMP-2/4 antibody. At embryo-18 days, immunoreacivity for BMP-2/4 of the Group 1 was modetate in stratum intermedium of dental organ and weak in dental papilla and dental follicle, but that of Group 2 was weak in cell layer of dental organ, and no immunoreacivity was shown in dental papilla and dental follice of Group 2 and in all tissue components of the Group 3. At postnatal-3 days, immunoreacivity for BMP-2/4 of the Group 1 was strong in cell layer of dental organ, odontoblasts and developing alveolar bone, but that of Group of 2 and Group 3 was weak in odontoblasts and developing alveolar bone. At postnatal-14 days, immunoreacivity for BMP-2/4 of the Group 1 was strong in newly formed cementum, alveolar bone and odontoblasts, but that of Group 2 was weaker than that of Group 1. In the Group 3, tooth forming cell layer showed weak immunoreactivity, but other cell layers showed no immunoreactivity. The expression of bone morphogenetic protein (BMP)-2/4 during early tooth development was disturbed after irradiation and calcium-deficient diet.

  7. Deterrence and arrest ratios.

    Science.gov (United States)

    Carmichael, Stephanie E; Piquero, Alex R

    2006-02-01

    In the limited research on the origins of sanction threat perceptions, researchers have focused on either the effects of actively engaging in crime or the effects of formal sanctioning but rarely on both (i.e., the arrest ratio or the number of arrests relative to the number of crimes committed). This article extends this line of research by using a sample of Colorado inmates and measures arrest ratios and sanction perceptions for eight different crime types. Analyses reveal that the offenders report both significant experiential and arrest ratio effects. Theoretical and policy implications, limitations, and directions for future research are outlined. PMID:16397123

  8. Broken or knocked out tooth

    Science.gov (United States)

    Teeth - broken; Tooth - knocked out ... dentist right away. If your tooth is badly broken, your nerve endings may be exposed. You will ... emergency visit for a simple chip or a broken tooth that is not causing you discomfort. You ...

  9. In utero and lactational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) affects tooth development in rhesus monkeys

    Energy Technology Data Exchange (ETDEWEB)

    Yasuda, Iku; Kazuhiro, Tsuga; Yasumasa, Akagawa [Hiroshima Univ. (Japan); Mineo, Yasuda; Hiroshi, Sumida [Hiroshima International Univ. (Japan); Akihiro, Arima; Toshio, Ihara [Shin Nippon Biomedical Laboratories, Ltd., Kagoshima (Japan); Shunichiro, Kubota [Tokyo Univ. (Japan); Kazuo, Asaoka [Kyoto Univ., Inuyama (Japan). Primate Research Institute; Takumi, Takasuga [Shimadzu Techno-Research Inc., Kyoto (Japan)

    2004-09-15

    The current tolerable daily intake (TDI) of dioxin and dioxin related compounds has been set at 4 pg TEQ/kg/day in Japan. This value was calculated from the lowest-observed-adverse-effect level (LOAEL) in experimental animals, mostly rodents. Gray et al. reported that a single oral dose of 200 ng/kg of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to pregnant rats on day 15 of gestation resulted in abnormalities of reproductive organs in the offspring. The maternal body burden at this dose was measured to be 86 ng/kg. To attain this body burden level, human daily intake was calculated to be 43.6 pg/kg/day. An uncertainty factor of 10 was applied to this value, and the human TDI was established. However, due to great differences in the biological half life of TCDD between human and rodents, the validity of this calculation is questioned. To obtain more reliable LOAEL in the second generation, we initiated a long-term study in rhesus monkeys in 1999. In rodents, teeth are known to be targets of developmental toxicity of dioxin. In utero and lactational TCDD exposure affects rat incisor and molar development. In humans also tooth abnormalities were reported among populations exposed to dioxins. In our monkey experiment, some young were stillborn or died neonatally. These animals provided us with a unique opportunity to study tooth development in primate young exposed to TCDD in utero and lactationally. By macroscopic observation we found some tooth abnormalities among died young exposed to TCDD5. This prompted us to examine surviving young by radiography. This is an interim report of our findings in these young.

  10. Genetics And Tooth Anomalies - An Update

    OpenAIRE

    Aswathy Brahmanandan; Ahmed Hasan Farooqi T; Deepa.M.S; Aswathy Raj R

    2013-01-01

    Tooth development like the development of all epithelial appendages is regulated by inductive tissue interactions between epithelium and mesenchyme. Numerous genes interact, either act in conjunction or antagonize each other in odontogenesis. A number of different mesenchymal molecules and their receptors act as mediators in epithelial mesenchymal interactions. Several genes linked with early tooth positioning and developments belong to signaling pathways and have morphogenesis regulatory f...

  11. Computer simulation of gear tooth manufacturing processes

    Science.gov (United States)

    Mavriplis, Dimitri; Huston, Ronald L.

    1990-01-01

    The use of computer graphics to simulate gear tooth manufacturing procedures is discussed. An analytical basis for the simulation is established for spur gears. The simulation itself, however, is developed not only for spur gears, but for straight bevel gears as well. The applications of the developed procedure extend from the development of finite element models of heretofore intractable geometrical forms, to exploring the fabrication of nonstandard tooth forms.

  12. An experimental study on the effect of betatron electron rays irradiation on the developing permanent tooth and its surrounding tissues of the young dog

    International Nuclear Information System (INIS)

    A dose of 4 MeV, Betatron electronic rays, 600 rad and 1200 rad were applied to the 3rd primary molar and the 4th permanent premolar germ, respectively in the right mandibles of 58 young (3 mo.) dogs. In both irradiated groups disturbance of enamel formation was observed on and after the 21st day after irradiation. After the 21st day pulp cells around the cervical end of the dentin were arranged radially, meeting at right angles with collagenous fibers developing within immature pulp tissue. In the 1200 rad group, destruction of Hertwig's epithelial sheath was observed on the 14th day, and on the 30th day the sheath disappeared. About that time, osteoblast-like cells different from odontoblast appeared, and osteodentin began to form. In the 600 rad group, little trouble in dentin and pulp tissues was observed, and only hypoplasia of the enamel was noticed. These observation suggested that the radiosensitivity of the ameloblasts derived from the ectoderm was higher than the other. In the 1200 rad dose group, enamel hypoplasia, osteodentin formation, reticular atrophy of pulp and shortening of tooth root were found. These findings were not so different from results of predecessors in experiments with over 1000 R. In both the 600 and 1200 rad dose groups growth of the permanent tooth showed remarkably delay and severe crowding within the mendible. In the primary tooth, there was slight pulp congestion and a decreased number of pulp cells. In the 600 rad dose group, the mandible was unaffected, but in the 1200 rad group there was congestion of bone marrow, fibrous degeneration of bone tissue and so on. (Evans, J.)

  13. Computer aided design and analysis of gear tooth geometry

    Science.gov (United States)

    Chang, S. H.; Huston, R. L.

    1987-01-01

    A simulation method for gear hobbing and shaping of straight and spiral bevel gears is presented. The method is based upon an enveloping theory for gear tooth profile generation. The procedure is applicable in the computer aided design of standard and nonstandard tooth forms. An inverse procedure for finding a conjugate gear tooth profile is presented for arbitrary cutter geometry. The kinematic relations for the tooth surfaces of straight and spiral bevel gears are proposed. The tooth surface equations for these gears are formulated in a manner suitable for their automated numerical development and solution.

  14. Myocardial stunning after resuscitation from cardiac arrest following spinal anaesthesia

    OpenAIRE

    Pranjali Madhav Kurhekar; VSG Yachendra; Simi P Babu; Raghavelu Govindasamy

    2014-01-01

    Cardiac arrest associated with spinal anaesthesia has been well researched. Myocardial stunning after successful resuscitation from cardiac arrest is seen in up to 2/3 rd of in-hospital cardiac arrests. Myocardial stunning after resuscitation from cardiac arrest associated with spinal anaesthesia has probably not been reported earlier. Our case, an ASA physical status I lady, posted for tubal reanastomosis surgery developed bradycardia followed by asystole, approximately 5 minutes after givin...

  15. Genetics And Tooth Anomalies - An Update

    Directory of Open Access Journals (Sweden)

    Aswathy Brahmanandan

    2013-01-01

    Full Text Available Tooth development like the development of all epithelial appendages is regulated by inductive tissue interactions between epithelium and mesenchyme. Numerous genes interact, either act in conjunction or antagonize each other in odontogenesis. A number of different mesenchymal molecules and their receptors act as mediators in epithelial mesenchymal interactions. Several genes linked with early tooth positioning and developments belong to signaling pathways and have morphogenesis regulatory functions in morphogenesis of other organs. Their mutations often show pleiotropic effects beyond dental morphogenesis. In contrast, certain genes involved in enamel and dentin structures are highly specific for tooth. Mutations in these genes have been identified as causes of Amelogenesis Imperfecta (AI, Dentinogenesis Imperfecta (DI, Dentin Dysplasia (DD and anomalies in tooth number. This article focuses on genetic basis of inherited non-syndromic teeth disorders.

  16. Advancing automation of power distribution facilities and the cost reduction measures. Development of a polymer vessel-type arrester; Susumu haiden setsubi no jidoka, cost teigen taisaku. Polymer yokigata hiraiki no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Izumi, K. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1998-07-01

    An arrester has a function for keeping the insulation of lines by discharging the surge over-voltage of thunderbolt into the earth. Zinc oxide type arresters with zinc oxide device as a characteristic element are mainly used. A 6,000 V-class arrester for distribution has been developed using an umbrella type polymer insulation vessel instead of a ceramic vessel usually used as a vessel for containing the zinc oxide device. This paper describes the structure and performance of this arrester. For this arrester, zinc oxide devices are stacked in the FRP cylinder and fixed by tightening them using a spring, which is covered by the umbrella type polymer insulator made of silicone rubber. When comparing with the ceramic vessel type arrester, its weight is a half, and its height is about 60%. Thus, light weight and down-sizing are realized. Basic performances such as working start voltage, limit voltage and thunderbolt surge working responsibility were verified. Exploration-proof performance, contamination-proof insulation performance, gas tightness performance and long-term performance were successfully verified, as well. 2 figs.

  17. Cardiac arrest: resuscitation and reperfusion.

    Science.gov (United States)

    Patil, Kaustubha D; Halperin, Henry R; Becker, Lance B

    2015-06-01

    The modern treatment of cardiac arrest is an increasingly complex medical procedure with a rapidly changing array of therapeutic approaches designed to restore life to victims of sudden death. The 2 primary goals of providing artificial circulation and defibrillation to halt ventricular fibrillation remain of paramount importance for saving lives. They have undergone significant improvements in technology and dissemination into the community subsequent to their establishment 60 years ago. The evolution of artificial circulation includes efforts to optimize manual cardiopulmonary resuscitation, external mechanical cardiopulmonary resuscitation devices designed to augment circulation, and may soon advance further into the rapid deployment of specially designed internal emergency cardiopulmonary bypass devices. The development of defibrillation technologies has progressed from bulky internal defibrillators paddles applied directly to the heart, to manually controlled external defibrillators, to automatic external defibrillators that can now be obtained over-the-counter for widespread use in the community or home. But the modern treatment of cardiac arrest now involves more than merely providing circulation and defibrillation. As suggested by a 3-phase model of treatment, newer approaches targeting patients who have had a more prolonged cardiac arrest include treatment of the metabolic phase of cardiac arrest with therapeutic hypothermia, agents to treat or prevent reperfusion injury, new strategies specifically focused on pulseless electric activity, which is the presenting rhythm in at least one third of cardiac arrests, and aggressive post resuscitation care. There are discoveries at the cellular and molecular level about ischemia and reperfusion pathobiology that may be translated into future new therapies. On the near horizon is the combination of advanced cardiopulmonary bypass plus a cocktail of multiple agents targeted at restoration of normal metabolism and

  18. Dielectric response of the human tooth dentine

    Energy Technology Data Exchange (ETDEWEB)

    Leskovec, J. [Dental Clinic, Faculty of Medicine, University of Ljubljana, Hrvatski trg 6, 1104 Ljubljana (Slovenia); Filipic, C. [Jozef Stefan Institute, P.O. Box 3000, 1001 Ljubljana (Slovenia); Levstik, A. [Jozef Stefan Institute, P.O. Box 3000, 1001 Ljubljana (Slovenia)]. E-mail: adrijan.levstik@ijs.si

    2005-07-15

    Dielectric properties of tooth dentine can be well described by the model which was developed for the dielectric response to hydrating porous cement paste. It is shown that the normalized dielectric constant and the normalized specific conductivity are proportional to the model parameters -bar {sub v0} and {sigma}{sub v}, indicating the deposition of AgCl in the dentine tubules during the duration of the precipitation. The fractal dimension of the tooth dentine was determined by dielectric spectroscopy.

  19. Dielectric response of the human tooth dentine

    International Nuclear Information System (INIS)

    Dielectric properties of tooth dentine can be well described by the model which was developed for the dielectric response to hydrating porous cement paste. It is shown that the normalized dielectric constant and the normalized specific conductivity are proportional to the model parameters -bar v0 and σv, indicating the deposition of AgCl in the dentine tubules during the duration of the precipitation. The fractal dimension of the tooth dentine was determined by dielectric spectroscopy

  20. Dielectric response of the human tooth dentine

    Science.gov (United States)

    Leskovec, J.; Filipič, C.; Levstik, A.

    2005-07-01

    Dielectric properties of tooth dentine can be well described by the model which was developed for the dielectric response to hydrating porous cement paste. It is shown that the normalized dielectric constant and the normalized specific conductivity are proportional to the model parameters ɛ and σv, indicating the deposition of AgCl in the dentine tubules during the duration of the precipitation. The fractal dimension of the tooth dentine was determined by dielectric spectroscopy.

  1. Overview of Tooth Disorders

    Science.gov (United States)

    ... bands and wires or appliances Cap Crown Cavities Caries Cleaning Prophylaxis Eye teeth Canines or cuspids Filling ... Abnormal tooth enamel may be due to a diet containing insufficient vitamin D. Abnormal enamel may also ...

  2. Sudden Cardiac Arrest

    Science.gov (United States)

    ... scan, or MUGA, which shows how well your heart is pumping blood. Magnetic resonance imaging (MRI) which gives doctors detailed pictures of your heart. How is SCA treated? Sudden cardiac arrest should ...

  3. Cardiac arrest in children

    Directory of Open Access Journals (Sweden)

    Tress Erika

    2010-01-01

    Full Text Available Major advances in the field of pediatric cardiac arrest (CA were made during the last decade, starting with the publication of pediatric Utstein guidelines, the 2005 recommendations by the International Liaison Committee on Resuscitation, and culminating in multicenter collaborations. The epidemiology and pathophysiology of in-hospital and out-of-hospital CA are now well described. Four phases of CA are described and the term "post-cardiac arrest syndrome" has been proposed, along with treatment goals for each of its four phases: immediate post-arrest, early post-arrest, intermediate and recovery phase. Hypothermia is recommended to be considered as a therapy for post-CA syndrome in comatose patients after CA, and large multicenter prospective studies are underway. We reviewed landmark articles related to pediatric CA published during the last decade. We present the current knowledge of epidemiology, pathophysiology and treatment of CA relevant to pre-hospital and acute care health practitioners.

  4. Cardiac arrest in children.

    Science.gov (United States)

    Tress, Erika E; Kochanek, Patrick M; Saladino, Richard A; Manole, Mioara D

    2010-07-01

    Major advances in the field of pediatric cardiac arrest (CA) were made during the last decade, starting with the publication of pediatric Utstein guidelines, the 2005 recommendations by the International Liaison Committee on Resuscitation, and culminating in multicenter collaborations. The epidemiology and pathophysiology of in-hospital and out-of-hospital CA are now well described. Four phases of CA are described and the term "post-cardiac arrest syndrome" has been proposed, along with treatment goals for each of its four phases: immediate post-arrest, early post-arrest, intermediate and recovery phase. Hypothermia is recommended to be considered as a therapy for post-CA syndrome in comatose patients after CA, and large multicenter prospective studies are underway. We reviewed landmark articles related to pediatric CA published during the last decade. We present the current knowledge of epidemiology, pathophysiology and treatment of CA relevant to pre-hospital and acute care health practitioners. PMID:20930971

  5. Sudden Cardiac Arrest

    Science.gov (United States)

    ... Heart Risk Factors & Prevention Heart Diseases & Disorders Atrial Fibrillation (AFib) Sudden Cardiac Arrest (SCA) SCA: Who's At Risk? Prevention of SCA What Causes SCA? SCA Awareness Atrial Flutter Heart Block Heart Failure Sick Sinus Syndrome Substances & Heart Rhythm Disorders Symptoms & ...

  6. Sudden Cardiac Arrest

    Science.gov (United States)

    ... often are found in public places, such as shopping malls, golf courses, businesses, airports, airplanes, casinos, ... arrest In a study published online today in the New England Journal of Medicine , ...

  7. Cardiac arrest - cardiopulmonary resuscitation

    Institute of Scientific and Technical Information of China (English)

    Basri Lenjani; Besnik Elshani; Nehat Baftiu; Kelmend Pallaska; Kadir Hyseni; Njazi Gashi; Nexhbedin Karemani; Ilaz Bunjaku; Taxhidin Zaimi; Arianit Jakupi

    2014-01-01

    Objective:To investigate application of cardiopulmonary resuscitation(CPR) measures within the golden minutes inEurope.Methods:The material was taken from theUniversityClinical Center ofKosovo -EmergencyCentre inPristina, during the two(2) year period(2010-2011).The collected date belong to the patients with cardiac arrest have been recorded in the patients' log book protocol at the emergency clinic.Results:During the2010 to2011 in the emergency center of theCUCK inPristina have been treated a total of269 patients with cardiac arrest, of whom159 or59.1% have been treated in2010, and110 patients or40.9% in2011.Of the269 patients treated in the emergency centre,93 or34.6% have exited lethally in the emergency centre, and176 or 65.4% have been transferred to other clinics.In the total number of patients with cardiac arrest, males have dominated with186 cases, or69.1%.The average age of patients included in the survey was56.7 year oldSD±16.0 years.Of the269 patients with cardiac arrest, defibrillation has been applied for93 or34.6% of patients.In the outpatient settings defibrillation has been applied for3 or3.2% of patients.Patients were defibrillated with application of one to four shocks. Of27 cases with who have survived cardiac arrest, none of them have suffered cardiac arrest at home,3 or11.1% of them have suffered cardiac arrest on the street, and24 or88.9% of them have suffered cardiac arrest in the hospital.5 out of27 patients survived have ended with neurological impairment.Cardiac arrest cases were present during all days of the week, but frequently most reported cases have been onMonday with32.0% of cases, and onFriday with24.5% of cases. Conclusions:All survivors from cardiac arrest have received appropriate medical assistance within10 min from attack, which implies that if cardiac arrest occurs near an institution health care(with an opportunity to provide the emergent health care) the rate of survival is higher.

  8. Osteological associations with unique tooth development in manatees (Trichechidae, Sirenia): a detailed look at modern Trichechus and a review of the fossil record.

    Science.gov (United States)

    Beatty, Brian Lee; Vitkovski, Taisia; Lambert, Olivier; Macrini, Thomas E

    2012-09-01

    Modern manatees have a unique type of tooth development, continually forming identical new molars in the posterior end of each quadrant of their mouths, and then progressively moving teeth anteriorly, only to reabsorb roots and spit out worn crowns. This process is not only developmentally complex, but requires space in the oral cavity that imposes its own limitations on other uses of that space. To gain a clearer understanding of the anatomical constraints on the evolution of this unique developmental process, we identified the specialized craniodental features in modern Trichechus that permit this specialization using visual observation and CT. Furthermore, to better understand the evolution of these traits, we review the fossil record of trichechids for these traits, including CT analysis of the skull of Miosiren kocki, a possible early member of the family from the Early Miocene of Belgium. PMID:22777871

  9. Functional constraints on tooth morphology in carnivorous mammals

    OpenAIRE

    Smits Peter D; Evans Alistair R

    2012-01-01

    Abstract Background The range of potential morphologies resulting from evolution is limited by complex interacting processes, ranging from development to function. Quantifying these interactions is important for understanding adaptation and convergent evolution. Using three-dimensional reconstructions of carnivoran and dasyuromorph tooth rows, we compared statistical models of the relationship between tooth row shape and the opposing tooth row, a static feature, as well as measures of mandibu...

  10. Immediate total tooth replacement.

    Science.gov (United States)

    Garber, D A; Salama, M A; Salama, H

    2001-03-01

    Successful implant placement at the time of extraction has been documented. Implant placement at the time of extraction was initially performed as a two-stage procedure often with barrier membranes and sophisticated second-stage surgical uncoverings. The authors describe the next generation of this technique, including atraumatic tooth removal with simultaneous root form, implant placement, and temporization at one appointment. This technique of "Immediate Total Tooth Replacement" allows for the maintenance of the bony housing and soft-tissue form that existed before extraction, while at the same time establishing a root form anchor in the bone for an esthetic restoration. PMID:11913258

  11. Computer-aided design of bevel gear tooth surfaces

    Science.gov (United States)

    Shuo, Hung Chang; Huston, Ronald L.; Coy, John J.

    1989-01-01

    This paper presents a computer-aided design procedure for generating bevel gears. The development is based on examining a perfectly plastic, cone-shaped gear blank rolling over a cutting tooth on a plane crown rack. The resulting impression on the plastic gear blank is the envelope of the cutting tooth. This impression and envelope thus form a conjugate tooth surface. Equations are presented for the locus of points on the tooth surface. The same procedures are then extended to simulate the generation of a spiral bevel gear. The corresponding governing equations are presented.

  12. Computer aided design of bevel gear tooth surfaces

    Science.gov (United States)

    Chang, S. H.; Huston, R. L.; Coy, J. J.

    1989-01-01

    This paper presents a computer-aided design procedure for generating bevel gears. The development is based on examining a perfectly plastic, cone-shaped gear blank rolling over a cutting tooth on a plane crown rack. The resulting impression on the plastic gear blank is the envelope of the cutting tooth. This impression and envelope thus form a conjugate tooth surface. Equations are presented for the locus of points on the tooth surface. The same procedures are then extended to simulate the generation of a spiral bevel gear. The corresponding governing equations are presented.

  13. Msx1 Mutations: How Do They Cause Tooth Agenesis?

    OpenAIRE

    Wang, Y.; Kong, H; Mues, G.; D’Souza, R.

    2011-01-01

    Mutations in the transcription factors PAX9 and MSX1 cause selective tooth agenesis in humans. In tooth bud mesenchyme of mice, both proteins are required for the expression of Bmp4, which is the key signaling factor for progression to the next step of tooth development. We have previously shown that Pax9 can transactivate a 2.4-kb Bmp4 promoter construct, and that most tooth-agenesis-causing PAX9 mutations impair DNA binding and Bmp4 promoter activation. We also found that Msx1 by itself rep...

  14. ROLE OF BACTERIA IN THE TOOTH ABSCESS: A MINI REVIEW

    OpenAIRE

    Biswajit Batabyal; Gautam kr. Kundu

    2013-01-01

    A tooth abscess or root abscess is pus enclosed in the tissues of the jaw bone at the apex of an infected tooth's root(s). Usually the abscess originates from a bacterial infection that has accumulated in the soft, often dead, pulp of the tooth. This can be caused by untreated tooth decay, cracked teeth or extensive periodontal disease. A failed root canal treatment may also create a similar abscess. Recently developed molecular methods have made it possible to characterise mixed micro flora ...

  15. Tooth-shaped plasmonic waveguide filters with nanometeric sizes

    CERN Document Server

    Lin, Xianshi; 10.1364/OL.33.002874

    2009-01-01

    A novel nanometeric plasmonic filter in a tooth-shaped Metal-Insulator-Metal waveguide is proposed and demonstrated numerically. An analytic model based on the scattering matrix method is given. The result reveals that the single tooth-shaped filter has a wavelength filtering characteristic and an ultra-compact size in the length of a few hundred nanometers, compared to grating-like SPPs filters. Both analytic and simulation results show that the wavelength of the trough of the transmission has linear and nonlinear relationships with the tooth depth and the tooth width, respectively. The waveguide filter could be utilized to develop ultra-compact photonic filters for high integration.

  16. Regenerative Applications Using Tooth Derived Stem Cells in Other Than Tooth Regeneration: A Literature Review

    OpenAIRE

    Yun-Jong Park; Seunghee Cha; Young-Seok Park

    2016-01-01

    Tooth derived stem cells or dental stem cells are categorized according to the location from which they are isolated and represent a promising source of cells for regenerative medicine. Originally, as one kind of mesenchymal stem cells, they are considered an alternative of bone marrow stromal cells. They share many commonalties but maintain differences. Considering their original function in development and the homeostasis of tooth structures, many applications of these cells in dentistry ha...

  17. Replacing a Missing Tooth

    Science.gov (United States)

    ... the extra bulk and removable nature of the partial denture and report that it feels unnatural. This type of prosthesis is best as a temporary replacement as described above. The second option in a patient without a bone graft is a fixed bridge. The missing tooth is restored with an ...

  18. Crack-arrest technology

    International Nuclear Information System (INIS)

    Over the last several years, the Heavy Section Steel Technology (HSST) Program has conducted several fracture mechanics experiments on large specimens that produced crack-arrest fracture-toughness values above 220 MPa·√m, which is the limit imposed by the ASME Code and the limit included in the Issues on Pressurized Thermal Shock studies. It is therefore appropriate and timely to investigate the influence that these high crack-arrest data have on the integrity assessment of nuclear Reactor Pressure Vessels (RPVs). A review of the evolution of the Pressurized Thermal Shock (PTS) issue and current methods of analysis provides insight into the motivation for the HSST Program performing the large-specimen fracture mechanics experiments. During the early 1970s, it was recognized that RPVs could be subjected to severe thermal shock as the result of a large-break loss-of-coolant accident (LBLOCA). Analyses performed at that time indicated that thermal shock alone would not result in failure (through-wall cracking) of the vessel. However, a combination of pressure and a less severe thermal shock, the result of some postulated transients, could result in vessel failure. In March 1978, such a transient occurred at the Rancho Seco nuclear power plant. As a result of these events, parametric PTS studies were undertaken. Because of the apparent need for and the existence of high-temperature crack-arrest capability, the NRC HSST Program and others began to investigate the effect of higher crack-arrest values on the probability of failure and to determine if these values actually exist for prototypical RPV materials. This report describes the results of HSST Program large-specimen crack-arrest testing

  19. Tooth Germ-Like Construct Transplantation for Whole-Tooth Regeneration: An In Vivo Study in the Miniature Pig.

    Science.gov (United States)

    Yang, Kai-Chiang; Kitamura, Yutaka; Wu, Chang-Chin; Chang, Hao-Hueng; Ling, Thai-Yen; Kuo, Tzong-Fu

    2016-04-01

    The purpose of this study was to demonstrate the feasibility of whole-tooth regeneration using a tooth germ-like construct. Dental pulp from upper incisors, canines, premolars, and molars were extracted from sexually mature miniature pigs. Pulp tissues were cultured and expanded in vitro to obtain dental pulp stem cells (DPSCs), and cells were differentiated into odontoblasts and osteoblasts. Epithelial cells were isolated from gingival epithelium. The epithelial cells, odontoblasts, and osteoblasts were seeded onto the surface, upper, and lower layers, respectively, of a bioactive scaffold. The lower first and second molar tooth germs were removed bilaterally and the layered cell/scaffold constructs were transplanted to the mandibular alveolar socket of a pig. At 13.5 months postimplantation, seven of eight pigs developed two teeth with crown, root, and pulp structures. Enamel-like tissues, dentin, cementum, odontoblasts, and periodontal tissues were found upon histological inspection. The regenerated tooth expressed dentin matrix protein-1 and osteopontin. All pigs had regenerated molar teeth regardless of the original tooth used to procure the DPSCs. Pigs that had tooth germs removed or who received empty scaffolds did not develop teeth. Although periodontal ligaments were generated, ankylosis was found in some animals. This study revealed that implantation of a tooth germ-like structure generated a complete tooth with a high success rate. The implant location may influence the morphology of the regenerated tooth. PMID:26582651

  20. Myocardial stunning after resuscitation from cardiac arrest following spinal anaesthesia

    Directory of Open Access Journals (Sweden)

    Pranjali Madhav Kurhekar

    2014-01-01

    Full Text Available Cardiac arrest associated with spinal anaesthesia has been well researched. Myocardial stunning after successful resuscitation from cardiac arrest is seen in up to 2/3 rd of in-hospital cardiac arrests. Myocardial stunning after resuscitation from cardiac arrest associated with spinal anaesthesia has probably not been reported earlier. Our case, an ASA physical status I lady, posted for tubal reanastomosis surgery developed bradycardia followed by asystole, approximately 5 minutes after giving subarachnoid block. Return of spontaneous circulation (ROSC was achieved within 2 minutes with cardiopulmonary resuscitation (CPR and defibrillation for pulseless ventricular tachycardia. Patient developed delayed pulmonary oedema, which was probably due to myocardial stunning. In the present case, inadequate preloading could have precipitated bradycardia progressing to cardiac arrest which, after resuscitation led to reversible myocardial dysfunction. We conclude that early vasopressor infusion, titrated fluids and echocardiography should be considered in immediate post cardiac arrest phase following spinal anaesthesia.

  1. Resolution of pathological inflammatory condition before tooth extraction ameliorates ONJ in mice

    OpenAIRE

    Kim, Terresa

    2016-01-01

    Dental-related trauma such as tooth extraction is one of the major risk factors significantly associated with development of medication-related osteonecrosis of the jaw (ONJ). Tooth extraction is usually performed due to underlying pre-existing pathological inflammatory conditions such as periodontitis but it remains largely unknown whether pathological inflammatory conditions exacerbate ONJ development following tooth extraction, or resolving pathological inflammatory condition before tooth ...

  2. Arrested coalescence of viscoelastic droplets: polydisperse doublets.

    Science.gov (United States)

    Dahiya, Prerna; Caggioni, Marco; Spicer, Patrick T

    2016-07-28

    Arrested droplet coalescence produces stable anisotropic shapes and is a key mechanism for microstructure development in foods, petroleum and pharmaceutical formulations. Past work has examined the dynamic elastic arrest of coalescing monodisperse droplet doublets and developed a simple model of doublet strain as a function of physical variables. Although the work describes experimental data well, it is limited to describing same-size droplets. A new model incorporating a generalized description of doublet shape is developed to describe polydisperse doublet formation in more realistic emulsion systems. Polydisperse doublets are shown to arrest at lower strains than monodisperse doublets as a result of the smaller contribution of surface area in a given pair. Larger droplet size ratios have lower relative degrees of strain because coalescence is arrested at an earlier stage than in more monodisperse cases. Experimental observations of polydisperse doublet formation indicate that the model under-predicts arrest strains at low solid levels and small droplet sizes. The discrepancy is hypothesized to be the result of nonlinear elastic deformation at high strains.This article is part of the themed issue 'Soft interfacial materials: from fundamentals to formulation'. PMID:27298435

  3. Single Visit Apexification Procedure of a Traumatically Injured Tooth with a Novel Bioinductive Material (Biodentine)

    Science.gov (United States)

    Jingarwar, Mahesh Madhukar; Pathak, Anuradha

    2015-01-01

    ABSTRACT Aim of this article is to present a case wherein single visit apexification of a traumatically injured tooth was done with a bioactive material–Biodentine. An injury sustained between the ages of 6 and 14 can adversely affect pulpal health and interrupt root development. In these instances, apexification is generally the preferred treatment. A 10 years old male patient presented with coronal fracture of the left upper central incisor. Clinical and radiographic assessment showed negative pulpal sensibility and arrested apical root development. Artificial apical barrier induction with Biodentine followed by endodontic treatment and prosthetic rehabilitation was decided as the line of treatment. To conclude, this bioactive and biocompatible calcium-based cement can regenerate damaged dental tissues and represents a promising alternative to the conventional multivisit apexification technique. Clinical significance: Biodentine which is a biologically active cement can be an efficient alternative to the conventional apexification materials which were hitherto recommended. How to cite this article: Bajwa NK, Jingarwar MM, Pathak A. Single Visit Apexification Procedure of a Traumatically Injured Tooth with a Novel Bioinductive Material (Biodentine). Int J Clin Pediatr Dent 2015;8(1):58-61. PMID:26124583

  4. Saw-tooth cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Karatza Ageliki A

    2009-12-01

    Full Text Available Abstract We present an unusual case of cardiomyopathy in a two month old male infant with a grade-I systolic murmur. Echocardiographic examination disclosed left ventricular (LV, dysplasia with saw-tooth like inwards myocardial projections extending from the lateral walls towards the LV cavity. There was mild LV systolic dysfunction with apical hypokinesia. Cardiovascular magnetic resonance demonstrated in detail these cross bridging muscular projections originating from the inferior interventricular septum and lateral LV wall, along with areas of hypokinesis at the LV septum and apex in a noncoronary distribution, without any late gadolinium enhancement. We have termed this condition saw-tooth cardiomyopathy because of the very characteristic appearance.

  5. The Rachitic Tooth

    OpenAIRE

    Foster, Brian L.; Nociti, Francisco H.; Somerman, Martha J

    2013-01-01

    Teeth are mineralized organs composed of three unique hard tissues, enamel, dentin, and cementum, and supported by the surrounding alveolar bone. Although odontogenesis differs from osteogenesis in several respects, tooth mineralization is susceptible to similar developmental failures as bone. Here we discuss conditions fitting under the umbrella of rickets, which traditionally referred to skeletal disease associated with vitamin D deficiency but has been more recently expanded to include new...

  6. Saw-tooth cardiomyopathy

    OpenAIRE

    Karatza Ageliki A; Danias Peter G; Davlouros Periklis A; Kiaffas Maria G; Alexopoulos Dimitrios

    2009-01-01

    Abstract We present an unusual case of cardiomyopathy in a two month old male infant with a grade-I systolic murmur. Echocardiographic examination disclosed left ventricular (LV), dysplasia with saw-tooth like inwards myocardial projections extending from the lateral walls towards the LV cavity. There was mild LV systolic dysfunction with apical hypokinesia. Cardiovascular magnetic resonance demonstrated in detail these cross bridging muscular projections originating from the inferior interve...

  7. Arabidopsis CPR5 Independently Regulates Seed Germination and Postgermination Arrest of Development through LOX Pathway and ABA Signaling

    OpenAIRE

    Guilan Gao; Shengchun Zhang; Chengfeng Wang; Xiang Yang; Yaqin Wang; Xiaojun Su; Jinju Du; Chengwei Yang

    2011-01-01

    The phytohormone abscisic acid (ABA) and the lipoxygenases (LOXs) pathway play important roles in seed germination and seedling growth and development. Here, we reported on the functional characterization of Arabidopsis CPR5 in the ABA signaling and LOX pathways. The cpr5 mutant was hypersensitive to ABA in the seed germination, cotyledon greening and root growth, whereas transgenic plants overexpressing CPR5 were insensitive. Genetic analysis demonstrated that CPR5 gene may be located downst...

  8. The embryo development arrest clinicalanalysis%孕早期胚胎停止发育的临床分析

    Institute of Scientific and Technical Information of China (English)

    卜春梅

    2013-01-01

    目的:探讨孕早期胚胎停止发育的原因。方法收集2011年8月至2013年8月来我院妇产科门诊就诊的2134例孕妇信息,经超声和临床检查确诊为孕早期胚胎停止发育的108例患者为研究对象。结果孕早期胚胎停止发育的常见病因包括染色体异常、子宫异常、免疫因素、内分泌失调、生殖器感染、环境因素等。导致孕早期胚胎停止发育的主要病因为子宫异常(25.93%)、环境因素(22.22%)、内分泌失调(21.30%)。结论导致孕早期胚胎停止发育的因素较多、早发现,早预防,早治疗是诊治的关键。%Objective to investigate the causes of early pregnancy to stop development of the embryo.Methods 2011 8 to august 2013 in our hospital obstetrics and gynecology clinic 2134 cases of pregnant women information by ultrasound and clinical examination diagnosed early embryos stop development of the 108 patients for the study.Results the early embryos stop development of common causes include chromosomal abnormalities, uterine abnormalities, immune factors, endocrine disorders, genital infections, and environmental factors. The result in the ifrst trimester embryo stops growing mainly because of abnormal uterine disease (25.93%), environmental factors (22.22%), endocrine disorders (21.30%).Conclusion embryo to stop the development of many factors result in the early stages of pregnancy, early detection, early prevention, early treatment is the key to the diagnosis and treatment.

  9. Clinical measurement of tooth wear: tooth Wear Indices

    OpenAIRE

    López Frías, J.; Castellanos Cosano, Lizett; Martín González, Jenifer; Llamas Carreras, José María; Segura-Egea, Juan J.

    2012-01-01

    Attrition, erosion, and abrasion result in alterations to the tooth and manifest as tooth wear. Each classification corresponds to a different process with specific clinical features. Classifications made so far have no accurate prevalence data because the indexes do not necessarily measure a specific etiology, or because the study populations can be diverse in age and characteristics. Tooth wears (attrition, erosion and abrasion) is perceived internationally as a growing problem. However, th...

  10. Arabidopsis CPR5 independently regulates seed germination and postgermination arrest of development through LOX pathway and ABA signaling.

    Directory of Open Access Journals (Sweden)

    Guilan Gao

    Full Text Available The phytohormone abscisic acid (ABA and the lipoxygenases (LOXs pathway play important roles in seed germination and seedling growth and development. Here, we reported on the functional characterization of Arabidopsis CPR5 in the ABA signaling and LOX pathways. The cpr5 mutant was hypersensitive to ABA in the seed germination, cotyledon greening and root growth, whereas transgenic plants overexpressing CPR5 were insensitive. Genetic analysis demonstrated that CPR5 gene may be located downstream of the ABI1 in the ABA signaling pathway. However, the cpr5 mutant showed an ABA independent drought-resistant phenotype. It was also found that the cpr5 mutant was hypersensitive to NDGA and NDGA treatment aggravated the ABA-induced delay in the seed germination and cotyledon greening. Taken together, these results suggest that the CPR5 plays a regulatory role in the regulation of seed germination and early seedling growth through ABA and LOX pathways independently.

  11. MeHg Developing Exposure Causes DNA Double-Strand Breaks and Elicits Cell Cycle Arrest in Spinal Cord Cells

    Directory of Open Access Journals (Sweden)

    Fabiana F. Ferreira

    2015-01-01

    Full Text Available The neurotoxicity caused by methylmercury (MeHg is well documented; however, the developmental neurotoxicity in spinal cord is still not fully understood. Here we investigated whether MeHg affects the spinal cord layers development. Chicken embryos at E3 were treated in ovo with 0.1 μg MeHg/50 μL saline solution and analyzed at E10. Thus, we performed immunostaining using anti-γ-H2A.X to recognize DNA double-strand breaks and antiphosphohistone H3, anti-p21, and anti-cyclin E to identify cells in proliferation and cell cycle proteins. Also, to identify neuronal cells, we used anti-NeuN and anti-βIII-tubulin antibodies. After the MeHg treatment, we observed the increase on γ-H2A.X in response to DNA damage. MeHg caused a decrease in the proliferating cells and in the thickness of spinal cord layers. Moreover, we verified that MeHg induced an increase in the number of p21-positive cells but did not change the cyclin E-positive cells. A significantly high number of TUNEL-positive cells indicating DNA fragmentation were observed in MeHg-treated embryos. Regarding the neuronal differentiation, MeHg induced a decrease in NeuN expression and did not change the expression of βIII-tubulin. These results showed that in ovo MeHg exposure alters spinal cord development by disturbing the cell proliferation and death, also interfering in early neuronal differentiation.

  12. MeHg Developing Exposure Causes DNA Double-Strand Breaks and Elicits Cell Cycle Arrest in Spinal Cord Cells

    Science.gov (United States)

    Ferreira, Fabiana F.; Ammar, Dib; Bourckhardt, Gilian F.; Kobus-Bianchini, Karoline; Müller, Yara M. R.; Nazari, Evelise M.

    2015-01-01

    The neurotoxicity caused by methylmercury (MeHg) is well documented; however, the developmental neurotoxicity in spinal cord is still not fully understood. Here we investigated whether MeHg affects the spinal cord layers development. Chicken embryos at E3 were treated in ovo with 0.1 μg MeHg/50 μL saline solution and analyzed at E10. Thus, we performed immunostaining using anti-γ-H2A.X to recognize DNA double-strand breaks and antiphosphohistone H3, anti-p21, and anti-cyclin E to identify cells in proliferation and cell cycle proteins. Also, to identify neuronal cells, we used anti-NeuN and anti-βIII-tubulin antibodies. After the MeHg treatment, we observed the increase on γ-H2A.X in response to DNA damage. MeHg caused a decrease in the proliferating cells and in the thickness of spinal cord layers. Moreover, we verified that MeHg induced an increase in the number of p21-positive cells but did not change the cyclin E-positive cells. A significantly high number of TUNEL-positive cells indicating DNA fragmentation were observed in MeHg-treated embryos. Regarding the neuronal differentiation, MeHg induced a decrease in NeuN expression and did not change the expression of βIII-tubulin. These results showed that in ovo MeHg exposure alters spinal cord development by disturbing the cell proliferation and death, also interfering in early neuronal differentiation. PMID:26793240

  13. [Tooth erosion - a multidisciplinary approach].

    Science.gov (United States)

    Strużycka, Izabela; Rusyan, Ewa; Bogusławska-Kapała, Agnieszka

    2016-02-01

    During the last decades, an increasingly greater interest in dental erosion has been observed in clinical dental practice, in dental public health and in dental research because prevalence of erosive tooth wear is still increasing especially in young age group of population. Erosive tooth wear is a multifactorial etiology process characterized by progressive loss of hard dental tissue. It is defined as the exogenous and/or endogenous acids dissolution of the dental tissue, without bacterial involvement. In the development of dental erosive wear, interactions are required which include chemical, biological, behavioral, diet, time, socioeconomic, knowledge, education, and general health factors. Examples of risk groups could be patients with eating disorders, like anorexia nervosa or bulimia nervosa, gastroesophageal reflux disease, chronic alcohol abuse or dependence. Special nutrition habits groups with high consumption of soft or sport drinks, special diets like vegetarian, vegan or raw food diet, the regular intake of drugs, medications and food supplements can also increase the risk for dental erosion. Comprehensive knowledge of the different risk and protective factors is a perquisite for initiating adequate preventive measures. PMID:27000809

  14. Death in the life of a tooth

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Tucker, A. S.; Sharpe, P. T.

    2004-01-01

    Roč. 83, č. 1 (2004), s. 11-16. ISSN 0022-0345 R&D Projects: GA ČR GP204/02/P112 Institutional research plan: CEZ:AV0Z5045916 Keywords : apoptosis * tooth development Subject RIV: EA - Cell Biology Impact factor: 3.131, year: 2004

  15. Arrested development of the myxozoan parasite, Myxobolus cerebralis, in certain populations of mitochondrial 16S lineage III Tubifex tubifex

    Science.gov (United States)

    Baxa, D.V.; Kelley, G.O.; Mukkatira, K.S.; Beauchamp, K.A.; Rasmussen, C.; Hedrick, R.P.

    2008-01-01

    Laboratory populations of Tubifex tubifex from mitochondrial (mt)16S ribosomal DNA (rDNA) lineage III were generated from single cocoons of adult worms releasing the triactinomyxon stages (TAMs) of the myxozoan parasite, Myxobolus cerebralis. Subsequent worm populations from these cocoons, referred to as clonal lines, were tested for susceptibility to infection with the myxospore stages of M. cerebralis. Development and release of TAMs occurred in five clonal lines, while four clonal lines showed immature parasitic forms that were not expelled from the worm (non-TAM producers). Oligochaetes from TAM- and non-TAM-producing clonal lines were confirmed as lineage III based on mt16S rDNA and internal transcribed spacer region 1 (ITS1) sequences, but these genes did not differentiate these phenotypes. In contrast, random amplified polymorphic DNA analyses of genomic DNA demonstrated unique banding patterns that distinguished the phenotypes. Cohabitation of parasite-exposed TAM- and non-TAM-producing phenotypes showed an overall decrease in expected TAM production compared to the same exposure dose of the TAM-producing phenotype without cohabitation. These studies suggest that differences in susceptibility to parasite infection can occur in genetically similar T. tubifex populations, and their coexistence may affect overall M. cerebralis production, a factor that may influence the severity of whirling disease in wild trout populations. ?? 2007 Springer-Verlag.

  16. Arrested development of the myxozoan parasite, Myxobolus cerebralis, in certain populations of mitochondrial 16S lineage III Tubifex tubifex.

    Science.gov (United States)

    Baxa, D V; Kelley, G O; Mukkatira, K S; Beauchamp, K A; Rasmussen, C; Hedrick, R P

    2008-01-01

    Laboratory populations of Tubifex tubifex from mitochondrial (mt)16S ribosomal DNA (rDNA) lineage III were generated from single cocoons of adult worms releasing the triactinomyxon stages (TAMs) of the myxozoan parasite, Myxobolus cerebralis. Subsequent worm populations from these cocoons, referred to as clonal lines, were tested for susceptibility to infection with the myxospore stages of M. cerebralis. Development and release of TAMs occurred in five clonal lines, while four clonal lines showed immature parasitic forms that were not expelled from the worm (non-TAM producers). Oligochaetes from TAM- and non-TAM-producing clonal lines were confirmed as lineage III based on mt16S rDNA and internal transcribed spacer region 1 (ITS1) sequences, but these genes did not differentiate these phenotypes. In contrast, random amplified polymorphic DNA analyses of genomic DNA demonstrated unique banding patterns that distinguished the phenotypes. Cohabitation of parasite-exposed TAM- and non-TAM-producing phenotypes showed an overall decrease in expected TAM production compared to the same exposure dose of the TAM-producing phenotype without cohabitation. These studies suggest that differences in susceptibility to parasite infection can occur in genetically similar T. tubifex populations, and their coexistence may affect overall M. cerebralis production, a factor that may influence the severity of whirling disease in wild trout populations. PMID:17891544

  17. Nuclear Factor I-C Is Essential for Odontogenic Cell Proliferation and Odontoblast Differentiation during Tooth Root Development*

    OpenAIRE

    Lee, Dong-Seol; Park, Jong-Tae; Kim, Hyun-Man; Ko, Jea Seung; Son, Ho-Hyun; Gronostajski, Richard M; Cho, Moon-Il; Choung, Pill-Hoon; Park, Joo-Cheol

    2009-01-01

    Our previous studies have demonstrated that nuclear factor I-C (NFI-C) null mice developed short molar roots that contain aberrant odontoblasts and abnormal dentin formation. Based on these findings, we performed studies to elucidate the function of NFI-C in odontoblasts. Initial studies demonstrated that aberrant odontoblasts become dissociated and trapped in an osteodentin-like mineralized tissue. Abnormal odontoblasts exhibit strong bone sialoprotein expression but a decreased level of den...

  18. The influence of electrospun fibre scaffold orientation and nano-hydroxyapatite content on the development of tooth bud stem cells in vitro

    NARCIS (Netherlands)

    Manen, E.H. van; Zhang, W.; Walboomers, X.F.; Vazquez, B.; Yang, F.; Ji, W.; Yu, N.; Spear, D.J.; Jansen, J.A.; Yelick, P.C.

    2014-01-01

    In stem cell-based dental tissue engineering, the goal is to create tooth-like structures using scaffold materials to guide the dental stem cells. In this study, the effect of fiber alignment and hydroxyapatite content in biodegradable electrospun PLGA scaffolds have been investigated. Fiber orienta

  19. Development of the probability of return of spontaneous circulation in intervals without chest compressions during out-of-hospital cardiac arrest: an observational study

    Directory of Open Access Journals (Sweden)

    Steen Petter

    2009-02-01

    Full Text Available Abstract Background One of the factors that limits survival from out-of-hospital cardiac arrest is the interruption of chest compressions. During ventricular fibrillation and tachycardia the electrocardiogram reflects the probability of return of spontaneous circulation associated with defibrillation. We have used this in the current study to quantify in detail the effects of interrupting chest compressions. Methods From an electrocardiogram database we identified all intervals without chest compressions that followed an interval with compressions, and where the patients had ventricular fibrillation or tachycardia. By calculating the mean-slope (a predictor of the return of spontaneous circulation of the electrocardiogram for each 2-second window, and using a linear mixed-effects statistical model, we quantified the decline of mean-slope with time. Further, a mapping from mean-slope to probability of return of spontaneous circulation was obtained from a second dataset and using this we were able to estimate the expected development of the probability of return of spontaneous circulation for cases at different levels. Results From 911 intervals without chest compressions, 5138 analysis windows were identified. The results show that cases with the probability of return of spontaneous circulation values 0.35, 0.1 and 0.05, 3 seconds into an interval in the mean will have probability of return of spontaneous circulation values 0.26 (0.24–0.29, 0.077 (0.070–0.085 and 0.040(0.036–0.045, respectively, 27 seconds into the interval (95% confidence intervals in parenthesis. Conclusion During pre-shock pauses in chest compressions mean probability of return of spontaneous circulation decreases in a steady manner for cases at all initial levels. Regardless of initial level there is a relative decrease in the probability of return of spontaneous circulation of about 23% from 3 to 27 seconds into such a pause.

  20. Cardiac Arrest-Induced Global Brain Hypoxia-Ischemia during Development Affects Spontaneous Activity Organization in Rat Sensory and Motor Thalamocortical Circuits during Adulthood.

    Science.gov (United States)

    Shoykhet, Michael; Middleton, Jason W

    2016-01-01

    Normal maturation of sensory information processing in the cortex requires patterned synaptic activity during developmentally regulated critical periods. During early development, spontaneous synaptic activity establishes required patterns of synaptic input, and during later development it influences patterns of sensory experience-dependent neuronal firing. Thalamocortical neurons occupy a critical position in regulating the flow of patterned sensory information from the periphery to the cortex. Abnormal thalamocortical inputs may permanently affect the organization and function of cortical neuronal circuits, especially if they occur during a critical developmental window. We examined the effect of cardiac arrest (CA)-associated global brain hypoxia-ischemia in developing rats on spontaneous and evoked firing of somatosensory thalamocortical neurons and on large-scale correlations in the motor thalamocortical circuit. The mean spontaneous and sensory-evoked firing rate activity and variability were higher in CA injured rats. Furthermore, spontaneous and sensory-evoked activity and variability were correlated in uninjured rats, but not correlated in neurons from CA rats. Abnormal activity patterns of ventroposterior medial nucleus (VPm) neurons persisted into adulthood. Additionally, we found that neurons in the entopeduncular nucleus (EPN) in the basal ganglia had lower firing rates yet had higher variability and higher levels of burst firing after injury. Correlated levels of power in local field potentials (LFPs) between the EPN and the motor cortex (MCx) were also disrupted by injury. Our findings indicate that hypoxic-ischemic injury during development leads to abnormal spontaneous and sensory stimulus-evoked input patterns from thalamus to cortex. Abnormal thalamic inputs likely permanently and detrimentally affect the organization of cortical circuitry and processing of sensory information. Hypoxic-ischemic injury also leads to abnormal single neuron and

  1. Local Synthesis and Tooth Contact Analysis of Face-Milled, Uniform Tooth Height Spiral Bevel Gears

    Science.gov (United States)

    Litvin, F. L.; Wang, A. G.

    1996-01-01

    Face-milled spiral bevel gears with uniform tooth height are considered. An approach is proposed for the design of low-noise and localized bearing contact of such gears. The approach is based on the mismatch of contacting surfaces and permits two types of bearing contact either directed longitudinally or across the surface to be obtained. Conditions to avoid undercutting were determined. A Tooth Contact Analysis (TCA) was developed. This analysis was used to determine the influence of misalignment on meshing and contact of the spiral bevel gears. A numerical example that illustrates the theory developed is provided.

  2. Cardiac arrest – cardiopulmonary resuscitation

    Directory of Open Access Journals (Sweden)

    Basri Lenjani

    2014-01-01

    Conclusions: All survivors from cardiac arrest have received appropriate medical assistance within 10 min from attack, which implies that if cardiac arrest occurs near an institution health care (with an opportunity to provide the emergent health care the rate of survival is higher.

  3. Enhanced Prediction of Gear Tooth Surface Fatigue Life Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Sentient will develop an enhanced prediction of gear tooth surface fatigue life with rigorous analysis of the tribological phenomena that contribute to pitting...

  4. The lateral enamel lamina--component of tooth primordia in selected mammalian species.

    Science.gov (United States)

    Witter, K; Matulová, P; Mísek, I

    2002-01-01

    The lateral enamel lamina (LEL) is a part of the enamel organ, which is probably not involved in tooth formation. It represents, besides the "stalk" of the tooth primordium, a second interconnection between enamel organ and oral epithelium or vestibular lamina. We detected the LEL in the sheep (Ovis aries), the dolphin (Stenella attenuata), and the vole (Microtus agrestis) by light microscopy and computer-aided three-dimensional reconstruction. The LEL could be found in cap to bell stage tooth primordia, most clearly in slowly developing tooth germs. LEL-like structures have been furthermore described or depicted in tooth germs of the mouse, the elk (Alces alces), the dugong (Dugong dugong), the elephant (Loxodonta africana), and the human. Probably it is a part of all mammalian tooth primordia that undergoes regression during morphogenesis of the enamel organ. As a reducing structure, it should be considered in studies of tooth development. PMID:12494916

  5. Based on labview of zinc oxide lightning arrester test system development%基于labview的氧化锌避雷器测试系统研制

    Institute of Scientific and Technical Information of China (English)

    杜玉霞; 车军

    2012-01-01

    This system the application of virtual instrument technology, the use of graphics programming software, design a kind of based on ipc of zinc oxide lightning arrester test bench, and makes the zinc oxide lightning arrester measurement more convenient, more accurate, and automatic judgment qualified or not, and to test results are file and print.%本系统应用虚拟仪器技术,利用图形编程软件,设计了一种基于工控机的氧化锌避雷器试验台,并使得氧化锌避雷器的测量更方便、更准确、并自动判断合格与否,并可以对测试结果进行存档、打印.

  6. Cell adhesion molecules during odontogenesis and tooth-related diseases

    OpenAIRE

    Heymann, Robert

    2002-01-01

    Cell adhesion molecules play essential roles in the development and disease of tooth and oral structures, as well as in the maintenance of adult tissue structure/function. It has been shown that different types of cell adhesion molecules (CAMs) play an important part in craniofacial development when ectomesenchymal cells migrate from the neural list to the primitive oral cavity, giving rise to the palatal processes and tooth germs. The role of CAMs in craniofacial developmen...

  7. Partial tooth gear bearings

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  8. Applications of surface-surface matching algorithms for determination of orthodontic tooth movements.

    Science.gov (United States)

    Keilig, L; Piesche, K; Jäger, A; Bourauel, C

    2003-01-01

    Orthodontic tooth movements are described as the differences between initial and final tooth positions. A computer based method for determination of tooth movements for different treatment methods was developed. A total of 20 casts of the upper jaw of patients treated with tooth positioners or fixed appliances were used as a basis for this study. Tooth movement was analysed on casts before (Ci) and after treatment (Cf). The casts were digitized either with a COMT or 3D laser scanning systems. After digitization, the models were superimposed in the palate by using a surface-surface matching algorithm. Tooth surfaces of the orthodontically moved teeth were segmented and determination of tooth movement was accomplished by matching the moved teeth from Ci to Cf. The resulting transformations delivered three dimensional information on translations and rotations. An accuracy of 0.2 mm in translations and 1 degree in rotations could be demonstrated, showing the different efficiency of treatment schemes. PMID:14675956

  9. Functional constraints on tooth morphology in carnivorous mammals

    Directory of Open Access Journals (Sweden)

    Smits Peter D

    2012-08-01

    Full Text Available Abstract Background The range of potential morphologies resulting from evolution is limited by complex interacting processes, ranging from development to function. Quantifying these interactions is important for understanding adaptation and convergent evolution. Using three-dimensional reconstructions of carnivoran and dasyuromorph tooth rows, we compared statistical models of the relationship between tooth row shape and the opposing tooth row, a static feature, as well as measures of mandibular motion during chewing (occlusion, which are kinetic features. This is a new approach to quantifying functional integration because we use measures of movement and displacement, such as the amount the mandible translates laterally during occlusion, as opposed to conventional morphological measures, such as mandible length and geometric landmarks. By sampling two distantly related groups of ecologically similar mammals, we study carnivorous mammals in general rather than a specific group of mammals. Results Statistical model comparisons demonstrate that the best performing models always include some measure of mandibular motion, indicating that functional and statistical models of tooth shape as purely a function of the opposing tooth row are too simple and that increased model complexity provides a better understanding of tooth form. The predictors of the best performing models always included the opposing tooth row shape and a relative linear measure of mandibular motion. Conclusions Our results provide quantitative support of long-standing hypotheses of tooth row shape as being influenced by mandibular motion in addition to the opposing tooth row. Additionally, this study illustrates the utility and necessity of including kinetic features in analyses of morphological integration.

  10. Tooth fragment reattachment technique on a pluri traumatized tooth

    OpenAIRE

    Giuseppe Lo Giudice; Frank Lipari; Angelo Lizio; Gabriel Cervino; Marco Cicciù

    2012-01-01

    This case report describes and analyses a tooth fragment reattachment technique used to resolve crown fractures of the anterior teeth. This treatment allows a conservative approach to traumatic coronal lesions offering a better possibility of maintaining aesthetics and function. The authors have illustrated here a clinical case of a fractured incisor. This case is characterized by several traumas on the same tooth that required different therapeutic solutions. We used an easy and ultra-conser...

  11. Making a tooth: growth factors, transcription factors, and stem cells

    Institute of Scientific and Technical Information of China (English)

    Yah Ding ZHANG; Zhi CHEN; Yi Qiang SONG; Chao LIU; Yi Ping CHEN

    2005-01-01

    Mammalian tooth development is largely dependent on sequential and reciprocal epithelial-mesenchymal interactions.These processes involve a series of inductive and permissive interactions that result in the determination, differentiation,and organization of odontogenic tissues. Multiple signaling molecules, including BMPs, FGFs, Shh, and Wnt proteins,have been implicated in mediating these tissue interactions. Transcription factors participate in epithelial-mesenchymal interactions via linking the signaling loops between tissue layers by responding to inductive signals and regulating the expression of other signaling molecules. Adult stem cells are highly plastic and multipotent. These cells including dental pulp stem cells and bone marrow stromal cells could be reprogrammed into odontogenic fate and participated in tooth formation. Recent progress in the studies of molecular basis of tooth development, adult stem cell biology, and regeneration will provide fundamental knowledge for the realization of human tooth regeneration in the near future.

  12. Tooth fragment reattachment technique on a pluri traumatized tooth

    Directory of Open Access Journals (Sweden)

    Giuseppe Lo Giudice

    2012-01-01

    Full Text Available This case report describes and analyses a tooth fragment reattachment technique used to resolve crown fractures of the anterior teeth. This treatment allows a conservative approach to traumatic coronal lesions offering a better possibility of maintaining aesthetics and function. The authors have illustrated here a clinical case of a fractured incisor. This case is characterized by several traumas on the same tooth that required different therapeutic solutions. We used an easy and ultra-conservative technique without any tooth preparation in the first and third traumatic injuries. In the second trauma, a direct restoration of the fractured tooth was performed. The adhesive reattachment is a simple system to achieve good aesthetic and functional results.Our clinical experiences demonstrated that, when tooth and fragment margins are intact, the reattachment technique without any tooth preparation is a simple and predictable procedure. Quality of adhesion is shown by the retention of the reattached fragment in the second trauma that caused only partial enamel fractures.

  13. Role of Homeobox Genes in Tooth Morphogenesis: A Review

    OpenAIRE

    Suryadeva, Sreevalli; Khan, Mohammadi Begum

    2015-01-01

    In oral cavity, disturbances due to genetic alterations may range from lack of tooth development to morphological defects. Due to technical advances in genetic engineering and molecular biology, valuable information regarding dentofacial growth could be studied in detailed manner. This helped us to explain the aetiology and pathogenesis of many dentofacial disorders. The success in treatment lies first in determining the aetiology of tooth anomalies and finally differentiating the effect of g...

  14. Stem cell-based biological tooth repair and regeneration

    OpenAIRE

    Volponi, Ana Angelova; Pang, Yvonne; Sharpe, Paul T.

    2010-01-01

    Teeth exhibit limited repair in response to damage, and dental pulp stem cells probably provide a source of cells to replace those damaged and to facilitate repair. Stem cells in other parts of the tooth, such as the periodontal ligament and growing roots, play more dynamic roles in tooth function and development. Dental stem cells can be obtained with ease, making them an attractive source of autologous stem cells for use in restoring vital pulp tissue removed because of infection, in regene...

  15. NSAIDs in orthodontic tooth movement

    Directory of Open Access Journals (Sweden)

    Muthukumar Karthi

    2012-01-01

    Full Text Available Orthodontic tooth movement is basically a biological response toward a mechanical force. The movement is induced by prolonged application of controlled mechanical forces, which create pressure and tension zones in the periodontal ligament and alveolar bone, causing remodeling of tooth sockets. Orthodontists often prescribe drugs to manage pain from force application to biologic tissues. Nonsteroidal anti-inflammatory drugs (NSAIDs are the drugs usually prescribed. NSAIDs block prostaglandin synthesis and result in slower tooth movement. Prostaglandins have been found to play a direct role in bone resorption. Aspirin, acetaminophen, ibuprofen, diclofenac, vadecoxib, and celecoxib are the commonly prescribed drugs. Acetaminophen is the drug of choice for orthodontic pain without affecting orthodontic tooth movement.

  16. Broken or knocked out tooth

    Science.gov (United States)

    Pfenninger JL, Fowlder GC. Management of dental injuries and reimplantation of an avulsed tooth. In: Pfenninger JL, Fowlder GC, eds. Pfenninger & Fowler's Procedures for Primary Care . 3rd ed. Philadelphia, PA: Elsevier Mosby; 2011:chap 81

  17. Atypical Odontalgia (Phantom Tooth Pain)

    Science.gov (United States)

    ... site where teeth have been extracted or following endodontic treatment, without an identifiable cause. Over time, the ... of dental procedure such as having a root canal or tooth extraction. On occasion, the pain can ...

  18. Early myoclonic status and outcome after cardiorespiratory arrest

    OpenAIRE

    Morris, H; Howard, R; Brown, P.

    1998-01-01

    It has been suggested that early myoclonic status after cardiorespiratory arrest is an agonal event.1 Here we describe three cases who developed early myoclonic status during a coma after cardiorespiratory arrest due to acute asthma. As consciousness improved, each patient developed Lance-Adams type multifocal myoclonus, but the eventual outcome was satisfactory. Only one patient needed assistance to walk, and all three were self caring. One patient had persistent dyscalc...

  19. Crack arrest saturation model under combined electrical and mechanical loadings

    OpenAIRE

    R.R. Bhargava; A. Setia

    2009-01-01

    Purpose: The investigation aims at proposing a model for cracked piezoelectric strip which is capable to arrest the crack.Design/methodology/approach: Under the combined effect of electrical and mechanical loadings applied at the edges of the strip, the developed saturation zone is produced at each tip of the crack. To arrest further opening of the crack, the rims of the developed saturation zones are subjected to in-plane cohesive, normal uniform constant saturation point electrical displace...

  20. Electron paramagnetic resonance biophysical radiation dosimetry with tooth enamel

    International Nuclear Information System (INIS)

    This thesis deals with the advancements made in the field of Electron Paramagnetic Resonance (EPR) for biophysical dosimetry with tooth enamel for accident, emergency, and retrospective radiation dose reconstruction. A methodology has been developed to measure retrospective radiation exposures in human tooth enamel. This entails novel sample preparation procedures with minimum mechanical treatment to reduce the preparation induced uncertainties, establish optimum measurement conditions inside the EPR cavity, post-process the measured spectrum with functional simulation of dosimetric and other interfering signals, and reconstruct dose. By using this technique, retrospective gamma exposures as low as 80±30 mGy have been successfully deciphered. The notion of dose modifier was introduced in EPR biodosimetry for low dose measurements. It has been demonstrated that by using the modified zero added dose (MZAD) technique for low radiation exposures, doses in 100 mGy ranges can be easily reconstructed in teeth that were previously thought useless for EPR dosimetry. Also, the use of a dose modifier makes robust dose reconstruction possible for higher radiation exposures. The EPR dosimetry technique was also developed for tooth samples extracted from rodents, which represent small tooth sizing. EPR doses in the molars, extracted from the mice irradiated with whole body exposures, were reassessed and shown to be correct within the experimental uncertainty. The sensitivity of human tooth enamel for neutron irradiation, obtained from the 3 MV McMaster K.N. Van de Graaff accelerator, was also studied. For the first time this work has shown that the neutron sensitivity of the tooth enamel is approximately 1/10th of the equivalent gamma sensitivity. Parametric studies for neutron dose rate and neutron energy within the available range of the accelerator, showed no impact on the sensitivity of the tooth enamel. Therefore, tooth enamel can be used as a dosimeter for both neutrons

  1. ROLE OF BACTERIA IN THE TOOTH ABSCESS: A MINI REVIEW

    Directory of Open Access Journals (Sweden)

    Biswajit Batabyal

    2013-02-01

    Full Text Available A tooth abscess or root abscess is pus enclosed in the tissues of the jaw bone at the apex of an infected tooth's root(s. Usually the abscess originates from a bacterial infection that has accumulated in the soft, often dead, pulp of the tooth. This can be caused by untreated tooth decay, cracked teeth or extensive periodontal disease. A failed root canal treatment may also create a similar abscess. Recently developed molecular methods have made it possible to characterise mixed micro flora in their entirety, including the substantial numbers of uncultivable bacteria. This paper will review the current literature regarding the molecular techniques used to identify uncultivable bacteria from dental abscess.

  2. Juvenile Arrests, 1998. Juvenile Justice Bulletin.

    Science.gov (United States)

    Snyder, Howard N.

    This report provides a summary and analysis of national and state juvenile arrest data in the United States. In 1998, law enforcement agencies made an estimated 2.6 million arrests of persons under age 18. Federal Bureau of Investigations statistics indicate that juveniles account for 18% of all arrests, and 17% of all violent crime arrests in…

  3. 33 CFR 154.822 - Detonation arresters, flame arresters, and flame screens.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Detonation arresters, flame... BULK Vapor Control Systems § 154.822 Detonation arresters, flame arresters, and flame screens. (a) Each detonation arrester required by this part must: (1) Be capable of arresting a detonation from either side...

  4. Autocrine and paracrine Shh signaling are necessary for tooth morphogenesis, but not tooth replacement in snakes and lizards (Squamata).

    Science.gov (United States)

    Handrigan, Gregory R; Richman, Joy M

    2010-01-01

    Here we study the role of Shh signaling in tooth morphogenesis and successional tooth initiation in snakes and lizards (Squamata). By characterizing the expression of Shh pathway receptor Ptc1 in the developing dentitions of three species (Eublepharis macularius, Python regius, and Pogona vitticeps) and by performing gain- and loss-of-function experiments, we demonstrate that Shh signaling is active in the squamate tooth bud and is required for its normal morphogenesis. Shh apparently mediates tooth morphogenesis by separate paracrine- and autocrine-mediated functions. According to this model, paracrine Shh signaling induces cell proliferation in the cervical loop, outer enamel epithelium, and dental papilla. Autocrine signaling within the stellate reticulum instead appears to regulate cell survival. By treating squamate dental explants with Hh antagonist cyclopamine, we induced tooth phenotypes that closely resemble the morphological and differentiation defects of vestigial, first-generation teeth in the bearded dragon P. vitticeps. Our finding that these vestigial teeth are deficient in epithelial Shh signaling further corroborates that Shh is needed for the normal development of teeth in snakes and lizards. Finally, in this study, we definitively refute a role for Shh signaling in successional dental lamina formation and conclude that other pathways regulate tooth replacement in squamates. PMID:19850027

  5. Radiosterilization of tooth pastes EF, MB, LK

    International Nuclear Information System (INIS)

    The effect of decontaminating doses of gamma rays (60Co, 10 Kr - 1.5 Mr) on the quality and biological activity of tooth pastes is studied. The radioresistance factors D10 of the dominating microorganisms in the studied pastes, namely Bac. subtilis, Staph. epidermidis, S. lutea, Ps. aeruginosa, Pen. notatum, Pen. chrysogenum, Asp. niger, C. parapsilosis, are determined. Ps aeruginosa appears to show the highest radiosensitivity - D10 = 20 Kr. The irradiation in the range 500 Kr - 1.5 Mr reveals that Ps. aeruginosa are inactivated with doses of 750 Kr while the inactivation of sporebearing bacteria and grampositive microorganisms starts at doses above 1 Mr. The lower values of radioresistance factors observed as compared to that established by the authors for cosmetic preparations henna and starch are due to radiosensitizing of microorganisms in a medium with higher water content. The radiolytic effect of water causes changes in consistency, odour, taste and colour of the tooth pastes and for that reason the radiosterilization of tooth pastes is not recommended. A mathematical model for irradiation of products contaminated with a variety of microorganisms is developed. Bac. subtilis - the most frequent and radioresistant pollutant - is suggested as a standard in selecting the proper sterilization procedure and in checking the efficiency of irradiation. 3 tabs, 3 figs, 6 refs

  6. An automatic tooth preparation technique: A preliminary study.

    Science.gov (United States)

    Yuan, Fusong; Wang, Yong; Zhang, Yaopeng; Sun, Yuchun; Wang, Dangxiao; Lyu, Peijun

    2016-01-01

    The aim of this study is to validate the feasibility and accuracy of a new automatic tooth preparation technique in dental healthcare. An automatic tooth preparation robotic device with three-dimensional motion planning software was developed, which controlled an ultra-short pulse laser (USPL) beam (wavelength 1,064 nm, pulse width 15 ps, output power 30 W, and repeat frequency rate 100 kHz) to complete the tooth preparation process. A total of 15 freshly extracted human intact first molars were collected and fixed into a phantom head, and the target preparation shapes of these molars were designed using customised computer-aided design (CAD) software. The accuracy of tooth preparation was evaluated using the Geomagic Studio and Imageware software, and the preparing time of each tooth was recorded. Compared with the target preparation shape, the average shape error of the 15 prepared molars was 0.05-0.17 mm, the preparation depth error of the occlusal surface was approximately 0.097 mm, and the error of the convergence angle was approximately 1.0°. The average preparation time was 17 minutes. These results validated the accuracy and feasibility of the automatic tooth preparation technique. PMID:27125874

  7. An automatic tooth preparation technique: A preliminary study

    Science.gov (United States)

    Yuan, Fusong; Wang, Yong; Zhang, Yaopeng; Sun, Yuchun; Wang, Dangxiao; Lyu, Peijun

    2016-04-01

    The aim of this study is to validate the feasibility and accuracy of a new automatic tooth preparation technique in dental healthcare. An automatic tooth preparation robotic device with three-dimensional motion planning software was developed, which controlled an ultra-short pulse laser (USPL) beam (wavelength 1,064 nm, pulse width 15 ps, output power 30 W, and repeat frequency rate 100 kHz) to complete the tooth preparation process. A total of 15 freshly extracted human intact first molars were collected and fixed into a phantom head, and the target preparation shapes of these molars were designed using customised computer-aided design (CAD) software. The accuracy of tooth preparation was evaluated using the Geomagic Studio and Imageware software, and the preparing time of each tooth was recorded. Compared with the target preparation shape, the average shape error of the 15 prepared molars was 0.05–0.17 mm, the preparation depth error of the occlusal surface was approximately 0.097 mm, and the error of the convergence angle was approximately 1.0°. The average preparation time was 17 minutes. These results validated the accuracy and feasibility of the automatic tooth preparation technique.

  8. Permanent tooth calcification in chimpanzees (Pan troglodytes): patterns and polymorphisms.

    Science.gov (United States)

    Kuykendall, K L; Conroy, G C

    1996-01-01

    Tooth calcification is an important developmental marker for use in constructing models for early hominid life history, particularly for its application to the fossil record. As chimpanzees are commonly utilized in interspecific comparisons in such research, this study aims to improve available baseline data for tooth calcification patterns in chimpanzees (Pan troglodytes), and to quantify basic patterns and polymorphisms. We present an analysis of developmental patterns for the left mandibular dentition (I1-M3) based on intraoral radiographs obtained from a cross-sectional sample of chimpanzees (58 males, 60 females) housed at LEMSIP (NYU Medical Center) and Yerkes (Emory University). No significant differences with previous descriptions of the basic sequences of tooth calcification in chimpanzees were found, but variation in such patterns was documented for the first time. In the overall sequence, polymorphisms between the canine and the group (M2 P4 P3) reached significant levels. This is due to the relative delay in canine crown formation compared to other teeth. Differences in the basic sequence between males and females were recorded, but are due to minor shifts in the percentages of occurrence for polymorphic sequences which are common to both genders. Perhaps our most important findings are that a) different polymorphic sequences occur in tooth calcification and tooth emergence in chimpanzees, and b) developmental relationships among teeth fluctuate throughout tooth calcification. Thus, characterizations of dental developmental patterns based on particular stages of development cannot necessarily be extrapolated to other stages without supporting data. PMID:8928717

  9. Development of ISRMS for readability of the text of informed consent for tooth extraction%拔牙知情同意书文本易读性ISRMS的开发研究

    Institute of Scientific and Technical Information of China (English)

    王春燕; 虎斌; 马东

    2011-01-01

    介绍了利用Microsoft Office Access对象、窗体控件、ActiveX控件以及Microsoft Visual Basic for Applications(VBA)等功能优势,以拔牙知情同意为模型,开发主观评价医疗知情同意书文本易读性的信息化系统(ISRMS).指出该系统实现了主观评价操作、实验数据同步收集和实验数据分析的计算机信息化,引入了ActiveX控件形式的视觉模拟评分法量规和临床电子牙位记录工具.%We developed the Information-based Subjective Readability Measuring System (ISRMS) for readability of the text of informed consent for tooth extraction by utilizing the advantages of Microsoft Office Access, window control, ActiveX control, and Microsoft Visual Basic for Applications (VBA). This system has realized subjective evaluation, synchronous collection of experiment data, and analysis of experiment data, introduced the visual analogue scale in the form of ActiveX control and the tool for recording clinical electronic tooth position.

  10. Autogenous transplantation of mandibular third molar to replace tooth with vertical root fracture

    OpenAIRE

    Asgary, Saeed

    2009-01-01

    Autogenous tooth transplantation (ATT) can be considered when there is a hopeless molar tooth and suitable donor present. This report presents an unconventional case of successful ATT of a third molar replacing the adjacent fractured second molar in a 33 year old woman. This wisdom tooth had completely developed roots. Root-end filling with Calcium Enriched Mixture (CEM) cement was performed in the third molar. The second molar was extracted non-traumatically without any bone removal; the wis...

  11. Tooth polishing: The current status

    Directory of Open Access Journals (Sweden)

    Madhuri Alankar Sawai

    2015-01-01

    Full Text Available Healthy teeth and gums make a person feel confident and fit. As people go about their daily routines and with different eating and drinking habits, the tooth enamel turns yellowish or gets stained. Polishing traditionally has been associated with the prophylaxis procedure in most dental practices, which patients know and expect. However, with overzealous use of polishing procedure, there is wearing of the superficial tooth structure. This would lead to more accumulation of local deposits. Also, it takes a long time for the formation of the fluoride-rich layer of the tooth again. Hence, now-a-days, polishing is not advised as a part of routine oral prophylaxis procedure but is done selectively based on the patients′ need. The article here, gives an insight on the different aspects of the polishing process along with the different methods and agents used for the same.

  12. Primary culprit for tooth loss!!

    Science.gov (United States)

    Nuvvula, Sailavanya; Chava, Vijay Kumar; Nuvvula, Sivakumar

    2016-01-01

    Aim: In order to facilitate planning for dental health services and to progress strategies to continue the reduction in tooth loss, it is important to identify the factors that result in such loss. therefore the aim of the study is to investigate the major cause for tooth extraction. Objective: to examine whether the major reason for tooth extraction is dental caries or periodontal disease. Materials and Methods: The study is carried out among the dental practitioners in our district. A questionnaire containing 10 items was distributed to the dental practitioners, which included age, gender, no of teeth indicated for extraction, the reason for extraction, and the periodontal parameters that are involved with the extracted tooth and were requested to complete the form on every extraction they were to undertake. the study form was collected at the end of the study period and data was subjected to statistical analysis. Results: A total of 502 patients were enrolled during the study period, and a total of 1055 teeth were extracted for several reasons. we found that 51.14%extractions are due to dental caries in case of 20-30years age groups, which is more when compared to tooth loss due to periodontal diseases in this age group. whereas in case of >40years of age group periodontal diseases account for 54.11%, and dental caries accounts for only 29.11%. Showing more teeth were lost due to periodontal disease. Conclusion: therefore we concluded that, caries is the dominant reason for extraction in patients with 20–30 years of age while periodontal disease accounts for the majority of tooth extraction in patients older than 40 years. PMID:27143841

  13. On gear tooth stiffness evaluation

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Jørgensen, Martin Felix

    2014-01-01

    The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation and...... secondly the size of the contact. In the FE calculation the true gear tooth root profile is applied. The meshing stiffnesses of gears are highly non-linear, it is however found that the stiffness of an individual tooth can be expressed in a linear form assuming that the contact width is constant. © 2014...

  14. Twist1 Is Essential for Tooth Morphogenesis and Odontoblast Differentiation.

    Science.gov (United States)

    Meng, Tian; Huang, Yanyu; Wang, Suzhen; Zhang, Hua; Dechow, Paul C; Wang, Xiaofang; Qin, Chunlin; Shi, Bing; D'Souza, Rena N; Lu, Yongbo

    2015-12-01

    Twist1 is a basic helix-loop-helix-containing transcription factor that is expressed in the dental mesenchyme during the early stages of tooth development. To better delineate its roles in tooth development, we generated Twist1 conditional knockout embryos (Twist2(Cre) (/+);Twist1(fl/fl)) by breeding Twist1 floxed mice (Twist1(fl/fl)) with Twist2-Cre recombinase knockin mice (Twist2(Cre) (/+)). The Twist2(Cre) (/+);Twist1(fl/fl) embryos formed smaller tooth germs and abnormal cusps during early tooth morphogenesis. Molecular and histological analyses showed that the developing molars of the Twist2(Cre) (/+);Twist1(fl/fl) embryos had reduced cell proliferation and expression of fibroblast growth factors 3, 4, 9, and 10 and FGF receptors 1 and 2 in the dental epithelium and mesenchyme. In addition, 3-week-old renal capsular transplants of embryonic day 18.5 Twist2(Cre) (/+);Twist1(fl/fl) molars showed malformed crowns and cusps with defective crown dentin and enamel. Immunohistochemical analyses revealed that the implanted mutant molars had defects in odontoblast differentiation and delayed ameloblast differentiation. Furthermore, in vitro ChIP assays demonstrated that Twist1 was able to bind to a specific region of the Fgf10 promoter. In conclusion, our findings suggest that Twist1 plays crucial roles in regulating tooth development and that it may exert its functions through the FGF signaling pathway. PMID:26487719

  15. Hypothermia improves outcome from cardiac arrest.

    Science.gov (United States)

    Bernard, S A

    2005-12-01

    Out-of-hospital cardiac arrest is common and patients who are initially resuscitated by ambulance officers and transported to hospital are usually admitted to the intensive care unit (ICU). In the past, the treatment in the ICU consisted of supportive care only, and most patients remained unconscious due to the severe anoxic neurological injury. It was this neurological injury rather than cardiac complications that caused the high rate of morbidity and mortality. However, in the early 1990's, a series of animal experiments demonstrated convincingly that mild hypothermia induced after return of spontaneous circulation and maintained for several hours dramatically reduced the severity of the anoxic neurological injury. In the mid-1990's, preliminary human studies suggested that mild hypothermia could be induced and maintained in post-cardiac arrest patients without an increase in the rate of cardiac or other complications. In the late 1990's, two prospective, randomised, controlled trials were conducted and the results confirmed the animal data that mild hypothermia induced after resuscitation and maintained for 12 - 24 hours dramatically improved neurological and overall outcomes. On the basis of these studies, mild hypothermia was endorsed in 2003 by the International Liaison Committee on Resuscitation as a recommended treatment for comatose patients with an initial cardiac rhythm of ventricular fibrillation. However, the application of this therapy into routine clinical critical care practice has been slow. The reasons for this are uncertain, but may relate to the relative complexity of the treatment, unfamiliarity with the pathophysiology of hypothermia, lack of clear protocols and/or uncertainty of benefit in particular patients. Therefore, recent research in this area has focused on the development of feasible, inexpensive techniques for the early, rapid induction of mild hypothermia after cardiac arrest. Currently, the most promising strategy is a rapid

  16. Epithelial topography for repetitive tooth formation

    Directory of Open Access Journals (Sweden)

    Marcia Gaete

    2015-12-01

    Full Text Available During the formation of repetitive ectodermally derived organs such as mammary glands, lateral line and teeth, the tissue primordium iteratively initiates new structures. In the case of successional molar development, new teeth appear sequentially in the posterior region of the jaw from Sox2+ cells in association with the posterior aspect of a pre-existing tooth. The sequence of molar development is well known, however, the epithelial topography involved in the formation of a new tooth is unclear. Here, we have examined the morphology of the molar dental epithelium and its development at different stages in the mouse in vivo and in molar explants. Using regional lineage tracing we show that within the posterior tail of the first molar the primordium for the second and third molar are organized in a row, with the tail remaining in connection with the surface, where a furrow is observed. The morphology and Sox2 expression of the tail retains characteristics reminiscent of the earlier stages of tooth development, such that position along the A-P axes of the tail correlates with different temporal stages. Sox9, a stem/progenitor cell marker in other organs, is expressed mainly in the suprabasal epithelium complementary with Sox2 expression. This Sox2 and Sox9 expressing molar tail contains actively proliferating cells with mitosis following an apico-basal direction. Snail2, a transcription factor implicated in cell migration, is expressed at high levels in the tip of the molar tail while E-cadherin and laminin are decreased. In conclusion, our studies propose a model in which the epithelium of the molar tail can grow by posterior movement of epithelial cells followed by infolding and stratification involving a population of Sox2+/Sox9+ cells.

  17. Tooth Avulsion in the School Setting

    Science.gov (United States)

    Krause-Parello, Cheryl A.

    2005-01-01

    Tooth avulsions occur when a tooth is displaced from its socket. Tooth avulsions are common dental injuries that may occur before, during, or after school. Therefore, it is essential that school nurses be well prepared to intervene when such a dental emergency arises. It is also imperative that school nurses and school personnel are fully equipped…

  18. 21 CFR 872.3920 - Porcelain tooth.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Porcelain tooth. 872.3920 Section 872.3920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3920 Porcelain tooth. (a) Identification. A porcelain tooth is a prefabricated device made of...

  19. Exposure to the Contraceptive Progestin, Gestodene, Alters Reproductive Behavior, Arrests Egg Deposition, and Masculinizes Development in the Fathead Minnow (Pimephales promelas).

    Science.gov (United States)

    Frankel, Tyler E; Meyer, Michael T; Kolpin, Dana W; Gillis, Amanda B; Alvarez, David A; Orlando, Edward F

    2016-06-01

    Endogenous progestogens and pharmaceutical progestins enter the environment through wastewater treatment plant effluent and agricultural field runoff. Lab studies demonstrate strong, negative exposure effects of these chemicals on aquatic vertebrate reproduction. Behavior can be a sensitive, early indicator of exposure to environmental contaminants associated with altered reproduction yet is rarely examined in ecotoxicology studies. Gestodene is a human contraceptive progestin and a potent activator of fish androgen receptors. Our objective was to test the effects of gestodene on reproductive behavior and associated egg deposition in the fathead minnow. After only 1 day, males exposed to ng/L of gestodene were more aggressive and less interested in courtship and mating, and exposed females displayed less female courtship behavior. Interestingly, 25% of the gestodene tanks contained a female that drove the male out of the breeding tile and displayed male-typical courtship behaviors toward the other female. Gestodene decreased or arrested egg deposition with no observed gonadal histopathology. Together, these results suggest that effects on egg deposition are primarily due to altered reproductive behavior. The mechanisms by which gestodene disrupts behavior are unknown. Nonetheless, the rapid and profound alterations of the reproductive biology of gestodene-exposed fish suggest that wild populations could be similarly affected. PMID:27129041

  20. Charcot-Marie-Tooth Disease

    Science.gov (United States)

    Charcot-Marie-Tooth disease (CMT) is a group of genetic nerve disorders. It is named after the three doctors who first identified it. ... a nerve biopsy. There is no cure. The disease can be so mild you don't realize ...

  1. Wide plate crack arrest testing

    International Nuclear Information System (INIS)

    To predict the behavior of a nuclear pressure vessel undergoing pressurized thermal shock, certain information on dynamic crack propagation and arrest is required. The purpose of the work described is to provide such data on wide plates fracturing at temperatures up to the upper shelf region. Four tests have been completed on the 26 MN Universal Testing Machine at NBS. The specimens are to be fractured in a thermal gradient that, in the most extreme case, might extend from -1000C to 2000 across the 1 meter specimen width. This is done so that the crack will initiate in a cold, brittle region and arrest in a hot, tough region. An important part of this study is data acquisition from the numerous strain gages, thermocouples, timing wires, crack mouth opening displacement gages, and acoustic emission transducers that are mounted on the specimen. Each test has been different with respect to conditions of testing, specimen configuration, and instrumentation used. The progressive changes in test procedure represent attempts to obtain the desired crack run and arrest behavior and to improve upon the quality of the data collected. In particular, efforts were made to initiate crack propagation at lower stress intensity factors. Also, strain gage combinations and locations were optimized to better deduce the crack position as a function of time. Another result of great interest that can be deduced from these tests is the initiation of fracture toughness and the arrest toughness

  2. Sudden Cardiac Arrest (SCA) Risk Assessment

    Science.gov (United States)

    ... Find a Specialist Share Twitter Facebook SCA Risk Assessment Sudden Cardiac Arrest (SCA) occurs abruptly and without ... of all ages and health conditions. Start Risk Assessment The Sudden Cardiac Arrest (SCA) Risk Assessment Tool ...

  3. Crack propagation and arrest in CFRP materials with strain softening regions

    Science.gov (United States)

    Dilligan, Matthew Anthony

    Understanding the growth and arrest of cracks in composite materials is critical for their effective utilization in fatigue-sensitive and damage susceptible applications such as primary aircraft structures. Local tailoring of the laminate stack to provide crack arrest capacity intermediate to major structural components has been investigated and demonstrated since some of the earliest efforts in composite aerostructural design, but to date no rigorous model of the crack arrest mechanism has been developed to allow effective sizing of these features. To address this shortcoming, the previous work in the field is reviewed, with particular attention to the analysis methodologies proposed for similar arrest features. The damage and arrest processes active in such features are investigated, and various models of these processes are discussed and evaluated. Governing equations are derived based on a proposed mechanistic model of the crack arrest process. The derived governing equations are implemented in a numerical model, and a series of simulations are performed to ascertain the general characteristics of the proposed model and allow qualitative comparison to existing experimental results. The sensitivity of the model and the arrest process to various parameters is investigated, and preliminary conclusions regarding the optimal feature configuration are developed. To address deficiencies in the available material and experimental data, a series of coupon tests are developed and conducted covering a range of arrest zone configurations. Test results are discussed and analyzed, with a particular focus on identification of the proposed failure and arrest mechanisms. Utilizing the experimentally derived material properties, the tests are reproduced with both the developed numerical tool as well as a FEA-based implementation of the arrest model. Correlation between the simulated and experimental results is analyzed, and future avenues of investigation are identified

  4. Varanoid Tooth Eruption and Implantation Modes in a Late Cretaceous Mosasaur

    Directory of Open Access Journals (Sweden)

    Min eLiu

    2016-05-01

    Full Text Available Erupting teeth are some of the oldest witnesses of developmental processes in the vertebrate fossil record and provide an important resource for vertebrate cladistics. Here we have examined a mosasaur jaw fragment from central Texas using ultrathin ground section histology and 3D tomographic imaging to assess features critical for the cladistic placement of mosasaurs among varanoids versus snakes: (i the orientation of replacement teeth compared to the major tooth axis, (ii the occurrence of resorption pits, and (iii the mode of tooth implantation/attachment to the tooth bearing element. The replacement tooth studied here developed in an inclined position slightly distal of the deciduous parent tooth, similar to another varanoid squamate, the Gila monster Heloderma suspectum. Ground sections and tomographs also demonstrated that the replacement tooth attachment apparatus was entirely intact and that there was no evidence of mechanical deformation. Sections and tomographs further illustrated that the replacement tooth was located within a bony crypt and the inclination of the crypt matched the inclination of the replacement tooth. These preparations also revealed the presence of a resorption pit within the boundaries of the deciduous tooth that surrounded the developing replacement tooth. This finding suggests that developing mosasaur teeth developed within the walls of resorption pits similar to varanoid tooth germs and unlike developing snake teeth which are surrounded by fibrous connective tissue integuments. Finally, mosasaurs featured pseudo-thecodont tooth implantation with teeth anchored within a socket of mineralized tissue by means of a mineralized periodontal ligament. Together, these data indicate that the moderate inclination of the erupting mosasaur tooth studied here is neither a result of postmortem displacement nor a character representative of snakes, but rather a shared character between Mosasaurs and other varanoids such as

  5. Varanoid Tooth Eruption and Implantation Modes in a Late Cretaceous Mosasaur

    Science.gov (United States)

    Liu, Min; Reed, David A.; Cecchini, Giancarlo M.; Lu, Xuanyu; Ganjawalla, Karan; Gonzales, Carol S.; Monahan, Richard; Luan, Xianghong

    2016-01-01

    Erupting teeth are some of the oldest witnesses of developmental processes in the vertebrate fossil record and provide an important resource for vertebrate cladistics. Here, we have examined a mosasaur jaw fragment from central Texas using ultrathin ground section histology and 3D tomographic imaging to assess features critical for the cladistic placement of mosasaurs among varanoids vs. snakes: (i) the orientation of replacement teeth compared to the major tooth axis, (ii) the occurrence of resorption pits, and (iii) the mode of tooth implantation/attachment to the tooth bearing element (TBE). The replacement tooth studied here developed in an inclined position slightly distal of the deciduous parent tooth, similar to another varanoid squamate, the Gila monster Heloderma suspectum. Ground sections and tomographs also demonstrated that the replacement tooth attachment apparatus was entirely intact and that there was no evidence of mechanical deformation. Sections and tomographs further illustrated that the replacement tooth was located within a bony crypt and the inclination of the crypt matched the inclination of the replacement tooth. These preparations also revealed the presence of a resorption pit within the boundaries of the deciduous tooth that surrounded the developing replacement tooth. This finding suggests that developing mosasaur teeth developed within the walls of resorption pits similar to varanoid tooth germs and unlike developing snake teeth which are surrounded by fibrous connective tissue integuments. Finally, mosasaurs featured pseudo-thecodont tooth implantation with teeth anchored within a socket of mineralized tissue by means of a mineralized periodontal ligament. Together, these data indicate that the moderate inclination of the erupting mosasaur tooth studied here is neither a result of postmortem displacement nor a character representative of snakes, but rather a shared character between Mosasaurs and other varanoids such as Heloderma. In

  6. Global arrest of translation during invertebrate quiescence.

    OpenAIRE

    Hofmann, G E; Hand, S C

    1994-01-01

    Comparing the translational capacities of cell-free systems from aerobically developing embryos of the brine shrimp Artemia franciscana vs. quiescent embryos has revealed a global arrest of protein synthesis. Incorporation rates of [3H]leucine by lysates from 4-h anoxic embryos were 8% of those from aerobic (control) embryos, when assayed at the respective pH values measured for each treatment in vivo. Exposure of embryos to 4 h of aerobic acidosis (elevated CO2 in the presence of oxygen) sup...

  7. Fluoridation and tooth wear in Irish adults.

    LENUS (Irish Health Repository)

    Burke, F M

    2010-10-01

    The aim of this study was to determine the prevalence of tooth wear in adults in Ireland and its relationship with water fluoridation. The National Survey of Adult Oral Health was conducted in 2000\\/2001. Tooth wear was determined using a partial mouth examination assessing the upper and lower anterior teeth. A total of 2456 subjects were examined. In this survey, increasing levels and severity of tooth wear were associated with ageing. Men were more affected by tooth wear and were more likely to be affected by severe tooth wear than women. It was found that age, and gender were significant predictors of tooth wear (P < 0.01). Overall, there was no significant relationship between fluoridation and tooth wear in this study.

  8. Proteomic Analysis of Human Tooth Pulp: Proteomics of Human Tooth

    Czech Academy of Sciences Publication Activity Database

    Eckhardt, Adam; Jágr, Michal; Pataridis, Statis; Mikšík, Ivan

    2014-01-01

    Roč. 40, č. 12 (2014), s. 1961-1966. ISSN 0099-2399 R&D Projects: GA ČR(CZ) GA13-17224S; GA ČR(CZ) GAP206/12/0453; GA MZd(CZ) NT14324 Institutional support: RVO:67985823 Keywords : dentin * human pulp * tandem mass spectrometry * tooth proteome * 2-dimensional gel electrophoresis Subject RIV: FF - HEENT, Dentistry Impact factor: 3.375, year: 2014

  9. Tooth extraction by orthodontic force after radiation therapy: report of case

    International Nuclear Information System (INIS)

    This report presents a therapeutic approach to orthodontic tooth extraction in a patient at high risk for the development of osteoradionecrosis with conventional techniques. The rationale for this procedure is discussed in detail, combining principles of radiation biology, clinical radiation therapy, and biomechanics of tooth movement

  10. pitx2基因早期过量表达对斑马鱼牙齿生长发育相关基因的影响%The effect of pitx2 over expression on the expression of the genes involved in tooth development in the early stage

    Institute of Scientific and Technical Information of China (English)

    陆琼琼; 王娟; 赵庆顺; 李谨

    2013-01-01

    AIM: To study the effect of pitx2 over expression on the expression of the genes involved in tooth development in the early stage. METHODS: Specific gene fragment of pitx2 gene was cloned and the restriction enzyme cutting site in the two terminals was inserted. Pitx2 mRNA was synthesized by reverse transcription -polymerase chain reaction( RT-PCR) using the pitx2 coding sequence( CDS) as the template. 100 zebrafish embryos (0h) were used in each of the following groupes; in groupe Ⅰ pitx2 mRNA at 200 pg/nL was microinjected into a zebrafish embryo and in group Ⅱ at 100pg/nL; in group Ⅲ100 pg/nL yellow fluorescent protein ( YFP) mRNA was given as the control and in group Ⅳ the natural mating was served as the wild type control. The development of the zebrafish embryos was observed for 72 h. Bmp4 , fgf8 , dlx2b , runx2a and left expressions of the embryos in the 4 groups were examined at 24 h,48 h and 72 h respectively after microinjection by semi-quantitative RT-PCR and grayscale value analysis. RESULTS: pitx2 mRNA was synthesized and identified. In group Ⅰ 66% embryos died in 24h after microinjection , the development of the rest zebrafish embryos was arrested or in dysgenesis. The survival ratios of the other 3 groupes were 84% or more. In groupe fl development arrest, pericardial edema, spinal deformity and eye malformations were observed in 72 h; bmp4 expression was down regulated, fgf8 , lef1 and runx2a expressions were up regulated , dlx2b expression was not changed. CONCLUSION: pitx2 over expression may impact the expression of the genes involved in tooth development in the early stage.%目的:研究pitx2基因早期过量表达对斑马鱼牙齿发育相关基因的影响.方法:利用RT-PCR技术克隆pitx2特异性基因片段;插入特异性酶切位点后以之为模板体外合成pitx2 mRNA.选取正常交配获得的斑马鱼胚胎,随机分为4组采用显微注射技术构建pitx2过表达模型:实验1组注射pitx2 mRNA200 pg

  11. Multiple essential MT1-MMP functions in tooth root formation, dentinogenesis, and tooth eruption.

    Science.gov (United States)

    Xu, H; Snider, T N; Wimer, H F; Yamada, S S; Yang, T; Holmbeck, K; Foster, B L

    2016-01-01

    Membrane-type matrix metalloproteinase 1 (MT1-MMP) is a transmembrane zinc-endopeptidase that breaks down extracellular matrix components, including several collagens, during tissue development and physiological remodeling. MT1-MMP-deficient mice (MT1-MMP(-/-)) feature severe defects in connective tissues, such as impaired growth, osteopenia, fibrosis, and conspicuous loss of molar tooth eruption and root formation. In order to define the functions of MT1-MMP during root formation and tooth eruption, we analyzed the development of teeth and surrounding tissues in the absence of MT1-MMP. In situ hybridization showed that MT1-MMP was widely expressed in cells associated with teeth and surrounding connective tissues during development. Multiple defects in dentoalveolar tissues were associated with loss of MT1-MMP. Root formation was inhibited by defective structure and function of Hertwig's epithelial root sheath (HERS). However, no defect was found in creation of the eruption pathway, suggesting that tooth eruption was hampered by lack of alveolar bone modeling/remodeling coincident with reduced periodontal ligament (PDL) formation and integration with the alveolar bone. Additionally, we identified a significant defect in dentin formation and mineralization associated with the loss of MT1-MMP. To segregate these multiple defects and trace their cellular origin, conditional ablation of MT1-MMP was performed in epithelia and mesenchyme. Mice featuring selective loss of MT1-MMP activity in the epithelium were indistinguishable from wild type mice, and importantly, featured a normal HERS structure and molar eruption. In contrast, selective knock-out of MT1-MMP in Osterix-expressing mesenchymal cells, including osteoblasts and odontoblasts, recapitulated major defects from the global knock-out including altered HERS structure, short roots, defective dentin formation and mineralization, and reduced alveolar bone formation, although molars were able to erupt. These data

  12. Changing the guard: Polymer replaces porcelain for surge arresters

    Energy Technology Data Exchange (ETDEWEB)

    Skytt, T.; Gleimar, H. E. G.

    2002-07-01

    Surge arresters are safety devices which quickly and effectively limit the over voltages that can arise in transmission networks following lightning, switching and other transient events. The earliest forms of overvoltage protection, a simple air gap between electrodes, have long since been replaced by a new generation of gapless arresters with series-connected, non-linear zinc oxide varistors contained in a porcelain housing. Now these porcelain type surge arresters are being replaced by a new type, called PEXLIM (Polymeric EXcellent LIMiter), which uses the same block of zinc oxide as the porcelain type, but its housing is made of silicon rubber, a polymer. The new lightweight insulation material shows a number of properties superior to the porcelain, such as enhanced product safety and ease of handling. It is also more durable, resilient, yet solid and compact, water-repellent, lightweight, resistant to aging or light or ultra-violet radiation, as well as fire, has good electrical properties, and is environmentally friendly since it does not contain any substances harmful to the environment. These properties make this new type of surge arrester highly suitable for use in earthquake-prone areas; it can also replace more expensive and maintenance-intensive equipment. Having successfully broken into the lower voltage systems, these new type of surge arresters are now rapidly gaining ground at the higher voltage levels. ABB, the developer of PEXLIM, has already supplied these arresters to North America for use in an 800-kV grid. As further proof of its growing popularity, last year PEXLIM made up over half of the surge arrester production for applications up to and including 245 kV. 1 tab., 6 figs.

  13. Optical spectroscopy and tooth decay

    Science.gov (United States)

    Misra, P.; De, T.; Singh, R.

    2005-11-01

    Optical spectroscopy in the ultraviolet, visible and mid-infrared spectral regions has been used to discriminate between healthy and diseased teeth of patients in the age range 15-75 years. Spectral scans of absorbance versus wavenumber and fluorescence intensity versus wavelength have been recorded and investigated for caries and periodontal disease. Such optical diagnostics can prove very useful in the early detection and treatment of tooth decay.

  14. Charcot-Marie-Tooth disease.

    LENUS (Irish Health Repository)

    Reilly, Mary M

    2011-03-01

    Charcot-Marie-Tooth (CMT) disease is the commonest inherited neuromuscular disorder affecting at least 1 in 2,500. Over the last two decades, there have been rapid advances in understanding the molecular basis for many forms of CMT with more than 30 causative genes now described. This has made obtaining an accurate genetic diagnosis possible but at times challenging for clinicians. This review aims to provide a simple, pragmatic approach to diagnosing CMT from a clinician\\'s perspective.

  15. Mechanical modelling of tooth wear.

    Science.gov (United States)

    Karme, Aleksis; Rannikko, Janina; Kallonen, Aki; Clauss, Marcus; Fortelius, Mikael

    2016-07-01

    Different diets wear teeth in different ways and generate distinguishable wear and microwear patterns that have long been the basis of palaeodiet reconstructions. Little experimental research has been performed to study them together. Here, we show that an artificial mechanical masticator, a chewing machine, occluding real horse teeth in continuous simulated chewing (of 100 000 chewing cycles) is capable of replicating microscopic wear features and gross wear on teeth that resemble wear in specimens collected from nature. Simulating pure attrition (chewing without food) and four plant material diets of different abrasives content (at n = 5 tooth pairs per group), we detected differences in microscopic wear features by stereomicroscopy of the chewing surface in the number and quality of pits and scratches that were not always as expected. Using computed tomography scanning in one tooth per diet, absolute wear was quantified as the mean height change after the simulated chewing. Absolute wear increased with diet abrasiveness, originating from phytoliths and grit. In combination, our findings highlight that differences in actual dental tissue loss can occur at similar microwear patterns, cautioning against a direct transformation of microwear results into predictions about diet or tooth wear rate. PMID:27411727

  16. Global arrest of translation during invertebrate quiescence.

    Science.gov (United States)

    Hofmann, G E; Hand, S C

    1994-08-30

    Comparing the translational capacities of cell-free systems from aerobically developing embryos of the brine shrimp Artemia franciscana vs. quiescent embryos has revealed a global arrest of protein synthesis. Incorporation rates of [3H]leucine by lysates from 4-h anoxic embryos were 8% of those from aerobic (control) embryos, when assayed at the respective pH values measured for each treatment in vivo. Exposure of embryos to 4 h of aerobic acidosis (elevated CO2 in the presence of oxygen) suppressed protein synthesis to 3% of control values. These latter two experimental treatments promote developmental arrest of Artemia embryos and, concomitantly, cause acute declines in intracellular pH. When lysates from each treatment were assayed over a range of physiologically relevant pH values (pH 6.4-8.0), amino acid incorporation rates in lysates from quiescent embryos were consistently lower than values for the aerobic controls. Acute reversal of pH to alkaline values during the 6-min assays was not sufficient to return the incorporation rates of quiescent lysates to control values. Thus, a stable alteration in translational capacity of quiescent lysates is indicated. Addition of exogenous mRNA did not rescue the suppressed protein synthesis in quiescent lysates, which suggests that the acute blockage of amino acid incorporation is apparently not due to limitation in message. Thus, the results support a role for intracellular pH as an initial signaling event in translational control during quiescence yet, at the same time, indicate that a direct proton effect on the translational machinery is not the sole proximal agent for biosynthetic arrest in this primitive crustacean. PMID:8078909

  17. Mesenchymal Stem Cells and Tooth Engineering

    Institute of Scientific and Technical Information of China (English)

    Li Peng; Ling Ye; Xue-dong Zhou

    2009-01-01

    Tooth loss compromises human oral health. Although several prosthetic methods, such as artificial denture and dental implants, are clinical therapies to tooth loss problems, they are thought to have safety and usage time issues. Recently, tooth tissue engineering has attracted more and more attention. Stem cell based tissue engineering is thought to be a promising way to replace the missing tooth. Mesenchymal stem cells (MSCs) are multipotent stem cells which can differentiate into a variety of cell types. The potential MSCs for tooth regeneration mainly include stem cells from human exfoliated deciduous teeth (SHEDs), adult dental pulp stem cells (DPSCs), stem cells from the apical part of the papilla (SCAPs), stem cells from the dental follicle (DFSCs), periodontal ligament stem cells (PDLSCs) and bone marrow derived mesenchymal stem cells (BMSCs). This review outlines the recent progress in the mesenchymal stem cells used in tooth regeneration.

  18. Visualization of Tooth for Non-Destructive Evaluation from CT Images

    International Nuclear Information System (INIS)

    This paper reports an effort to develop 3D tooth visualization system from CT sequence images as a part of the non-destructive evaluation suitable for the simulation of endodontics, orthodontics and other dental treatments. We focus on the segmentation and visualization for the individual tooth. In dental CT images teeth are touching the adjacent teeth or surrounded by the alveolar bones with similar intensity. We propose an improved level set method with shape prior to separate a tooth from other teeth as well as the alveolar bones. Reconstructed 3D model of individual tooth based on the segmentation results indicates that our technique is a very conducive tool for tooth visualization, evaluation and diagnosis. Some comparative visualization results validate the non-destructive function of our method.

  19. Visualization of Tooth for Non-Destructive Evaluation from CT Images

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Hui; Chae, Ok Sam [Kyung Hee University, Seoul (Korea, Republic of)

    2009-06-15

    This paper reports an effort to develop 3D tooth visualization system from CT sequence images as a part of the non-destructive evaluation suitable for the simulation of endodontics, orthodontics and other dental treatments. We focus on the segmentation and visualization for the individual tooth. In dental CT images teeth are touching the adjacent teeth or surrounded by the alveolar bones with similar intensity. We propose an improved level set method with shape prior to separate a tooth from other teeth as well as the alveolar bones. Reconstructed 3D model of individual tooth based on the segmentation results indicates that our technique is a very conducive tool for tooth visualization, evaluation and diagnosis. Some comparative visualization results validate the non-destructive function of our method.

  20. Cognitive and Functional Consequence of Cardiac Arrest.

    Science.gov (United States)

    Perez, Claudia A; Samudra, Niyatee; Aiyagari, Venkatesh

    2016-08-01

    Cardiac arrest is associated with high morbidity and mortality. Better-quality bystander cardiopulmonary resuscitation training, cardiocerebral resuscitation principles, and intensive post-resuscitation hospital care have improved survival. However, cognitive and functional impairment after cardiac arrest remain areas of concern. Research focus has shifted beyond prognostication in the immediate post-arrest period to identification of mechanisms for long-term brain injury and implementation of promising protocols to reduce neuronal injury. These include therapeutic temperature management (TTM), as well as pharmacologic and psychological interventions which also improve overall neurological function. Comprehensive assessment of cognitive function post-arrest is hampered by heterogeneous measures among studies. However, the domains of attention, long-term memory, spatial memory, and executive function appear to be affected. As more patients survive cardiac arrest for longer periods of time, there needs to be a greater focus on interventions that can enhance cognitive and psychosocial function post-arrest. PMID:27311306

  1. Tooth use in Aboriginal Australia

    Directory of Open Access Journals (Sweden)

    Anna Clement

    2008-09-01

    Full Text Available The study of dental casts taken from living people avoids the ethical problems of research into human remains, while providing valuable information about diet and life styles. This article describes a study of tooth wear in dental casts of three different groups of Australian Aborigines. The authors describe their methods of recording and report differential patterns of wear in the different groups. Preliminary interpretation relates the wear patterns both to diet and to the use of teeth as tools in a range of cultural activities, results which are potentially relevant to other groups of hunter-gatherers, past and present.

  2. Micro-PIXE (proton-induced X-ray emission) study of the effects of fluoride on mineral distribution patterns in enamel and dentin in the developing hamster tooth germ

    International Nuclear Information System (INIS)

    Micro-PIXE (proton-induced X-ray emission) analysis was performed on unfixed and anhydrously prepared sections from developing enamel and dentin from hamsters injected with a single dose of 20 mg NaF/kg body weight. Fluoride, apart from inducing the formation of the characteristic paired response in the enamel (i.e., a hyper- followed by a hypomineralized band in the secretory enamel), also induces the formation of sub-ameloblastic cystic lesions under the transitional and early secretory enamel accompanied by relatively intense hypermineralization of the underlying cystic enamel surface. These cystic lesions, however, were only found to be associated with certain isolated populations of these cells. In addition, these lesions were restricted to the smooth surfaces of the tooth germ only. Cystic lesions such as those seen under the transitional and early secretory ameloblasts were not observed under the fully secretory or maturation stage ameloblasts. Why fluoride induces the formation of cystic lesions in some ameloblast populations while other cells in the same stage of development apparently remain unaffected, is a matter which needs further investigation

  3. Removal of deciduous canine tooth buds in Kenyan rural Maasai.

    Science.gov (United States)

    Hassanali, J; Amwayi, P; Muriithi, A

    1995-04-01

    The removal of deciduous canine tooth buds in early childhood is a practice that has been documented in Kenya and in neighboring countries. This paper describes the occurrence, rationale and method of this practice amongst rural Kenyan Maasai. In a group of 95 children aged between six months and two years, who were examined in 1991/92, 87% were found to have undergone the removal of one or more deciduous canine tooth buds. In an older age group (3-7 years of age), 72% of the 111 children examined exhibited missing mandibular or maxillary deciduous canines. It was found that the actual removal of a deciduous tooth bud is often performed by middle-aged Maasai women who enucleate the developing tooth using a pointed pen-knife. There exists a strong belief among the Maasai that diarrhoea, vomiting and other febrile illnesses of early childhood are caused by the gingival swelling over the canine region, and which is thought to contain 'worms' or 'nylon' teeth. The immediate and long-term hazards of this practice include profuse bleeding, infection and damage to the developing permanent canines. A multi-disciplinary approach involving social anthropologists in addition to dental and medical personnel, is recommend in order to discourage this harmful operation that appears to be on the increase. PMID:7621751

  4. Simulated Cardiopulmonary Arrests in a Hospital Setting.

    Science.gov (United States)

    Mishkin, Barbara H.; And Others

    1982-01-01

    Describes a simulated interdisciplinary role rehearsal for cardiopulmonary arrest to prepare nurses to function effectively. Includes needs analysis, program components, and responses of program participants. (Author)

  5. [Out-of-hospital cardiac arrest].

    Science.gov (United States)

    Virkkunen, Ilkka; Hoppu, Sanna; Kämäräinen, Antti

    2011-01-01

    Cardiac arrest as the first symptom of coronary artery disease is not uncommon. Some of previously healthy people with sudden cardiac arrest may be saved by effective resuscitation and post-resuscitative therapy. The majority of cardiac arrest patients experience the cardiac arrest outside of the hospital, in which case early recognition of lifelessness, commencement of basic life support and entry to professional care without delay are the prerequisites for recovery. After the heart has started beating again, the clinical picture of post-resuscitation syndrome must be recognized and appropriate treatment utilized. PMID:22204143

  6. Police Management Training Factors Influencing DWI Arrests. Final Report.

    Science.gov (United States)

    Bishop, Edward W.

    The development of training material for police management personnel concerning command and supervisory actions appropriate for more effective driving-while-intoxicated (DWI) enforcement is desired. The training is based on two research studies that identified environmental and attitudinal factors influencing a patrolman's arrest decision. These…

  7. Anaphylactic shock and cardiac arrest caused by thiamine infusion

    DEFF Research Database (Denmark)

    Juel, Jacob; Pareek, Manan; Langfrits, Christian Sigvald;

    2013-01-01

    intoxication and developed cardiac arrest due to anaphylactic shock following intravenous thiamine infusion. The patient was successfully resuscitated after 15 min and repeated epinephrine administrations. He was discharged in good health after 14 days. This case report emphasises both the importance...

  8. Intense ultrasonic clicks from echolocating toothed whales do not elicit anti-predator responses or debilitate the squid Loligo pealeii

    OpenAIRE

    Wilson, Maria; Hanlon, Roger T.; Tyack, Peter L; Madsen, Peter T.

    2007-01-01

    Toothed whales use intense ultrasonic clicks to echolocate prey and it has been hypothesized that they also acoustically debilitate their prey with these intense sound pulses to facilitate capture. Cephalopods are an important food source for toothed whales, and there has probably been an evolutionary selection pressure on cephalopods to develop a mechanism for detecting and evading sound-emitting toothed whale predators. Ultrasonic detection has evolved in some insects to avoid echolocating ...

  9. Swedish ambulance nurses' experiences of nursing patients suffering cardiac arrest.

    Science.gov (United States)

    Larsson, Ricard; Engström, Åsa

    2013-04-01

    Effective pre-hospital treatment of a person suffering cardiac arrest is a challenging task for the ambulance nurses. The aim of this study was to describe ambulance nurses' experiences of nursing patients suffering cardiac arrest. Qualitative personal interviews were conducted during 2011 in Sweden with seven ambulance nurses with experience of nursing patients suffering cardiac arrests. The interview texts were analyzed using qualitative thematic content analysis, which resulted in the formulation of one theme with six categories. Mutual preparation, regular training and education were important factors in the nursing of patients suffering cardiac arrest. Ambulance nurses are placed in ethically demanding situations regarding if and for how long they should continue cardio-pulmonary resuscitation (CPR) to accord with pre-hospital cardiac guidelines and patients' wishes. When a cardiac arrest patient is nursed their relatives also need the attention of ambulance nurses. Reflection is one way for ambulance nurses to learn from, and talk about, their experiences. This study provides knowledge of ambulance nurses' experiences in the care of people with cardiac arrest. Better feedback about the care given by the ambulance nurses, and about the diagnosis and nursing care the patients received after they were admitted to the hospital are suggested as improvements that would allow ambulance nurses to learn more from their experience. Further development and research concerning the technical equipment might improve the situation for both the ambulance nurses and the patients. Ambulance nurses need regularly training and education to be prepared for saving people's lives and also to be able to make the right decisions. PMID:23577977

  10. TLR signalling can modify the mineralization of tooth germ.

    Science.gov (United States)

    Papp, Tamas; Hollo, Krisztina; Meszar-Katona, Eva; Nagy, Zoltan; Polyak, Angela; Miko, Edit; Bai, Peter; Felszeghy, Szabolcs

    2016-05-01

    Objective The aim of this work is to investigate the possible role of Toll-like receptor 4 (TLR4) during the development of mouse tooth germ. TLR4 is well known to inhibit mineralization and cause inflammation in mature odontoblasts and dental pulp cells. However, unlike these pathological functions of TLR4, little is known about the developmental function(s) of TLR4 during tooth development. Materials and methods TLR4 expression was studied via Western blot in developing lower mouse incisors from E13.5 to E18.5. To generate functional data about the effects of TLR4, a specific agonist (LPS) was applied to the medium of in vitro tooth germ cultures, followed by Western blot, histochemical staining, ELISA assay, in situ hybridization and RT-qPCR. Results Increased accumulation of biotin-labelled LPS was detected in the enamel organ and in preodontoblasts. LPS treatment induced degradation of the inhibitor molecule (IκB) of the NF-κB signalling pathway. However, no morphological alterations were detected in cultured tissue after LPS addition at the applied dosage. Activation of TLR4 inhibited the mineralization of enamel and dentin, as demonstrated by alizarin red staining and as decreased levels of collagen type X. mRNA expression of ameloblastin was elevated after LPS administration. Conclusion These results demonstrate that TLR4 may decrease the mineralization of hard tissues of the tooth germ and may trigger the maturation of ameloblasts; it can give valuable information to understand better congenital tooth abnormalities. PMID:26763602

  11. DIET EFFECT ON TOOTH DECAY WITH INDEX KPE EVALUATION IN BLANSKO

    OpenAIRE

    Vašíčková, Pavlína

    2009-01-01

    Regular development of our teeth is the result of reciprocal induction processes with continual development stages. The non-interrupted development of the organism is the basic precondition of healthy dental tissues. It is, therefore, necessary to be aware of the fact that everybody takes on full responsibility for their own health. If we want to have clean and healthy teeth without tooth ache, oulitis and other problems we must take proper dental care. Tooth decay is the most widespread dise...

  12. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Disorder What is Baby Bottle Tooth Decay? Men: Looking for a Better Job? Start by Visiting the Dentist When Should My Child First See a Dentist? Learn what those dental words mean. The Life of a Tooth games Home | InfoBites | Find a Dentist | Your Family's Oral Health | ...

  13. Addressing Tooth Decay in Head Start Children

    Science.gov (United States)

    Knowlden, Adam P.; Hill, Lawrence F.; Alles-White, Monica L.; Cottrell, Randall R.

    2012-01-01

    Tooth decay is the most prevalent chronic disease of childhood. Oral health education and dental services are crucial to reducing the number of children afflicted with dental cavities. Due to limited access to preventative care, Head Start children are particularly vulnerable to tooth decay. This article outlines practical implications of a…

  14. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Quick Reference Learn more Nutrition - Adults What is Dental Amalgam (Silver Filling)? Are You Biting Off More Than You Can Chew? What is Baby Bottle Tooth Decay? Men: Looking for a Better Job? Start by Visiting the Dentist Is My Child at Risk for Early Childhood ... The Life of a Tooth games ...

  15. Life of a Tooth: A Visual Timeline

    Science.gov (United States)

    ... Quick Reference Learn more Nutrition - Adults What is Dental Amalgam (Silver Filling)? Are You Biting Off More Than You Can Chew? What is Baby Bottle Tooth Decay? Men: Looking for a Better Job? Start by Visiting the Dentist Is My Child at Risk for Early Childhood ... The Life of a Tooth games ...

  16. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Decay? Check Menstrual Calendar for Tooth Extraction The History of Dental Advances Men: Looking for a Better Job? Start by Visiting the Dentist Learn what those dental words mean. The Life of a Tooth games Home | InfoBites | Find a ...

  17. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health What is Baby Bottle Tooth Decay? Is My ... for Early Childhood Tooth Decay? Why is Oral Health Important for Men? When Should My Child First ...

  18. Pinion tooth surface generation strategy of spiral bevel gears

    Science.gov (United States)

    Liu, Guanglei; Fan, Hongwei

    2012-07-01

    Aviation spiral bevel gears are often generated by spiral generated modified (SGM) roll method. In this style, pinion tooth surface modified generation strategy has an important influence on the meshing and contact performances. For the optimal contact pattern and transmission error function, local synthesis is applied to obtain the machine-tool settings of pinion. For digitized machine, four tooth surface generation styles of pinion are proposed. For every style, tooth contact analysis (TCA) is applied to obtain contact pattern and transmission error function. For the difference between TCA transmission error function and design objective curve, the degree of symmetry and agreement are defined and the corresponding sub-objective functions are established. Linear weighted combination method is applied to get an equivalent objective function to evaluate the shape of transmission error function. The computer programs for the process above are developed to analyze the meshing performances of the four pinion tooth surface generation styles for a pair of aviation spiral bevel gears with 38/43 teeth numbers. The four analytical results are compared with each other and show that the incomplete modified roll is optimal for this gear pair. This study is an expansion to generation strategy of spiral bevel gears, and offers new alternatives to computer numerical control (CNC) manufacture of spiral bevel gears.

  19. Buoyant currents arrested by convective dissolution

    Science.gov (United States)

    MacMinn, Christopher W.; Juanes, Ruben

    2013-05-01

    When carbon dioxide (CO2) dissolves into water, the density of water increases. This seemingly insubstantial phenomenon has profound implications for geologic carbon sequestration. Here we show, by means of laboratory experiments with analog fluids, that the up-slope migration of a buoyant current of CO2 is arrested by the convective dissolution that ensues from a fingering instability at the moving CO2-groundwater interface. We consider the effectiveness of convective dissolution as a large-scale trapping mechanism in sloping aquifers, and we show that a small amount of slope is beneficial compared to the horizontal case. We study the development and coarsening of the fingering instability along the migrating current and predict the maximum migration distance of the current with a simple sharp-interface model. We show that convective dissolution exerts a powerful control on CO2 plume dynamics and, as a result, on the potential of geologic carbon sequestration.

  20. Retinoid receptor-specific agonists regulate bovine in vitro early embryonic development, differentiation and expression of genes related to cell cycle arrest and apoptosis.

    Science.gov (United States)

    Rodríguez, A; Díez, C; Caamaño, J N; de Frutos, C; Royo, L J; Muñoz, M; Ikeda, S; Facal, N; Alvarez-Viejo, M; Gómez, E

    2007-11-01

    A major goal in reproductive biotechnology is the identification of pathways that regulate early embryonic development and the allocation of cells to the inner cell mass (ICM) and trophectoderm (TE). Retinoids regulate the development and differentiation of the bovine blastocyst in vitro, although the involvement of the retinoid X receptors (RXRs) remains to be clarified. This paper compares the effect of a synthetic RXR agonist (LG100268; LG) with that of the retinoic acid receptor (RAR) agonist all-trans retinoic acid (ATRA) on blastulation. In vitro-produced morulae were treated for 48 h with LG (0.1 microM, 1 microM and 10 microM), ATRA 0.7 microM, or no additives. Treatment with ATRA did not increase the rate of development; however, the LG 0.1 microM treatment increased both the blastocyst development and hatching rate. Cell numbers increased in the ICM with LG 10 microM, while a dose-dependent reduction was observed in the TE in the presence of LG. Gene expression levels of p53 and p66 did not vary with LG but increased with ATRA. Both LG and ATRA activated bax, a pro-apoptotic gene and H2A.Z, a cell cycle-related gene. The above effects suggest the existence of active p53-dependent and -independent apoptotic pathways for ATRA and LG, respectively, in the bovine embryo. The expression of p53 and H2A.Z showed a strong, positive correlation (r=0.93; pdevelopment and differentiation. PMID:17869331

  1. Psychopathology in Women Arrested for Domestic Violence

    Science.gov (United States)

    Stuart, Gregory L.; Moore, Todd M.; Gordon, Kristina Coop; Ramsey, Susan E.; Kahler, Christopher W.

    2006-01-01

    This study examined the prevalence of psychopathology among women arrested for violence and whether the experience of intimate partner violence (IPV) was associated with Axis I psychopathology. Women who were arrested for domestic violence perpetration and court referred to violence intervention programs (N=103) completed measures of IPV…

  2. The course of circulatory and cerebral recovery after circulatory arrest: influence of pre-arrest, arrest and post-arrest factors.

    Science.gov (United States)

    Jørgensen, E O; Holm, S

    1999-11-01

    We evaluated the influence of pre-arrest, arrest and post-arrest factors on circulatory and neurological recovery for up to 1 year following circulatory arrest of cardio-pulmonary aetiology in 231 patients. Initially, all patients were unconscious and 106 had some cortical activity recorded in the immediate post-resuscitation EEG (Group I), while 125 had no such activity initially (Group II). The following variables were explored: age, sex, medical history, cause and location of arrest, initial cardiac dysrhythmia, duration of life support, metabolic acidosis, pulse-pressure product and heart pump function capacity early after resuscitation. Outcome measures were duration and quality of circulatory survival, cause of death, neurological recovery and ultimate outcome. First year survival was 33% in Group I and 16% in Group II. Severe heart failure and brain death occurred mainly in Group II. Circulatory recovery was negatively influenced by out-of-hospital arrest, metabolic acidosis and pulse-pressure products below 150. Neurological recovery was negatively influenced by initial dysrhythmias other than ventricular fibrillation, pulse-pressure products below 150, post-arrest heart failure and/or pulmonary complications. It seems that circulatory and cerebral outcomes are mainly determined by the global ischaemic insults sustained during the circulatory arrest period. PMID:10625157

  3. Arrest of metamorphosis induced by x rays in flesh fly, Sarcophaga peregrina

    International Nuclear Information System (INIS)

    Arrest of metamorphosis induced by x irradiation at prepupal stage was studied histologically, and age dependency of radiosensitivity with regard to this effect was examined. Prepupae did not cease their development soon after irradiation, but continued to develop and evaginated the head and the thorax. At this point, development came to a stop. In these animals, not only the histogenesis of imaginal tissues but also the histolysis of larval tissues was arrested. Since the arrest of development was not observed after irradiation at the pupal stage, the effect was considered to result from inhibition of initiation of postpupation development. A possible mechanism of the arrest of postpupation development in the irradiated animals was discussed in connection with the neuroendocrine control of insect development

  4. Prosthetic clone and natural human tooth comparison by speckle interferometry

    Science.gov (United States)

    Slangen, Pierre; Corn, Stephane; Fages, Michel; Raynal, Jacques; Cuisinier, Frederic J. G.

    2010-09-01

    New trends in dental prosthodontic interventions tend to preserve the maximum of "body" structure. With the evolution of CAD-CAM techniques, it is now possible to measure "in mouth" the remaining dental tissues. The prosthetic crown is then designed using this shape on which it will be glued on, and also by taking into account the contact surface of the opposite jaw tooth. Several theories discuss on the glue thickness and formulation, but also on the way to evolve to a more biocompatible crown and also new biomechanical concepts. In order to validate these new concepts and materials, and to study the mechanical properties and mechanical integrity of the prosthesis, high resolution optical measurements of the deformations of the glue and the crown are needed. Samples are two intact premolars extracted for orthodontics reasons. The reference sample has no modifications on the tooth while the second sample tooth is shaped to receive a feldspathic ceramic monoblock crown which will be glued. This crown was manufactured with a chairside CAD-CAM system from an intra-oral optical print. The software allows to realize a nearly perfect clone of the reference sample. The necessary space for the glue is also entered with ideal values. This duplication process yields to obtain two samples with identical anatomy for further processing. The glue joint thickness can also be modified if required. The purpose is to compare the behaviour of a natural tooth and its prosthetic clone manufactured with "biomechanical" concepts. Vertical cut samples have been used to deal with planar object observation, and also to look "inside" the tooth. We have developed a complete apparatus enabling the study of the compressive mechanical behaviour of the concerned tooth by speckle interferometry. Because in plane displacements are of great interest for orthodontic measurements1, an optical fiber in-plane sensitive interferometer has been designed. The fibers are wrapped around piezoelectric

  5. Benzyl Isothiocyanate Inhibits Prostate Cancer Development in the Transgenic Adenocarcinoma Mouse Prostate (TRAMP) Model, Which Is Associated with the Induction of Cell Cycle G1 Arrest.

    Science.gov (United States)

    Cho, Han Jin; Lim, Do Young; Kwon, Gyoo Taik; Kim, Ji Hee; Huang, Zunnan; Song, Hyerim; Oh, Yoon Sin; Kang, Young-Hee; Lee, Ki Won; Dong, Zigang; Park, Jung Han Yoon

    2016-01-01

    Benzyl isothiocyanate (BITC) is a hydrolysis product of glucotropaeolin, a compound found in cruciferous vegetables, and has been shown to have anti-tumor properties. In the present study, we investigated whether BITC inhibits the development of prostate cancer in the transgenic adenocarcinoma mouse prostate (TRAMP) mice. Five-week old, male TRAMP mice and their nontransgenic littermates were gavage-fed with 0, 5, or 10 mg/kg of BITC every day for 19 weeks. The weight of the genitourinary tract increased markedly in TRAMP mice and this increase was suppressed significantly by BITC feeding. H and E staining of the dorsolateral lobes of the prostate demonstrated that well-differentiated carcinoma (WDC) was a predominant feature in the TRAMP mice. The number of lobes with WDC was reduced by BITC feeding while that of lobes with prostatic intraepithelial neoplasia was increased. BITC feeding reduced the number of cells expressing Ki67 (a proliferation marker), cyclin A, cyclin D1, and cyclin-dependent kinase (CDK)2 in the prostatic tissue. In vitro cell culture results revealed that BITC decreased DNA synthesis, as well as CDK2 and CDK4 activity in TRAMP-C2 mouse prostate cancer cells. These results indicate that inhibition of cell cycle progression contributes to the inhibition of prostate cancer development in TRAMP mice treated with BITC. PMID:26907265

  6. Benzyl Isothiocyanate Inhibits Prostate Cancer Development in the Transgenic Adenocarcinoma Mouse Prostate (TRAMP Model, Which Is Associated with the Induction of Cell Cycle G1 Arrest

    Directory of Open Access Journals (Sweden)

    Han Jin Cho

    2016-02-01

    Full Text Available Benzyl isothiocyanate (BITC is a hydrolysis product of glucotropaeolin, a compound found in cruciferous vegetables, and has been shown to have anti-tumor properties. In the present study, we investigated whether BITC inhibits the development of prostate cancer in the transgenic adenocarcinoma mouse prostate (TRAMP mice. Five-week old, male TRAMP mice and their nontransgenic littermates were gavage-fed with 0, 5, or 10 mg/kg of BITC every day for 19 weeks. The weight of the genitourinary tract increased markedly in TRAMP mice and this increase was suppressed significantly by BITC feeding. H and E staining of the dorsolateral lobes of the prostate demonstrated that well-differentiated carcinoma (WDC was a predominant feature in the TRAMP mice. The number of lobes with WDC was reduced by BITC feeding while that of lobes with prostatic intraepithelial neoplasia was increased. BITC feeding reduced the number of cells expressing Ki67 (a proliferation marker, cyclin A, cyclin D1, and cyclin-dependent kinase (CDK2 in the prostatic tissue. In vitro cell culture results revealed that BITC decreased DNA synthesis, as well as CDK2 and CDK4 activity in TRAMP-C2 mouse prostate cancer cells. These results indicate that inhibition of cell cycle progression contributes to the inhibition of prostate cancer development in TRAMP mice treated with BITC.

  7. Reducing Early Childhood Tooth Decay: Leading Steps for State Policymakers

    OpenAIRE

    Leslie Foster; Meg Booth; Colin Reusch

    2015-01-01

    Young children who are enrolled in Medicaid or the Children’s Health Insurance Program (CHIP) can be at risk for developing early childhood caries (ECC). ECC is a chronic bacterial infection that causes severe tooth decay and can begin to develop before baby teeth erupt. Children with ECC may experience pain, difficulty eating, developmental complications, and loss of days in day care or preschool. ECC is expensive to treat and untreated ECC can lead to other serious infections.

  8. Mechanism of human tooth eruption

    DEFF Research Database (Denmark)

    Kjær, Inger

    2014-01-01

    Human eruption is a unique developmental process in the organism. The aetiology or the mechanism behind eruption has never been fully understood and the scientific literature in the field is extremely sparse. Human and animal tissues provide different possibilities for eruption analyses, briefly......, and the ability of the periodontal ligament to adapt to eruptive movements. Animal studies and studies on normal and pathological eruption in humans can support and explain different aspects in the new theory. The eruption mechanism still needs elucidation and the paper recommends that future research...... discussed in the introduction. Human studies, mainly clinical and radiological, have focused on normal eruption and gender differences. Why a tooth begins eruption and what enables it to move eruptively and later to end these eruptive movements is not known. Pathological eruption courses contribute to...

  9. Dental patterning in the earliest sharks: Implications for tooth evolution.

    Science.gov (United States)

    Maisey, John G; Turner, Susan; Naylor, Gavin J P; Miller, Randall F

    2014-05-01

    Doliodus problematicus is the oldest known fossil shark-like fish with an almost intact dentition (Emsian, Lower Devonian, c. 397Ma). We provide a detailed description of the teeth and dentition in D. problematicus, based on tomographic analysis of NBMG 10127 (New Brunswick Museum, Canada). Comparisons with modern shark dentitions suggest that Doliodus was a ram-feeding predator with a dentition adapted to seizing and disabling prey. Doliodus provides several clues about the early evolution of the "shark-like" dentition in chondrichthyans and also raises new questions about the evolution of oral teeth in jawed vertebrates. As in modern sharks, teeth in Doliodus were replaced in a linguo-labial sequence within tooth families at fixed positions along the jaws (12-14 tooth families per jaw quadrant in NBMG 10127). Doliodus teeth were replaced much more slowly than in modern sharks. Nevertheless, its tooth formation was apparently as highly organized as in modern elasmobranchs, in which future tooth positions are indicated by synchronized expression of shh at fixed loci within the dental epithelium. Comparable dental arrays are absent in osteichthyans, placoderms, and many "acanthodians"; a "shark-like" dentition, therefore, may be a synapomorphy of chondrichthyans and gnathostomes such as Ptomacanthus. The upper anterior teeth in Doliodus were not attached to the palatoquadrates, but were instead supported by the ethmoid region of the prechordal basicranium, as in some other Paleozoic taxa (e.g., Triodus, Ptomacanthus). This suggests that the chondrichthyan dental lamina was originally associated with prechordal basicranial cartilage as well as jaw cartilage, and that the modern elasmobranch condition (in which the oral dentition is confined to the jaws) is phylogenetically advanced. Thus, oral tooth development in modern elasmobranchs does not provide a complete developmental model for chondrichthyans or gnathostomes. PMID:24347366

  10. Local synthesis and tooth contact analysis of face-milled spiral bevel gears

    Science.gov (United States)

    Litvin, F. L.; Zhang, Y.; Handschuh, R. F.

    1991-01-01

    A new approach is proposed for the local synthesis of spiral bevel gears. The approach provides contact at the mean contact point with the desired deviation of the transmission error function by a predesigned parabolic function. The orientation of the contact path on the gear tooth surface and the length of the major axis of the instantaneous contact ellipse are also included in the analysis. A tooth contact analysis (TCA) computer program was developed to simulate meshing and contact of the gear tooth surfaces. A numerical example of the process is given.

  11. Associations between smoking and tooth loss according to reason for tooth loss

    Science.gov (United States)

    Mai, Xiaodan; Wactawski-Wende, Jean; Hovey, Kathleen M.; LaMonte, Michael J.; Chen, Chaoru; Tezal, Mine; Genco, Robert J.

    2013-01-01

    Background Smoking is associated with tooth loss. However, smoking's relationship to the specific reason for tooth loss in postmenopausal women is unknown. Methods Postmenopausal women (n = 1,106) who joined a Women's Health Initiative ancillary study (The Buffalo OsteoPerio Study) underwent oral examinations for assessment of the number of missing teeth, as well as the self-reported reasons for tooth loss. The authors obtained information about smoking status via a self-administered questionnaire. The authors calculated odds ratios (ORs) and 95 percent confidence intervals (CIs) by means of logistic regression to assess smoking's association with overall tooth loss, as well as with tooth loss due to periodontal disease (PD) and with tooth loss due to caries. Results After adjusting for age, education, income, body mass index (BMI), history of diabetes diagnosis, calcium supplement use and dental visit frequency, the authors found that heavy smokers (≥ 26 pack-years) were significantly more likely to report having experienced tooth loss compared with never smokers (OR = 1.82; 95 percent CI, 1.10-3.00). Smoking status, packs smoked per day, years of smoking, pack-years and years since quitting smoking were significantly associated with tooth loss due to PD. For pack-years, the association for heavy smokers compared with that for never smokers was OR = 6.83 (95 percent CI, 3.40-13.72). The study results showed no significant associations between smoking and tooth loss due to caries. Conclusions and Practical Implications Smoking may be a major factor in tooth loss due to PD. However, smoking appears to be a less important factor in tooth loss due to caries. Further study is needed to explore the etiologies by which smoking is associated with different types of tooth loss. Dentists should counsel their patients about the impact of smoking on oral health, including the risk of tooth loss due to PD. PMID:23449901

  12. Microradiographic investigations on experimentally provoked structural alterations in hard tooth tissues after sealing with plastic material in places where caries is apt to develop

    International Nuclear Information System (INIS)

    The aim of the present investigation was, after sealing three areas in extracted human teeth: fissures, dental necksand approximate areas and subsequent exposure to experimentally produced cariogenous noxae, to establish possible alterations in the area of transition between sealed and unsealed dental enamal. This would provide a further decision-taking aid with regard to the question whether also the remaining parts where caries is apt to develop should be sealed. (orig./MG)

  13. Description of a collaborative community approach to impacting juvenile arrests.

    Science.gov (United States)

    Barrett, James G; Janopaul-Naylor, Elizabeth

    2016-05-01

    Although the burden of mental health disorders among youth involved with the juvenile justice system is high, few communities have effectively integrated mental health resources with law enforcement (Myers & Farrell, 2008). The city of Cambridge, Massachusetts has developed the Safety Net Collaborative, which is a multiagency integrated model of preventive services for at-risk youth involving mental health providers, police officers, schools, and the department of youth and families. There are 6,000 youth in the city's public schools under the local police jurisdiction. Youth are referred to this program by schools, courts, and parents. There are approximately 30 active cases each year. Initial outcome measures were tracked, including number of arrests, diversions, and mental health referrals. Rate of decline in arrests was compared pre and post implementation. Community arrests have decreased by more than 50% since implementing this model. Contracting with mental health services has led to an average 94 outpatient mental health provider referral per year. The results show positive trends in arrest rates after implementation of this collaborative model of preventive services. These findings support greater research and utilization of integrated, preventive service models for at-risk youth. (PsycINFO Database Record PMID:27148947

  14. Tooth fractures in canine clinical practice

    International Nuclear Information System (INIS)

    Tooth fractures constitute a considerable fraction of all tooth diseases. Out of the 5,370 dogs treated during four years, 492 were presented with dental problems and 28.3 % of the latter were treated for tooth fractures. Canines were the most frequently affected teeth (38.8 %), followed by premolars (33.1 %), incisors (25.9 %), and molars (2.2 %), 55.4 % of the patients with canine and incisor fractures being large breed dogs. Fractures of premolars (mostly of 108, 208) were divided evenly irrespective of breed or body size. Nonsurgical endodontic treatment yielded good therapeutic results in most cases, but repeated treatment was necessary in some patients

  15. Chromosomal Aneuploidies and Early Embryonic Developmental Arrest

    Directory of Open Access Journals (Sweden)

    Maria Maurer

    2015-07-01

    Full Text Available Background: Selecting the best embryo for transfer, with the highest chance of achieving a vital pregnancy, is a major goal in current in vitro fertilization (IVF technology. The high rate of embryonic developmental arrest during IVF treatment is one of the limitations in achieving this goal. Chromosomal abnormalities are possibly linked with chromosomal arrest and selection against abnormal fertilization products. The objective of this study was to evaluate the frequency and type of chromosomal abnormalities in preimplantation embryos with developmental arrest. Materials and Methods: This cohort study included blastomeres of embryos with early developmental arrest that were biopsied and analyzed by fluorescence in-situ hybridization (FISH with probes for chromosomes 13, 16, 18, 21 and 22. Forty-five couples undergoing IVF treatment were included, and 119 arrested embryos were biopsied. All probes were obtained from the Kinderwunsch Zentrum, Linz, Austria, between August 2009 and August 2011. Results: Of these embryos, 31.6% were normal for all chromosomes tested, and 68.4% were abnormal. Eleven embryos were uniformly aneuploid, 20 were polyploid, 3 were haploid, 11 displayed mosaicism and 22 embryos exhibited chaotic chromosomal complement. Conclusion: Nearly 70% of arrested embryos exhibit chromosomal errors, making chromosomal abnormalities a major cause of embryonic arrest and may be a further explanation for the high developmental failure rates during culture of the embryos in the IVF setting.

  16. Recommendations to enable drug development for inherited neuropathies: Charcot-Marie-Tooth and Giant Axonal Neuropathy [v2; ref status: indexed, http://f1000r.es/3am

    Directory of Open Access Journals (Sweden)

    Lori Sames

    2014-04-01

    Full Text Available Approximately 1 in 2500 Americans suffer from Charcot-Marie-Tooth (CMT disease. The underlying disease mechanisms are unique in most forms of CMT, with many point mutations on various genes causing a toxic accumulation of misfolded proteins. Symptoms of the disease often present within the first two decades of life, with CMT1A patients having reduced compound muscle and sensory action potentials, slow nerve conduction velocities, sensory loss, progressive distal weakness, foot and hand deformities, decreased reflexes, bilateral foot drop and about 5% become wheelchair bound. In contrast, the ultra-rare disease Giant Axonal Neuropathy (GAN is frequently described as a recessively inherited condition that results in progressive nerve death. GAN usually appears in early childhood and progresses slowly as neuronal injury becomes more severe and leads to death in the second or third decade. There are currently no treatments for any of the forms of CMTs or GAN. We suggest that further clinical studies should analyse electrical impedance myography as an outcome measure for CMT. Further, additional quality of life (QoL assessments for these CMTs are required, and we need to identify GAN biomarkers as well as develop new genetic testing panels for both diseases. We propose that using the Global Registry of Inherited Neuropathy (GRIN could be useful for many of these studies. Patient advocacy groups and professional organizations (such as the Hereditary Neuropathy Foundation (HNF, Hannah's Hope Fund (HHF, The Neuropathy Association (TNA and the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM can play a central role in educating clinicians and patients. Undertaking these studies will assist in the correct diagnosis of disease recruiting patients for clinical studies, and will ultimately improve the endpoints for clinical trials. By addressing obstacles that prevent industry investment in various forms of inherited neuropathies

  17. Recommendations to enable drug development for inherited neuropathies: Charcot-Marie-Tooth and Giant Axonal Neuropathy [v1; ref status: indexed, http://f1000r.es/33n

    Directory of Open Access Journals (Sweden)

    Lori Sames

    2014-04-01

    Full Text Available Approximately 1 in 2500 Americans suffer from Charcot-Marie-Tooth (CMT disease. The underlying disease mechanisms are unique in most forms of CMT, with many point mutations on various genes causing a toxic accumulation of misfolded proteins. Symptoms of the disease often present within the first two decades of life, with CMT1A patients having reduced compound muscle and sensory action potentials, slow nerve conduction velocities, sensory loss, progressive distal weakness, foot and hand deformities, decreased reflexes, bilateral foot drop and about 5% become wheelchair bound. In contrast, the ultra-rare disease Giant Axonal Neuropathy (GAN is frequently described as a recessively inherited condition that results in progressive nerve death. GAN usually appears in early childhood and progresses slowly as neuronal injury becomes more severe and leads to death in the second or third decade. There are currently no treatments for any of the forms of CMTs or GAN. We suggest that further clinical studies should analyse electrical impedance myography as an outcome measure for CMT. Further, additional quality of life (QoL assessments for these CMTs are required, and we need to identify GAN biomarkers as well as develop new genetic testing panels for both diseases. We propose that using the Global Registry of Inherited Neuropathy (GRIN could be useful for many of these studies. Patient advocacy groups and professional organizations (such as the Hereditary Neuropathy Foundation (HNF, Hannah's Hope Fund (HHF, The Neuropathy Association (TNA and the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM can play a central role in educating clinicians and patients. Undertaking these studies will assist in the correct diagnosis of disease recruiting patients for clinical studies, and will ultimately improve the endpoints for clinical trials. By addressing obstacles that prevent industry investment in various forms of inherited neuropathies

  18. Immediate Esthetic Rehabilitation of Periodontally Compromised Anterior Tooth Using Natural Tooth as Pontic

    OpenAIRE

    K. Pavan Kumar; Surya Kumari Nujella; S. Sujatha Gopal; K. Karthik Roy

    2016-01-01

    For patients who require removal of anterior teeth and their replacement various treatment modalities are available. With advancement in technology and availability of glass/polyethylene fibres, use of natural tooth as pontic with fibre reinforced composite restorations offers the promising results. The present case report describes management of periodontally compromised mandibular anterior tooth using natural tooth pontic with fibre reinforcement. A 1-year follow-up showed that the bridge w...

  19. Immediate Esthetic Rehabilitation of Periodontally Compromised Anterior Tooth Using Natural Tooth as Pontic.

    Science.gov (United States)

    Kumar, K Pavan; Nujella, Surya Kumari; Gopal, S Sujatha; Roy, K Karthik

    2016-01-01

    For patients who require removal of anterior teeth and their replacement various treatment modalities are available. With advancement in technology and availability of glass/polyethylene fibres, use of natural tooth as pontic with fibre reinforced composite restorations offers the promising results. The present case report describes management of periodontally compromised mandibular anterior tooth using natural tooth pontic with fibre reinforcement. A 1-year follow-up showed that the bridge was intact with good esthetics and no problem was reported. PMID:27195156

  20. Immediate Esthetic Rehabilitation of Periodontally Compromised Anterior Tooth Using Natural Tooth as Pontic

    Science.gov (United States)

    Kumar, K. Pavan; Nujella, Surya Kumari; Gopal, S. Sujatha

    2016-01-01

    For patients who require removal of anterior teeth and their replacement various treatment modalities are available. With advancement in technology and availability of glass/polyethylene fibres, use of natural tooth as pontic with fibre reinforced composite restorations offers the promising results. The present case report describes management of periodontally compromised mandibular anterior tooth using natural tooth pontic with fibre reinforcement. A 1-year follow-up showed that the bridge was intact with good esthetics and no problem was reported. PMID:27195156

  1. A comparative examination of odontogenic gene expression in both toothed and toothless amniotes

    OpenAIRE

    Lainoff, Alexis J.; Moustakas-Verho, Jacqueline E.; Hu, Diane; Kallonen, Aki; Marcucio, Ralph S.; Hlusko, Leslea J.

    2015-01-01

    A well-known tenet of murine tooth development is that BMP4 and FGF8 antagonistically initiate odontogenesis, but whether this tenet is conserved across amniotes is largely unexplored. Moreover, changes in BMP4-signaling have previously been implicated in evolutionary tooth loss in Aves. Here we demonstrate that Bmp4, Msx1, and Msx2 expression is limited proximally in the red-eared slider turtle (Trachemys scripta) mandible at stages equivalent to those at which odontogenesis is initiated in ...

  2. Electron transport across a quantum wire embedding a saw-tooth superlattice

    Institute of Scientific and Technical Information of China (English)

    Chen Yuan-Ping; Yan Xiao-Hong; Lu Mao-Wang; Deng Yu-Xiang

    2004-01-01

    By developing the recursive Green function method, the transport properties through a quantum wire embedding a finite-length saw-tooth superlattice are studied in the presence of magnetic field. The effects of magnetic modulation and the geometric structures of the superlattice on transmission coefficient are discussed. It is shown that resonant electron gas. The transmission spectrum can be tailored to match requirements through adjusting the size of saw-tooth quantum dot and field strength.

  3. Triclosan-loaded Tooth-binding Micelles for Prevention and Treatment of Dental Biofilm

    OpenAIRE

    Chen, Fu; Rice, Kelly C.; Liu, Xin-Ming; Reinhardt, Richard A.; Bayles, Kenneth W.; Wang, Dong

    2010-01-01

    The purpose of the present study was to develop tooth-binding micelle formulations and evaluate their ability to both inhibit initial biofilm formation as well as decrease the viability of preformed biofilm using an in vitro dental biofilm model. Alendronate (ALN, a bisphosphonate) was covalently attached to the ends of different Pluronic copolymers to confer tooth-binding ability to the micelles, and triclosan was used as a model drug. Based on different micelle preparation methods, Pluronic...

  4. Specificity protein 7 is not essential for tooth morphogenesis

    OpenAIRE

    Clarke, John C.; Bae, Ji-Myung; Adhami, Mitra; Rashid, Harunur; Chen, Haiyan; Napierala, Dobrawa; Gutierrez, Soraya E; Sinha, Krishna; de Crombrugghe, Benoit; Javed, Amjad

    2014-01-01

    Tooth formation is a multifaceted process involving numerous interactions between oral epithelium and neural crest derived ecto-mesenchyme from morphogenesis to cytodifferentiation. The precise molecular regulator that drives the cyto-differentiation and dynamic cross-talk between the two cell types has yet to be fully understood. Runx2 along with its downstream target Sp7 are essential transcription factors for development of the mineralizing cell types. Global knockout of the Runx2 gene res...

  5. Temporal differences in out-of-hospital cardiac arrest incidence and survival

    DEFF Research Database (Denmark)

    Bagai, Akshay; McNally, Bryan F.; Al-Khatib, Sana M.;

    2013-01-01

    Understanding temporal differences in the incidence and outcomes of out-of-hospital cardiac arrest (OHCA) has important implications for developing preventative strategies and optimizing systems for OHCA care....

  6. Impacted supernumerary tooth in coronoid process: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Won Se; Lee, Je Ho; Park, Hyok; Jung, Ho Gul; Kim, Kee Deog [Yonsei University College of Dentistry, Seoul (Korea, Republic of)

    2010-06-15

    Impaction of tooth is a situation in which an unerupted tooth is wedged against another tooth or teeth or otherwise located so that it cannot erupt normally. The supernumerary tooth is also called as hyperdontia and defined as the condition of having additional tooth to the regular number of teeth. The most common supernumerary tooth is a mesiodens, which is a mal-formed, peg-like tooth that occurs between the maxillary incisors. The supernumerary tooth is commonly impacted but they are frequently impacted on maxilla. Ectopic impaction of supernumerary tooth on mandibular condyle, coronoid process, ascending ramus, and pterygomandibular space is very rare condition. In this case, we report a case of impacted supernumerary tooth on mandibular sigmoid notch without definite pathologic change.

  7. Robust tooth surface reconstruction by iterative deformation.

    Science.gov (United States)

    Jiang, Xiaotong; Dai, Ning; Cheng, Xiaosheng; Wang, Jun; Peng, Qingjin; Liu, Hao; Cheng, Cheng

    2016-01-01

    Digital design technologies have been applied extensively in dental medicine, especially in the field of dental restoration. The all-ceramic crown is an important restoration type of dental CAD systems. This paper presents a robust tooth surface reconstruction algorithm for all-ceramic crown design. The algorithm involves three necessary steps: standard tooth initial positioning and division; salient feature point extraction using Morse theory; and standard tooth deformation using iterative Laplacian Surface Editing and mesh stitching. This algorithm can retain the morphological features of the tooth surface well. It is robust and suitable for almost all types of teeth, including incisor, canine, premolar, and molar. Moreover, it allows dental technicians to use their own preferred library teeth for reconstruction. The algorithm has been successfully integrated in our Dental CAD system, more than 1000 clinical cases have been tested to demonstrate the robustness and effectiveness of the proposed algorithm. PMID:26638148

  8. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Wednesday, June 08, ... Orofacial Pain? Temporomandibular Joint Disorder Learn what those dental words mean. The Life of a Tooth games ...

  9. Development of an electro-thermal model for ZnO surge arrester under contamination; Desarrollo de un modelo electro-termico para apartarrayos de ZnO bajo contaminacion

    Energy Technology Data Exchange (ETDEWEB)

    Guardado Zavala, J.L.; Moreno Barraza, M.; Zazueta Pena, H.; Venegas Rebollar, V.; Melgoza Vazquez, E. [Instituto Tecnologico de Morelia, Morelia, Michoacan (Mexico)]. E-mail: lguarda@prodigy.net.mx; hzazuetapea@yahoo.com; vvenegas@yahoo.com; emelgoza@iimorelia.edu.mx

    2010-01-15

    An electro-thermal model for a Zinc Oxide (ZnO) surge arrester under contamination test is presented. The model is based in three sub-models: electrical, thermal and contamination, which interact in order to obtain the surge arrester performance under contamination tests. The electrical model is obtained from measurements and is based on a capacitance and a non-linear resistor. The thermal model takes into account the heat generated and dissipated by the column of varistors and its surroundings. The contamination is represented by dynamic impedance obtained from measurements in the arrester column during contamination tests. The full model is validated by calculating the temperature increase during contamination tests carried out in a two units ZnO surge arrester, class 190 kV. Finally, the results of the effect of several design and construction parameters in the voltage and temperature distribution in the arrester column during contamination tests are presented. [Spanish] Se presenta el modelo electro-termico para un apartarrayos de Oxido de Zinc (ZnO) durante pruebas de contaminacion. El modelo esta compuesto de tres sub-modelos: electrico, termico y de contaminacion, los cuales interactuan armonicamente para obtener el comportamiento del apartarrayos durante pruebas de contaminacion. El modelo electrico se obtiene de mediciones y esta compuesto de una capacitancia y una resistencia no-lineal. El modelo termico considera el calor generado y disipado en la columna de varistores y su entorno. La contaminacion se representa como una impedancia dinamica, cuyos valores se obtienen de mediciones en la columna del apartarrayos durante pruebas de contaminacion. El modelo se valida determinando el incremento de temperatura durante pruebas de contaminacion en un apartarrayos de ZnO de dos unidades clase 1990 kV. Finalmente, se presentan los resultados del impacto de diversos parametros de diseno y construccion en la distribucion de voltaje y temperatura en el apartarrayos

  10. Tooth Preparation and Pulpal Response: Literature Review

    OpenAIRE

    ACAR, Dr. Özlem; ERKUT, Doç. Dr. Selim

    2013-01-01

    Pulp tissue reaction to tooth preparation for direct or indirect restorations is one of the major concerns in fixed prosthodontics. Although the sensitivity of dentine to a variety of stimuli is difficult to correlate with morphological and functional observations, hydrodynamic theory was used to explain dental pain mechanism. External stimuli (e.g., thermal, mechanical and dental restorative processes) applied to human tooth cause either an inward (toward the pulp chamber) or outward (away f...

  11. Tooth wear: the view of the anthropologist

    OpenAIRE

    John A. Kaidonis

    2007-01-01

    Anthropologists have for many years considered human tooth wear a normal physiological phenomenon where teeth, although worn, remain functional throughout life. Wear was considered pathological only if pulpal exposure or premature tooth loss occurred. In addition, adaptive changes to the stomatognathic system in response to wear have been reported including continual eruption, the widening of the masticatory cycle, remodelling of the temporomandibular joint and the shortening of the dental ar...

  12. Treatment imprudence leading to missed tooth fragment

    OpenAIRE

    Barua, Pranamee; Chaudhary, Seema; Kaur, Harsimran; Mallikarjuna, Rachappa

    2013-01-01

    Traumatic dental injuries (TDI) represent one of the most common oral health problems in children and adolescents. Dental trauma requires a special consideration when it accompanies soft tissue lacerations. Tooth fragments occasionally penetrate into soft tissues and may cause severe complications. This article describes the case of a 12-year-old girl with a fractured tooth fragment embedded in the lower lip for 4 months, which went unnoticed at her primary health centre. This report highligh...

  13. Full Mouth Rehabilitation with Maxillary Tooth Supported and Mandibular Tooth and Implant Supported Combination Prostheses: A 4-Year Case Report

    OpenAIRE

    Pramod Kumar, A. V.; Vinni, T. K.; Mahesh, Mehul R.

    2012-01-01

    The primary objectives of successful prosthetic rehabilitation are to provide function, esthetics and comfort to the patient. Combination prosthesis is one which is supported by both natural teeth and implant. The periodontal ligament and osseointegrated interface distribute force differently to the supporting bone. Therefore problems can develop when tooth and implants are combined in the same prosthesis. However, clinicians can apply biomechanical principles, to negate the deleterious lever...

  14. Composite Pressure Vessel Including Crack Arresting Barrier

    Science.gov (United States)

    DeLay, Thomas K. (Inventor)

    2013-01-01

    A pressure vessel includes a ported fitting having an annular flange formed on an end thereof and a tank that envelopes the annular flange. A crack arresting barrier is bonded to and forming a lining of the tank within the outer surface thereof. The crack arresting barrier includes a cured resin having a post-curing ductility rating of at least approximately 60% through the cured resin, and further includes randomly-oriented fibers positioned in and throughout the cured resin.

  15. Sonic Hedgehog Opposes Epithelial Cell Cycle Arrest

    OpenAIRE

    Fan, Hongran; Khavari, Paul A

    1999-01-01

    Stratified epithelium displays an equilibrium between proliferation and cell cycle arrest, a balance that is disrupted in basal cell carcinoma (BCC). Sonic hedgehog (Shh) pathway activation appears sufficient to induce BCC, however, the way it does so is unknown. Shh-induced epidermal hyperplasia is accompanied by continued cell proliferation in normally growth arrested suprabasal cells in vivo. Shh-expressing cells fail to exit S and G2/M phases in response to calcium-induced differentiation...

  16. Paclitaxel Arrests Growth of Intracellular Toxoplasma gondii

    OpenAIRE

    Estes, Randee; Vogel, Nicolas; Mack, Douglas; McLeod, Rima

    1998-01-01

    Addition of paclitaxel (Taxol) at a concentration of 1 μM to Toxoplasma gondii-infected human foreskin fibroblasts arrested parasite multiplication. Division of the T. gondii tachyzoite nucleus was inhibited, leading to syncytium-like parasite structures within the fibroblasts by 24 h after infection and treatment of the cultures. By 4 days after infection and treatment of the cultures with paclitaxel, this inhibition was irreversible, since the arrested intracellular form was incapable of le...

  17. Surviving out-of-hospital cardiac arrest.

    Science.gov (United States)

    Evans, Nick

    2016-05-01

    Emergency care nurses have been urged to play their part in Scotland's push to revolutionise care for cardiac arrest patients - by teaching others how to save a life. This article discusses the Scottish out-of-hospital cardiac arrest strategy, with particular focus on the drive to increase bystander cardiopulmonary resuscitation (CPR) rates, and on how emergency nurses are being enlisted to help promote the training of members of the public. PMID:27165393

  18. Enamel microstructure and tooth embryonic development

    Czech Academy of Sciences Publication Activity Database

    Kallistová, Anna; Horáček, I.; Čejchan, Petr; Skála, Roman

    Rovinj: ECM29, 2015. s. 298-298. [European Crystallographic Meeting /29./. 23.08.2015-28.08.2015, Rovinj] Institutional support: RVO:67985831 Keywords : microstructure * crystallography Subject RIV: BM - Solid Matter Physics ; Magnetism http://ecm29.ecanews.org/wp-content/uploads/Book_of_abstracts_ECM29_final.compressed.pdf

  19. Predicting crack arrest in reactor pressure vessels

    International Nuclear Information System (INIS)

    The pressurized thermal shock (PTS) issue has provided increased motivation for the search for a reasonably accurate crack arrest prediction methodology. This issue has assumed greater significance recently as a consequence of the imposition of Regulatory Guide 1.99 Revision 2 procedures for determining the effects of radiation embrittlement in the context of the screening criteria in the PTS rule that is used by the United States Nuclear Regulatory Commission to assess the integrity of reactor pressure vessels. The currently accepted procedure for predicting crack arrest is the so-called KIa procedure, which is based on static linear elastic fracture mechanics principles, with a crack being presumed to arrest when the crack tip stress intensity factor KIST falls below a value KIa. The present paper reviews recent EPRI sponsored research, which shows that the static procedure is overly conservative when it is applied to the first arrest of a deep crack in the thickness of a reactor vessel. This conclusion is clearly important when assessing the consequences of the imposition of the procedures of Regulatory Guide 1.99 Revision 2. A more accurate crack arrest prediction procedure, i.e. the Combustion Engineering constrained static procedure or the reflectionless stress intensity factor procedure which are very similar in concept and their arrest prediction, should be considered to assess the impact of its use in the context of the screening criteria limits in the PTS rule. (orig.)

  20. Towards unraveling the human tooth transcriptome: the dentome.

    Directory of Open Access Journals (Sweden)

    Shijia Hu

    Full Text Available The goal of the study was to characterize the transcriptome profiles of human ameloblasts and odontoblasts, evaluate molecular pathways and advance our knowledge of the human "dentome". Laser capture microdissection was used to isolate odontoblasts and ameloblasts from human tooth buds (15-20week gestational age from 4 fetuses. RNA was examined using Agilent 41k whole genome arrays at 2 different stages of enamel formation, presecretory and secretory. Probe detection was considered against the array negative control to control for background noise. Differential expression was examined using Significance Analysis of Microarrays (SAM 4.0 between different cell types and developmental stages with a false discovery rate of 20%. Pathway analysis was conducted using Ingenuity Pathway Analysis software. We found that during primary tooth formation, odontoblasts expressed 14,802 genes, presecretory ameloblasts 15,179 genes and secretory ameloblasts 14,526 genes. Genes known to be active during tooth development for each cell type (eg COL1A1, AMELX were shown to be expressed by our approach. Exploring further into the list of differentially expressed genes between the motile odontoblasts and non-motile presecretory ameloblasts we found several genes of interest that could be involved in cell movement (FN1, LUM, ASTN1. Furthermore, our analysis indicated that the Phospholipase C and ERK5 pathways, that are important for cell movement, were activated in the motile odontoblasts. In addition our pathway analysis identified WNT3A and TGFB1 as important upstream contributors. Recent studies implicate these genes in the development of Schimke immuno-osseous dysplasia. The utility of laser capture microdissection can be a valuable tool in the examination of specific tissues or cell populations present in human tooth buds. Advancing our knowledge of the human dentome and related molecular pathways provides new insights into the complex mechanisms regulating

  1. Sex Disparities in Arrest Outcomes for Domestic Violence

    Science.gov (United States)

    Hamilton, Melissa; Worthen, Meredith G. F.

    2011-01-01

    Domestic violence arrests have been historically focused on protecting women and children from abusive men. Arrest patterns continue to reflect this bias with more men arrested for domestic violence compared to women. Such potential gender variations in arrest patterns pave the way to the investigation of disparities by sex of the offender in…

  2. Anaphylactic shock and cardiac arrest caused by thiamine infusion

    OpenAIRE

    Juel, Jacob; Pareek, Manan; Langfrits, Christian Sigvald; Jensen, Svend Eggert

    2013-01-01

    Parenteral thiamine has a very high safety profile. The most common adverse effect is local irritation; however, anaphylactic or anaphylactoid reactions may occur, mostly related to intravenous administration. We describe a 44-year-old man, a chronic alcoholic, who was admitted with alcohol intoxication and developed cardiac arrest due to anaphylactic shock following intravenous thiamine infusion. The patient was successfully resuscitated after 15 min and repeated epinephrine administrations....

  3. ADULTHOOD ANIMAL ABUSE AMONG MEN ARRESTED FOR DOMESTIC VIOLENCE

    OpenAIRE

    Febres, Jeniimarie; Brasfield, Hope; Shorey, Ryan C.; Elmquist, Joanna; Ninnemann, Andrew; Schonbrun, Yael C.; Temple, Jeff R.; Recupero, Patricia R.; Stuart, Gregory L.

    2014-01-01

    Learning more about intimate partner violence (IPV) perpetrators could aid the development of more effective treatments. The prevalence of adulthood animal abuse (AAA) perpetration and its association with IPV perpetration, antisociality, and alcohol use in 307 men arrested for domestic violence was examined. 41% (n = 125) of the men committed at least one act of animal abuse since the age of 18, in contrast to the 3.0% prevalence rate reported by men in the general population. Controlling fo...

  4. Osteopontin deficiency enhances parathyroid hormone/ parathyroid hormone related peptide receptor (PPR) signaling-induced alteration in tooth formation and odontoblastic morphology

    OpenAIRE

    Morishita, Maki; Ono, Noriaki; Miyai, Kentano; Nakagawa, Tomomi; Hanyu, Ryo; Nagao, Masashi; Kamolratanakul, Paksinee; Notomi, Takuya; Rittling, Susan R; Denhardt, David T.; Kronenberg, Henry M.; Ezura, Yoichi; Hayata, Tadayoshi; Nakamoto, Tetsuya; Noda, Masaki

    2011-01-01

    Parathyroid hormone/parathyroid hormone-related protein receptor (PPR) signaling is known to be involved in tooth development. In bone, extracellular matrix protein osteopontin (OPN) is a negative regulator of PPR signaling in bone formation. However, the role of OPN in modulation of PPR action in tooth development is not understood. Therefore, we examined the tooth in double mutant mice. Constitutively active PPR was expressed specifically in the odontoblasts and osteoblasts (caPPR-tg) in th...

  5. Pediatric defibrillation after cardiac arrest: initial response and outcome

    Science.gov (United States)

    Rodríguez-Núñez, Antonio; López-Herce, Jesús; García, Cristina; Domínguez, Pedro; Carrillo, Angel; Bellón, Jose María

    2006-01-01

    Introduction Shockable rhythms are rare in pediatric cardiac arrest and the results of defibrillation are uncertain. The objective of this study was to analyze the results of cardiopulmonary resuscitation that included defibrillation in children. Methods Forty-four out of 241 children (18.2%) who were resuscitated from inhospital or out-of-hospital cardiac arrest had been treated with manual defibrillation. Data were recorded according to the Utstein style. Outcome variables were a sustained return of spontaneous circulation (ROSC) and one-year survival. Characteristics of patients and of resuscitation were evaluated. Results Cardiac disease was the major cause of arrest in this group. Ventricular fibrillation (VF) or pulseless ventricular tachycardia (PVT) was the first documented electrocardiogram rhythm in 19 patients (43.2%). A shockable rhythm developed during resuscitation in 25 patients (56.8%). The first shock (dose, 2 J/kg) terminated VF or PVT in eight patients (18.1%). Seventeen children (38.6%) needed more than three shocks to solve VF or PVT. ROSC was achieved in 28 cases (63.6%) and it was sustained in 19 patients (43.2%). Only three patients (6.8%), however, survived at 1-year follow-up. Children with VF or PVT as the first documented rhythm had better ROSC, better initial survival and better final survival than children with subsequent VF or PVT. Children who survived were older than the finally dead patients. No significant differences in response rate were observed when first and second shocks were compared. The survival rate was higher in patients treated with a second shock dose of 2 J/kg than in those who received higher doses. Outcome was not related to the cause or the location of arrest. The survival rate was inversely related to the duration of cardiopulmonary resuscitation. Conclusion Defibrillation is necessary in 18% of children who suffer cardiac arrest. Termination of VF or PVT after the first defibrillation dose is achieved in a low

  6. Adhesion of Dental Materials to Tooth Structure

    Science.gov (United States)

    Mitra, Sumita B.

    2000-03-01

    The understanding and proper application of the principles of adhesion has brought forth a new paradigm in the realm of esthetic dentistry. Modern restorative tooth procedures can now conserve the remaining tooth-structure and also provide for the strengthening of the tooth. Adhesive restorative techniques call for the application and curing of the dental adhesive at the interface between the tooth tissue and the filling material. Hence the success of the restoration depends largely on the integrity of this interface. The mechanism of adhesion of the bonding materials to the dental hard tissue will be discussed in this paper. There are four main steps that occur during the application of the dental adhesive to the oral hard tissues: 1) The first step is the creation of a microstructure in the tooth enamel or dentin by means of an acidic material. This can be through the application of a separate etchant or can be accomplished in situ by the adhesive/primer. This agent has to be effective in removing or modifying the proteinaceous “smear” layer, which would otherwise act as a weak boundary layer on the surface to be bonded. 2) The primer/adhesive must then be able to wet and penetrate the microstructure created in the tooth. Since the surface energies of etched enamel and that of etched dentin are different finding one material to prime both types of dental tissues can be quite challenging. 3) The ionomer types of materials, particularly those that are carboxylate ion-containing, can chemically bond with the calcium ions of the hydroxyapatite mineral. 4) Polymerization in situ allows for micromechanical interlocking of the adhesive. The importance of having the right mechanical properties of the cured adhesive layer and its role in absorbing and dissipating stresses encountered by a restored tooth will also be discussed.

  7. A possible etiology for the dilaceration and flexion of permanent tooth roots relative to bone remodeling gradients in alveolar bone

    Directory of Open Access Journals (Sweden)

    Richard G Standerwick

    2014-01-01

    Full Text Available Introduction: Trauma, altered tooth germ position and delayed tooth eruption have been hypothesized as possible causes of tooth root dilacerations and flexion, however these anatomical variations appear more commonly associated with posterior teeth and absence of traumatic history. The Hypothesis: Postulated is that tooth root dilaceration or flexion may be a result of tooth root sheath displacement due to gradients of bone remodeling present within alveolar bone. Evaluation of the Hypothesis: Alveolar bone displays bone remodeling gradients between coronal, apical and basal sections which affect bone plasticity. As a tooth is erupting or experiences delayed eruption, there are other relative dento-skeletal alterations occurring, such as the mesial drift of the dentition and transverse growth of the maxilla. It is plausible that during the physiologic and growth related alteration of the alveolar and basal bones, portions of developing tooth could be found within one or more of the plasticity zones, contributing to alteration of the root sheath and tooth root dilaceration.

  8. Platelet-rich fibrin-mediated revitalization of immature necrotic tooth

    Directory of Open Access Journals (Sweden)

    Navin Mishra

    2013-01-01

    Full Text Available Contemporary studies have shown that the regeneration of tissues and root elongation is possible in necrotic immature permanent teeth. The purpose of this case report is to add a new vista in regenerative endodontic therapy by using platelet rich fibrin for revitalization of immature non vital tooth. An 11year old boy with the history of trauma was diagnosed with the pulpal necrosis and symptomatic apical periodontitis in tooth #21. Intra oral periapical radiograph showed open apex and associated immature supernumerary tooth with respect to tooth #21. Access preparation and minimal instrumentation was done to remove necrotic debris under copious irrigation with 2.5% sodium hypochlorite. Triple antibiotic paste was packed in the canal for four weeks. During second visit, 5 mL of whole blood was drawn from the medial cubital vein of the patient and blood was then subjected to centrifugation at 2400 rpm for 12 minutes for the preparation of Platelet rich fibrin (PRF utilizing Choukroun′s method. Triple antibiotic paste was removed and canal was dried. PRF clot was pushed to the apical region of tooth #21 using hand pluggers. Three milimetres of Mineral trioxide (MTA was placed in cervical part of the root canal and permanent restoration was done three days later. Clinical examination at 6 and 12 months revealed no sensitivity to percussion and palpation in tooth #21and it responded positively to both electric pulp and cold tests. Radiographic examination showed resolution of periapical rarefaction, further root development and apical closure of the tooth #21 and its associated supernumerary tooth. On the basis of successful outcome of the present case it can be stated that PRF clot may serve as a scaffold for regeneration of necrotic immature teeth.

  9. Unicuspid and bicuspid tooth crown formation in squamates.

    Science.gov (United States)

    Handrigan, Gregory R; Richman, Joy M

    2011-12-15

    The molecular and developmental factors that regulate tooth morphogenesis in nonmammalian species, such as snakes and lizards, have received relatively little attention compared to mammals. Here we describe the development of unicuspid and bicuspid teeth in squamate species. The simple, cone-shaped tooth crown of the bearded dragon and ball python is established at cap stage and fixed in shape by the differentiation of cells and the secretion of dental matrices. Enamel production, as demonstrated by amelogenin expression, occurs relatively earlier in squamate teeth than in mouse molars. We suggest that the early differentiation in squamate unicuspid teeth at cap stage correlates with a more rudimentary tooth crown shape. The leopard gecko can form a bicuspid tooth crown despite the early onset of differentiation. Cusp formation in the gecko does not occur by the folding of the inner enamel epithelium, as in the mouse molar, but by the differential secretion of enamel. Ameloblasts forming the enamel epithelial bulge, a central swelling of cells in the inner enamel epithelium, secrete amelogenin at cap stage, but cease to do so by bell stage. Meanwhile, other ameloblasts in the inner enamel epithelium continue to secrete enamel, forming cusp tips on either side of the bulge. Bulge cells specifically express the gene Bmp2, which we suggest serves as a pro-differentiation signal for cells of the gecko enamel organ. In this regard, the enamel epithelial bulge of the gecko may be more functionally analogous to the secondary enamel knot of mammals than the primary enamel knot. PMID:21932327

  10. Tooth-surface-specific Effects of Xylitol

    Science.gov (United States)

    Ritter, A.V.; Bader, J.D.; Leo, M.C.; Preisser, J.S.; Shugars, D.A.; Vollmer, W.M.; Amaechi, B.T.; Holland, J.C.

    2013-01-01

    The Xylitol for Adult Caries Trial was a three-year, double-blind, multi-center, randomized clinical trial that evaluated the effectiveness of xylitol vs. placebo lozenges in the prevention of dental caries in caries-active adults. The purpose of this secondary analysis was to investigate whether xylitol lozenges had a differential effect on cumulative caries increments on different tooth surfaces. Participants (ages 21-80 yrs) with at least one follow-up visit (n = 620) were examined at baseline, 12, 24, and 33 months. Negative binomial and zero-inflated negative binomial regression models were used to estimate incidence rate ratios (IRR) for xylitol’s differential effect on cumulative caries increments on root and coronal surfaces and, among coronal surfaces, on smooth (buccal and lingual), occlusal, and proximal surfaces. Participants in the xylitol arm developed 40% fewer root caries lesions (0.23 D2FS/year) than those in the placebo arm (0.38 D2FS/year; IRR = 0.60; 95% CI [0.44, 0.81]; p < .001). There was no statistically significant difference between xylitol and control participants in the incidence of smooth-surface caries (p = .100), occlusal-surface caries (p = .408), or proximal-surface caries (p = .159). Among these caries-active adults, xylitol appears to have a caries-preventive effect on root surfaces (ClinicalTrials.gov NCT00393055). PMID:23589387

  11. Advances in crack-arrest technology for reactor pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Bass, B.R.; Pugh, C.E.

    1988-01-01

    The Heavy-Section Steel Technology (HSST) Program at the Oak Ridge National Laboratory (ORNL) under the sponsorship of the US Nuclear Regulatory Commission is continuing to improve the understanding of conditions that govern the initiation, rapid propagation, arrest, and ductile tearing of cracks in reactor pressure vessel (RPV) steels. This paper describes recent advances in a coordinated effort being conducted under the HSST Program by ORNL and several subcontracting groups to develop the crack-arrest data base and the analytical tools required to construct inelastic dynamic fracture models for RPV steels. Large-scale tests are being carried out to generate crack-arrest toughness data at temperatures approaching and above the onset of Charpy upper-shelf behavior. Small- and intermediate-size specimens subjected to static and dynamic loading are being developed and tested to provide additional fracture data for RPV steels. Viscoplastic effects are being included in dynamic fracture models and computer programs and their utility validated through analyses of data from carefully controlled experiments. Recent studies are described that examine convergence problems associated with energy-based fracture parameters in viscoplastic-dynamic fracture applications. Alternative techniques that have potential for achieving convergent solutions for fracture parameters in the context of viscoplastic-dynamic models are discussed. 46 refs., 15 figs., 3 tabs.

  12. Soft Semicrystalline Thermoplastic Elastomers by Arrested Crystallization

    Science.gov (United States)

    Burns, Adam; Register, Richard

    2014-03-01

    Thermoplastic elastomers (TPEs) marry the solid-state behavior of vulcanized rubbers with the melt processability of thermoplastics. Archetypal soft TPEs consist of triblock copolymers comprising a rubbery mid-block flanked by two identical glassy end-blocks. Incorporating crystalline blocks into TPEs can confer solvent resistance as well as reduce the processing costs by giving access to single-phase melts. However, simply substituting crystalline for glassy end-blocks dramatically degrades the solid-state mechanical properties, particularly at large strains. We seek to integrate the benefits of crystallinity into TPEs, while maintaining the desired mechanical properties, using the block architecture: crystalline-glassy-rubbery-glassy-crystalline. Methods have been developed to synthesize highly symmetric, narrow-distribution block copolymers with this architecture using anionic polymerization of butadiene, styrene, and isoprene followed by hydrogenation. Judicious choices of block molecular weights indeed yield homogeneous melts above the melting point of the crystalline component. Upon cooling, crystallization--rather than interblock repulsion--establishes the solid-state microstructure which physically crosslinks the rubbery mid-block, ultimately conferring elasticity. Subsequent vitrification of the adjacent glassy blocks arrests the growth of the crystallites, and protects them from yielding under applied load. As a result, our materials show low initial moduli, strain hardening, and high extensibility, typical of commercial TPEs.

  13. Crack arrest saturation model under combined electrical and mechanical loadings

    Directory of Open Access Journals (Sweden)

    R.R. Bhargava

    2009-12-01

    Full Text Available Purpose: The investigation aims at proposing a model for cracked piezoelectric strip which is capable to arrest the crack.Design/methodology/approach: Under the combined effect of electrical and mechanical loadings applied at the edges of the strip, the developed saturation zone is produced at each tip of the crack. To arrest further opening of the crack, the rims of the developed saturation zones are subjected to in-plane cohesive, normal uniform constant saturation point electrical displacement. The problem is solved using Fourier integral transform method which reduces the problem to the solution of Fredholm integral equation of the second kind. This integral equation in turn is solved numerically.Findings: The expressions are derived for different intensity factors and energy release rate. A qualitative analysis of the parameters affecting the arrest of opening of the crack and fatigue crack growth with respect to strip thickness and material constants are presented graphically.Research limitations/implications: The investigations are carried out by considering the material electrical brittle. Consequently, the zones protrude along the straight lines ahead of the crack tips. And further, the small scale electrical yielding conditions are used.Practical implications: Piezoelectric materials are widely getting used nowadays, even in day to day life like piezoelectric cigarette lighter, children toys etc. And, its advance used in technology like transducers, actuators has been already in progress. So, the aspect of cracking of piezoelectric materials are of great practical importance.Originality/value: The piezoelectric material under the combined effect of electrical and mechanical loadings gives the assessment of electrical displacement which is required to arrest the crack. The various useful interpretations are also drawn from the graphs.

  14. Controlled Deposition of HAp Mimicking Tooth Enamel

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Chemical compositions and microsturcture of mature human tooth enamel were investigated by XRD , FTIR and SEM to further understand the characteristics of tooth enamel. In order to obtain apatite crystals chemically and structurally similar to those in tooth enamel, biomimetic way was employed. Selfassembled monolyers terminated with-SO3 H groups were used as deposition substrates and 1.5 SBF ( the concentrations of Ca2+ and PO43- ions 1.5 times than those in simulated body fluid ) with and without 5 ppm F- were used as soaking medium. The XRD and FTIR results showed that both the deposited fluoride-substituted hydroxyapatite( F-HAp ) crystals in 1.5 SBF with F- and hydroxyapatite ( HAp ) crystals in 1.5 SBF were carbonate-containing, mimicking human tooth enamel in chemical compositions. The SEM photos showed that needle-like F-HAp crystals bad large aspect ratios and grew in bundles, which were similar to the crystals in human tooth enamel.The results provide available information on dental restoration.

  15. Therapeutic Hypothermia and Out-of-Hospital Cardiac Arrest in a Child with Hypertrophic Obstructive Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Nancy Spurkeland

    2015-01-01

    Full Text Available Neurologic outcomes following pediatric cardiac arrest are consistently poor. Early initiation of cardiopulmonary resuscitation has been shown to have positive effects on both survival to hospital discharge, and improved neurological outcomes after cardiac arrest. Additionally, the use of therapeutic hypothermia may improve survival in pediatric cardiac arrest patients admitted to the intensive care unit. We report a child with congenital hypertrophic obstructive cardiomyopathy and an out-of-hospital cardiac arrest, in whom the early initiation of effective prolonged cardiopulmonary resuscitation and subsequent administration of therapeutic hypothermia contributed to a positive outcome with no gross neurologic sequelae. Continuing efforts should be made to promote and employ high-quality cardiopulmonary resuscitation, which likely contributed to the positive outcome of this case. Further research will be necessary to develop and solidify national guidelines for the implementation of therapeutic hypothermia in selected subpopulations of children with OHCA.

  16. Hyperoxia toxicity after cardiac arrest: What is the evidence?

    Science.gov (United States)

    Llitjos, Jean-François; Mira, Jean-Paul; Duranteau, Jacques; Cariou, Alain

    2016-12-01

    This review gives an overview of current knowledge on hyperoxia pathophysiology and examines experimental and human evidence of hyperoxia effects after cardiac arrest. Oxygen plays a pivotal role in critical care management as a lifesaving therapy through the compensation of the imbalance between oxygen requirements and supply. However, growing evidence sustains the hypothesis of reactive oxygen species overproduction-mediated toxicity during hyperoxia, thus exacerbating organ failure by various oxidative cellular injuries. In the cardiac arrest context, evidence of hyperoxia effects on outcome is fairly conflicting. Although prospective data are lacking, retrospective studies and meta-analysis suggest that hyperoxia could be associated with an increased mortality. However, data originate from retrospective, heterogeneous and inconsistent studies presenting various biases that are detailed in this review. Therefore, after an original and detailed analysis of all experimental and clinical studies, we herein provide new ideas and concepts that could participate to improve knowledge on oxygen toxicity and help in developing further prospective controlled randomized trials on this topic. Up to now, the strategy recommended by international guidelines on cardiac arrest (i.e., targeting an oxyhemoglobin saturation of 94-98 %) should be applied in order to avoid deleterious hypoxia and potent hyperoxia. PMID:27003426

  17. Master curve based correlation between static initiation toughness KIC and crack arrest toughness KIa

    International Nuclear Information System (INIS)

    Historically the ASME reference curve concept assumes a constant relation between static fracture toughness initiation toughness and crack arrest toughness. In reality, this is not the case. Experimental results show that the difference between KIC and KIa is material specific. For some materials there is a big difference while for others they nearly coincide. So far, however, no systematic study regarding a possible correlation between the two parameters has been performed. The recent Master curve method, developed for brittle fracture initiation estimation, has enabled a consistent analysis of fracture initiation toughness data. The Master curve method has been modified to be able to describe also crack arrest toughness. Here, this modified 'crack arrest master curve' is further validated and used to develop a simple, but yet (for safety assessment purpose) adequately accurate correlation between the two fracture toughness parameters. The correlation enables the estimation of crack arrest toughness from small Charpy-sized static fracture toughness tests. The correlation is valid for low Nickel steels ≤ (1.2% Ni). If a more accurate description of the crack arrest toughness is required, it can either be measured experimentally or estimated from instrumented Charpy-V crack arrest load information. (orig.)

  18. Tooth-germ damage by ionizing radiation

    International Nuclear Information System (INIS)

    Experiments on animals (four-week-old dogs) were conducted in an investigation made to study the possibility of dose-dependent tooth-germ damage produced by ionizing radiation. The individual doses were 50 R and 200 R, respectively, and they were administered once to three times at weekly intervals. Hyperemia and edemata could be observed on tooth-germ pulps from 150 R onward. Both of these conditions became more acute as the radiation dose increased (from 150 R to 600 R). Possible damage to both the dentin and enamel is pointed out. (author)

  19. Immediate Esthetic Rehabilitation of Periodontally Compromised Anterior Tooth Using Natural Tooth as Pontic

    Directory of Open Access Journals (Sweden)

    K. Pavan Kumar

    2016-01-01

    Full Text Available For patients who require removal of anterior teeth and their replacement various treatment modalities are available. With advancement in technology and availability of glass/polyethylene fibres, use of natural tooth as pontic with fibre reinforced composite restorations offers the promising results. The present case report describes management of periodontally compromised mandibular anterior tooth using natural tooth pontic with fibre reinforcement. A 1-year follow-up showed that the bridge was intact with good esthetics and no problem was reported.

  20. Seal Out Tooth Decay: A Fact Sheet for Parents

    Science.gov (United States)

    ... Institute of Dental and Craniofacial Research Seal Out Tooth Decay A Fact Sheet for Parents What are dental ... important reason for getting sealants is to avoid tooth decay. • Fluoride in toothpaste and in drinking water protects ...

  1. The relationship between gastroesophageal reflux disease and tooth decay?

    OpenAIRE

    ÖZKAN, Buğra; FİLİK, Levent; SAĞLAM, Osman

    2014-01-01

    Backgaround and Aims: The aim of this study was to show the relationship of gastroesophageal reflux disease and tooth decay. The most common cause of tooth decay is poor oral hygiene but gastric contents may also cause poor oral hygiene and tooth decay. In this study, we hypothesized and investigated whether gastroesophageal reflux disease caused tooth decay. Materials and Methods:Sixty-five patients were studied; 30 patients had gastroesophageal reflux disease, with disease diagnosis...

  2. Ectopic located tooth which obstrcuted the maxillary sinus ostium

    OpenAIRE

    Atalay Erdogan, Banu; Paksoy, Mustafa; Sanli, Arif; Altin, Gokhan; Bekmez, Eda

    2012-01-01

    A giant mucocele secondary to obstruction of the maxillary sinus ostium with an ectopic tooth. Mucocele secondary to ectopic maxillary tooth is very rare. We present a case of giant mucocele which is caused by obstruction of the maxillary sinus ostium with an ectopic tooth. The patient presented with headache and facial asymmetry. CT of the paranasal sinuses revealed an ectopic maxillary tooth, obstructing the maxillary sinus ostium and a mucocele of the maxillary sinus that erodes bony w...

  3. Tooth width ratios in crowded and non-crowded dentitions

    OpenAIRE

    Bernabé, E.; Villanueva, KM; Flores-Mir, C

    2004-01-01

    Discrepancies in tooth width ratios could affect the excellence in the finishing of orthodontic cases. This study compares tooth width ratios in crowded and noncrowded dental arches. Tooth widths were measured from 143 dental casts (40 crowded and 33 spaced in male individuals and 43 crowded and 27 spaced in female individuals). Simultaneous crowded or spaced arches were selected. Tooth width measurements were made with a sliding caliper with a Vernier scale neared 0.1 mm. Inter- (0.990) and ...

  4. Local stresses, dyke arrest and surface deformation in volcanic edificesand rift zones

    Directory of Open Access Journals (Sweden)

    L. S. Brenner

    2004-06-01

    Full Text Available Field studies indicate that nearly all eruptions in volcanic edifices and rift zones are supplied with magma through fractures (dykes that are opened by magmatic overpressure. While (inferred dyke injections are frequent during unrest periods, volcanic eruptions are, in comparison, infrequent, suggesting that most dykes become arrested at certain depths in the crust, in agreement with field studies. The frequency of dyke arrest can be partly explained by the numerical models presented here which indicate that volcanic edifices and rift zones consisting of rocks of contrasting mechanical properties, such as soft pyroclastic layers and stiff lava flows, commonly develop local stress fields that encourage dyke arrest. During unrest, surface deformation studies are routinely used to infer the geometries of arrested dykes, and some models (using homogeneous, isotropic half-spaces infer large grabens to be induced by such dykes. Our results, however, show that the dyke-tip tensile stresses are normally much greater than the induced surface stresses, making it difficult to explain how a dyke can induce surface stresses in excess of the tensile (or shear strength while the same strength is not exceeded at the (arrested dyke tip. Also, arrested dyke tips in eroded or active rift zones are normally not associated with dyke-induced grabens or normal faults, and some dykes arrested within a few metres of the surface do not generate faults or grabens. The numerical models show that abrupt changes in Young's moduli(stiffnesses, layers with relatively high dyke-normal compressive stresses (stress barriers, and weak horizontal contacts may make the dyke-induced surface tensile stresses too small for significant fault or graben formation to occur in rift zones or volcanic edifices. Also, these small surface stresses may have no simple relation to the dyke geometry or the depth to its tip. Thus, for a layered crust with weak contacts, straightforward

  5. The Importance of Tooth Decay Prevention in Children under Three

    Science.gov (United States)

    Milgrom, Peter; Huebner, Colleen; Chi, Donald

    2010-01-01

    Tooth decay and tooth loss was once the norm but public health interventions have led to major improvements for most people. Nevertheless, not all children have benefited. Dental disease in young children is unacceptably high. Tooth decay is preventable. Early childhood educators are often the first to notice the problem. Professional…

  6. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... dental words mean. The Life of a Tooth games Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | Reprints and Permissions | Privacy Statement | Terms and Conditions © 1996-2016 Academy of General Dentistry. All Rights Reserved.

  7. Life of a Tooth: A Visual Timeline

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    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Friday, July 15, 2016 About | Contact InfoBites Quick Reference ... Temporomandibular Joint Disorder Check Menstrual Calendar for Tooth Extraction Pacifiers Have Negative and Positive Effects How Do I Care for My Child's Baby Teeth? What is Orofacial ...

  8. Life of a Tooth: A Visual Timeline

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    Full Text Available ... InfoBites Quick Reference Learn more Sports and Oral Health Temporomandibular Joint Disorder Check Menstrual Calendar for Tooth ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  9. Life of a Tooth: A Visual Timeline

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    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Thursday, August 04, 2016 About | Contact InfoBites Quick Reference ... of Dental Advances How Do I Care for My Child's Baby Teeth? Headaches and Jaw Pain? Check Your Posture! Check Menstrual Calendar for Tooth Extraction Learn what ...

  10. Life of a Tooth: A Visual Timeline

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    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Saturday, June 04, 2016 About | Contact InfoBites Quick Reference ... Learn more Nutrition - Adults How Do I Care for My Child's Baby Teeth? What is Orofacial Pain? Pacifiers Have Negative and Positive Effects What is Baby Bottle Tooth ...

  11. EPR dosimetry with tooth enamel: A review

    International Nuclear Information System (INIS)

    When tooth enamel is exposed to ionizing radiation, radicals are formed, which can be detected using electron paramagnetic resonance (EPR) techniques. EPR dosimetry using tooth enamel is based on the (presumed) correlation between the intensity or amplitude of some of the radiation-induced signals with the dose absorbed in the enamel. In the present paper a critical review is given of this widely applied dosimetric method. The first part of the paper is fairly fundamental and deals with the main properties of tooth enamel and some of its model systems (e.g., synthetic apatites). Considerable attention is also paid to the numerous radiation-induced and native EPR signals and the radicals responsible for them. The relevant methods for EPR detection, identification and spectrum analyzing are reviewed from a general point of view. Finally, the needs for solid-state modelling and studies of the linearity of the dose response are investigated. The second part is devoted to the practical implementation of EPR dosimetry using enamel. It concerns specific problems of preparation of samples, their irradiation and spectrum acquisition. It also describes how the dosimetric signal intensity and dose can be retrieved from the EPR spectra. Special attention is paid to the energy dependence of the EPR response and to sources of uncertainties. Results of and problems encountered in international intercomparisons and epidemiological studies are also dealt with. In the final section the future of EPR dosimetry with tooth enamel is analyzed.

  12. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health What is Baby Bottle Tooth Decay? Headaches and ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  13. Life of a Tooth: A Visual Timeline

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    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health Check Menstrual Calendar for Tooth Extraction Pacifiers Have Negative and Positive Effects Why is Oral Health Important for Men? When Should My Child First ...

  14. Life of a Tooth: A Visual Timeline

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    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Monday, August 22, 2016 About | Contact InfoBites Quick Reference ... My Child's Baby Teeth? What is Orofacial Pain? Learn what those dental words mean. The Life of a Tooth ...

  15. Life of a Tooth: A Visual Timeline

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    Full Text Available ... a Composite Resin (White Filling)? Why is Oral Health Important for Men? How Do I Care for My Child's Baby Teeth? What is Orofacial Pain? Learn what those dental words mean. The Life of a Tooth games Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  16. Life of a Tooth: A Visual Timeline

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    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Wednesday, August 03, 2016 About | Contact InfoBites Quick Reference ... Than You Can Chew? How Do I Care for My Child's Baby Teeth? Is My Child at Risk for Early Childhood Tooth Decay? Temporomandibular Joint Disorder Learn what ...

  17. Computed tomography to quantify tooth abrasion

    Science.gov (United States)

    Kofmehl, Lukas; Schulz, Georg; Deyhle, Hans; Filippi, Andreas; Hotz, Gerhard; Berndt-Dagassan, Dorothea; Kramis, Simon; Beckmann, Felix; Müller, Bert

    2010-09-01

    Cone-beam computed tomography, also termed digital volume tomography, has become a standard technique in dentistry, allowing for fast 3D jaw imaging including denture at moderate spatial resolution. More detailed X-ray images of restricted volumes for post-mortem studies in dental anthropology are obtained by means of micro computed tomography. The present study evaluates the impact of the pipe smoking wear on teeth morphology comparing the abraded tooth with its contra-lateral counterpart. A set of 60 teeth, loose or anchored in the jaw, from 12 dentitions have been analyzed. After the two contra-lateral teeth were scanned, one dataset has been mirrored before the two datasets were registered using affine and rigid registration algorithms. Rigid registration provides three translational and three rotational parameters to maximize the overlap of two rigid bodies. For the affine registration, three scaling factors are incorporated. Within the present investigation, affine and rigid registrations yield comparable values. The restriction to the six parameters of the rigid registration is not a limitation. The differences in size and shape between the tooth and its contra-lateral counterpart generally exhibit only a few percent in the non-abraded volume, validating that the contralateral tooth is a reasonable approximation to quantify, for example, the volume loss as the result of long-term clay pipe smoking. Therefore, this approach allows quantifying the impact of the pipe abrasion on the internal tooth morphology including root canal, dentin, and enamel volumes.

  18. Life of a Tooth: A Visual Timeline

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    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health What is a Composite Resin (White Filling)? Pacifiers ... for Early Childhood Tooth Decay? Why is Oral Health Important for Men? Learn what those dental words ...

  19. Recent Approaches in Tooth Engineering Research

    Czech Academy of Sciences Publication Activity Database

    Švandová, Eva; Veselá, Barbora; Křivánek, J.; Hampl, A.; Matalová, Eva

    2014-01-01

    Roč. 60, Suppl 1 (2014), s. 21-29. ISSN 0015-5500 R&D Projects: GA ČR GAP304/11/1418; GA MZd(CZ) NT11420 Institutional support: RVO:67985904 Keywords : engineering * tooth * stem cells * culture techniques Subject RIV: EA - Cell Biology Impact factor: 1.000, year: 2014

  20. Restoration of the endodontically treated posterior tooth

    Directory of Open Access Journals (Sweden)

    Andrea Polesel

    2014-06-01

    Results and conclusions: Direct adhesive restorations, indirect bonded restorations and traditional full crown are three therapeutic options for the single posterior endodontically treated teeth. The amount of remaining sound tooth structure is the most significant factor influencing the therapeutic approach. The clinician's operative skill is a determining aspect for long-term success of adhesive inlays.

  1. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Quick Reference Learn more Oral Health and Overal Health How Do I Care for My Child's Baby Teeth? Temporomandibular Joint Disorder Pacifiers Have Negative and Positive Effects Check Menstrual Calendar for Tooth Extraction Why is Oral Health Important for Men? Learn what those dental words ...

  2. Life of a Tooth: A Visual Timeline

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    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health How Do I Care for My Child's Baby ... Menstrual Calendar for Tooth Extraction Why is Oral Health Important for Men? Learn what those dental words ...

  3. Life of a Tooth: A Visual Timeline

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    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health Are You Biting Off More Than You Can ... for Early Childhood Tooth Decay? Why is Oral Health Important for Men? Temporomandibular Joint Disorder Check Menstrual ...

  4. Life of a Tooth: A Visual Timeline

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  5. Juvenile Arrests, 2007. Juvenile Justice Bulletin

    Science.gov (United States)

    Puzzanchera, Charles

    2009-01-01

    This Bulletin summarizes 2007 juvenile crime and arrest data reported by local law enforcement agencies across the country and cited in the FBI report, "Crime in the United States 2007." The Bulletin describes the extent and nature of juvenile crime that comes to the attention of the justice system. It serves as a baseline for comparison for…

  6. Acute kidney injury after cardiac arrest

    OpenAIRE

    Tujjar, Omar; Mineo, Giulia; Dell’Anna, Antonio; Poyatos-Robles, Belen; Donadello, Katia; Scolletta, Sabino; Vincent, Jean-Louis; Taccone, Fabio Silvio

    2015-01-01

    Introduction The aim of this study was to evaluate the incidence and determinants of AKI in a large cohort of cardiac arrest patients. Methods We reviewed all patients admitted, for at least 48 hours, to our Dept. of Intensive Care after CA between January 2008 and October 2012. AKI was defined as oligo-anuria (daily urine output

  7. The Organizational Determinants of Police Arrest Decisions

    Science.gov (United States)

    Chappell, Allison T.; MacDonald, John M.; Manz, Patrick W.

    2006-01-01

    A limited amount of research has examined the relationship between characteristics of police organizations and policing styles. In particular, few studies have examined the link between organizational structures and police officer arrest decisions. Wilson's (1968) pioneering case study of police organizations suggested that individual police…

  8. Frequency and Risk Indicators of Tooth Decay among Pregnant Women in France: A Cross-Sectional Analysis

    OpenAIRE

    Vergnes, Jean-Noel; Kaminski, Monique; Lelong, Nathalie; Musset, Anne-Marie; Sixou, Michel; Nabet, Cathy; ,

    2012-01-01

    Introduction Little is known on the prevalence of tooth decay among pregnant women. Better knowledge of tooth decay risk indicators during pregnancy could help to develop follow-up protocols for women at risk, along with better prevention strategies. The aim of this study was to assess the frequency of tooth decay and the number of decayed teeth per woman in a large sample of pregnant women in France, and to study associated risk indicators. Methods A secondary cross-sectional analysis of dat...

  9. A newer simultaneous space creation, eruption, and adjacent root control spring for the management of impacted tooth

    Directory of Open Access Journals (Sweden)

    Dipti Shastri

    2014-01-01

    Full Text Available Usually, treatment of impaction includes: Welcome preparation (to create space, surgical exposure and attachment to the impacted tooth and the orthodontic guidance for the eruption of the impacted tooth. Sometimes, due to deficiency of space, creation of space for impacted tooth requires first, and space regaining efforts may require the distal movement of posterior teeth and or mesial movement of anterior teeth in the arch, but it may create some problems. To overcome the unwanted problem in this clinical situation and to reduce overall treatment duration of the patient, we have developed the Simultaneous space creation, Eruption and Adjacent root control spring to control crown as well as root movement.

  10. A refined sampling strategy for intra-tooth stable isotope analysis of mammalian enamel

    Science.gov (United States)

    Zazzo, A.; Bendrey, R.; Vella, D.; Moloney, A. P.; Monahan, F. J.; Schmidt, O.

    2012-05-01

    Serial sampling and stable isotope analysis performed along the growth axis of vertebrate tooth enamel records differences attributed to seasonal variation in diet, climate or animal movement. Because several months are required to obtain mature enamel in large mammals, modifications in the isotopic composition of environmental parameters are not instantaneously recorded, and stable isotope analysis of tooth enamel returns a time-averaged signal attenuated in its amplitude relative to the input signal. For convenience, stable isotope profiles are usually determined on the side of the tooth where enamel is thickest. Here we investigate the possibility of improving the time resolution by targeting the side of the tooth where enamel is thinnest. Observation of developing third molars (M3) in sheep shows that the tooth growth rate is not constant but decreases exponentially, while the angle between the first layer of enamel deposited and the enamel-dentine junction increases as a tooth approaches its maximal length. We also noted differences in thickness and geometry of enamel growth between the mesial side (i.e., the side facing the M2) and the buccal side (i.e., the side facing the cheek) of the M3. Carbon and oxygen isotope variations were measured along the M3 teeth from eight sheep raised under controlled conditions. Intra-tooth variability was systematically larger along the mesial side and the difference in amplitude between the two sides was proportional to the time of exposure to the input signal. Although attenuated, the mesial side records variations in the environmental signal more faithfully than the buccal side. This approach can be adapted to other mammals whose teeth show lateral variation in enamel thickness and could potentially be used as an internal check for diagenesis.

  11. The pattern of histogenesis and growth of tooth plates in larval stages of extant lungfish.

    Science.gov (United States)

    Smith, M M

    1985-06-01

    Comparison of new data obtained in this study on Protopterus aethiopicus with that published on Protopterus aethiopicus and Neoceratodus forsteri has confirmed the suggestion that the pattern of histogenesis of tooth plates in the early larval stages is very similar in the two genera. These similarities are more apparent both when a common terminology is adopted, based on a topogenic classification, and when the fundamental assumption is made that a single morphogenetic system operates for all odontodes. The model to explain the structure of all vertebrate dentitions with separate teeth in single or multiple tooth rows has been found to apply to dipnoan dentitions with fused teeth in a composite tooth plate. In this model, the epithelial invagination surrounding the margins of the tooth plate represents the dental lamina and, where this is in contact with mesenchymal cells, cell clusters (protogerms) arise. From these protogerms new odontodes (teeth) may develop if factors to inhibit differentiation are not present. Sites for initiation of odontodes become restricted to the labial margins of existing ridges on the tooth plate. Experimental studies on mammalian tooth germs are discussed and a model proposed for control of odontogenesis and histogenesis in dipnoan dentitions. Patterns of growth of hypermineralised petrodentine have been analysed and shown to depend initially on the arrangement of odontodes, and subsequently upon the ability of special cells in the pulp to generate new and wider layers of petrodentine. The initial pattern of petrodentine depends upon the position of odontodes in the forming ridges of the tooth plate. Subsequent patterns of petrodentine depend upon the extent of replacement growth beneath the tritural surface. Specialised cells, petroblasts, secrete the petrodentine within a shell of dentine. These cells differentiate from cells of the dental papilla after odontoblasts have begun to form dentine. They are regarded as a unique type of

  12. Tooth-implant connection: a review.

    Science.gov (United States)

    Hoffmann, Oliver; Zafiropoulos, Gregory-George

    2012-04-01

    The aim of this review was to assess the long-term outcomes of restorations supported by implants and natural teeth with regard to complications associated with implants, teeth, and restorations, as well as the influence on these parameters of the connector type used. A net-based search in PubMed was combined with a manual search. Clinical studies, reviews, and biomechanical studies were included. Information on survival rate, complication rate, incidence of tooth intrusion, and, where applicable, type of connector used, was retrieved from the clinical studies. Force distribution and types of connectors used were retrieved from the biomechanical study. A summary of outcomes was retrieved from the reviews. A total of 25 articles were selected for inclusion in this review, including clinical studies (15), biomechanical studies (7), and reviews (3). Implant success rates ranged from 79.5%-100%. Tooth complications occurred in 5.4%-11.8% of cases. Complications in the suprastructure were observed in 5%-90% of cases. Tooth intrusion presented in a total of 0%-66% of all cases, more often in cases with nonrigid connection (0%-66%) than in cases with rigid connection (0%-44%). Biomechanical studies show a large difference in stress distribution and in dependence on the type of connector used, with most studies demonstrating that nonrigid connectors drastically reduce stress on the suprastructure while increasing forces on supporting teeth and implants. Long-term success rates for tooth-implant connections are lower than for solely implant-supported restorations with regard to prognosis for teeth, implants, and suprastructure. Use of rigid connectors leads to more favorable clinical outcomes in terms of long-term stability, occurrence of complications, and tooth intrusion. PMID:21091344

  13. Relative cheek-tooth size in Australopithecus.

    Science.gov (United States)

    McHenry, H M

    1984-07-01

    Until the discovery of Australopithecus afarensis, cheek-tooth megadontia was unequivocally one of the defining characteristics of the australopithecine grade in human evolution along with bipedalism and small brains. This species, however, has an average postcanine area of 757 mm2, which is more like Homo habilis (759 mm2) than A. africanus (856 mm2). But what is its relative cheek-tooth size in comparison to body size? One approach to this question is to compare postcanine tooth area to estimated body weight. By this method all Australopithecus species are megadont: they have cheek teeth 1.7 to 2.3 times larger than modern hominoids of similar body size. The series from A. afarensis to A. africanus to A. robustus to A. boisei shows strong positive allometry indicating increasing megadontia through time. The series from H. habilis to H. erectus to H. sapiens shows strong negative allometry which implies a sharp reduction in the relative size of the posterior teeth. Postcanine megadontia in Australopithecus species can also be demonstrated by comparing tooth size and body size in associated skeletons: A. afarensis (represented by A.L. 288-1) has a cheek-tooth size 2.8 times larger than expected from modern hominoids; A. africanus (Sts 7) and A. robustus (TM 1517) are over twice the expected size. The evolutionary transition from the megadont condition of Australopithecus to the trend of decreasing megadontia seen in the Homo lineage may have occurred between 3.0 and 2.5 m.y. from A. afarensis to H.habilis but other evidence indicates that it is more likely to have occurred between 2.5 to 2.0 m.y. from an A. africanus-like form to H. habilis. PMID:6433716

  14. Mini Implant Facilitated Accelerated Tooth Movement in Rats

    OpenAIRE

    Cheung, Tracy Li

    2014-01-01

    Objective: Accelerated tooth movement (TM) is achieved in orthodontics via corticotomy (CY) but with invasive surgical interventions. Minimally invasive CY using mini-implant may expedite TM. In this study, we developed a rat model to evaluate orthodontic TM with mini implant-assisted CY.Methods: A split-mouth experimental design was utilized in six Sprague-Dawley rats with the CY left side and the sham right side of the maxillary 1st molars. 25g close-coiled springs were secured to both in...

  15. Inversion voltammeter definition of heavy metals in tooth pastes

    International Nuclear Information System (INIS)

    Electrochemical behaviour of some heavy metals at their combined presence is studied by voltammetric method with use of graphite content sensor. The method of determination of Hg, Pb, Cd, Cu, and Zn in the tooth pastes, based on transfer of hallmark in a solution and voltammeter diagram registration is developed. Duration of the analysis (3 collateral hallmarks) makes no more than 1.5 h. An error - 10-15 % at the contents of determined elements of the (1-5) x 10-4 %

  16. High-altitude illness induced by tooth root infection

    OpenAIRE

    FINSTERER, J.

    1999-01-01

    High-altitude illness may occur after recent pulmonary infection, but high-altitude illness after root canal therapy has not been described previously. A 44-year-old man is presented who skied to a 3333 m high peak in the Eastern Alps one day after he had undergone root canal therapy because of a tooth root infection. After 4 hours above 3000 m severe symptoms of high-altitude illness, including pulmonary oedema, developed. His condition improved after immediate descent. The next day he prese...

  17. Maternal Cardiac Arrest: A Practical and Comprehensive Review

    Directory of Open Access Journals (Sweden)

    Farida M. Jeejeebhoy

    2013-01-01

    Full Text Available Cardiac arrest during pregnancy is a dedicated chapter in the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care; however, a robust maternal cardiac arrest knowledge translation strategy and emergency response plan is not usually the focus of institutional emergency preparedness programs. Although maternal cardiac arrest is rare, the emergency department is a high-risk area for receiving pregnant women in either prearrest or full cardiac arrest. It is imperative that institutions review and update emergency response plans for a maternal arrest. This review highlights the most recent science, guidelines, and recommended implementation strategies related to a maternal arrest. The aim of this paper is to increase the understanding of the important physiological differences of, and management strategies for, a maternal cardiac arrest, as well as provide institutions with the most up-to-date literature on which they can build emergency preparedness programs for a maternal arrest.

  18. Is tooth wear in the primary dentition predictive of tooth wear in the permanent dentition? Report from a longitudinal study.

    LENUS (Irish Health Repository)

    Harding, M A

    2010-03-01

    To determine the prevalence of tooth wear in the permanent dentition of a sample of 12-year-old school children and establish whether an association exists between tooth wear recorded now and tooth wear recorded in their primary dentition at age five.

  19. A TOOTH TATTOO WITH A PURPOSE: AN INNOVATIVE APPROACH

    Directory of Open Access Journals (Sweden)

    Neetu

    2014-01-01

    Full Text Available Skin is not the only place that can be decorated with a tattoo. You can decorate your tooth with amazing tattoos. Tooth tattoos and tooth jewels have become one of the hottest fashion trends , and a very popular arrival in cosmetic dentistry. But won’t it be a boon if it had some preventive or medicinal v alue. Yes tooth tattoos can act as indicators of once illness. These tiny electronic sensors can diagnose illnesses by 'tasting' your breath. This paper is an insight into how a tooth tattoos can pick up early warning signs of sickness or infection by bact eria in people's breath.

  20. Reducing Early Childhood Tooth Decay: Strategies for State Medicaid and CHIP Dental Program Managers

    OpenAIRE

    Colin Reusch; Meg Booth; Leslie Foster

    2015-01-01

    Young children who are enrolled in Medicaid or the Children’s Health Insurance Program (CHIP) can be at risk for developing early childhood caries (ECC). ECC is a chronic bacterial infection that causes severe tooth decay and can begin to develop before baby teeth erupt.

  1. Preventing Tooth Decay: A Guide for Implementing Self-Applied Fluoride in Schools.

    Science.gov (United States)

    National Inst. of Dental Research (NIH), Bethesda, MD.

    This guidebook was developed to assist citizens in initiating programs to prevent tooth decay in young children through the use of fluoridation. It contains outlines for determining the needs of the school and community for fluoride in drinking water, and presents the various steps and activities that are necessary for developing and implementing…

  2. Locked Mouths: Tooth Loss in a Women’s Prison in Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Iris Sant’ Anna Araújo Rodrigues

    2014-01-01

    Full Text Available Background. Prisoners, in general, exhibit unsatisfactory oral conditions, especially with regard to the large number of missing teeth and with untreated caries. The aim of this study was to assess tooth loss, use of and need for prosthetic rehabilitation, and use of dental services among inmates. A cross-sectional study involving 65 inmates was developed at the Regional Women’s Prison of Campina Grande, Brazil. Data regarding sociodemographic and sentencing profile, use of dental services, dental morbidity, and self-perceived oral health impacts were investigated. Chi-square, Pearson, and Kruskal-Wallis (P<0.05 statistical tests were used. The mean tooth loss was 11.3 teeth. Significant association between tooth loss and oral health satisfaction (P=0.049, self-perceived need for dental prosthesis (P<0.001, uncomfortable teeth brushing (P=0.005, difficult speaking (P=0.002, and difficulty in performing routine tasks (P=0.025 was observed. It was observed that 29.2% of inmates were using some type of prosthesis, all deemed unsuitable for use, and 78.5% of inmates needed prosthetic rehabilitation. The oral health condition of the population studied was found to be poor, and prisoners showed significant tooth loss and need for dentures, with the aggravation of having tooth extraction as the major reason for seeking dental care.

  3. Vulnerability and the psychosocial aspects of tooth loss in old age: a Southern Brazilian study.

    Science.gov (United States)

    De Marchi, Renato J; Leal, Andréa F; Padilha, Dalva M; Brondani, Mario A

    2012-09-01

    Extensive tooth loss and edentulism can have a negative impact on the general health and quality of life of older adults. The extent to which psychological and social factors affect an individual's decision to undergo tooth extraction and mouth clearance (extraction of all teeth), and the theoretical relationships between social structure, social life and oral health can be unraveled through qualitative research. This study aimed to explore the social and psychological factors involved in tooth extraction and mouth clearance within a historical perspective among rural Southern Brazilian older adults. It is based on qualitative data gathered via a series of eight focus groups among 41 older adults. Underlying the focus group discussions of different levels of health risks and resources for prevention of disease was the concept of vulnerability. Participants' responses illustrated that tooth loss and mouth clearance were related to a lack of public dental health policies and programs, were influenced by social norms (including values pertaining to gender), and were associated with a low level of oral health knowledge. The social and program-dependent contexts of vulnerability were shown to have played a major role in the development of norms and values towards tooth extraction and mouth clearance. Vulnerability must be reduced in order to prevent disease particularly among rural populations. The influence of fatalistic beliefs about the inevitable loss of teeth with age may negatively influence the acceptance of dental treatment and predilection for oral health self-care. PMID:22870826

  4. Tooth formation - delayed or absent

    Science.gov (United States)

    ... missing teeth they never developed. Cosmetic or orthodontic dentistry can correct this problem. ... Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap ...

  5. Tooth formation - delayed or absent

    Science.gov (United States)

    ... are missing teeth they never developed. Cosmetic or orthodontic dentistry can correct this problem. Causes Specific diseases ... herein should not be used during any medical emergency or for the diagnosis or treatment of any ...

  6. Tooth mobility changes subsequent to root fractures

    DEFF Research Database (Denmark)

    Andreasen, Jens Ove; Christensen, Søren Steno Ahrensburg; Tsilingaridis, Georgios

    2012-01-01

    The purpose of this study was to analyze tooth mobility changes in root-fractured permanent teeth and relate this to type of interfragment healing (hard tissue healing (HT), interfragment healing with periodontal ligament (PDL) and nonhealing with interposition of granulation tissue (GT) because of...... pulp necrosis in the coronal fragment. Furthermore, the effect of age, location of the fracture on the root, and observation period on mobility values was analyzed. Mobility values were measured for 44 of 95 previous reported root-fractured permanent incisors. Mobility changes were measured with a...... Mühlemanns periodontometer and noninjured incisors served as controls. The mobility values represented the labial-lingual excursion of the root measured in μm when the tooth received a frontal and a palatal impact of 100 g force. In 18 cases of hard tissue healing (HT), a slightly increased mobility was seen...

  7. Design of gamma spectrometer based on the technology of virtual instrument and blue tooth communication

    International Nuclear Information System (INIS)

    The technology of virtual instruments and blue tooth communication can be applied to the design of gamma spectrometer. The hardware of system includes portable gamma spectrometer, blue tooth module and PC. The software of system includes the composed of acquisition system by the MCU and analysis system by PC. The design of acquisition system includes the design of main program, the design of liquid crystal display module, the design of keyboard module, the design of blue tooth communication module and the design of data acquisition module. The design of analysis system includes the design of serial communication module, the design of data storage module and the design of data processing module. Practice shows that the system has a user-friendly, flexible, low cost and easy to expand. It can greatly improve the analysis capabilities of energy spectrum and it is a new development direction of gamma energy spectrum. (authors)

  8. Biological approach for management of anterior tooth trauma: Triple case report

    Directory of Open Access Journals (Sweden)

    Puneet Goenka

    2011-01-01

    Full Text Available Anterior crown fractures are a common form of injury that mainly affect children and adolescents. The position of maxillary incisors and their eruptive pattern carries a significant risk for trauma. In the pre-adhesive era, fractured teeth needed to be restored either with pin-retained inlays or cast restorations that sacrificed healthy tooth structure, and were a challenge for clinicians to match with adjacent teeth. The development of adhesive dentistry has allowed dentists to use the patient′s own fragment to restore the fractured tooth. Three cases are presented here with complicated crown fracture of maxillary central incisors; the reattachment of the fractured tooth segment in these cases has been performed using different combinations of techniques, viz. simple reattachment, circumferential bevel and internal dentinal groove.

  9. Biological approach for management of anterior tooth trauma: Triple case report

    Directory of Open Access Journals (Sweden)

    Goenka P

    2010-09-01

    Full Text Available Anterior crown fractures are a common form of injury that mainly affect children and adolescents. The position of maxillary incisors and their eruptive pattern carries a significant risk for trauma. In the pre-adhesive era, fractured teeth needed to be restored either with pin-retained inlays or cast restorations that sacrificed healthy tooth structure and were a challenge for clinicians to match with adjacent teeth. The development of adhesive dentistry has allowed dentists to use the patient′s own fragment to restore the fractured tooth. Three cases are presented here with complicated crown fracture of maxillary central incisors; the reattachment of the fractured tooth segment in this case has been performed using different combinations of techniques, viz. simple reattachment, circumferential bevel and internal dentinal groove.

  10. Enamel alteration following tooth bleaching and remineralization.

    Science.gov (United States)

    Coceska, Emilija; Gjorgievska, Elizabeta; Coleman, Nichola J; Gabric, Dragana; Slipper, Ian J; Stevanovic, Marija; Nicholson, John W

    2016-06-01

    The purpose of this study was to compare the effects of professional tooth whitening agents containing highly concentrated hydrogen peroxide (with and without laser activation), on the enamel surface; and the potential of four different toothpastes to remineralize any alterations. The study was performed on 50 human molars, divided in two groups: treated with Opalescence(®) Boost and Mirawhite(®) Laser Bleaching. Furthermore, each group was divided into five subgroups, a control one and 4 subgroups remineralized with: Mirasensitive(®) hap+, Mirawhite(®) Gelleѐ, GC Tooth Mousse™ and Mirafluor(®) C. The samples were analysed by SEM/3D-SEM-micrographs, SEM/EDX-qualitative analysis and SEM/EDX-semiquantitative analysis. The microphotographs show that both types of bleaching cause alterations: emphasized perikymata, erosions, loss of interprizmatic substance; the laser treatment is more aggressive and loss of integrity of the enamel is determined by shearing off the enamel rods. In all samples undergoing remineralization deposits were observed, those of toothpastes based on calcium phosphate technologies seem to merge with each other and cover almost the entire surface of the enamel. Loss of integrity and minerals were detected only in the line-scans of the sample remineralized with GC Tooth Mousse™. The semiquantitative EDX analysis of individual elements in the surface layer of the enamel indicates that during tooth-bleaching with HP statistically significant loss of Na and Mg occurs, whereas the bleaching in combination with a laser leads to statistically significant loss of Ca and P. The results undoubtedly confirm that teeth whitening procedures lead to enamel alterations. In this context, it must be noted that laser bleaching is more aggressive for dental substances. However, these changes are reversible and can be repaired by application of remineralization toothpastes. PMID:27197087

  11. EPR TOOTH DOSIMETRY OF SNTS AREA INHABITANTS

    OpenAIRE

    Sholom, Sergey; Desrosiers, Marc; Bouville, André; Luckyanov, Nicholas; Chumak, Vadim; Simon, Steven L.

    2007-01-01

    The determination of external dose to teeth of inhabitants of settlements near the Semipalatinsk Nuclear Test Site (SNTS) was conducted using the EPR dosimetry technique to assess radiation doses associated with exposure to radioactive fallout from the test site. In this study, tooth doses have been reconstructed for 103 persons with all studied teeth having been formed before the first nuclear test in 1949. Doses above those received from natural background radiation, termed “accident doses”...

  12. Ectopic Premolar Tooth in the Sigmoid Notch

    Science.gov (United States)

    Akgül, H. M.; Bayrakdar, I. S.

    2016-01-01

    Impaction of a mandibular premolar is relatively uncommon. Ectopic placement is more unusual and there has been no discussion in the literature of an ectopic mandibular premolar in the coronoid process. In this case report, we present an impacted ectopic mandibular permanent premolar in the sigmoid notch (incisura mandibulae) region. Etiology of the tooth and treatment options are discussed and illustrated by Cone Beam Computed Tomography (CBCT) images.

  13. Tooth loss and obstructive sleep apnoea

    OpenAIRE

    Gai Valerio; Pera Paolo; Erovigni Francesco; Graziano Alessandra; Arienti Andrea; Brussino Luisa; Cicolin Alessandro; Bucca Caterina; Mutani Roberto; Preti Giulio; Rolla Giovanni; Carossa Stefano

    2006-01-01

    Abstract Background Complete tooth loss (edentulism) produces anatomical changes that may impair upper airway size and function. The aim of this study was to evaluate whether edentulism favours the occurrence of obstructive sleep apnoea (OSA). Methods Polysomnography was performed in 48 edentulous subjects on two consecutive nights, one slept with and the other without dentures. Upper airway size was assessed by cephalometry and by recording forced mid-inspiratory airflow rate (FIF50). Exhale...

  14. American Heart Association Response to the 2015 Institute of Medicine Report on Strategies to Improve Cardiac Arrest Survival.

    Science.gov (United States)

    Neumar, Robert W; Eigel, Brian; Callaway, Clifton W; Estes, N A Mark; Jollis, James G; Kleinman, Monica E; Morrison, Laurie J; Peberdy, Mary Ann; Rabinstein, Alejandro; Rea, Thomas D; Sendelbach, Sue

    2015-09-15

    The American Heart Association (AHA) commends the recently released Institute of Medicine (IOM) report, Strategies to Improve Cardiac Arrest Survival: A Time to Act (2015). The AHA recognizes the unique opportunity created by the report to meaningfully advance the objectives of improving outcomes for sudden cardiac arrest. For decades, the AHA has focused on the goal of reducing morbidity and mortality from cardiovascular disease though robust support of basic, translational, clinical, and population research. The AHA also has developed a rigorous process using the best available evidence to develop scientific, advisory, and guideline documents. These core activities of development and dissemination of scientific evidence have served as the foundation for a broad range of advocacy initiatives and programs that serve as a foundation for advancing the AHA and IOM goal of improving cardiac arrest outcomes. In response to the call to action in the IOM report, the AHA is announcing 4 new commitments to increase cardiac arrest survival: (1) The AHA will provide up to $5 million in funding over 5 years to incentivize resuscitation data interoperability; (2) the AHA will actively pursue philanthropic support for local and regional implementation opportunities to increase cardiac arrest survival by improving out-of-hospital and in-hospital systems of care; (3) the AHA will actively pursue philanthropic support to launch an AHA resuscitation research network; and (4) the AHA will cosponsor a National Cardiac Arrest Summit to facilitate the creation of a national cardiac arrest collaborative that will unify the field and identify common goals to improve survival. In addition to the AHA's historic and ongoing commitment to improving cardiac arrest care and outcomes, these new initiatives are responsive to each of the IOM recommendations and demonstrate the AHA's leadership in the field. However, successful implementation of the IOM recommendations will require a timely

  15. Pediatric Cardiac Arrest Due to Trauma.

    Science.gov (United States)

    Kjellemo, Hugo; Hansen, Andreas E; Øines, Dennis A; Nilsen, Thor O; Wik, Lars

    2016-01-01

    Survival from pediatric cardiac arrest due to trauma has been reported to be 0.0%-8.8%. Some argue that resuscitation efforts in the case of trauma-related cardiac arrests are futile. We describe a successful outcome in the case of a child who suffered cardiac arrest caused by external traumatic airway obstruction. Our case illustrates how to deal with pediatric traumatic cardiac arrests in an out-of-hospital environment. It also illustrates how good clinical treatment in these situations may be supported by correct treatment after hospital admission when it is impossible to ventilate the patient to provide sufficient oxygen delivery to vital organs. This case relates to a lifeless child of 3-5 years, blue, and trapped by an electrically operated garage door. The first ambulance arrived to find several men trying to bend the frame and the door apart in order to extricate the child, who was hanging in the air with head and neck squeezed between the horizontally-moving garage door and the vertical door frame. One paramedic found a car jack and used it to push the door and the frame apart, allowing the lifeless child to be extricated. Basic life support was then initiated. Intubation was performed by the anesthesiologist without drugs. With FiO2 1.0 the first documented SaO2 was <50%. Restoration of Spontaneous Circulation was achieved after thirty minutes, and she was transported to the hospital. After a few hours she was put on venous-arterial ECMO for 5.5 days and discharged home after two months. Outpatient examinations during the rest of 2013 were positive, and the child found not to be suffering from any injuries, either physical or mental. The last follow-up in October 2014 demonstrated she had made a 100% recovery and she started school in August 2014. PMID:26930137

  16. Nuclear reactor melt arrest and coolability device

    Energy Technology Data Exchange (ETDEWEB)

    Theofanous, Theo G.; Dinh, Nam Truc; Wachowiak, Richard M.

    2016-06-14

    Example embodiments provide a Basemat-Internal Melt Arrest and Coolability device (BiMAC) that offers improved spatial and mechanical characteristics for use in damage prevention and risk mitigation in accident scenarios. Example embodiments may include a BiMAC having an inclination of less than 10-degrees from the basemat floor and/or coolant channels of less than 4 inches in diameter, while maintaining minimum safety margins required by the Nuclear Regulatory Commission.

  17. Inactivation of IL11 signaling causes craniosynostosis, delayed tooth eruption, and supernumerary teeth

    DEFF Research Database (Denmark)

    Nieminen, Pekka; Morgan, Neil V; Fenwick, Aimée L; Parmanen, Satu; Veistinen, Lotta; Mikkola, Marja L; van der Spek, Peter J; Giraud, Andrew; Judd, Louise; Arte, Sirpa; Brueton, Louise A; Wall, Steven A; Mathijssen, Irene M J; Maher, Eamonn R; Wilkie, Andrew O M; Kreiborg, Sven; Thesleff, Irma

    2011-01-01

    Craniosynostosis and supernumerary teeth most often occur as isolated developmental anomalies, but they are also separately manifested in several malformation syndromes. Here, we describe a human syndrome featuring craniosynostosis, maxillary hypoplasia, delayed tooth eruption, and supernumerary...... remodeling of limb bones has been previously described. We conclude that IL11 signaling is essential for the normal development of craniofacial bones and teeth and that its function is to restrict suture fusion and tooth number. The results open up the possibility of modulation of IL11 signaling for the...

  18. Peptide-induced de novo bone formation after tooth extraction prevents alveolar bone loss in a murine tooth extraction model.

    Science.gov (United States)

    Arai, Yuki; Aoki, Kazuhiro; Shimizu, Yasuhiro; Tabata, Yasuhiko; Ono, Takashi; Murali, Ramachandran; Mise-Omata, Setsuko; Wakabayashi, Noriyuki

    2016-07-01

    Tooth extraction causes bone resorption of the alveolar bone volume. Although recombinant human bone morphogenetic protein 2 (rhBMP-2) markedly promotes de novo bone formation after tooth extraction, the application of high-dose rhBMP-2 may induce side effects, such as swelling, seroma, and an increased cancer risk. Therefore, reduction of the necessary dose of rhBMP-2 which can still obtain sufficient bone mass is necessary by developing a new osteogenic reagent. Recently, we showed that the systemic administration of OP3-4 peptide, which was originally designed as a bone resorption inhibitor, had osteogenic ability both in vitro and in vivo. This study evaluated the ability of the local application of OP3-4 peptide to promote bone formation in a murine tooth extraction model with a very low-dose of BMP. The mandibular incisor was extracted from 10-week-old C57BL6/J male mice and a gelatin hydrogel containing rhBMP-2 with or without OP3-4 peptide (BMP/OP3-4) was applied to the socket of the incisor. Bone formation inside the socket was examined radiologically and histologically at 21 days after the extraction. The BMP/OP3-4-group showed significant bone formation inside the mandibular extraction socket compared to the gelatin-hydrogel-carrier-control group or rhBMP-2-applied group. The BMP/OP3-4-applied mice showed a lower reduction of alveolar bone and fewer osteoclast numbers, suggesting that the newly formed bone inside the socket may prevent resorption of the cortical bone around the extraction socket. Our data revealed that OP3-4 peptide promotes BMP-mediated bone formation inside the extraction socket of mandibular bone, resulting in preservation from the loss of alveolar bone. PMID:27118173

  19. Tooth wear: the view of the anthropologist.

    Science.gov (United States)

    Kaidonis, John A

    2008-03-01

    Anthropologists have for many years considered human tooth wear a normal physiological phenomenon where teeth, although worn, remain functional throughout life. Wear was considered pathological only if pulpal exposure or premature tooth loss occurred. In addition, adaptive changes to the stomatognathic system in response to wear have been reported including continual eruption, the widening of the masticatory cycle, remodelling of the temporomandibular joint and the shortening of the dental arches from tooth migration. Comparative studies of many different species have also documented these physiological processes supporting the idea of perpetual change over time. In particular, differential wear between enamel and dentine was considered a physiological process relating to the evolution of the form and function of teeth. Although evidence of attrition and abrasion has been known to exist among hunter-gatherer populations for many thousands of years, the prevalence of erosion in such early populations seems insignificant. In particular, non-carious cervical lesions to date have not been observed within these populations and therefore should be viewed as 'modern-day' pathology. Extrapolating this anthropological perspective to the clinical setting has merits, particularly in the prevention of pre-mature unnecessary treatment. PMID:17938977

  20. Anthropology, tooth wear, and occlusion ab origine.

    Science.gov (United States)

    Young, W G

    1998-11-01

    The purpose of this essay is to emphasize that anthropology, the study of man in his environments, is a potent tool for scientific discovery and inspiration in dental science. It attempts to capture flashes of creative anthropological insight which have illuminated studies of tooth wear and occlusion in the past. While it documents contributions, understandings, and misunderstandings from Australian and New Zealand dentists, it is not a hagiography. The real saint of this essay is the Australian aborigine. For when men and women are understood in their environments, much is learned from them which challenges preconceptions of our dental science culture. The essay concludes that new, contemporary Australian culture needs to be studied by anthropological approaches if we are to understand how dental erosion is exacerbating tooth wear and damaging the occlusions of contemporary Australians. Much remains to be discovered about contemporary lifestyles, habits, and diets that lead to dental erosion, the principal cause of contemporary tooth wear in this part of the world. PMID:9823723

  1. Digital Computer Matching of Tooth Color

    Directory of Open Access Journals (Sweden)

    Won-suk Oh

    2010-06-01

    Full Text Available This study aimed to determine the validity of the digital photocolorimetric (PCM method in matching the color of human teeth. First, two Vitapan Classical shade guides, each containing 16 shade guide teeth, were visually shade matched, and digital photographs of each three pair of shade guide teeth were taken in a color matching booth. Secondly, visual shade matching of the upper central incisors of 48 subjects was performed by two prosthodontists independently in a chair, using the Vitapan Classical shade guide. The three closest shade guide teeth were visually selected and ranked in order of preference, for which digital photographs were taken under ceiling daylight-corrected fluorescent lighting. All digital images were analyzed on a computer screen using software to calculate the color difference between the reference tooth and other teeth in the same digital image. The percent color matching for the shade guide teeth and human teeth was 88% and 75%, respectively. There was no statistically significant difference in matching the tooth color between the shade guide teeth and human teeth. The digital PCM method is valid for the range of human teeth based on the Vitapan Classical shade guide. This method enhances communication with the laboratory personnel in matching the tooth color.

  2. Bodybuilding supplementation and tooth decay.

    Science.gov (United States)

    Ali, M S; Batley, H; Ahmed, F

    2015-07-10

    Supplementation is a key component in bodybuilding and is increasingly being used by amateur weight lifters and enthusiasts to build their ideal bodies. Bodybuilding supplements are advertised to provide nutrients needed to help optimise muscle building but they can contain high amounts of sugar. Supplement users are consuming these products, while not being aware of their high sugar content, putting them at a higher risk of developing dental caries. It is important for dental professionals to recognise the increased risk for supplement users and to raise awareness, provide appropriate preventative advice and be knowledgeable of alternative products to help bodybuilders reach their goals, without increasing the risk of dental caries. PMID:26159983

  3. Osteitis pubis ameliorated after tooth extraction: a case report.

    Science.gov (United States)

    Fukushi, Jun-ichi; Nakashima, Yasuharu; Iwamoto, Yukihide

    2013-03-01

    Osteitis pubis is a non-infective inflammation of the symphysis pubis, which is known to be associated with trauma, athletic exertion, urological or gynecological surgery, or with rheumatic conditions such as seronegative spondyloarthropathies. In this report, we describe a case of osteitis pubis whose symptoms were completely ameliorated following tooth extraction attributable to periodontitis. A 57-year-old female patient developed osteitis pubis, presenting with pain in the groin area with an elevated Creactive protein (CRP; 4.4 mg/dl) and radiological erosive changes in symphysis pubis. Prednisolone (5 mg/day) and etodolac were prescribed, but the patient's symptoms improved only partially and remained persistent. One year from the patient's first visit, three teeth were extracted due to severe chronic periodontitis, which she had been suffering from for years. Soon after the above tooth extraction, her symptoms appeared completely resolved, and the patient's CRP was decreased to nearly normal levels in 4 weeks. Human leukocyte antigen (HLA)-typing analysis revealed a positive result for HLA-A11, A24, and B54. Because HLA-B54 cross-reacts with HLA-B27, the patient's osteitis pubis was considered to be a form of reactive arthritis associated with periodontitis. PMID:23599946

  4. Head Start Combats Baby Bottle Tooth Decay Among Native American Families.

    Science.gov (United States)

    Phillips, Margaret G.; Stubbs, Phyllis E.

    1987-01-01

    Presents current developments concerning nursing bottle caries--"baby bottle tooth decay"--and spotlights a program funded by Head Start to reduce the prevalence of these painful and disfiguring, but preventable, children's dental diseases among American Indians and Alaska Native families. (Author/BB)

  5. EQUIDISTANT TOOTH GENERATION ON NONCYLINDRICAL SURFACES FOR TWO-PARAMETER GEARING

    Directory of Open Access Journals (Sweden)

    Yuriy GUTSALENKO,

    2011-11-01

    Full Text Available The questions of design research of noncylindrical tooth surfaces for two-parameter gearing on example of bevel gears with constant normal pitch forgearing variators are been considered. Engineering is based on the special applied development of the mathematical theory of multiparametric mappings of space.

  6. Apoptosis distribution in the first molar tooth germ of the field vole (Microtus agrestis)

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Witter, Kirsti; Míšek, Ivan

    2004-01-01

    Roč. 36, - (2004), s. 361-367. ISSN 0040-8166 R&D Projects: GA ČR GP204/02/P112 Institutional research plan: CEZ:AV0Z5045916 Keywords : apoptosis * tooth development * DA fragmentation Subject RIV: EA - Cell Biology Impact factor: 0.937, year: 2004

  7. Reversible cryo-arrest for imaging molecules in living cells at high spatial resolution.

    Science.gov (United States)

    Masip, Martin E; Huebinger, Jan; Christmann, Jens; Sabet, Ola; Wehner, Frank; Konitsiotis, Antonios; Fuhr, Günther R; Bastiaens, Philippe I H

    2016-08-01

    The dynamics of molecules in living cells hampers precise imaging of molecular patterns by functional and super-resolution microscopy. We developed a method that circumvents lethal chemical fixation and allows on-stage cryo-arrest for consecutive imaging of molecular patterns within the same living, but arrested, cells. The reversibility of consecutive cryo-arrests was demonstrated by the high survival rate of different cell lines and by intact growth factor signaling that was not perturbed by stress response. Reversible cryo-arrest was applied to study the evolution of ligand-induced receptor tyrosine kinase activation at different scales. The nanoscale clustering of epidermal growth factor receptor (EGFR) in the plasma membrane was assessed by single-molecule localization microscopy, and endosomal microscale activity patterns of ephrin receptor A2 (EphA2) were assessed by fluorescence lifetime imaging microscopy. Reversible cryo-arrest allows the precise determination of molecular patterns while conserving the dynamic capabilities of living cells. PMID:27400419

  8. The Association Between childhood Obesity and Tooth Eruption

    OpenAIRE

    Must, Aviva; Phillips, Sarah M.; Tybor, David J.; Lividini, Keith; Hayes, Catherine

    2012-01-01

    Obesity is a growth-promoting process as evidenced by its effect on the timing of puberty. Although studies are limited, obesity has been shown to affect the timing of tooth eruption. Both the timing and sequence of tooth eruption are important to overall oral health. The purpose of this study was to examine the association between obesity and tooth eruption. Data were combined from three consecutive cycles (2001–2006) of the National Health and Nutrition Examination Survey (NHANES) and analy...

  9. Sonosurgery for atraumatic tooth extraction: a clinical report.

    Science.gov (United States)

    Papadimitriou, Dimitrios E V; Geminiani, Alessandro; Zahavi, Thomas; Ercoli, Carlo

    2012-12-01

    The preservation of an intact labial plate during tooth extraction is a critical determinant of whether an immediate implant can be placed and is also an important predictor of the esthetic result. The purpose of this clinical report was to present a method for atraumatic tooth extraction by using an air-driven sonic instrument with specially designed inserts. This surgical technique provides the clinician with an efficient method for atraumatic tooth extraction and preservation of an intact labial plate. PMID:23217465

  10. Hair keratin mutations in tooth enamel increase dental decay risk

    OpenAIRE

    Duverger, Olivier; Ohara, Takahiro; Shaffer, John R.; Donahue, Danielle; Zerfas, Patricia; Dullnig, Andrew; Crecelius, Christopher; Beniash, Elia; Marazita, Mary L; Morasso, Maria I.

    2014-01-01

    Tooth enamel is the hardest substance in the human body and has a unique combination of hardness and fracture toughness that protects teeth from dental caries, the most common chronic disease worldwide. In addition to a high mineral content, tooth enamel comprises organic material that is important for mechanical performance and influences the initiation and progression of caries; however, the protein composition of tooth enamel has not been fully characterized. Here, we determined that epith...

  11. Protection and Reinforcement of Tooth Structures by Dental Coating Materials

    OpenAIRE

    Toru Nikaido; Rena Takahashi; Meu Ariyoshi; Junji Tagami; Alireza Sadr

    2012-01-01

    It has been proposed that a resin coating can serve as a means to protect dental structure after preparation of the tooth for indirect restorations, sealing the exposed dentin. The resin coating is applied on the cut surfaces immediately after tooth preparation and before making an impression by assembling a dentin bonding system and a flowable composite. Resin coatings minimize pulp irritation and improve the bond strength between a resin cement and tooth when bonding the restoration to toot...

  12. A theropod tooth from the Late Triassic of southern Africa

    Indian Academy of Sciences (India)

    Sanghamitra Ray; Anusuya Chinsamy

    2002-06-01

    An isolated, large recurved and finely serrated tooth found associated with the prosauropod Euskelosaurus from the Late Triassic part of the Elliot Formation is described here. It is compared to the Triassic thecodonts and carnivorous dinosaurs and its possible affinity is discussed. The tooth possibly belongs to a basal theropod and shows some features similar to the allosauroids. This tooth is of significance, as dinosaur remains except for some footprints and trackways, are poorly known in the Late Triassic horizons of southern Africa.

  13. Esthetic Management of an Anterior Avulsed Tooth: A Case Report

    OpenAIRE

    AR, Prabhakar; Sugandhan,; KB, Roopa; Gulati, Akanksha

    2009-01-01

    Avulsion and luxation account for up to 16% of all traumatic injuries in the permanent dentition and 7.2% of injuries in the primary dentition. A range of treatment options are available that can help conserve the tooth after a traumatic episode. There are, however, occasions where loss of the traumatized tooth is inevitable with special regard to avulsion injuries. replantation of teeth having doubtful long-term prognosis. Following the traumatic loss of an anterior tooth it is important tha...

  14. A TOOTH TATTOO WITH A PURPOSE: AN INNOVATIVE APPROACH

    OpenAIRE

    Neetu,; Anuroop; Prasant; Ashishkumar K; Fareedi Mukram

    2014-01-01

    Skin is not the only place that can be decorated with a tattoo. You can decorate your tooth with amazing tattoos. Tooth tattoos and tooth jewels have become one of the hottest fashion trends , and a very popular arrival in cosmetic dentistry. But won’t it be a boon if it had some preventive or medicinal v alue. Yes tooth tattoos can act as indicators of once illness. These tiny electronic sensors can diagnose illnesses by 'tasting' your breath. This paper is an i...

  15. [Interproximal tooth cleansing of abutment teeth and pontic design].

    Science.gov (United States)

    Kocher, T; Plagmann, H C; Engelsmann, U; Schlüter, R

    1990-03-01

    This clinical study was an attempt to find out if a patient's home care plaque control at his or her abutment tooth is more effectively enhanced by a modified ridge lap or a hygienic pontic design. Oral hygiene was performed either with a tooth brush alone or in combination with an interdental brush. We found that the effectivity of interproximal toothcleaning was not influenced by the pontic design and that only interdental brushes permit a good plaque control at the proximal area of the abutment tooth. This implies that "self cleansing" is non-existent in these tooth areas. PMID:2257819

  16. Tooth-marked small theropod bone: an extremely rare trace

    DEFF Research Database (Denmark)

    Jacobsen, Aase Roland

    2001-01-01

    Tooth-marked dinosaur bones provide insight into feeding behaviours and biting strategies of theropod dinosaurs. The majority of theropod tooth marks reported to date have been found on herbivorous dinosaur bones, although some tyrannosaurid bones with tooth marks have also been reported. In 1988...... partial skeleton of the dromaeosaurid Saurornitholestes was collected from southern Alberta, Canada, that bore marks on one dentary. The location and morphology of the tooth marks suggests that a theropod (possible a juvenile tyrannosaurid) included a Saurornitholestes in its diet....

  17. Experience with bretylium tosylate by a hospital cardiac arrest team.

    Science.gov (United States)

    Holder, D A; Sniderman, A D; Fraser, G; Fallen, E L

    1977-03-01

    The effect of bretylium tosylate (BT) was determined in 27 consecutive cases of resistant ventricular fibrillation (VF) encountered by a hospital cardiac arrest team. The VF was sustained and completely resistant to multiple injections of lidocaine, sequential DC shocks at 400 watt-sec and one or a combination of intravenous propranolol, diphenylhydantoin or procainamide. Following 30 min of sustained cardiac massage, BT (5 mg/kg i.v.) was administered. In 20 patients, VF was terminated within 9-12 min after DC shock. Eight of these patients failed to recover while 12 (44%) of all patients resuscitated survived to be discharged from hospital. Eleven out of 20 (55%) of all patients who had a cardiac arrest outside the CCU were survivors; only one out of seven in the CCU were successfully resuscitated. While receiving maintanance BT post-resuscitation (5 mg/kg i.m. q 8-12 hrs x 48 hrs), half the patients developed hypotension and three required vasopressors and/or fluid replacement. The data indicate that BT is a useful agent in patients with sustained VF refractory to repeated lidocaine injections, some other antiarrhythmic agents, and multiple DC shocks. PMID:837490

  18. The G2-arrest in the BALB/c embryo: relationship with transcription

    International Nuclear Information System (INIS)

    One-cell embryos of the BALB/c strain are extremely sensitive to the radiation-induced G2-arrest. Earlier studies suggested that the period of sensitivity to this effect is restricted to the S phase. This point was now studied more in details, using very synchronous embryonic populations and a higher dose of X-rays. The sensitivity towards radiation-induced G2-arrest was also investigated at the two immediately following stages of preimplantation development, i.e. the two-cell and the four-cell stages. (authors)

  19. Impact of diet on tooth erosion.

    Science.gov (United States)

    Richards, Derek

    2016-06-01

    Data sourcesPubMed, Web of Science, Scopus, Science Direct, EBSHost, Scientific Electronic Library online (SciELO).Study selectionPopulation-based cross-sectional and longitudinal studies assessing tooth erosion and diet, conducted in children and adolescents between eight and 19 years reporting on the permanent dentition were considered.Data extraction and synthesisStudies were selected independently by two reviewers and standard data items extracted. Study quality was assessed using the STROBE (Strengthening the Reporting of Observational studies in Epidemiology) statement and Newcastle-Ottawa Quality Assessment Scale (NOS). The pooled effect of dietary habits on tooth erosion occurrence was calculated using a fixed and a random model (OR and 95%CI).ResultsThirteen studies involving a total of 16,661 children were included. Eleven of the studies were cross-sectional and two longitudinal. Dietary habits data were mainly obtained from brief dietary assessments (69.2%) with food amount (weighed or estimated) and food frequency questionnaires used less commonly (15.4%). Most dietary assessments were self-administered (84.6%), assessed diet on a single occasion (61.5%) and required recalls of a week or more days or usual behaviours (46.2%). Meta-analyses were carried out for carbonated/soft drinks, sports drinks, milk-based drinks, yogurt, confectionery and snacks and acidic natural fruit drinks. Higher consumption of carbonated drinks or acid snacks/sweets and for acid fruit juices increased the odds for tooth erosion, while higher intake of milk and yogurt reduced the odds of erosion (see table).ConclusionsThe evidence indicated that some dietary habits (soft drinks, acidic snacks/sweets and acidic fruit juices) increased the odds for erosion occurrence, while milk or yogurt produced a protective effect. Methodological issues were shown to partly explain the heterogeneity of the data for some dietary products. PMID:27339233

  20. Forensic Identification Based on Tooth Material

    Directory of Open Access Journals (Sweden)

    Elza Ibrahim Auerkari

    2015-10-01

    Full Text Available Human teeth are the most robust and stable parts of the body, providing biological clue material for forensic purposes even when most of the oter means of identifcation have been seriously affected by adverse environmental conditions. In particular blood grouping, isozymes, serum proteins and DNA polymorhphisms can be detected from teeth that protect these identification markers in addition to the traditional dental records. While in general the value of traditional dental records in the forensic work is decreasing eg due to mproved dental care, the newer means of identification from tooth material provide considerable promise for effective identification in difficult cases.The DNA analysis from tooth material has been shown to ba a viable route in forensic analysis, when other material for such an analysis is unusable. However in most cases useful biologic material other than teeth is abailable, and then DNA analysis can be made from other tissue with less effort than by using teeth. Also, in cases with lacking other tissue, blood grouping, isozymes and serum proteins may provide cheaper inherited combinations of blood grouping, isozymes and serum proteins can be treated similary to polymorphic DNA loci as independent markers, their identification can be managed if the false positives and negatives in analysis can be minimmised, and the corresponding frequencies of occurrence are known.It was the purpose of the present work to review the methods of forensic identification from tooth material, based on analysis of blood grouping, isozymes and serum proteins. It appears that such a combined analysis provides a robust method for forensic purposes. Nevertheless, for efficient identification it is recommended that as many (multiple forensic methods as possible are combined, so that faster and cheaper methods such as imminent medical forensics are used first, and more thorough analysis is used to support and complement these methods.

  1. The regulation of tooth morphogenesis is associated with epithelial cell proliferation and the expression of Sonic hedgehog through epithelial-mesenchymal interactions

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Kentaro; Murofushi, Mayumi [Faculty of Industrial Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Nakao, Kazuhisa; Morita, Ritsuko [Research Institute for Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Ogawa, Miho [Research Institute for Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Organ Technologies Inc., Tokyo 101-0048 (Japan); Tsuji, Takashi, E-mail: t-tsuji@rs.noda.tus.ac.jp [Faculty of Industrial Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Research Institute for Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan); Organ Technologies Inc., Tokyo 101-0048 (Japan)

    2011-02-18

    Research highlights: {yields} Bioengineered teeth regulated the contact area of epithelium and mesenchyme. {yields} The crown width is regulated by the contact area of the epithelium and mesenchyme. {yields} This regulation is associated with cell proliferation and Sonic hedgehog expression. {yields} The cusp number is correlated with the crown width of the bioengineered tooth. {yields} Cell proliferation and Shh expression areas regulate the tooth morphogenesis. -- Abstract: Ectodermal organs, such as the tooth, salivary gland, hair, and mammary gland, develop through reciprocal epithelial-mesenchymal interactions. Tooth morphologies are defined by the crown width and tooth length (macro-morphologies), and by the number and locations of the cusp and roots (micro-morphologies). In our current study, we report that the crown width of a bioengineered molar tooth, which was reconstructed using dissociated epithelial and mesenchymal cells via an organ germ method, can be regulated by the contact area between epithelial and mesenchymal cell layers. We further show that this is associated with cell proliferation and Sonic hedgehog (Shh) expression in the inner enamel epithelium after the germ stage has formed a secondary enamel knot. We also demonstrate that the cusp number is significantly correlated with the crown width of the bioengineered tooth. These findings suggest that the tooth micro-morphology, i.e. the cusp formation, is regulated after the tooth width, or macro-morphology, is determined. These findings also suggest that the spatiotemporal patterning of cell proliferation and the Shh expression areas in the epithelium regulate the crown width and cusp formation of the developing tooth.

  2. Abulia following an episode of cardiac arrest.

    Science.gov (United States)

    Naik, Vismay Dinesh

    2015-01-01

    The word 'abulia' means a lack of will, initiative or drive. The symptoms of abulia include lack of spontaneous action and speech, reduced emotional responsiveness and social interaction, poor attention and easy distractibility. These symptoms are independent of reduced levels of consciousness or cognitive impairment. We describe a case of a socially active 72-year-old female patient who presented with symptoms of abulia which may have occurred due to damage of the frontosubcortical circuits following an episode of cardiac arrest. The patient's symptoms improved dramatically following treatment with bromocriptine. PMID:26135487

  3. Comparison of the effect of thermal stresses on tooth-colored posts, cores and tooth structures by finite element analysis

    OpenAIRE

    Egilmez, Ferhan; Nalbant, Levent

    2012-01-01

    Objectives: The aims of this study were to analyze the influence of cold heat flow in all ceramic crown material, composite core, zirconium and glass fiber reinforced composite post materials, resin based luting cement and root dentin; and to compare these two tooth-colored post systems about their temperature and thermal stress distributions. Materials and Methods: A 3-dimesional finite element model of maxillary left canine tooth was constructed. All ceramic crown, composite core, tooth den...

  4. Sublingual Microcirculation is Impaired in Post-cardiac Arrest Patients

    DEFF Research Database (Denmark)

    G. Omar, Yasser; Massey, Michael; Wiuff Andersen, Lars; A. Giberson, Tyler; Berg, Katherine; N. Cocchi, Michael; I. Shapiro, Nathan; W. Donnino, Michael

    2013-01-01

    markers in the post-cardiac arrest state. METHODS: We prospectively evaluated the sublingual microcirculation in post-cardiac arrest patients, severe sepsis/septic shock patients, and healthy control patients using Sidestream Darkfield microscopy. Microcirculatory flow was assessed using the...... microcirculation flow index (MFI) at 6 and 24h in the cardiac arrest patients, and within 6h of emergency department admission in the sepsis and control patients. RESULTS: We evaluated 30 post-cardiac arrest patients, 16 severe sepsis/septic shock patients, and 9 healthy control patients. Sublingual...... microcirculatory blood flow was significantly impaired in post-cardiac arrest patients at 6h (MFI 2.6 [IQR: 2-2.9]) and 24h (2.7 [IQR: 2.3-2.9]) compared to controls (3.0 [IQR: 2.9-3.0]; p<0.01 and 0.02, respectively). After adjustment for initial APACHE II score, post-cardiac arrest patients had significantly...

  5. A case of thyroid storm with cardiac arrest

    Directory of Open Access Journals (Sweden)

    Nakashima Y

    2014-05-01

    Full Text Available Yutaka Nakashima,1 Tsuneaki Kenzaka,2 Masanobu Okayama,3 Eiji Kajii31Department for Support of Rural Medicine, Yamaguchi Grand Medical Center, 2Division of General Medicine, Center for Community Medicine, Jichi Medical University School of Medicine, Shimotsuke, Japan; 3Division of Community and Family Medicine, Center for Community Medicine, Jichi Medical University School of Medicine, Shimotsuke, JapanAbstract: A 23-year-old man became unconscious while jogging. He immediately received basic life support from a bystander and was transported to our hospital. On arrival, his spontaneous circulation had returned from a state of ventricular fibrillation and pulseless electrical activity. Following admission, hyperthyroidism led to a suspicion of thyroid storm, which was then diagnosed as a possible cause of the cardiac arrest. Although hyperthyroidism-induced cardiac arrest including ventricular fibrillation is rare, it should be considered when diagnosing the cause of treatable cardiac arrest.Keywords: hyperthyroidism, ventricular fibrillation, treatable cardiac arrest, cardiac arrest, cardiopulmonary arrest

  6. ESR dating of tooth enamel samples

    International Nuclear Information System (INIS)

    Five tooth samples from the palaeoanthropological site of Jinniushan were dated with both electron-spin-resonance (ESR) and uranium-series techniques. The ESR age of about 230 ka is in good agreement with the U-series dating result, which confirms the hypothesis of possible coexistence of Homo erect us and Homo sapiens in China. Problems in ESR dating are discussed such as: 1) inappropriate of simple exponential extrapolation for accumulated dose determination; 2)experimental measurement of alpha detection efficiency and radon emanation and 3)selection of U-uptake model

  7. Measurement of Gear Tooth Dynamic Friction

    Science.gov (United States)

    Rebbechi, Brian; Oswald, Fred B.; Townsend, Dennis P.

    1996-01-01

    Measurements of dynamic friction forces at the gear tooth contact were undertaken using strain gages at the root fillets of two successive teeth. Results are presented from two gear sets over a range of speeds and loads. The results demonstrate that the friction coefficient does not appear to be significantly influenced by the sliding reversal at the pitch point, and that the friction coefficient values found are in accord with those in general use. The friction coefficient was found to increase at low sliding speeds. This agrees with the results of disc machine testing.

  8. Postoperative cardiac arrest due to cardiac surgery complications

    International Nuclear Information System (INIS)

    To examine the role of anesthetists in the management of cardiac arrest occurring in association with cardiac anesthesia. In this retrospective study we studied the potential performances for each of the relevant incidents among 712 patients undergoing cardiac operations at Golestan and Naft Hospitals Ahwaz between November 2006 and July 2008. Out of total 712 patients undergoing cardiac surgery, cardiac arrest occurred in 28 cases (3.9%) due to different postoperative complications. This included massive bleeding (50% of cardiac arrest cases, 1.9% of patients); pulseless supra ventricular tachycardia (28.5% of cardiac arrest cases, 1.1% of patients); Heart Failure (7% of cardiac arrest cases, 0.2% of patients); Aorta Arc Rapture (3.5% of cardiac arrest cases, 0.1% of patients); Tamponade due to pericardial effusion (3.5% of cardiac arrest cases, 0.1% of total patients); Right Atrium Rupture (3.5% of cardiac arrest cases, 0.1% of patients) were detected after cardiac surgery. Out of 28 cases 7 deaths occurred (25% of cardiac arrest cases, 0.1% of patients). The most prevalent reason for cardiac arrest during post operative phase was massive bleeding (50%) followed by pulseless supra ventricular tachycardia (28.5%). Six patients had some morbidity and the remaining 15 patients recovered. There are often multiple contributing factors to a cardiac arrest under cardiac anesthesia, as much a complete systematic assessment of the patient, equipment, and drugs should be completed. We also found that the diagnosis and management of cardiac arrest in association with cardiac anesthesia differs considerably from that encountered elsewhere. (author)

  9. Hospital Variation in Survival After In‐hospital Cardiac Arrest

    OpenAIRE

    Merchant, Raina M.; Berg, Robert A.; Yang, Lin; Becker, Lance B.; Groeneveld, Peter W.; Chan, Paul S.; ,

    2014-01-01

    Background In‐hospital cardiac arrest (IHCA) is common and often fatal. However, the extent to which hospitals vary in survival outcomes and the degree to which this variation is explained by patient and hospital factors is unknown. Methods and Results Within Get with the Guidelines‐Resuscitation, we identified 135 896 index IHCA events at 468 hospitals. Using hierarchical models, we adjusted for demographics comorbidities and arrest characteristics (eg, initial rhythm, etiology, arrest locat...

  10. Combined implant-residual tooth supported prosthesis after tooth hemisection: A finite element analysis.

    Science.gov (United States)

    He, Yun; Hasan, Istabrak; Keilig, Ludger; Chen, Junliang; Pan, Qing; Huang, Yue; Bourauel, Christoph

    2016-07-01

    Tooth hemisection preserves partial tooth structure and reduces the resorption of alveolar bone. The aim of this study was to analyze the feasibility of preserving a molar after hemisection and inserting a dental implant with different prosthetic superstructures by means of finite element analysis. First, the distance between the root of the mandibular second premolar and the distal root of the first molar were measured in 80 cone beam computed tomography (CBCT) data sets. Based on these data, the lower right posterior jaw segment was reconstructed and the geometries of the appropriate implant were imported. Four models were created: (1) Hemi-1: An implant (3.7×9mm) replaced the mesial root of the molar, and a single crown was placed on the implant and residual tooth. (2) Hemi-2: Two separate crowns were generated for the implant and the residual tooth. (3) Single: An implant (5.5×9mm) with crown replaced the whole molar. (4) FPD: A 3-unit fixed partial denture combined the distal residual part of the molar and premolar. The results indicated that stresses in the cortical bone and strains in the majority region of the spongious bone were below the physiological upper limits. There were higher stresses in implant with the Hemi-1 and Single models, which had the same maximum values of 45.0MPa. The FPD models represented the higher values of stresses in the teeth and strains in PDL compared to other models. From a biomechanical point of view, it can be concluded that a combination of an implant and residual molar after tooth hemisection is an acceptable treatment option. PMID:26851558

  11. Successful emergency splenectomy during cardiac arrest due to cytomegalovirus-induced atraumatic splenic rupture

    DEFF Research Database (Denmark)

    Glesner, Matilde Kanstrup; Madsen, Kristian Rørbæk; Nielsen, Jesper Meng Rahn;

    2015-01-01

    A 27-year-old woman was admitted to the emergency department with fever and a petechial rash on suspicion of meningitis. Shortly after arriving she developed cardiac arrest. Blood work up showed severe lactate acidosis, anaemia and thrombocytopenia. A focused assessment with sonography in trauma...... essential for the management and the eventual recovery of the patient....

  12. Airway Delivery of Mesenchymal Stem Cells Prevents Arrested Alveolar Growth in Neonatal Lung Injury in Rats

    OpenAIRE

    van Haaften, Timothy; Byrne, Roisin; Bonnet, Sebastien; Rochefort, Gael Y.; Akabutu, John; Bouchentouf, Manaf; Rey-Parra, Gloria J.; Galipeau, Jacques; Haromy, Alois; Eaton, Farah; Chen, Ming; Hashimoto, Kyoko; Abley, Doris; Korbutt, Greg; Archer, Stephen L.

    2009-01-01

    Rationale: Bronchopulmonary dysplasia (BPD) and emphysema are characterized by arrested alveolar development or loss of alveoli; both are significant global health problems and currently lack effective therapy. Bone marrow–derived mesenchymal stem cells (BMSCs) prevent adult lung injury, but their therapeutic potential in neonatal lung disease is unknown.

  13. Cardiac arrest during treatment of Pneumocystis carinii pneumonia with intravenous pentamidine isethionate

    DEFF Research Database (Denmark)

    Balslev, U; Berild, D; Nielsen, T L

    1992-01-01

    A 27-year-old man, HIV-positive for 4 years, developed ventricular fibrillation and cardiac arrest during treatment of Pneumocystis carinii pneumonia with intravenous pentamidine isethionate. The dosage was 4 mg/kg/day for 18 days. Nephrotoxicity occurred and raised serum potassium. The plasma...

  14. Respiratory arrest due to nitrofurantoin treatment in the absence of pulmonary pathology

    OpenAIRE

    Çoban, Hikmet

    2015-01-01

    In the case we present, an elderly female patient developed respiratory arrest in the absence of pulmonary pathology after using nitrofurantoin (NF). To our current knowledge, this case is the first in the literature. The patient was monitored on mechanical ventilation, and her condition improved only after discontinuing NF treatment.

  15. Dental histology of Coelophysis bauri and the evolution of tooth attachment tissues in early dinosaurs.

    Science.gov (United States)

    Fong, Raymond K M; LeBlanc, Aaron R H; Berman, David S; Reisz, Robert R

    2016-07-01

    Studies of dinosaur teeth have focused primarily on external crown morphology and thus, use shed or in situ tooth crowns, and are limited to the enamel and dentine dental tissues. As a result, the full suites of periodontal tissues that attach teeth to the jaws remain poorly documented, particularly in early dinosaurs. These tissues are an integral part of the tooth and thus essential to a more complete understanding of dental anatomy, development, and evolution in dinosaurs. To identify the tooth attachment tissues in early dinosaurs, histological thin sections were prepared from the maxilla and dentary of a partial skull of the early theropod Coelophysis bauri from the Upper Triassic (Rhaetian- 209-201 Ma) Whitaker Quarry, New Mexico, USA. As one of the phylogenetically and geologically oldest dinosaurs, it is an ideal candidate for examining dental tissues near the base of the dinosaurian clade. The teeth of C. bauri exhibited a fibrous tooth attachment in which the teeth possessed five tissues: enamel, dentine, cementum, periodontal ligament (PDL), and alveolar bone. Our findings, coupled with those of more recent studies of ornithischian teeth, indicate that a tripartite periodontium, similar to that of crocodilians and mammals, is the plesiomorphic condition for dinosaurs. The occurrence of a tripartite periodontium in dinosaurs adds to the growing consensus that the presence of these tissues is the plesiomorphic condition for the major amniote clades. Furthermore, this study establishes the relative timing of tissue development and growth directions of periodontal tissues and provides the first comparative framework for future studies of dinosaur periodontal development, tooth replacement, and histology. J. Morphol. 277:916-924, 2016. © 2016 Wiley Periodicals, Inc. PMID:27087142

  16. Hierarchical structure and biomineralization in cricket tooth

    CERN Document Server

    Xing, Xueqing; Cai, Quan; Mo, Guang; Du, Rong; Chen, Zhongjun; Wu, Zhonghua

    2012-01-01

    Cricket is a truculent insect with stiff and sharp teeth as a fighting weapon. The structure and possible biomineralization of the cricket teeth are always interested. Synchrotron radiation X-ray fluorescence, X-ray diffraction and small angle X-ray scattering techniques were used to probe the element distribution, possible crystalline structures and size distribution of scatterers in cricket teeth. Scanning electron microscope was used to observe the nanoscaled structure. The results demonstrate that Zn is the main heavy element in cricket teeth. The surface of the cricket teeth has a crystalline compound like ZnFe2(AsO4)2(OH)2(H2O)4. While, the interior of the teeth has a crystalline compound like ZnCl2, which is from the biomineralization. The ZnCl2-like biomineral forms nanoscaled microfibrils and their axial direction points at the top of tooth cusp. The microfibrils aggregate random into intermediate filaments, forming a hierarchical structure. A sketch map of the cricket tooth cusp was proposed and a d...

  17. Surviving Sudden Cardiac Arrest: A Pilot Qualitative Survey Study of Survivors.

    Science.gov (United States)

    Sawyer, Kelly N; Brown, Frances; Christensen, Roxanne; Damino, Colleen; Newman, Mary M; Kurz, Michael C

    2016-06-01

    Research describing survivors of sudden cardiac arrest (SCA) has centered on quantifying functional ability, perceived quality of life, and neurocognitive assessment. Many gaps remain, however, regarding survivors' psychosocial perceptions of life in the aftermath of cardiac arrest. An important influence upon those perceptions is the presence of support and its role in a survivor's life. An Internet-based pilot survey study was conducted to gather data from SCA survivors and friends and/or family members (FFMs) representing their support system. The survey was distributed to members of the Sudden Cardiac Arrest Foundation (SCAF) via the Internet by SCAF leadership. Questions included both discrete multiple-choice and open-ended formats. Inductive thematic analyses were completed by three independent researchers trained in qualitative research methodology to identify primary themes consistent among study participants until thematic saturation was achieved. No statistical inferences were made. A total of 205 surveys were returned over the 5-month study period (July to November 2013); nine were received blank, leaving 196 surveys available for review. Major themes identified for survivors (N = 157) include the significance of and desire to share experiences with others; subculture identification (unique experience from those suffering a heart attack); and the need to seek a new normal, both personally and inter-personally. Major themes identified for FFMs (N = 39) include recognition of loved one's memory loss; a lack of information at discharge, including expectations after discharge; and concern for the patient experiencing another cardiac arrest. This pilot, qualitative survey study suggests several common themes important to survivors, and FFMs, of cardiac arrest. These themes may serve as a basis for future patient-centered focus groups and the development of patient-centered guidelines for patients and support persons of those surviving cardiac arrest

  18. Crown-formation time of a fossil hominid premolar tooth.

    Science.gov (United States)

    Beynon, A D; Dean, M C

    1987-01-01

    Studies using surface or internal enamel growth indicators in hominids have suggested that crown-formation times were shorter than those in modern man. The crown-formation time in a robust australopithecine premolar tooth was calculated by counting enamel cross-striations, which correspond to daily increments of formation, on a replica of the fractured internal enamel surface of cuspal enamel using scanning electron microscopy. Cervical enamel completion time was estimated using other growth indicators including striae, and using measured and calculated cross-striation repeat intervals, giving a completion time of approx. 2.4 yr. This is much shorter than reported premolar crown formation times in modern man. These findings support the concept of an abbreviated period of dental development, with implications on the duration of the growth period in early hominids. PMID:3130039

  19. Tooth-colored CAD/CAM monolithic restorations.

    Science.gov (United States)

    Reich, S

    2015-01-01

    A monolithic restoration (also known as a full contour restoration) is one that is manufactured from a single material for the fully anatomic replacement of lost tooth structure. Additional staining (followed by glaze firing if ceramic materials are used) may be performed to enhance the appearance of the restoration. For decades, monolithic restoration has been the standard for inlay and partial crown restorations manufactured by both pressing and computer-aided design and manufacturing (CAD/CAM) techniques. A limited selection of monolithic materials is now available for dental crown and bridge restorations. The IDS (2015) provided an opportunity to learn about and evaluate current trends in this field. In addition to new developments, established materials are also mentioned in this article to complete the picture. In line with the strategic focus of the IJCD, the focus here is naturally on CAD/CAM materials. PMID:26110926

  20. [Tooth regeneration in the guinea pig (Cavia porcellus)].

    Science.gov (United States)

    Stephan, F; Artis, J P; Lanot, R

    1977-01-01

    The first inferior molar has been extracted, a part of its being reimplanted or not. A new molar of normal form regenerated, apparently from the apex of the tooth germ, in all cases in which the alveolus was left free or implanted with a tooth freagment deprived of pulpa. PMID:145296

  1. 3D Simulation Modeling of the Tooth Wear Process.

    Directory of Open Access Journals (Sweden)

    Ning Dai

    Full Text Available Severe tooth wear is the most common non-caries dental disease, and it can seriously affect oral health. Studying the tooth wear process is time-consuming and difficult, and technological tools are frequently lacking. This paper presents a novel method of digital simulation modeling that represents a new way to study tooth wear. First, a feature extraction algorithm is used to obtain anatomical feature points of the tooth without attrition. Second, after the alignment of non-attrition areas, the initial homogeneous surface is generated by means of the RBF (Radial Basic Function implicit surface and then deformed to the final homogeneous by the contraction and bounding algorithm. Finally, the method of bilinear interpolation based on Laplacian coordinates between tooth with attrition and without attrition is used to inversely reconstruct the sequence of changes of the 3D tooth morphology during gradual tooth wear process. This method can also be used to generate a process simulation of nonlinear tooth wear by means of fitting an attrition curve to the statistical data of attrition index in a certain region. The effectiveness and efficiency of the attrition simulation algorithm are verified through experimental simulation.

  2. Nondestructive Assessment of Early Tooth Demineralization Using Cross-Polarization Optical Coherence Tomography.

    Science.gov (United States)

    Kang, Hobin; Jiao, Jian J; Lee, Chulsung; Le, Michael H; Darling, Cynthia L; Fried, Daniel

    2010-07-01

    New methods are needed for the nondestructive measurement of tooth demineralization and remineralization to monitor the progression of incipient caries lesions (tooth decay) for effective nonsurgical intervention and to evaluate the performance of anticaries treatments such as chemical treatments or laser irradiation. Studies have shown that optical coherence tomography (OCT) has great potential to fulfill this role since it can be used to measure the depth and severity of early lesions with an axial resolution exceeding 10 µm, it is easy to apply in vivo and it can be used to image the convoluted topography of tooth occlusal surfaces. In this paper, a review of the use of polarization-sensitive-OCT for the measurement of tooth demineralization is provided along with some recent results regarding improved methods for the detection of caries lesions in the earliest stages of development. Automated methods of analysis were used to measure the depth and severity of demineralized bovine enamel produced using simulated caries models that emulate demineralization in the mouth. Significant differences in the depth and integrated reflectivity from the lesions were detected after only a few hours of demineralization. These results demonstrate that cross-polarization-OCT is ideally suited for the nondestructive assessment of early demineralization. PMID:21660217

  3. In-air micro-PIGE measurement system for fluorine analysis of the tooth

    Energy Technology Data Exchange (ETDEWEB)

    Yasuda, K. [Wakasa Wan Energy Research Center, 64-52-1 Nagatani, Tsuruga, Fukui 914-0192 (Japan)]. E-mail: kyasuda@werc.or.jp; Hai, V.H. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Nomachi, M. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Sugaya, Y. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Yamamoto, H. [Graduate School of Dentistry, Osaka University, 1-8 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2007-07-15

    An in-air micro-PIGE and micro-PIXE measurement system for fluorine analysis of tooth have been developed at the Wakasa Wan Energy Research Center. A proton microbeam is extracted through a thin silicon nitride window into the air and used to irradiate a tooth sample mounted on a sample stage set in air. Gamma-rays from a {sup 19}F(p,{alpha}{gamma}){sup 16}O reaction and characteristic X-rays are detected with a BGO detector and a Ge X-ray detector, simultaneously. The sample stage and beam scanner allow us to analyze the tooth sample over a range of 20 mm at maximum. Spot sizes of a proton beams in air at an energy of 2.5 MeV was 4 {mu}m, in the case of a distance between the silicon nitride window and the sample of 0.2 mm and 13 {mu}m in the case of 1.7 mm. Fluorine analysis was performed over an area of about 3 mm x 3 mm of the tooth sample. One- and two-dimensional distributions of fluorine and calcium were obtained successfully. Quantitative analysis was also performed using data for measurements of reference materials Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2-2x}F{sub 2x}.

  4. Surgical Methods for the Acceleration of the Orthodontic Tooth Movement.

    Science.gov (United States)

    Almpani, Konstantinia; Kantarci, Alpdogan

    2016-01-01

    Surgical techniques for the acceleration of the orthodontic tooth movement have been tested for more than 100 years in clinical practice. Since original methods have been extremely invasive and have been associated with increased tooth morbidity and various other gaps, the research in this field has always followed an episodic trend. Modern approaches represent a well-refined strategy where the concept of the bony block has been abandoned and only a cortical plate around the orthodontic tooth movement has been desired. Selective alveolar decortication has been a reproducible gold standard to this end. Its proposed mechanism has been the induction of rapid orthodontic tooth movement through the involvement of the periodontal ligament. More recent techniques included further refinement of this procedure through less invasive techniques such as the use of piezoelectricity and corticision. This chapter focuses on the evolution of the surgical approaches and the mechanistic concepts underlying the biological process during the surgically accelerated orthodontic tooth movement. PMID:26599122

  5. Dynamical Arrest, Structural Disorder, and Optimization of Organic Photovoltaic Devices

    Energy Technology Data Exchange (ETDEWEB)

    Gould, Ian; Dmitry, Matyushov

    2014-09-11

    This project describes fundamental experimental and theoretical work that relates to charge separation and migration in the solid, heterogeneous or aggregated state. Marcus theory assumes a system in equilibrium with all possible solvent (dipolar) configurations, with rapid interconversion among these on the ET timescale. This project has addressed the more general situation where the medium is at least partially frozen on the ET timescale, i.e. under conditions of dynamical arrest. The approach combined theory and experiment and includes: (1) Computer simulations of model systems, (2) Development of analytical procedures consistent with computer experiment and (3) Experimental studies and testing of the formal theories on this data. Electron transfer processes are unique as a consequence of the close connection between kinetics, spectroscopy and theory, which is an essential component of this work.

  6. Anaphylactic shock and cardiac arrest caused by thiamine infusion.

    Science.gov (United States)

    Juel, Jacob; Pareek, Manan; Langfrits, Christian Sigvald; Jensen, Svend Eggert

    2013-01-01

    Parenteral thiamine has a very high safety profile. The most common adverse effect is local irritation; however, anaphylactic or anaphylactoid reactions may occur, mostly related to intravenous administration. We describe a 44-year-old man, a chronic alcoholic, who was admitted with alcohol intoxication and developed cardiac arrest due to anaphylactic shock following intravenous thiamine infusion. The patient was successfully resuscitated after 15 min and repeated epinephrine administrations. He was discharged in good health after 14 days. This case report emphasises both the importance of recognising the symptoms of anaphylaxis and the fact that facilities for treating anaphylaxis and cardiopulmonary resuscitation should be available when thiamine or for that matter, any drug is given in-hospital. PMID:23853017

  7. Involvement of Mos-MEK-MAPK pathway in cytostatic factor (CSF) arrest in eggs of the parthenogenetic insect, Athalia rosae.

    Science.gov (United States)

    Yamamoto, Daisuke S; Tachibana, Kazunori; Sumitani, Megumi; Lee, Jae Min; Hatakeyama, Masatsugu

    2008-01-01

    Extensive survey of meiotic metaphase II arrest during oocyte maturation in vertebrates revealed that the mitogen-activated protein kinase (MAPK) pathway regulated by the c-mos proto-oncogene product, Mos, has an essential role in cytostatic activity, termed cytostatic factor (CSF). In contrast, little is known in invertebrates in which meiotic arrest occurs in most cases at metaphase I (MI arrest). A parthenogenetic insect, the sawfly Athalia rosae, in which artificial egg activation is practicable, has advantages to investigate the mechanisms of MI arrest. Both the MAPK/extracellular signal-regulated protein kinase kinase (MEK) and MAPK were phosphorylated and maintained active in MI-arrested sawfly eggs, whereas they were dephosphorylated soon after egg activation. Treatment of MI-arrested eggs with U0126, an inhibitor of MEK, resulted in dephosphorylation of MAPK and MI arrest was resumed. The sawfly c-mos gene orthologue encoding a serine/threonine kinase was cloned and analyzed. It was expressed in nurse cells in the ovaries. To examine CSF activity of the sawfly Mos, synthesized glutathione S-transferase (GST)-fusion sawfly Mos protein was injected into MI-resumed eggs in which MEK and MAPK were dephosphorylated. Both MEK and MAPK were phosphorylated again upon injection. In these GST-fusion sawfly Mos-injected eggs subsequent mitotic (syncytial) divisions were blocked and embryonic development was ceased. These results demonstrated that the MEK-MAPK pathway was involved in maintaining CSF arrest in sawfly eggs and Mos functioned as its upstream regulatory molecule. PMID:18793721

  8. Resuscitation, prolonged cardiac arrest, and an automated chest compression device

    DEFF Research Database (Denmark)

    Risom, Martin; Jørgensen, Henrik; Rasmussen, Lars S;

    2010-01-01

    The European Resuscitation Council's 2005 guidelines for cardiopulmonary resuscitation (CPR) emphasize the delivery of uninterrupted chest compressions of adequate depth during cardiac arrest.......The European Resuscitation Council's 2005 guidelines for cardiopulmonary resuscitation (CPR) emphasize the delivery of uninterrupted chest compressions of adequate depth during cardiac arrest....

  9. Growth arrest specific protein (GAS) 6

    DEFF Research Database (Denmark)

    Haase, T N; Rasmussen, Morten; Jaksch, C A M; Gaarn, L W; Petersen, Camilla K; Billestrup, N; Nielsen, Jens Høiriis

    2013-01-01

    Aims/hypothesis Maternal low-protein (LP) diet during gestation results in a reduced beta cell mass in the offspring at birth and this may hamper the ability to adapt to high-energy food and sedentary lifestyle later in life. To investigate the biology behind the LP-offspring phenotype, this study...... using RNA microarray and quantitative PCR. The role of a differentially expressed gene, growth arrest specific protein 6 (GAS6), was evaluated in vitro using neonatal rat islets. Results The mRNA level of Gas6, known to be mitogenic in other tissues, was reduced in LP offspring. The mRNA content of Mafa...... was increased in LP offspring suggesting an early maturation of beta cells. When applied in vitro, GAS6 increased proliferation of neonatal pancreatic beta cells, while reducing glucose-stimulated insulin secretion without changing the total insulin content of the islets. In addition, GAS6 decreased...

  10. Interdisciplinary Approach to a Tooth with Open Apex and Persistent Sinus

    OpenAIRE

    Das, Anoop N.; Krishnamohan Geetha; Ajay Varghese Kurian; Radhakrishnan Nair; Nandakumar, K

    2015-01-01

    Traumatic injuries in childhood may disrupt root development leading to a tooth with open apex. Apexification procedures in such cases aim at root end closure after reasonable period of time. In some chronic cases, complete healing of the periapical area does not occur resulting in development of a nonhealing sinus. Failure of nonsurgical approach in such cases needs surgical intervention permitting thorough periapical curettage. In the present case, apexification procedure with MTA achieved ...

  11. Magnesium stable isotope ecology using mammal tooth enamel

    Science.gov (United States)

    Martin, Jeremy E.; Vance, Derek; Balter, Vincent

    2015-01-01

    Geochemical inferences on ancient diet using bone and enamel apatite rely mainly on carbon isotope ratios (δ13C) and to a lesser extent on strontium/calcium (Sr/Ca) and barium/calcium (Ba/Ca) elemental ratios. Recent developments in nontraditional stable isotopes provide an unprecedented opportunity to use additional paleodietary proxies to disentangle complex diets such as omnivory. Of particular relevance for paleodietary reconstruction are metals present in large quantity in bone and enamel apatite, providing that biologically mediated fractionation processes are constrained. Calcium isotope ratios (δ44Ca) meet these criteria but exhibit complex ecological patterning. Stable magnesium isotope ratios (δ26Mg) also meet these criteria but a comprehensive understanding of its variability awaits new isotopic data. Here, 11 extant mammal species of known ecology from a single locality in equatorial Africa were sampled for tooth enamel and, together with vegetation and feces, analyzed for δ26Mg, δ13C, Sr/Ca, and Ba/Ca ratios. The results demonstrate that δ26Mg incorporated in tooth enamel becomes heavier from strict herbivores to omnivores/faunivores. Using data from experimentally raised sheep, we suggest that this 26Mg enrichment up the trophic chain is due to a 26Mg enrichment in muscle relative to bone. Notably, it is possible to distinguish omnivores from herbivores, using δ26Mg coupled to Ba/Ca ratios. The potential effects of metabolic and dietary changes on the enamel δ26Mg composition remain to be explored but, in the future, multiproxy approaches would permit a substantial refinement of dietary behaviors or enable accurate trophic reconstruction despite specimen-limited sampling, as is often the case for fossil assemblages.

  12. Magnesium stable isotope ecology using mammal tooth enamel.

    Science.gov (United States)

    Martin, Jeremy E; Vance, Derek; Balter, Vincent

    2015-01-13

    Geochemical inferences on ancient diet using bone and enamel apatite rely mainly on carbon isotope ratios (δ(13)C) and to a lesser extent on strontium/calcium (Sr/Ca) and barium/calcium (Ba/Ca) elemental ratios. Recent developments in nontraditional stable isotopes provide an unprecedented opportunity to use additional paleodietary proxies to disentangle complex diets such as omnivory. Of particular relevance for paleodietary reconstruction are metals present in large quantity in bone and enamel apatite, providing that biologically mediated fractionation processes are constrained. Calcium isotope ratios (δ(44)Ca) meet these criteria but exhibit complex ecological patterning. Stable magnesium isotope ratios (δ(26)Mg) also meet these criteria but a comprehensive understanding of its variability awaits new isotopic data. Here, 11 extant mammal species of known ecology from a single locality in equatorial Africa were sampled for tooth enamel and, together with vegetation and feces, analyzed for δ(26)Mg, δ(13)C, Sr/Ca, and Ba/Ca ratios. The results demonstrate that δ(26)Mg incorporated in tooth enamel becomes heavier from strict herbivores to omnivores/faunivores. Using data from experimentally raised sheep, we suggest that this (26)Mg enrichment up the trophic chain is due to a (26)Mg enrichment in muscle relative to bone. Notably, it is possible to distinguish omnivores from herbivores, using δ(26)Mg coupled to Ba/Ca ratios. The potential effects of metabolic and dietary changes on the enamel δ(26)Mg composition remain to be explored but, in the future, multiproxy approaches would permit a substantial refinement of dietary behaviors or enable accurate trophic reconstruction despite specimen-limited sampling, as is often the case for fossil assemblages. PMID:25535375

  13. Maturation arrest of human oocytes at germinal vesicle stage

    Directory of Open Access Journals (Sweden)

    Zhi Qin Chen

    2010-01-01

    Full Text Available Maturation arrest of human oocytes may occur at various stages of the cell cycle. A total failure of human oocytes to complete meiosis is rarely observed during assisted conception cycles. We describe here a case of infertile couples for whom all oocytes repeatedly failed to mature at germinal vesicle (GV stage during in vitro fertilization/Intra cytoplasmic sperm injection (IVF/ICSI. The patient underwent controlled ovarian stimulation followed by oocyte retrieval and IVF/ICSI. The oocytes were stripped off cumulus cells prior to the ICSI procedure and their maturity status was defined. The oocyte maturation was repeatedly arrested at the GV. Oocyte maturation arrest may be the cause of infertility in this couple. The recognition of oocyte maturation arrest as a specific medical condition may contribute to the characterization of the currently known as "oocyte factor." The cellular and genetic mechanisms causing oocyte maturation arrest should be the subject for further investigation.

  14. Laser therapy for faster orthodontic tooth movement

    Directory of Open Access Journals (Sweden)

    Wasundhara A Bhad-Patil

    2014-01-01

    Full Text Available One of the major component of patient to reject orthodontic treatment is the long duration of treatment..If Low intensity laser therapy can promote wound healing by increased cell proliferation and improved micro circulation can bring about faster bone remodelling at fracture sites; then why not to use it with orthodontic forces for better results? Soft tissue laser has now become a part of essential equipment of modern dental clinics. To accelerate the physiologic tooth movement during orthodontic treatment a thorough knowledge of laser unit, mode of action and key factors to gain therapeutic effect is a must which this article illustrates .Study carried out by us did show a 30% reduction in the treatment time.

  15. Unusual intraosseous transmigration of impacted tooth

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Santosh; Urala, Arun Srinivas; Kamath, Abhay Taranath; Jayaswal, Priyanka; Valiathan, Ashima [Manipal College of Dental Sciences, Manipal (India)

    2012-03-15

    Transmigration of an impacted tooth through the symphyseal suture is a rare and special developmental anomaly of unknown etiology that is unique to the mandibular canine. Maxillary canine transmigration is even rarer. Transmigrated canines are particularly significant due to the aesthetic and functional importance. A maxillary lateral incisor crossing the mid-palatal suture has never been reported in the literature. The aim of this report is to present the first case of simultaneous transmigration of a lateral incisor and canine in the maxilla. The paper also reports four unusual cases of unilateral canine transmigration in the maxilla and mandible and successful eruption of one of the transmigrated mandibular canines following orthodontic traction. Etiology of transmigration and its clinical considerations are also discussed.

  16. Side effects of external tooth bleaching

    DEFF Research Database (Denmark)

    E.M., Bruzell; Pallesen, Ulla; Thoresen, N.R.;

    2013-01-01

    -office = 39.3% [n = 28]; p >0.05; 95% CI [OR]: 0.198‑1.102) whereas prevalence of gingival irritation was higher after in-office treatment (at-home = 14.0%; in-office = 35.7%; p <0.05) (mean age: 37.3 years; 73.7% women; n = 171). At the second follow-up, two and three patients reported side effects...... attributed to the bleaching treatment in the at-home and in-office groups, respectively. Predictors for side effects were tooth sensitivity, surface loss and gingivitis when observed at inclusion. Treatment-related predictors were bleaching concentration and contact between tray and gingiva. Conclusions...

  17. Intense ultrasonic clicks from echolocating toothed whales do not elicit anti-predator responses or debilitate the squid Loligo pealeii

    DEFF Research Database (Denmark)

    Wilson, Maria; Hanlon, R.T.; Tyack, P.L.;

    2007-01-01

    Toothed whales use intense ultrasonic clicks to echolocate prey and it has been hypothesized that they also acoustically debilitate their prey with these intense sound pulses to facilitate capture. Cephalopods are an important food source for toothed whales, and there has probably been an...... evolutionary selection pressure on cephalopods to develop a mechanism for detecting and evading sound-emitting toothed whale predators. Ultrasonic detection has evolved in some insects to avoid echolocating bats, and it can be hypothesized that cephalopods might have evolved similar ultrasound detection as an......) do not acoustically debilitate this cephalopod species....

  18. Involvement of and interaction between WNT10A and EDA mutations in tooth agenesis cases in the Chinese population.

    Directory of Open Access Journals (Sweden)

    Huiying He

    Full Text Available BACKGROUND: Dental agenesis is the most common, often heritable, developmental anomaly in humans. Although WNT10A gene mutations are known to cause rare syndromes associated with tooth agenesis, including onycho-odontodermal dysplasia (OODD, Schöpf-Schulz-Passarge syndrome (SSPS, hypohidrotic ectodermal dysplasia (HED, and more than half of the cases of isolated oligodontia recently, the genotype-phenotype correlations and the mode of inheritance of WNT10A mutations remain unclear. The phenotypic expression with WNT10A mutations shows a high degree of variability, suggesting that other genes might function with WNT10A in regulating ectodermal organ development. Moreover, the involvement of mutations in other genes, such as EDA, which is also associated with HED and isolated tooth agenesis, is not clear. Therefore, we hypothesized that EDA mutations interact with WNT10A mutations to play a role in tooth agenesis. Additionally, EDA, EDAR, and EDARADD encode signaling molecules in the Eda/Edar/NF-κB signaling pathways, we also checked EDAR and EDARADD in this study. METHODS: WNT10A, EDA, EDAR and EDARADD were sequenced in 88 patients with isolated oligodontia and 26 patients with syndromic tooth agenesis. The structure of two mutated WNT10A and two mutated EDA proteins was analyzed. RESULTS: Digenic mutations of both WNT10A and EDA were identified in 2 of 88 (2.27% isolated oligodontia cases and 4 of 26 (15.38% syndromic tooth agenesis cases. No mutation in EDAR or EDARADD gene was found. CONCLUSIONS: WNT10A and EDA digenic mutations could result in oligodontia and syndromic tooth agenesis in the Chinese population. Moreover, our results will greatly expand the genotypic spectrum of tooth agenesis.

  19. Tooth loss and obstructive sleep apnoea

    Directory of Open Access Journals (Sweden)

    Gai Valerio

    2006-01-01

    Full Text Available Abstract Background Complete tooth loss (edentulism produces anatomical changes that may impair upper airway size and function. The aim of this study was to evaluate whether edentulism favours the occurrence of obstructive sleep apnoea (OSA. Methods Polysomnography was performed in 48 edentulous subjects on two consecutive nights, one slept with and the other without dentures. Upper airway size was assessed by cephalometry and by recording forced mid-inspiratory airflow rate (FIF50. Exhaled nitric oxide (eNO and oral NO (oNO, were measured as markers of airway and oropharyngeal inflammation. Results The apnoea/hypopnoea index (AHI without dentures was significantly higher than with dentures (17·4 ± 3·6 versus 11·0 ± 2·3. p = 0·002, and was inversely related to FIF50 (p = 0·017 and directly related to eNO (p = 0·042. Sleeping with dentures, 23 subjects (48% had an AHI over 5, consistent with OSA, but sleeping without dentures the number of subjects with abnormal AHI rose to 34 (71%. At cephalometry, removing dentures produced a significant decrease in retropharyngeal space (from 1·522 ± 0·33 cm to 1·27 ± 0·42 cm, p = 0·006. Both morning eNO and oNO were higher after the night slept without dentures (eNO 46·1 ± 8·2 ppb versus 33·7 ± 6·3 ppb, p = 0·035, oNO 84·6 ± 13·7 ppb versus 59·2 ± 17·4 ppb, p = 0·001. Conclusion These findings suggest that complete tooth loss favours upper airway obstruction during sleep. This untoward effect seems to be due to decrease in retropharyngeal space and is associated with increased oral and exhaled NO concentration.

  20. TOOTH BRUSH - TOOTH PASTE OCULAR INJURY: A SEQUELAE TO FAST LIFE

    Directory of Open Access Journals (Sweden)

    Anil Kumar

    2015-01-01

    Full Text Available Toothbrush - tooth paste, widely used in every house hold, may cause irreversible injury to the eye especially cornea that comes into contact with this substance. We present two cases of toothbrush - toothpaste injury who accidentally injured their own eye. T hese were combination of chemical ( T oothpaste and trivial mechanical ( T oothbrush trauma. Ocular contact with toothpaste causes severe unbearable burning sensation. One of the cases developed suppurative corneal ulcer with hypopyon and lost vision in the affected eye. Toothpastes with more ph can cause blindness when it comes into contact with the eye if not treated urgently. The other patient ( O ne of the consultants in our institute reported immediately in the morning in emergency with complaints of seve re burning sensation in the involved eye after accidental injury with toothbrush - toothpaste. His eyes were washed with normal saline for 30 to 40 minutes. Because he was treated immediately, he recovered within one week. Clinicians should take adequate pre cautions to prevent serious complication. In case of an accidental contact of eye with toothpaste, it is important to wash the eye efficiently. We decided to estimate the ph of commonly used various brands of toothpaste in over biochemistry lab and it was found that ph of various toothpaste varies from 7 to 10. The pH of the brand of the toothpaste which was used by one of the case was (pH 9.6, which shows that it is a combination of mechanical and alkali injury. pH near to neutral (7.1 and 7.4 was detect ed in one of the herbal toothpaste and one the oldest brand of toothpaste ( W hich was not herbal. These cases are being reported to make aware the ophthalmologists and public that although rare but these cases should not be taken lightly and should be trea ted urgently to prevent the loss of vision in the involved eye. One of the risk factors, may be the hurried activities in the morning in this era of fast life a s one of the

  1. Mesiodistal tooth angulation to segmental occlusal plane in panoramic radiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Duk; Kim, Jin Soo; You, Choong Hyun [Chosun University College of Medicine, Kwangju (Korea, Republic of)

    2005-03-15

    To evaluate the stability of the segmental occlusal plane and anatomical line as the reference line for measuring the mesiodistal tooth angulation in panoramic radiography and to determine the mean angle and the range of the mesiodistal tooth angulation in Korean population with normal occlusions. Twenty nine subjects (15 men, 14 women) with normal occlusion were selected. A total of 29 panoramic radiograms were taken at normal head position and then 10 images of 5 subjects selected were repeatedly taken with repositioning 2 times at each of the head down (V-shaped occlusion) and up (horizontal occulsion) for evaluation of stability of adopted reference lines by using PM2002CC (Planmeca, Finland). The images were traced with adoption of two test reference lines and the long axes of the teeth. The mesial angles formed by each reference line and the long axes of the teeth were measured and analyzed. With anatomical reference line, the mesiodistal tooth angulations of the molars showed the significant difference by over 5 degree between the normal and each changed head position. With segmented occlusal reference line, deviations of mesiodistal tooth angulations by the two changed head positions were less than 1 degree. The means, standard deviations, and maximum and minimum values of mesiodistal tooth angulations to segmental occlusal reference line on panoramic radiography were determined. It would appear that mesiodistal tooth angulations to segmental occlusal plane as reference line in panograms are predictable as standards of normal occlusion and useful for evaluation of tooth arrangement between adjacent teeth.

  2. Mesiodistal tooth angulation to segmental occlusal plane in panoramic radiography

    International Nuclear Information System (INIS)

    To evaluate the stability of the segmental occlusal plane and anatomical line as the reference line for measuring the mesiodistal tooth angulation in panoramic radiography and to determine the mean angle and the range of the mesiodistal tooth angulation in Korean population with normal occlusions. Twenty nine subjects (15 men, 14 women) with normal occlusion were selected. A total of 29 panoramic radiograms were taken at normal head position and then 10 images of 5 subjects selected were repeatedly taken with repositioning 2 times at each of the head down (V-shaped occlusion) and up (horizontal occulsion) for evaluation of stability of adopted reference lines by using PM2002CC (Planmeca, Finland). The images were traced with adoption of two test reference lines and the long axes of the teeth. The mesial angles formed by each reference line and the long axes of the teeth were measured and analyzed. With anatomical reference line, the mesiodistal tooth angulations of the molars showed the significant difference by over 5 degree between the normal and each changed head position. With segmented occlusal reference line, deviations of mesiodistal tooth angulations by the two changed head positions were less than 1 degree. The means, standard deviations, and maximum and minimum values of mesiodistal tooth angulations to segmental occlusal reference line on panoramic radiography were determined. It would appear that mesiodistal tooth angulations to segmental occlusal plane as reference line in panograms are predictable as standards of normal occlusion and useful for evaluation of tooth arrangement between adjacent teeth.

  3. Digital modeling technology for full dental crown tooth preparation.

    Science.gov (United States)

    Dai, Ning; Zhong, Yicheng; Liu, Hao; Yuan, Fusong; Sun, Yuchun

    2016-04-01

    A dental defect is one of the most common oral diseases, and it often requires a full crown restoration. In this clinical operation, the dentist must manually prepare the affected tooth for the full crown so that it has a convergence angle between 4° and 10°, no undercuts, and uniform and even shoulder widths and depths using a high speed diamond bur in the patient׳s mouth within one hour, which is a difficult task that requires visual-manual operation. The quality of the tooth preparation has an important effect on the success rate of the subsequent prosthodontic treatment. This study involved research into digital modeling technology for full dental crown tooth preparation. First, the margin line of the tooth preparation was designed using a semi-automatic interactive process. Second, the inserting direction was automatically computed. Then, the characteristic parameters and the constraints on the tooth preparation were defined for the model. Next, the shoulder and axial surface of the tooth preparation were formed using parametric modeling. Finally, the implicit surface of a radial basis function was used to construct the tooth preparation׳s occlusal surface. The experimental results verified that the method of digital modeling for full crown preparation proposed in this study can quickly and accurately implement personalized designs of various parameters, such as the shoulder width and the convergence angle; it provides a digital design tool for full crown preparation. PMID:26945598

  4. Dux4 induces cell cycle arrest at G1 phase through upregulation of p21 expression

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Hongliang; Wang, Zhaoxia; Jin, Suqin; Hao, Hongjun [Department of Neurology, Peking University First Hospital, Beijing 100034 (China); Zheng, Lemin [The Institute of Cardiovascular Sciences, Peking University Health Science Center, Key Laboratory of Molecular Cardiovascular Sciences of Education Ministry, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides of Health Ministry, Beijing 100191 (China); Zhou, Boda [The Department of Cardiology, Peking University Third Hospital, Beijing 100191 (China); Zhang, Wei; Lv, He [Department of Neurology, Peking University First Hospital, Beijing 100034 (China); Yuan, Yun, E-mail: yuanyun2002@sohu.com [Department of Neurology, Peking University First Hospital, Beijing 100034 (China)

    2014-03-28

    Highlights: • Dux4 induced TE671 cell proliferation defect and G1 phase arrest. • Dux4 upregulated p21 expression without activating p53. • Silencing p21 rescued Dux4 mediated proliferation defect and cell cycle arrest. • Sp1 binding site was required for Dux4-induced p21 promoter activation. - Abstract: It has been implicated that Dux4 plays crucial roles in development of facioscapulohumeral dystrophy. But the underlying myopathic mechanisms and related down-stream events of this retrogene were far from clear. Here, we reported that overexpression of Dux4 in a cell model TE671 reduced cell proliferation rate, and increased G1 phase accumulation. We also determined the impact of Dux4 on p53/p21 signal pathway, which controls the checkpoint in cell cycle progression. Overexpression of Dux4 increased p21 mRNA and protein level, while expression of p53, phospho-p53 remained unchanged. Silencing p21 rescued Dux4 mediated proliferation defect and cell cycle arrest. Furthermore, we demonstrated that enhanced Dux4 expression increased p21 promoter activity and elevated expression of Sp1 transcription factor. Mutation of Sp1 binding site decreased dux4 induced p21 promoter activation. Chromatin immunoprecipitation (ChIP) assays confirmed the Dux4-induced binding of Sp1 to p21 promoter in vivo. These results suggest that Dux4 might induce proliferation inhibition and G1 phase arrest through upregulation of p21.

  5. F-MARC: promoting the prevention and management of sudden cardiac arrest in football.

    Science.gov (United States)

    Kramer, Efraim Benjamin; Dvorak, J; Schmied, C; Meyer, T

    2015-05-01

    Sudden cardiac death is the most common cause of unnatural death in football. To prevent and urgently manage sudden cardiac arrest on the football field-of-play, F-MARC (FIFA Medical and Research Centre) has been fully committed to a programme of research, education, standardisation and practical implementation. This strategy has detected football players at medical risk during mandatory precompetition medical assessments. Additionally, FIFA has (1) sponsored internationally accepted guidelines for the interpretation of an athlete's ECG, (2) developed field-of-play-specific protocols for the recognition, response, resuscitation and removal of a football player having sudden cardiac arrest and (3) introduced and distributed the FIFA medical emergency bag which has already resulted in the successful resuscitation of a football player who had a sudden cardiac arrest on the field-of-play. Recently FIFA, in association with the Institute of Sports and Preventive Medicine in Saarbrücken, Germany, established a worldwide Sudden Death Registry with a view to documenting fatal events on the football field-of-play. These activities by F-MARC are testimony to FIFA's continued commitment to minimising sudden cardiac arrest while playing football. PMID:25878076

  6. Tooth loss prevalence among cardiac males and females

    International Nuclear Information System (INIS)

    Objective of study was to observe differences of tooth loss prevalence in males and females with Cardiac diseases Poor oral health, tooth loss and periodontal diseases have been reported to be associated with coronary heart diseases. Studies report gender differences in prevalence of cardiac diseases and tooth loss. This paper presents gender differences of tooth loss in cardiac patients of a cardiac hospital of Lahore, Pakistan. Methodology: Age matched Cardiac males and females attending OPD of the Punjab Institute of Cardiology (PIC), Lahore were included in the study. Personal and health-related information were questioned and noted. Oral examination was performed for recording of missing teeth. 1200 CHD study subjects with age-range of 30 to 80 years were enrolled for study. 1045 age matched, 766 (73.30%) males and 279 (26.70%) females were examined for tooth loss. 852 (81.53%) genders had at least one tooth missing. 599 (78.19) males and 253 (90.68%) females were observed with mean tooth loss of 7.5 (SD 8.720) and 11.15 (SD 10.375)respectively statistical association among them was also significant (P= 0.000) with OR of 2.339. More subjects (76.29%) showed a loss of 1-15 teeth that I was also significant among males and females. Tooth loss was significant in age groups of 41-50 years (P=0.001) and 51-60 years (P=0.000) Gender differences of tooth loss prevalence among CHD Subjects were significant with more risk for males as compared to females. (author)

  7. Developmentally arrested Austrofundulus limnaeus embryos have changes in post-translational modifications of histone H3.

    Science.gov (United States)

    Toni, Lee S; Padilla, Pamela A

    2016-02-01

    Although vertebrate embryogenesis is typically a continuous and dynamic process, some embryos have evolved mechanisms to developmentally arrest. The embryos of Austrofundulus limnaeus, a killifish that resides in ephemeral ponds, routinely enter diapause II (DII), a reversible developmental arrest promoted by endogenous cues rather than environmental stress. DII, which starts at 24-26 days post-fertilization and can persist for months, is characterized by a significant decline in heart rate and an arrest of development and differentiation. Thus, A. limnaeus is a unique model to study epigenetic features associated with embryonic arrest. To investigate chromosome structures associated with mitosis or gene expression, we examined the post-translational modifications of histone H3 (phosphorylation of serine 10, mono-, di- and tri-methylation of lysine 4 or 27) in preDII, DII and postDII embryos. As seen by microscopy analysis, DII embryos have a significant decrease in the H3S10P marker for mitotic nuclei and an inner nuclear membrane localization of the H3K27me2 marker associated with silencing of gene expression. ELISA experiments reveal that the levels of methylation at H3K4 and H3K27 are significantly different between preDII, DII and postDII embryos, indicating that there are molecular differences between embryos of different chronological age and stage of development. Furthermore, in DII embryos relative to preDII embryos, there are differences in the level of H3K27me3 and H3K4me3, which may reflect critical chromatin remodeling that occurs prior to arrest of embryogenesis. This work helps lay a foundation for chromatin analysis of vertebrate embryo diapause, an intriguing yet greatly understudied phenomenon. PMID:26685169

  8. Effect of Cervical Lessions on the Tooth FEM Study

    Directory of Open Access Journals (Sweden)

    Gabriela Bereşescu

    2010-12-01

    Full Text Available The approach used until recently concerning the phenomena of dental abfraction points to the conclusion that the cervical area of the tooth, were this type of lesion usually occur, concentrates the stress resulted from the action of the forces applied on various areas on the crown. Moreover, any lesion in the cervical area facilitates the possibility of its advance into the tooth, ultimately fracturing it. Our paper presents a FEM (finite element method study on the results of a mechanical analysis of the phenomena involving the tooth damaged by cervical lesions.

  9. Study on differences of radiosensitivity of human tooth enamel

    International Nuclear Information System (INIS)

    To study differences of radiosensitivity of human tooth enamel, 84 tooth enamel samples from 5 subjects were separated, and irradiated with radiation dose of 5 Gy from 60Co γ rays. After irradiation each sample was measured by ESR technique. Experimental results indicate that some difference in radiosensitivity exists for teeth from each subject (coefficients of variation of each subject range from 9.3% to 14.0%). Nevertheless, the mean values for all teeth of each subject among 5 subjects agree within the range of 325.77 to 386.80. It shows that the radiosensitivity of tooth enamel is basically uniform

  10. Effects of tooth profile modification on dynamic responses of a high speed gear-rotor-bearing system

    Science.gov (United States)

    Hu, Zehua; Tang, Jinyuan; Zhong, Jue; Chen, Siyu; Yan, Haiyan

    2016-08-01

    A finite element node dynamic model of a high speed gear-rotor-bearing system considering the time-varying mesh stiffness, backlash, gyroscopic effect and transmission error excitation is developed. Different tooth profile modifications are introduced into the gear pair and corresponding time-varying mesh stiffness curves are obtained. Effects of the tooth profile modification on mesh stiffness are analyzed, and the natural frequencies and mode shapes of the gear-rotor-bearing transmission system are given. The dynamic responses with respect to a wide input speed region including dynamic factor, vibration amplitude near the bearing and dynamic transmission error are obtained by introducing the time-varying mesh stiffness in different tooth profile modification cases into the gear-rotor-bearing dynamic system. Effects of the tooth profile modification on the dynamic responses are studied in detail. The numerical simulation results show that both the short profile modification and the long profile modification can affect the mutation of the mesh stiffness when the number of engaging tooth pairs changes. A short profile modification with an appropriate modification amount can improve the dynamic property of the system in certain work condition.

  11. Tooth brushing among 11- to 15-year-olds in Denmark

    DEFF Research Database (Denmark)

    Bast, L. S.; Nordahl, H.; Christensen, L. B.;

    2015-01-01

    OBJECTIVE: Regular tooth brushing in adolescence predicts stable tooth brushing habits later in life. Differences in tooth brushing habits by ethnic background and socioeconomic position have been suggested. We investigated migration status and social class in relation to infrequent tooth brushing...

  12. Three-dimensional Micro-culture System for Tooth Tissue Engineering.

    Science.gov (United States)

    Kuchler-Bopp, S; Bécavin, T; Kökten, T; Weickert, J L; Keller, L; Lesot, H; Deveaux, E; Benkirane-Jessel, N

    2016-06-01

    The arrangement of cells within a tissue plays an essential role in organogenesis, including tooth development. Progress is being made to regenerate teeth by reassociating dissociated embryonic dental cells and implanting them in vivo. In the present study, we tested the hanging drop method to study mixed epithelial-mesenchymal cell reorganization in a liquid instead of semisolid medium to see whether it could lead to tooth histogenesis and organogenesis. This method allowed the control of the proportion and number of cells to be used, and the forming microtissues showed homogeneous size. The liquid environment favored cell migrations as compared with collagen gels. Three protocols were compared. The one that sequentially combined the hanging drop and semisolid medium cultures prior to in vivo implantation gave the best results. Indeed, after implantation, teeth developed, showing a well-formed crown, mineralization of dentin and enamel, and the initiation of root formation. Vascularization and the cellular heterogeneity in the mesenchyme were similar to what was observed in developing molars. Finally, after coimplantation with a trigeminal ganglion, the dental mesenchyme, including the odontoblast layer, became innervated. The real advantage of this technique is the small number of cells required to make a tooth. This experimental model can be employed to study the development, physiology, metabolism, or toxicology in forming teeth and test other cell sources. PMID:26965424

  13. Evolution of the dragonfly head-arresting system

    OpenAIRE

    Gorb, S. N.

    1999-01-01

    The arrester or fixation system of the head in adult Odonata is unique among arthropods. This system involves the organs of two body segments: the head and the neck. It consists of a skeleton–muscle apparatus that sets the arrester parts in motion. The parts comprise formations covered with complicated microstructures: fields of microtrichia on the rear surface of the head and post-cervical sclerites of the neck. The arrester immobilizes the head during feeding or when the dragonfly is in tan...

  14. Some characteristics of the design of heads for the cutting of bevel gears with negative curvature of the circular-arc tooth line

    Science.gov (United States)

    Savinov, A. P.; Iastrebov, V. M.

    The principles of the design of the external and internal finishing cutters of heads for the machining of bevel gears with negative curvature of the circular-arc tooth line are examined. The differences between heads for the machining of circular-arc teeth with positive and negative curvatures are discussed. A newly developed design of a head for the machining of bevel gears with negative curvature of the circular-arc tooth is described as an example.

  15. Analysis of tooth decay data in Japan using asymmetric statistical models

    OpenAIRE

    Yamamoto, Kouji

    2012-01-01

    Kouji Yamamoto,1 Sadao Tomizawa21Department of Medical Innovation, Osaka University Hospital, Osaka, 2Department of Information Sciences, Faculty of Science and Technology, Tokyo University of Science, Noda City, Chiba, JapanBackground: The aim of the present paper was to develop two new asymmetry probability models to analyze data for tooth decay from 363 women and 349 men aged 18–39 years who visited a dental clinic in Sapporo City, Japan, from 2001 to 2005.Methods: We analyzed th...

  16. Single Visit Apexification Procedure of a Traumatically Injured Tooth with a Novel Bioinductive Material (Biodentine)

    OpenAIRE

    Bajwa, Navroop Kaur; Jingarwar, Mahesh Madhukar; Pathak, Anuradha

    2015-01-01

    ABSTRACT Aim of this article is to present a case wherein single visit apexification of a traumatically injured tooth was done with a bioactive material–Biodentine. An injury sustained between the ages of 6 and 14 can adversely affect pulpal health and interrupt root development. In these instances, apexification is generally the preferred treatment. A 10 years old male patient presented with coronal fracture of the left upper central incisor. Clinical and radiographic assessment showed negat...

  17. Pyruvate stabilizes electrocardiographic and hemodynamic function in pigs recovering from cardiac arrest.

    Science.gov (United States)

    Cherry, Brandon H; Nguyen, Anh Q; Hollrah, Roger A; Williams, Arthur G; Hoxha, Besim; Olivencia-Yurvati, Albert H; Mallet, Robert T

    2015-12-01

    Cardiac electromechanical dysfunction may compromise recovery of patients who are initially resuscitated from cardiac arrest, and effective treatments remain elusive. Pyruvate, a natural intermediary metabolite, energy substrate, and antioxidant, has been found to protect the heart from ischemia-reperfusion injury. This study tested the hypothesis that pyruvate-enriched resuscitation restores hemodynamic, metabolic, and electrolyte homeostasis following cardiac arrest. Forty-two Yorkshire swine underwent pacing-induced ventricular fibrillation and, after 6 min pre-intervention arrest, 4 min precordial compressions followed by transthoracic countershocks. After defibrillation and recovery of spontaneous circulation, the pigs were monitored for another 4 h. Sodium pyruvate or NaCl were infused i.v. (0.1 mmol·kg(-1)·min(-1)) throughout precordial compressions and the first 60 min recovery. In 8 of the 24 NaCl-infused swine, the first countershock converted ventricular fibrillation to pulseless electrical activity unresponsive to subsequent countershocks, but only 1 of 18 pyruvate-treated swine developed pulseless electrical activity (relative risk 0.17; 95% confidence interval 0.13-0.22). Pyruvate treatment also lowered the dosage of vasoconstrictor phenylephrine required to maintain systemic arterial pressure at 15-60 min recovery, hastened clearance of excess glucose, elevated arterial bicarbonate, and raised arterial pH; these statistically significant effects persisted up to 3 h after sodium pyruvate infusion, while infusion-induced hypernatremia subsided. These results demonstrate that pyruvate-enriched resuscitation achieves electrocardiographic and hemodynamic stability in swine during the initial recovery from cardiac arrest. Such metabolically based treatment may offer an effective strategy to support cardiac electromechanical recovery immediately after cardiac arrest. PMID:26088865

  18. Molar tooth sign − looking beyond the obvious

    Directory of Open Access Journals (Sweden)

    Nasreen Mahomed

    2013-08-01

    Full Text Available The molar tooth sign was initially identified in Joubert syndrome, named after Marie Joubert who first described it in 1968 as a rare autosomal recessive disorder characterised by the neuroradiological hallmark of the molar tooth sign caused by cerebellar vermian hypoplasia. Subsequently, it emerged that the molar tooth sign encompasses many syndromes that are now grouped together and termed Joubert syndrome and related disorders (JSRDs. Knowledge of the newer classification system and the subtypes is important and helps to direct and interpret imaging studies based on clinical signs so as to avoid delay in diagnosis of the hepatic oculorenal and renal subtypes of JSRDs in patients in whom the molar tooth sign is identified on brain MRI.

  19. Patient Discomfort Following Single-Tooth Implant Placement

    DEFF Research Database (Denmark)

    Spin-Neto, Rubens; Pontes, Ana Emília Farias; Wenzel, Ann;

    2014-01-01

    Aims: Evaluate postoperative discomfort (pain, bleeding and swelling) in single-tooth implant patients submitted to immediate or conventional tooth restoration together with assessment of treatment time. Methods: Twenty-four patients who received single-tooth maxillary dental implants were randomly...... assigned to an IR (Immediate Restoration) or CR (Conventional Restoration) group. In IR, an implant was inserted and a provisional tooth crown was delivered within the same session, while in CR it was delivered three months after implantation. Pain (first three days), bleeding (first day) and swelling...... (first seven days) were assessed using a questionnaire with Visual Analogue Scales (VAS). Results: Treatment time was longer for IR than for CR (57 ± 14 and 33 ± 8 min, respectively; ppain, bleeding, and swelling were low for both groups at the first postoperative day. VAS...

  20. Ectopic 3rd Molar Tooth in the Maxillary Antrum

    Directory of Open Access Journals (Sweden)

    Seidu A. Bello

    2014-01-01

    Full Text Available Location of ectopic tooth in a nondentate area like the maxillary antrum is rare. A 17-year-old boy, with one year history of recurrent right facial swelling and radiographic finding of a maxillary third molar tooth located at the posterior wall of the maxillary antrum, is presented. Under endotracheal intubation, the tooth was extracted through a Caldwell-Luc antrostomy approach and patient had an uneventful recovery and has been symptom free for eight months. Ectopic tooth in the maxillary antrum is rare and is commonest with maxillary third molar. It may be symptomless but is more commonly associated with inflammatory symptoms. The treatment of choice is surgical excision which is mostly carried out with Caldwell-Luc approach, even though endoscopic approach is being reported.

  1. Genetics Home Reference: Charcot-Marie-Tooth disease

    Science.gov (United States)

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions Charcot-Marie-Tooth disease Charcot- ...

  2. Retrospective individual dosimetry using EPR of tooth enamel

    International Nuclear Information System (INIS)

    The results of joint investigations (in the framework of ECP-10 program) aimed on the improvement of the sensitivity and accuracy of the procedure of dose measurement using tooth enamel EPR spectroscopy are presented. It is shown, what the sensitivity of method may be increased using special physical-chemical procedure of the enamel samples treatment, which leads to the reducing of EPR signal of organic components in enamel. Tooth diseases may have an effect on radiation sensitivity of enamel. On the basis of statistical analysis of the results of more then 2000 tooth enamel samples measurements it was shown, what tooth enamel EPR spectroscopy gives opportunity to register contribution into total dose, which is caused by natural environmental radiation and by radioactive contamination. EPR response of enamel to ultraviolet exposure is investigated and possible influences to EPR dosimetry is discussed. The correction factors for EPR dosimetry in real radiation fields are estimated

  3. Anomalies of tooth formation in hypohidrotic ectodermal dysplasia

    DEFF Research Database (Denmark)

    Lexner, Michala O; Bardow, Allan; Hertz, Jens Michael; Nielsen, Lis A; Kreiborg, Sven

    2007-01-01

    first to elaborate on anomalies of tooth formation found in a group of hemizygous males and heterozygous females with known ED1 mutations. These tooth anomalies may be used as dental biomarkers for heterozygous females, enabling an earlier diagnosis, and therefore, better treatment and genetic...... counselling. METHODS: Anomalies of tooth formation were examined using panoramic radiographs, dental casts and oral photographs in hemizygous males and heterozygous females who were identified by molecular genetic analysis. The results were compared to existing controls and normative data. RESULTS: All......, especially in the mesiodistal dimension. CONCLUSIONS: We conclude that observed anomalies of tooth formation may be used as dental biomarkers in the clinical identification of potentially heterozygous females. Udgivelsesdato: 2007-Jan...

  4. Extracorporeal membrane oxygenation for pediatric cardiac arrest.

    Science.gov (United States)

    Ryan, Jennie

    2015-02-01

    Extracorporeal cardiopulmonary resuscitation (ECPR) remains a promising treatment for pediatric patients in cardiac arrest unresponsive to traditional cardiopulmonary resuscitation. With venoarterial extracorporeal support, blood is drained from the right atrium, oxygenated through the extracorporeal circuit, and transfused back to the body, bypassing the heart and lungs. The use of artificial oxygenation and perfusion thus provides the body a period of hemodynamic stability, while allowing resolution of underlying disease processes. Survival rates for ECPR patients are higher than those for traditional cardiopulmonary resuscitation (CPR), although neurological outcomes require further investigation. The impact of duration of CPR and length of treatment with extracorporeal membrane oxygenation vary in published reports. Furthermore, current guidelines for the initiation and use of ECPR are limited and may lead to confusion about appropriate use of this support. Many ethical concerns arise with this advanced form of life support. More often than not, the dilemma is not whether to withhold ECPR, but rather when to withdraw it. Although clinicians must decide if ECPR is appropriate and when further intervention is futile, the ultimate burden of choice is left to the patient's caregivers. Offering support and guidance to the patient's family as well as the patient is essential. PMID:25639578

  5. MRI in the assessment of growth arrest

    Energy Technology Data Exchange (ETDEWEB)

    Lohman, Martina; Kivisaari, Arto; Kivisaari, Leena [Helsinki Univ. Central Hospital (Finland). Dept. of Radiology; Vehmas, Tapio [Finnish Institute of Occupational Health, Helsinki (Finland); Kallio, Pentti; Puntila, Juha [Department of Paediatric Surgery, Hospital for Children and Adolescents, University Central Hospital, Helsinki (Finland)

    2002-01-01

    Objective: To compare MRI with X-ray tomography in the assessment of bone bridges across the growth plate. Materials and methods: The investigation consisted of two parts. (1) Eleven children with 13 epiphyses suspected of physeal growth arrests were examined with conventional X-ray tomography and MRI. The bar was post-traumatic in eight children, postinfectious in two and due to a congenital, operated pes equinovarus in one. Three blinded radiologists separately evaluated the examinations retrospectively. (2) The images of four children with known physeal bars in the ankle were mixed with 36 normal examinations obtained 1-year after trauma and evaluated blindly by three radiologists. Results: In 5 of 13 epiphysis, the bony bridge was considered smaller on MRI than on X-ray tomography, in 7 of 13 it was considered equal, while it was larger only in one. The interobserver agreement (weighted kappa) was 0.8 (very good) for MRI, 0.76 (good) for X-ray tomography and 0.60 (moderate) for radiographs. The four bony bridges were easily detected on MRI. Conclusions: Compared to MRI, the size of bridges was estimated larger by tomography in about half of the patients. (orig.)

  6. Developmental changes in primary cilia in the mouse tooth germ and oral cavity.

    Science.gov (United States)

    Hisamoto, Meri; Goto, Marie; Muto, Mami; Nio-Kobayashi, Junko; Iwanaga, Toshihiko; Yokoyama, Atsuro

    2016-01-01

    The primary cilium, a sensory apparatus, functions as both a chemical and mechanical sensor to receive environmental stimuli. The present study focused on the primary cilia in the epithelialmesenchymal interaction during tooth development. We examined the localization and direction of projection of primary cilia in the tooth germ and oral cavity of mice by immunohistochemical observation. Adenylyl cyclase 3 (ACIII)-immunolabeled cilia were visible in the inner/outer enamel epithelium of molars at the fetal stage and then conspicuously developed in the odontoblast layer postnatally. The primary cilia in ameloblasts and odontoblasts-shown by the double staining of acetylated tubulin and γ-tubulin-were regularly arranged from postnatal Day12, projecting apart from each other. The periodontal ligament possessed ACIII-positive cilia, which gathered on both sides of the dentin/cement and alveolar bone in postnatal days. In the oral cavity, numerous long primary cilia immunoreactive for ACIII were condensed at subepithelial stromal cells in the oral processes in fetuses, while postnatally a small number of short cilia were dispersed throughout the stroma of the oral cavity. These findings suggest that the primary cilia showing stage- and regionspecific morphology are involved in the epithelial-mesenchymal interaction during tooth development via mechano- and/or chemoreception for growth factors. PMID:27356608

  7. Atraumatic surgical extrusion to improve tooth restorability: A clinical report.

    Science.gov (United States)

    Kelly, Robert D; Addison, Owen; Tomson, Phillip L; Krastl, Gabriel; Dietrich, Thomas

    2016-06-01

    This clinical report describes the use of an "atraumatic" vertical extraction system to facilitate the restorative treatment of a tooth that would otherwise be considered unrestorable because of subgingival caries. Minimally invasive surgical root extrusion was undertaken using the Benex extraction system, which can provide controlled tooth extrusion with minimal deformation of the bone socket. A carious endodontically treated mandibular premolar was extruded to provide routine restorative treatment and endodontic retreatment. PMID:26803176

  8. Inflammatory side effects associated with orthodontic tooth movement

    OpenAIRE

    Giannopoulou, Catherine

    2009-01-01

    Orthodontic tooth movement is induced my mechanical stimuli and facilitated by the remodeling of the periodontal ligament and alveolar bone. The remodeling activities and the ultimately tooth displacement are the consequence of an inflammatory process. Vascular and cellular changes were the first events to be recognized and described. With the advancement of research techniques an important number of inflammatory mediators, growth factors, neuropeptides and metabolites of arachidonic acid hav...

  9. Treatment of Necrotic Calcified Tooth Using Intentional Replantation Procedure

    OpenAIRE

    Nima Moradi Majd; Armita Arvin; Alireza Darvish; Sareh Aflaki; Hamed Homayouni

    2014-01-01

    Introduction. If the teeth are impacted by a chronic irritant, the pulp space possibly will undergo calcific changes that may impede access opening during root canal treatment. In such cases that conventional endodontic treatment is impossible or impractical, intentional replantation may be considered as a last solution to preserve the tooth. Methods. After failing to perform conventional root canal therapy for a necrotic calcified right mandibular second premolar, the tooth was gently extrac...

  10. DENTAL IMPLANTS: AS AN ALTERNATIVE FOR TOOTH REPLACEMENT

    OpenAIRE

    Banerjee Nandini; Singh Sushma

    2013-01-01

    A dental implant is an artificial tooth that replaces a tooth that has been taken out. Implants are natural-looking, can provide support for dentures and do not affect the teeth bordering them. They are as stable as your real teeth and protect you from the loss of jawbone, which occurs when you lose teeth. Endosseous dental implants have revolutionized the fields of implants and periodontics. During the last decade, a great deal of information has been generated concerning the effectiveness a...

  11. Interdisciplinary Treatment of a Fused Lower Premolar with Supernumerary Tooth

    OpenAIRE

    Gadimli, Cengiz; Sari, Zafer

    2011-01-01

    The objective of this report is to describe combined orthodontic and endodontic treatment of a fused mandibular premolar with supernumerary tooth. The patient was a 15 year old girl seeking orthodontic treatment for the correction of maxillary and mandibular crowding. Cephalometric examination revealed skeletally Class I relationship. The panoramic radiograph showed a fused tooth with two separate pulp chambers and two separate root canals connecting in apical third. After the endodontic trea...

  12. The Prevalence and Treatment Outcomes of Primary Tooth Injuries

    OpenAIRE

    Arikan, Volkan; Sari, Saziye; Sonmez, Hayriye

    2010-01-01

    Objectives: The aim of the present study was to evaluate the type and prevalence of primary tooth injuries, as well as their treatment and treatment outcomes, among children referred to the Department of Pedodontics at the Ankara University Faculty of Dentistry in Turkey. Methods: The study population consisted of patients applying to the department with a primary tooth injury over a period of 21 months. Fifty-one patients presented with trauma to 99 primary teeth. Clinical and radiographic e...

  13. Retrieval and reattachment of an elusive tooth fragment

    OpenAIRE

    Savita Sangwan; Shivani Mathur; Samir Dutta

    2011-01-01

    Traumatic dental injuries of uncomplicated nature are a common finding and upper central incisors are the most commonly affected teeth. Sometimes, the fractured fragment or the tooth gets embedded in the surrounding soft tissues and is often missed. There are few case reports regarding the retrieval and reattachment of tooth fragment. This report presents the case of an 8-year-old girl who came with the chief complaint of pain, irritation, and tingling sensation in the lower lip since one yea...

  14. Two Mathematical Models for Generation of Crowned Tooth Surface

    OpenAIRE

    Laszlo Kelemen; Jozsef Szente

    2014-01-01

    Gear couplings are mechanical components to connect shaft ends and eliminate the misalignments. The most important element of the gear coupling is the hub which is an external gear having crowned teeth. The crowned teeth on the hub are typically produced by hobbing. The resulting tooth surface depends on several parameters. It is influenced by the size of the hob and the feed. In this paper two mathematical models of the crowned tooth surface are introduced for the generation of the idealized...

  15. Prevalence and Indicators of Tooth Wear among Chinese Adults.

    Science.gov (United States)

    Wei, Zhao; Du, Yangge; Zhang, Jing; Tai, Baojun; Du, Minquan; Jiang, Han

    2016-01-01

    Numerous epidemiological studies have focused on the prevalence and related indicators of tooth wear. However, no sufficient studies have been conducted with Chinese adults. The purpose of this study was to assess the prevalence of tooth wear and identify related indicators among adults aged 36 to 74 years in Wuhan City, P.R. China. A cross-sectional and analytic study was conducted with 720 participants, aged 35-49 yrs and 50-74 yrs, in 2014. Each age group included 360 participants, of which 50% were males and 50% were females. All participants completed a questionnaire before examination. Tooth wear was assessed using the modified Basic Erosive Wear Examination (BEWE) index. The data were analyzed using the chi-square test and binary logistic regression analysis. The prevalence of tooth wear was 67.5% and 100% in the 35-49 and 50-74 age groups, respectively. The prevalence of dentin exposure was 64.7% and 98.3%, respectively. A significantly higher prevalence of tooth wear and dentin exposure was found in the 50-74 yr group than in the 35-49 yr group (p status, and unilateral chewing. The frequency of changing toothbrushes and the habit of drinking water during meals were associated with tooth wear. In addition, the usage of hard-bristle toothbrushes and consuming vitamin C and aspirin were found to be linked with dentin exposure. In conclusion, the prevalence of tooth wear and dentin exposure observed in Chinese adults was high, and the results revealed an association between tooth wear and socio-behavioral risk indicators. PMID:27583435

  16. Role of stretch therapy in comprehensive physical habilitation of patients with Charcot–Marie–Tooth hereditary neuropathy

    Directory of Open Access Journals (Sweden)

    N. A. Shnayder

    2015-05-01

    Full Text Available Charcot–Marie–Tooth hereditary neuropathy (Charcot–Marie–Tooth disease, CMT is the most common form of hereditary neuropathies, accompanied by sensory disorders, progressive muscle weakness with the formation of disabling contractures of the limbs. Currently, the main treatment program is effective CMT habilitation, which can prevent the development of limb deformities and thereby improve the life quality of the patient. Stretch therapy is one of the most effective methods of prevention and treatment of contractures in patients with CMT. This article provides a brief review of the literature regarding the use of stretching as physical therapy program of CMT habilitation.

  17. Corticotomy-/osteotomy-assisted tooth movement microCTs differ.

    Science.gov (United States)

    Lee, W; Karapetyan, G; Moats, R; Yamashita, D-D; Moon, H-B; Ferguson, D J; Yen, S

    2008-09-01

    Corticotomy-assisted and osteotomy-assisted tooth movement involves surgical incisions through the alveolar bone. To ascertain whether teeth move by distraction osteogenesis or by regional accelerated phenomenon (RAP), we randomly assigned 30 Sprague-Dawley rats to one of 5 experimental groups: corticotomy alone, corticotomy-assisted tooth movement, osteotomy alone, osteotomy-assisted tooth movement, or tooth movement alone. Each animal was imaged by microtomography immediately after surgery, after 21 days, and after 2 months. After 21 days, regional accelerated phenomenon was observed in the alveolar bone of the corticotomy-treated animals and distraction osteogenesis in the osteotomy-assisted tooth movement animals. Pixel count data were analyzed by nested ANOVA for 5 experimental groups, split-mouth controls, 3 levels along the root, and 5 sites per level. The most demineralized sites after 21 days differed for each of the experimental groups. Our study indicates that osteotomies and corticotomies induce different alveolar bone reactions, which can be exploited for tooth movement. PMID:18719214

  18. Corticision: A Flapless Procedure to Accelerate Tooth Movement.

    Science.gov (United States)

    Park, Young Guk

    2016-01-01

    Orthodontic tooth movement results from applied forces to the teeth evoking cellular responses in the teeth and their surrounding tissues, including the periodontal ligament, alveolar bone and gingiva. It is advantageous for the orthodontist to be well informed of the detailed process of the biological events that unfold during tooth movement, since some of these details may differ from one person to another due to biological differences such as periodontal metabolism or alveolar bone density. This led us to emphasize that orthodontics is a field of endeavor where the integration of mechanics and biology is materialized, and to affirm the fact that tooth movement is conducted in individual human beings, each composed of a unique and intricate physiological system. Biological variations may be the foundation of the differences that are frequently observed in the outcomes of orthodontic treatment in particular with reference to treatment duration between patients with similar malocclusions and who were treated identically. A wide diversity of clinical trials has been carried out to control the tissue resistance to facilitate orthodontic tooth movement, which involves biomechanical, pharmaceutical, surgical, electrical regimens or tissue engineering technology. The term 'Corticision' is a neologism which indicates 'cortical bone incision'. It is a minimally invasive periodontal procedure without flap elevation, thus accelerating tooth movement with an enhanced turnover rate of the surrounding structures. This chapter introduces the technical procedure, and the biological background of how such a minor surgical procedure can receive the accelerated tooth movement with impunity and thereby shorten the duration of treatment. PMID:26599124

  19. [Rehabilitation of Charcot-Marie-Tooth Disease].

    Science.gov (United States)

    Tajima, Fumihiro; Nakamura, Takeshi; Nishimura, Yukihide; Arakawa, Hideki; Kawasaki, Takashi; Ogawa, Takahiro; Nishiyama, Kazunari

    2016-01-01

    Charcot-Marie-Tooth disease (CMT) is one of the most commonly inherited neuromuscular diseases causing progressive muscle weakness; contracture; deformity in the feet, legs, and hands; and impairments of ambulation and handgrip. Reduced physical ability can be attributed not only to the disease but also to physical deconditioning. Previously, most physicians in the field of rehabilitation were anxious about the hypothesis of overwork weakness in CMT, and did not conduct intensive exercise programs for patients with CMT. However, recent studies have reported that progressive resistance strengthening programs for lower extremities are feasible, safe, beneficial, and improve exercise intolerance and undue fatigue in patients with CMT. Although the improvement in exercise tolerance may be partly due to the reversal of deconditioning effect of related sedentary lifestyle, progressive resistance training and physical fitness can improve walking function, activities of daily living, and subjective perception of pain and fatigue in patients with CMT. To increase the daily physical function, some studies described the potential benefits of ankle-foot orthoses (AFOs); however, no control study supported it. So far, the training programs on CMT have been dependent on the exercise programs for able-bodied individuals. To increase the effects of rehabilitation, optimal programs that combine the training protocol and AFO strategies will have to be designed for patients with CMT. PMID:26764300

  20. Relationship between tooth dimensions and malocclusion

    International Nuclear Information System (INIS)

    Objective: To observe the difference in dimension of teeth among adult females with and without malocclusion. Methods: The cross-sectional study was conducted at Dr. Ishrat-ul-Ebad Khan Institute of Oral Health Sciences, Dow University of Health Sciences, Karachi, from April 2011 to April 2013, and used non-probability consecutive sampling. Mesiodistal and buccolingual crown dimensions were measured on study casts by using digital sliding caliper in 2 groups of females. Group1 had 150 subjects with normal occlusion, while Group 2 had 234 with malocclusion. Independent t test was conducted to evaluate the difference between the dimensions of teeth of the two groups. Statistical analysis was done on SPSS version 16, and p value was considered significant at 0.05. Results: Overall, the difference between the groups showed a greater tooth dimension in the malocclusion group of population compared to the normal group, and the most significant difference was observed in the mesiodistal dimension of maxillary 2nd premolar, which was 0.9+-0.6801mm greater in dimension in the malocclusion group compared to the normal group. The least difference was observed in the buccolingual dimension of the mandibular central incisor where the malocclusion group had only 0.08+-0.5247mm larger mandibular central incisors in the buccolingual dimension compared to the normal group. Conclusion: Mesiodistal and buccolingual crown dimensions were characteristically larger in the malocclusion group. (author)

  1. Trace Elements in Human Tooth Enamel

    International Nuclear Information System (INIS)

    The trace elements are considered to play a role in the resistance of teeth to dental caries. The exact mechanism by which they act has not yet been fully established. Estimations of trace elements have been undertaken in sound human teeth. By means of activation analysis it has been possible to determine trace element concentrations in different layers of enamel in the same tooth. The concentrations of the following elements have been determined: arsenic, antimony, copper, zinc, manganese, mercury, molybdenum and vanadium. The distribution of trace elements in enamel varies from those with a narrow range, such as manganese, to those with a broad range, such as antimony. The elements present in the broad range are considered to be non-essential and their presence is thought to result from a chance incorporation into the enamel. Those in the narrow range appear to be essential trace elements and are present in amounts which do not vary unduly from other body tissues. Only manganese and zinc were found in higher concentrations in the surface layer of enamel compared with the inner layers. The importance of the concentration of trace elements on this surface layer of enamel is emphasized as this layer is the site of the first attack by the carious process. (author)

  2. Cardiac arrest upon induction of anesthesia in children with cardiomyopathy: an analysis of incidence and risk factors.

    LENUS (Irish Health Repository)

    Lynch, Johanne

    2012-02-01

    INTRODUCTION: It is thought that patients with cardiomyopathy have an increased risk of cardiac arrest on induction of anesthesia, but there is little available data. The purpose of this study was to identify the incidence and potential risk factors for cardiac arrest upon induction of anesthesia in children with cardiomyopathy in our institution. METHODS: A retrospective chart review was performed. Eligible patients included patients admitted between 1998 and 2008 with the International Statistical Classification of Disease code for cardiomyopathy (ICD-9 code 425) who underwent airway intervention for sedation or general anesthesia in the operating room, cardiac diagnostic and interventional unit (CDIU) or intensive care unit. Patients undergoing emergency airway intervention following cardiovascular collapse were excluded. For each patient, we recorded patient demographics, disease severity, anesthesia location, and anesthetic technique. RESULTS: One hundred and twenty-nine patients with cardiomyopathy underwent a total of 236 anesthetic events, and four cardiac arrests were identified. One was related to bradycardia (HR<60), two were attributed to bradycardia in association with severe hypotension (systolic blood pressure<45), and the fourth arrest was related to isolated severe hypotension. Two occurred in the operating suite and two in the CDIU. There was no resulting mortality. One patient progressed to heart transplantation. Multiple combinations of anesthetic drugs were used for induction of anesthesia. CONCLUSION: We performed a review of the last 10 years of anesthesia events in children with cardiomyopathy. We report four cardiac arrests in two patients and 236 anesthetic events (1.7%). To the best of our knowledge, this is the largest review of these patients to date but is limited by its retrospective nature. The low cardiac arrest incidence prevents the identification of risk factors and the development of a cardiac arrest risk predictive clinical

  3. Emergency Neurological Life Support: Resuscitation Following Cardiac Arrest.

    Science.gov (United States)

    Rittenberger, Jon C; Friess, Stuart; Polderman, Kees H

    2015-12-01

    Cardiac arrest is the most common cause of death in North America. Neurocritical care interventions, including targeted temperature management (TTM), have significantly improved neurological outcomes in patients successfully resuscitated from cardiac arrest. Therefore, resuscitation following cardiac arrest was chosen as an emergency neurological life support protocol. Patients remaining comatose following resuscitation from cardiac arrest should be considered for TTM. This protocol will review induction, maintenance, and re-warming phases of TTM, along with management of TTM side effects. Aggressive shivering suppression is necessary with this treatment to ensure the maintenance of a target temperature. Ancillary testing, including electrocardiography, computed tomography and/or magnetic resonance imaging of the brain, continuous electroencephalography monitoring, and correction of electrolyte, blood gas, and hematocrit changes, are also necessary to optimize outcomes. PMID:26438463

  4. [Effect of phenibut on the respiratory arrest caused by serotonin].

    Science.gov (United States)

    Tarakanov, I A; Tarasova, N N; Belova, E A; Safonov, V A

    2006-01-01

    The role of the GABAergic system in mechanisms of the respiratory arrest caused by serotonin administration was studied in anaesthetized rats. Under normal conditions, the systemic administration of serotonin (20-60 mg/kg, i.v.) resulted in drastic changes of the respiratory pattern, whereby the initial phase of increased respiratory rate was followed by the respiratory arrest. The preliminary injection of phenibut (400 mg/kg, i.p.) abolished or sharply reduced the duration of the respiratory arrest phase induced by serotonin. Bilateral vagotomy following the phenibut injection potentiated the anti-apnoesic effect of phenibut, which was evidence of the additive action of vagotomy and phenibut administration. The mechanism of apnea caused by serotonin administration is suggested to include a central GABAergic element, which is activated by phenibut so as to counteract the respiratory arrest. PMID:16579056

  5. Diacetylmorphine (heroin) body packer presenting with respiratory arrest.

    Science.gov (United States)

    Naseem, Arshad; Abbas, Shahid

    2009-04-01

    Intracorporeal concealment of illicit drugs known as 'body packing' is uncommonly reported. A body packer with swallowed capsules containing Diacetylmorphine (heroin) for smuggling purposes presented with respiratory arrest and recovered after ventilatory support and nalaxone infusion. PMID:19356347

  6. Age of the Harrison Street Beast: Electron paramagnetic resonance spectra from tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Weeks, R.A. [Vanderbilt Univ., Nashville, TN (United States). Dept. of Mechanical Engineering; Elam, J.M.; Davenport, C. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Anthropology; Bogard, J.S. [Oak Ridge National Lab., TN (United States). Life Sciences Div.

    1998-04-01

    Workers doing road reconstruction in 1993 in Fort Wayne, Indiana, uncovered remains of a large skeleton and contacted archaeologists for assessment prior to continuing work. The archaeologists excavated the remains which were located in a 19-cm thick layer of blue glay, a pedological deposit which forms from wet, anaerobic environments associated with bogs. This glay layer was located some 2 meters below the current ground level (Davenport 1996). In this paper, the authors present the results of an EPR analysis of tooth enamel (biogenic hydroxyapatite) from the Harrison Street Beast. The objectives of this study are: (1) determine an age for the specimen through EPR analysis of molar tooth enamel; (2) resolve and identify the radiation sensitive EPR spectral components; and (3) develop a provisional model for the creation of radiation-sensitive components in the EPR spectra.

  7. Management of external invasive cervical resorption of tooth with Biodentine: A case report.

    Science.gov (United States)

    Baranwal, Akash Kumar

    2016-01-01

    Invasive cervical resorption (ICR) of a tooth is relatively uncommon and the etiology is not very clear. It is sometimes misdiagnosed and can lead to improper management or tooth loss. Correct diagnosis and proper management can result in a successful outcome. The treatment should aim toward the complete suppression of all resorbing tissues and the reconstruction of resorptive defect by the placement of a suitable filling material or some biological systems. One of the most significant developments of the past decade, i.e. the operating microscope used for surgical endodontics, helps the surgeon to assess pathological changes more precisely and to remove pathological lesions with far greater precision, thus minimizing tissue damage. The aim of this article was to show the management of maxillary left central incisor diagnosed with external ICR using Biodentine under dental operatory microscope (DOM). PMID:27217649

  8. Management of external invasive cervical resorption of tooth with Biodentine: A case report

    Directory of Open Access Journals (Sweden)

    Akash Kumar Baranwal

    2016-01-01

    Full Text Available Invasive cervical resorption (ICR of a tooth is relatively uncommon and the etiology is not very clear. It is sometimes misdiagnosed and can lead to improper management or tooth loss. Correct diagnosis and proper management can result in a successful outcome. The treatment should aim toward the complete suppression of all resorbing tissues and the reconstruction of resorptive defect by the placement of a suitable filling material or some biological systems. One of the most significant developments of the past decade, i.e. the operating microscope used for surgical endodontics, helps the surgeon to assess pathological changes more precisely and to remove pathological lesions with far greater precision, thus minimizing tissue damage. The aim of this article was to show the management of maxillary left central incisor diagnosed with external ICR using Biodentine under dental operatory microscope (DOM.

  9. Management of external invasive cervical resorption of tooth with Biodentine: A case report

    Science.gov (United States)

    Baranwal, Akash Kumar

    2016-01-01

    Invasive cervical resorption (ICR) of a tooth is relatively uncommon and the etiology is not very clear. It is sometimes misdiagnosed and can lead to improper management or tooth loss. Correct diagnosis and proper management can result in a successful outcome. The treatment should aim toward the complete suppression of all resorbing tissues and the reconstruction of resorptive defect by the placement of a suitable filling material or some biological systems. One of the most significant developments of the past decade, i.e. the operating microscope used for surgical endodontics, helps the surgeon to assess pathological changes more precisely and to remove pathological lesions with far greater precision, thus minimizing tissue damage. The aim of this article was to show the management of maxillary left central incisor diagnosed with external ICR using Biodentine under dental operatory microscope (DOM). PMID:27217649

  10. Viscoplastic-dynamic analyses of small-scale fracture tests to obtain crack arrest toughness values for PTS conditions

    International Nuclear Information System (INIS)

    Reliable predictions of crack arrest at the high upper shelf toughness conditions involved in postulated pressurized thermal shock (PTS) events require procedures beyond those utilized in conventional fracture mechanics treatments. To develop such a procedure, viscoplastic-dynamic fracture mechanics finite element analyses, viscoplastic material characterization testing, and small-scale crack propagation and arrest experimentation are being combines in this research. The approach couples SwRI's viscoplastic-dynamic fracture mechanics finite element code VISCRK with experiments using duplex 4340/A533B steel compact specimens. The experiments are simulated by VISCRK computations employing the Bodner-Partom viscoplastic constitutive relation and the nonlinear fracture mechanics parameter T. The goal is to develop temperature-dependent crack arrest toughness values for A533B steel. While only room temperature KIa values have been obtained so far, these have been found to agree closely with those obtained from wide plate tests. (author)

  11. Al-Qaeda arrest casts shadow over the LHC

    CERN Multimedia

    Dacey, James

    2010-01-01

    "Cern remains on course for the imminent switch-on of the Large Hadron Collider (LHC) despite the media frenzy following the recent arrest of a physicist who had been working at the facility. The researcher in question is a 32-year-old man of Algerian descent who is expected to face trail in France - the country in which he was arrested" (0.5 page)

  12. The psychosocial outcome of anoxic brain injury following cardiac arrest

    OpenAIRE

    Wilson, Michelle

    2012-01-01

    Aim of the study The psychosocial outcome of anoxic brain injury following cardiac arrest is a relatively under researched, but clinically important area. The aim of the current study was to add to the limited existing literature exploring the psychosocial outcome for cardiac arrest survivors, but specifically explore if there is a greater impact on psychosocial outcome in individuals experiencing anoxic brain injury as a result. Methods A range of self report measures were used to c...

  13. Cardiopulmonary arrest in pregnancy with schizophrenia: a case report

    OpenAIRE

    Kudo, Takako; Kaga, Akimune; Akagi, Kozo; Iwahashi, Hideki; Makino, Hiromitsu; WATANABE, YOKO; Kawamura, Takae; Sato, Taiju; Shinozaki, Tsuyoshi; Miwa, Shinya; Okazaki, Nobuo; Kure, Shigeo; Nakae, Shingi

    2014-01-01

    Background Cardiopulmonary arrest in pregnancy has a very high maternal and fetal mortality rate. We report a case of successful maternal and neonatal survival in association with emergency cesarean section of a schizophrenic pregnant patient. To our knowledge, this is the first reported case of cardiopulmonary arrest in a pregnant woman with schizophrenia. Case presentation The parents were Japanese. The mother was 39 years old and had no history of prior pregnancy. Her admission to our hosp...

  14. Usage of Lightning Arrester Line to Feed Light Electrical Loads

    Directory of Open Access Journals (Sweden)

    Hani B. Odeh

    2009-01-01

    Full Text Available In remote areas, light loads (tens of kilowatts are scattered and situated in the field of high voltage lines (66KV and above. These loads are very far from the main feeders/sub-stations (33KV-0.380KV. Feeding such loads in the traditional ways like provision of Diesel-Powered Stations, installation of new distribution lines from the Feeding Centers, or building new Sub-Stations are not practical ways from the economical point of view, because it requires huge additional expenses and will increase electrical power losses. These expenses are not worthy for such loads and therefore, it is necessary to search for other methods to supply them. One of these methods is to use the lightning arrester line as capacitive divider to supply the light loads. In this research, the induced voltage of the lightning arrester line was calculated when it is isolated from the earth. We found the capacitance between lightning arrester line versus the phases and lightning arrester. It was also found the selective power out of the lightning arrester line and the required length which is to be isolated from the earth keeping the main function of the lightning arrester line. When economically comparing between supplying the light electrical loads by traditional ways and the method of lightning arrester, it was found the advantage of using lightning arresters to supply such loads. Also, by using the traditional methods, it was noted that there is a power loss in the power transmission lines by a percentage of 1.8%.

  15. The stringent response and cell cycle arrest in Escherichia coli.

    OpenAIRE

    Daniel J Ferullo; Lovett, Susan T.

    2008-01-01

    The bacterial stringent response, triggered by nutritional deprivation, causes an accumulation of the signaling nucleotides pppGpp and ppGpp. We characterize the replication arrest that occurs during the stringent response in Escherichia coli. Wild type cells undergo a RelA-dependent arrest after treatment with serine hydroxamate to contain an integer number of chromosomes and a replication origin-to-terminus ratio of 1. The growth rate prior to starvation determines the number of chromosomes...

  16. The Stringent Response and Cell Cycle Arrest in Escherichia coli

    OpenAIRE

    Daniel J Ferullo; Lovett, Susan T.

    2008-01-01

    The bacterial stringent response, triggered by nutritional deprivation, causes an accumulation of the signaling nucleotides pppGpp and ppGpp. We characterize the replication arrest that occurs during the stringent response in Escherichia coli. Wild type cells undergo a RelA-dependent arrest after treatment with serine hydroxamate to contain an integer number of chromosomes and a replication origin-to-terminus ratio of 1. The growth rate prior to starvation determines the number of chromosomes...

  17. Dynamic propagation and cleavage crack arrest in bainitic steel

    International Nuclear Information System (INIS)

    In complement of the studies of harmfulness of defects, generally realized in term of initiation, the concept of crack arrest could be used as complementary analyses to the studies of safety. The stop occurs when the stress intensity factor becomes lower than crack arrest toughness (KIa) calculated in elasto-statics (KI ≤ KIa). The aim of this thesis is to understand and predict the stop of a crack propagating at high speed in a 18MND5 steel used in the pressure water reactor (PWR). The test chosen to study crack arrest is the disc thermal shock test. The observations under the scanning electron microscope of the fracture surface showed that the crack arrest always occurs in cleavage mode and that the critical microstructural entity with respect to the propagation and crack arrest corresponds to at least the size of the prior austenitic grain. The numerical analyses in elasto-statics confirm the conservatism of the codified curve of the RCC-M with respect to the values of KIa. The dynamic numerical analyses show that the deceleration of the crack measured at the end of the propagation is related to the global dynamic of the structure (vibrations). The transferability to components of crack arrest toughness obtained from tests analysed in static is thus not assured. The disc thermal shock tests were also modelled by considering a criterion of propagation and arrest of the type 'RKR' characterized by a critical stress sc which depends on the temperature. The results obtained account well for the crack jump measured in experiments as well as the shape of the crack arrest front. (author)

  18. Comparison of the effect of thermal stresses on tooth-colored posts, cores and tooth structures by finite element analysis

    OpenAIRE

    Levent Nalbant; Ferhan Egilmez

    2012-01-01

    Objectives: The aims of this study were to analyze the influence of cold heat flow in all ceramic crown material, composite core, zirconium and glass fiber reinforced composite post materials, resin based luting cement and root dentin; and to compare these two tooth-colored post systems about their temperature and thermal stress distributions.
    Materials and Methods: A 3-dimesional finite element model of maxillary left canine tooth was constructed. All ceramic crown, composite cor...

  19. In Vitro Spectrophotometry of Tooth Discoloration Induced by Tooth-Colored Mineral Trioxide Aggregate and Calcium-Enriched Mixture Cement

    OpenAIRE

    Arman, Marjan; Khalilak, Zohreh; Rajabi, Moones; Esnaashari, Ehsan; Saati, Keyvan

    2015-01-01

    Introduction: There are numerous factors that can lead to tooth discoloration after endodontic treatment, such as penetration of endodontic materials into the dentinal tubules during root canal treatment. The aim of this in vitro study was to compare discoloration induced by tooth colored mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement in extracted human teeth. Methods and Materials: Thirty two dentin-enamel cuboid blocks (7×7×2 mm) were prepared from extracted maxi...

  20. Use of ultrasound Doppler to determine tooth vitality in a discolored tooth after traumatic injury: its prospects and limitations

    OpenAIRE

    Cho, Yong-Wook; Park, Sung-Ho

    2014-01-01

    When a tooth shows discoloration and does not respond to the cold test or electric pulp test (EPT) after a traumatic injury, its diagnosis can be even more difficult due to the lack of proper diagnostic methods to evaluate its vitality. In these case reports, we hope to demonstrate that ultrasound Doppler might be successfully used to evaluate the vitality of the tooth after trauma, and help reduce unnecessary endodontic treatments. In all three of the present cases, the teeth were discolored...

  1. Tooth model reconstruction based upon data fusion for orthodontic treatment simulation.

    Science.gov (United States)

    Yau, Hong-Tzong; Yang, Tsan-Jui; Chen, Yi-Chen

    2014-05-01

    This paper proposes a full tooth reconstruction method by integrating 3D scanner data and computed tomography (CT) image sets. In traditional dental treatment, plaster models are used to record patient׳s oral information and assist dentists for diagnoses. However, plaster models only save surface information, and are therefore unable to provide further information for clinical treatment. With the rapid development of medical imaging technology, computed tomography images have become very popular in dental treatment. Computed tomography images with complete internal information can assist the clinical diagnosis for dental implants or orthodontic treatment, and a digital dental model can be used to simulate and predict results before treatment. However, a method of producing a high quality and precise dental model has yet to be developed. To this end, this paper presents a tooth reconstruction method based on the data fusion concept via integrating external scanned data and CT-based medical images. First, a plaster model is digitized with a 3D scanner. Then, each crown can be separated from the base according to the characteristics of tooth. CT images must be processed for feature enhancement and noise reduction, and to define the tooth axis direction which will be used for root slicing. The outline of each slice of dental root can then be determined by the level set algorithm, and converted to point cloud data. Finally, the crown and root data can be registered by the iterative closest point (ICP) algorithm. With this information, a complete digital dental model can be reconstructed by the Delaunay-based region-growing (DBRG) algorithm. The main contribution of this paper is to reconstruct a high quality customized dental model with root information that can offer significant help to the planning of dental implant and orthodontic treatment. PMID:24631784

  2. Does Timing of Eruption in First Primary Tooth Correlate with that of First Permanent Tooth? A 9-years Cohort Study

    Science.gov (United States)

    Poureslami, Hamidreza; Asl Aminabadi, Naser; Sighari Deljavan, Alireza; Erfanparast, Leila; Sohrabi, Azin; Jamali, Zahra; Ghertasi Oskouei, Sina; Hazem, Kameliya; Shirazi, Sajjad

    2015-01-01

    Background and aims. Predicting the teeth eruption time is a valuable tool in pediatric dentistry since it can affects scheduling dental and orthodontic treatments. This study investigated the relationship between the eruption time of first primary and permanent teeth and the variation in the eruption time considering socioeconomic status (SES) in a 9-year population- based cohort study. Materials and methods. 307 subjects were examined at bimonthly intervals during the first and second years of life and then at six-month intervals until the eruption of first permanent tooth. Eruption times of primary and permanent tooth were recorded for each child. A modified form of Kuppuswamy’s scale was used to assess the SES. Results. Among 267 subjects completed all follow-ups, the eruption time for first primary and permanent teeth indicated a direct strong correlation; in that one month delayed or early eruption of firstprimary tooth resulted in 4.21 months delayed or early eruption of first appearing permanent tooth (r = 0.91, n = 267, P <0.001). No significant correlation was observed between the eruption time of first primary and first permanent teeth and SES (P = 0.67, P = 0.75, respectively). Conclusion. The eruption timing for the first primary tooth had a correlation with the first permanent tooth eruption tim-ing, while SES did not have any influence on eruption times. PMID:26236432

  3. METHODS TO VALIDATE TOOTH-SUPPORTING REGENERATIVE THERAPIES

    Science.gov (United States)

    Padial-Molina, Miguel; Marchesan, Julie T.; Taut, Andrei D.; Jin, Qiming; Giannobile, William V.; Rios, Hector F.

    2012-01-01

    SUMMARY In humans, microbially-induced inflammatory periodontal diseases are the primary initiators that disrupt the functional and structural integrity of the periodontium (i.e., the alveolar bone, the periodontal ligament, and the cementum). The re-establishment of its original structure, properties and function constitutes a significant challenge in the development of new therapies to regenerate tooth-supporting defects. Preclinical models represent an important in vivo tool to critically evaluate and analyze key aspects of novel regenerative therapies including: 1) Safety, 2) Effectiveness, 3) Practicality, and 4) Functional and structural stability over time. Therefore, these models provide foundational data that supports the clinical validation and the development of novel innovative regenerative periodontal technologies. Steps are provided on the use of the root fenestration animal model for the proper evaluation of periodontal outcome measures using the following parameters: descriptive histology, histomorphometry, immunostaining techniques, three-dimensional imaging, electron microscopy, gene expression analyses and safety assessments. These methods will prepare investigators and assist them in identifying key endpoints that can then be adapted to later stage human clinical trials. PMID:22566053

  4. Origin and developmental fate of vestigial tooth primordia in the upper diastema of the field vole (Microtus agrestis, Rodentia)

    Czech Academy of Sciences Publication Activity Database

    Witter, K.; Lesot, H.; Peterka, Miroslav; Vonesch, J. L.; Míšek, Ivan; Peterková, Renata

    2005-01-01

    Roč. 50, - (2005), s. 401-409. ISSN 0003-9969 R&D Projects: GA MŠk OC B23.001; GA ČR GA304/02/0448 Institutional research plan: CEZ:AV0Z50390512 Keywords : tooth development * odontogenesis * embryo Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.288, year: 2005

  5. The complex oring of a tooth can cause its developmental vulnerability and explain the formation of supernumeraries

    Czech Academy of Sciences Publication Activity Database

    Hovořáková, Mária; Lesot, H.; Peterková, Renata; Peterka, Miroslav

    -, - (2006), s. 51-51. [Growth Factors in Craniofacial Development and Repair. 04.05.2006-07.05.2006, Helsinki] R&D Projects: GA MŠk OC B23.002; GA ČR GA304/05/2665 Institutional research plan: CEZ:AV0Z50390512 Keywords : Supernumerary tooth * Man * Mouse Subject RIV: EB - Genetics ; Molecular Biology

  6. Three-dimensional Finite Element Analysis of the Mechanical Stress on Root from Orthodontic Tooth Movement by Sliding Mechanics

    Institute of Scientific and Technical Information of China (English)

    LI Ping; MAO Jing; PENG Zhou; XIE Hui

    2007-01-01

    In order to study mechanical stress on root from orthodontic tooth movement by sliding mechanics, a 3-dimensional finite element model incorporating all layers of a human mandibular dental arch with orthodontic appliance has been developed to simulate mechanical stress on root from the orthodontic tooth movement. Simulated orthodontic force of 2 N at 0, 30 and 45 degree from the horizontal axis was applied to the crown of the teeth. The finite element analysis showed when or- thodontic forces were applied to the tooth, the stress was mainly concentrated at the neck of the tooth decreasing uniformly to the apex and crown. The highest stress on the root was 0.621 N/ram2 for cer- vical margin of the canine, and 0.114 N/mm2 for apical region of the canine. The top of canine crown showed the largest amount of displacement (2.417 μm), while the lowest amount of displacement was located at the apical region of canine (0.043 μm). In conclusion, this model might enable one to simulate orthodontic tooth movements clinically. Sliding force at 2 N is ideal to ensure the bodily or- thodontic tooth movement. The highest stress concentration in the roots was always localized at the cervical margin when orthodontic force of 2 N at 0, 30 and 45 degree from the horizontal axis, so there may be the same risk of root resorption when orthodontic force of 2 N at 0, 30 and 45 degree was used in clinic cases.

  7. Situational ambiguity and gendered patterns of arrest for intimate partner violence.

    Science.gov (United States)

    Durfee, Alesha

    2012-01-01

    Using data from the 2005 National Incident-Based Reporting System (NIBRS), this analysis focuses on the impacts that domestic violence mandatory arrest policies have on arrest outcomes in "situationally ambiguous" cases: cases where both the female and male partners have been identified by police as both a victim and an offender. Results indicate that although officers arrest male partners more frequently than female partners, after controlling for incident and individual factors, mandatory arrest policies disproportionately affect women. Furthermore, correlates of arrest differ for male-only arrests versus female-only arrests. These findings are discussed in the context of changing legal responses to domestic violence. PMID:22411299

  8. Anterior tooth relations in Kenyan Africans.

    Science.gov (United States)

    Hassanali, J; Pokhariyal, G P

    1993-04-01

    Dental plaster casts of 235 Maasai, 116 Kikuyu and 61 Kalenjin children aged 3-16 yr were studied to determine the incidence and magnitude of diastemas, overbite, overjet and anterior open bite. The highest prevalence of diastema was amongst the Maasai (61.3%), of overbite (84%) and overjet (99%) amongst the Kikuyu, and of anterior open bite amongst Kalenjin (24%), with values greater than 0.4 mm up to 11.5 mm. Comparison of the mean values showed that diastema (1.77 mm) and overjet (4.4 mm) were greatest in Maasai, overbite (3.53 mm) in Kalenjin, and anterior open bite (3.50 mm) in Kikuyu. In the total sample, the prevalence and mean of diastema were 49%, 1.68 mm; of overbite 77.4%, 2.96 mm; of overjet 88.6%, 3.83 mm; and of anterior open bite 16.5%, 2.69 mm (with values between 0.4-11.5 mm), while 5.5% had an edge-to-edge bite (-0.5-0.5 mm). The prevalence of diastema decreased whilst its magnitude increased with age. The mean values of overbite and overjet increased, while those for anterior open bite decreased with age. The mean values of diastema, overbite and overjet were greater amongst the females, but the difference was significant only for overjet. The high prevalence and greater values of measurements of anterior tooth relations may be related to variable growth of the bimaxillary dentoalveolar complex and soft tissue influences. This may be important in orthodontic treatment planning, dental prostheses and other clinical dental treatments in Kenyan populations. PMID:8517805

  9. Gearbox Tooth Cut Fault Diagnostics Using Acoustic Emission and Vibration Sensors — A Comparative Study

    Directory of Open Access Journals (Sweden)

    Yongzhi Qu

    2014-01-01

    Full Text Available In recent years, acoustic emission (AE sensors and AE-based techniques have been developed and tested for gearbox fault diagnosis. In general, AE-based techniques require much higher sampling rates than vibration analysis-based techniques for gearbox fault diagnosis. Therefore, it is questionable whether an AE-based technique would give a better or at least the same performance as the vibration analysis-based techniques using the same sampling rate. To answer the question, this paper presents a comparative study for gearbox tooth damage level diagnostics using AE and vibration measurements, the first known attempt to compare the gearbox fault diagnostic performance of AE- and vibration analysis-based approaches using the same sampling rate. Partial tooth cut faults are seeded in a gearbox test rig and experimentally tested in a laboratory. Results have shown that the AE-based approach has the potential to differentiate gear tooth damage levels in comparison with the vibration-based approach. While vibration signals are easily affected by mechanical resonance, the AE signals show more stable performance.

  10. Bioactive Polymeric Composites for Tooth Mineral Regeneration: Physicochemical and Cellular Aspects

    Directory of Open Access Journals (Sweden)

    Joseph M. Antonucci

    2011-09-01

    Full Text Available Our studies of amorphous calcium phosphate (ACP-based dental materials are focused on the design of bioactive, non-degradable, biocompatible, polymeric composites derived from acrylic monomer systems and ACP by photochemical or chemically activated polymerization. Their intended uses include remineralizing bases/liners, orthodontic adhesives and/or endodontic sealers. The bioactivity of these materials originates from the propensity of ACP, once exposed to oral fluids, to release Ca and PO4 ions (building blocks of tooth and bone mineral in a sustained manner while spontaneously converting to thermodynamically stable apatite. As a result of ACP’s bioactivity, local Ca- and PO4-enriched environments are created with supersaturation conditions favorable for the regeneration of tooth mineral lost to decay or wear. Besides its applicative purpose, our research also seeks to expand the fundamental knowledge base of structure-composition-property relationships existing in these complex systems and identify the mechanisms that govern filler/polymer and composite/tooth interfacial phenomena. In addition to an extensive physicochemical evaluation, we also assess the leachability of the unreacted monomers and in vitro cellular responses to these types of dental materials. The systematic physicochemical and cellular assessments presented in this study typically provide model materials suitable for further animal and/or clinical testing. In addition to their potential dental clinical value, these studies suggest the future development of calcium phosphate-based biomaterials based on composite materials derived from biodegradable polymers and ACP, and designed primarily for general bone tissue regeneration.

  11. Photogrammetry-Based Automated Measurements for Tooth Shape and Occlusion Analysis

    Science.gov (United States)

    Knyaz, V. A.; Gaboutchian, A. V.

    2016-06-01

    Tooth measurements (odontometry) are performed for various scientific and practical applications, including dentistry. Present-day techniques are being increasingly based on 3D model use that provides wider prospects in comparison to measurements on real objects: teeth or their plaster copies. The main advantages emerge through application of new measurement methods which provide the needed degree of non-invasiveness, precision, convenience and details. Tooth measurements have been always regarded as a time-consuming research, even more so with use of new methods due to their wider opportunities. This is where automation becomes essential for further development and implication of measurement techniques. In our research automation in obtaining 3D models and automation of measurements provided essential data that was analysed to suggest recommendations for tooth preparation - one of the most responsible clinical procedures in prosthetic dentistry - within a comparatively short period of time. The original photogrammetric 3D reconstruction system allows to generate 3D models of dental arches, reproduce their closure, or occlusion, and to perform a set of standard measurement in automated mode.

  12. Vestigial tooth anatomy and tusk nomenclature for monodon monoceros.

    Science.gov (United States)

    Nweeia, Martin T; Eichmiller, Frederick C; Hauschka, Peter V; Tyler, Ethan; Mead, James G; Potter, Charles W; Angnatsiak, David P; Richard, Pierre R; Orr, Jack R; Black, Sandie R

    2012-06-01

    Narwhal tusks, although well described and characterized within publications, are clouded by contradictory references, which refer to them as both incisors and canines. Vestigial teeth are briefly mentioned in the scientific literature with limited descriptions and no image renderings. This study first examines narwhal maxillary osteoanatomy to determine whether the erupted tusks are best described as incisiform or caniniform teeth. The study also offers evidence to support the evolutionary obsolescence of the vestigial teeth through anatomic, morphologic, and histologic descriptions. Examination of 131 skull samples, including 110 museum skull specimens and 21 harvested skulls, revealed the erupted tusks surrounded by maxillary bone over the entire length of their bone socket insertion, and are thus more accurately termed caniniform or canine teeth. The anatomy, morphology, and development of vestigial teeth in five skull samples are more fully described and documented. Vestigial tooth samples included 14 embedded pairs or individual teeth that were partially exposed or removed from the maxillary bone. Their location was posterior, ventral, and lateral to the tusks, although male vestigial teeth often exfoliate in the mouth lodging between the palatal tissue and underlying maxillary bone. Their myriad morphologies, sizes, and eruption patterns suggest that these teeth are no longer guided by function but rather by random germ cell differentiation and may eventually cease expression entirely. The conclusions reached are that the narwhal tusks are the expression of canine teeth and that vestigial teeth have no apparent functional characteristics and are following a pattern consistent with evolutionary obsolescence. PMID:22467529

  13. How is sound conducted to the cochlea in toothed whales?

    Science.gov (United States)

    Zosuls, Aleks; Mountain, David C.; Ketten, Darlene R.

    2015-12-01

    Toothed whales (Odontocetes) typically have small occluded ear canals and sea water has a characteristic impedance that is much more similar to the impedance of soft tissues of the head than is the case for the air-tissue interface in terrestrial mammals. This makes it plausible that significant acoustic energy is being transmitted to their middle ear by tissue conduction. In addition, some authors have proposed that sound reaches the cochlea via bone conduction rather than via the tympanic membrane. To address these issues, we have developed a method to measure stapes velocity in response to vibrational stimulation at arbitrary locations on heads and ears harvested from stranded animals. Stapes velocity was measured with a Laser Doppler Velocimeter at the footplate with the cochlea drained. In all species tested, the transfer function of stapes velocity referenced to actuator velocity showed a high-pass characteristic. The corner frequency varied with species and experiment between 4 kHz and 60 kHz. This is similar to what is seen in odontocete audiograms but the cutoff slope is typically steeper than in the audiograms. There was no indication of high frequency cutoff within our measurement range. Disrupting the ossicles and fat bodies affected the transfer functions.

  14. Case series: CT scan in cardiac arrest and imminent cardiogenic shock

    International Nuclear Information System (INIS)

    Imaging a patient having a cardiac arrest on the examination table is not a common occurrence. Altered hemodynamics resulting from pump failure causes stasis of blood in the dependent organs of the body, which is manifested on imaging by dependent contrast pooling and layering. Often a patient with imminent cardiogenic shock also shows a similar dependent contrast pooling and layering, which is a marker of the worsening clinical condition. We report the contrast-enhanced CT scan features in four cases, two of whom had cardiac arrest during imaging, while the other two developed cardiogenic shock soon after the examination. Dependent contrast pooling and layering were found in all of them, with faint or no opacification of the left cardiac chambers. Contrast pooling was noted in the dependent lumbar veins, hepatic veins, hepatic parenchyma, and the right renal vein, as well as in the dependent part of the IVC and the right heart chambers

  15. Directed percolation identified as equilibrium pre-transition towards non-equilibrium arrested gel states

    Science.gov (United States)

    Laurati, Marco; Capellmann, Ronja; Kohl, Matthias; Egelhaaf, Stefan; Schmiedeberg, Michael

    The macroscopic properties of gels arise from their slow dynamics and load bearing network structure, which are exploited by nature and in numerous industrial products. However, a link between these structural and dynamical properties has remained elusive. Here we present confocal microscopy exper- iments and simulations of gel-forming colloid-polymer mixtures with competing interactions. They reveal that gel formation is preceded by continuous and directed percolation. Both transitions lead to system spanning networks, but only directed percolation results in extremely slow dynamics, ageing and a shrinking of the gel that resembles syneresis. Therefore, dynamical arrest in gels is found to be linked to a structural transition, namely directed percolation, which is quantitatively associated with the mean number of bonded neighbours. Directed percolation is a universality class of transitions out of equilibrium, our study hence connects gel formation to a well-developed theoretical framework which now can be exploited to achieve a detailed understanding of arrested gels.

  16. Directed percolation identified as equilibrium pre-transition towards non-equilibrium arrested gel states

    Science.gov (United States)

    Kohl, M.; Capellmann, R. F.; Laurati, M.; Egelhaaf, S. U.; Schmiedeberg, M.

    2016-06-01

    The macroscopic properties of gels arise from their slow dynamics and load-bearing network structure, which are exploited by nature and in numerous industrial products. However, a link between these structural and dynamical properties has remained elusive. Here we present confocal microscopy experiments and simulations of gel-forming colloid-polymer mixtures. They reveal that gel formation is preceded by continuous and directed percolation. Both transitions lead to system-spanning networks, but only directed percolation results in extremely slow dynamics, ageing and a shrinking of the gel that resembles synaeresis. Therefore, dynamical arrest in gels is found to be linked to a structural transition, namely directed percolation, which is quantitatively associated with the mean number of bonded neighbours. Directed percolation denotes a universality class of transitions. Our study hence connects gel formation to a well-developed theoretical framework, which now can be exploited to achieve a detailed understanding of arrested gels.

  17. Nursing students’ knowledge about arrest rhythms and their treatment

    Directory of Open Access Journals (Sweden)

    Aikaterini Kyrgianidou

    2014-04-01

    Full Text Available Cardiovascular diseases are one of the leading causes of death worldwide. Knowledge of health professionals for the arrest rhythms, is considered particularly important for the early recognition and proper treatment. Aim: The purpose of the present study was to assess the knowledge of nursing students on arrest rhythms and how to treat them. Material and Methods: The sample studied included 151 students from the Department of Nursing A' (n = 60, 40% and B' (n = 91, 60%, TEI of Athens, of whom 83% (n=125 were women and 17% (n=26 were men with a mean age of 23 years. Data collection was performed with specially designed questionnaire, that apart from demographics and students’ education level, it included ten questions about arrest rhythms’ knowledge and also self-assessment questions of their level of knowledge. The data were analyzed with the SPSS package v.19, using the criteria t-Test and χ2. Results: Of all the participants in the research, 95% (n = 144 did not answer correctly more than 6 questions from a total of 10. The students of the Department of Nursing A’ recognized with greater accuracy the arrest rhythms (p = 0.003. Those studying in lower semester acknowledged best the arrest rhythms (p = 0.002. Students who had recently attended course in basic or advanced resuscitation recognized best the arrest rhythms (p = 0.006. Older students knew better right treatment of the arrest rhythms (p = 0.037. Also, students who had attended the course of cardiac nursing in the last year, knew better the right treatment (p <0.001. Finally, the level of self-assessment was in line with the actual level of knowledge of students (p = 0.05. Conclusions: Continuous attendance of courses, education on certified programs and refresh courses help to maintain a good level of knowledge for longer periods.

  18. The stringent response and cell cycle arrest in Escherichia coli.

    Science.gov (United States)

    Ferullo, Daniel J; Lovett, Susan T

    2008-12-01

    The bacterial stringent response, triggered by nutritional deprivation, causes an accumulation of the signaling nucleotides pppGpp and ppGpp. We characterize the replication arrest that occurs during the stringent response in Escherichia coli. Wild type cells undergo a RelA-dependent arrest after treatment with serine hydroxamate to contain an integer number of chromosomes and a replication origin-to-terminus ratio of 1. The growth rate prior to starvation determines the number of chromosomes upon arrest. Nucleoids of these cells are decondensed; in the absence of the ability to synthesize ppGpp, nucleoids become highly condensed, similar to that seen after treatment with the translational inhibitor chloramphenicol. After induction of the stringent response, while regions corresponding to the origins of replication segregate, the termini remain colocalized in wild-type cells. In contrast, cells arrested by rifampicin and cephalexin do not show colocalized termini, suggesting that the stringent response arrests chromosome segregation at a specific point. Release from starvation causes rapid nucleoid reorganization, chromosome segregation, and resumption of replication. Arrest of replication and inhibition of colony formation by ppGpp accumulation is relieved in seqA and dam mutants, although other aspects of the stringent response appear to be intact. We propose that DNA methylation and SeqA binding to non-origin loci is necessary to enforce a full stringent arrest, affecting both initiation of replication and chromosome segregation. This is the first indication that bacterial chromosome segregation, whose mechanism is not understood, is a step that may be regulated in response to environmental conditions. PMID:19079575

  19. The stringent response and cell cycle arrest in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Daniel J Ferullo

    2008-12-01

    Full Text Available The bacterial stringent response, triggered by nutritional deprivation, causes an accumulation of the signaling nucleotides pppGpp and ppGpp. We characterize the replication arrest that occurs during the stringent response in Escherichia coli. Wild type cells undergo a RelA-dependent arrest after treatment with serine hydroxamate to contain an integer number of chromosomes and a replication origin-to-terminus ratio of 1. The growth rate prior to starvation determines the number of chromosomes upon arrest. Nucleoids of these cells are decondensed; in the absence of the ability to synthesize ppGpp, nucleoids become highly condensed, similar to that seen after treatment with the translational inhibitor chloramphenicol. After induction of the stringent response, while regions corresponding to the origins of replication segregate, the termini remain colocalized in wild-type cells. In contrast, cells arrested by rifampicin and cephalexin do not show colocalized termini, suggesting that the stringent response arrests chromosome segregation at a specific point. Release from starvation causes rapid nucleoid reorganization, chromosome segregation, and resumption of replication. Arrest of replication and inhibition of colony formation by ppGpp accumulation is relieved in seqA and dam mutants, although other aspects of the stringent response appear to be intact. We propose that DNA methylation and SeqA binding to non-origin loci is necessary to enforce a full stringent arrest, affecting both initiation of replication and chromosome segregation. This is the first indication that bacterial chromosome segregation, whose mechanism is not understood, is a step that may be regulated in response to environmental conditions.

  20. Comparative clinical evaluation of two professional tooth-whitening products.

    Science.gov (United States)

    Kowitz, G M; Nathoo, S A; Wong, R

    1994-01-01

    A 2-week study was conducted to compare the tooth-whitening efficacy of two 10% carbamide peroxide products: Colgate Platinum Professional Toothwhitening System and Rembrandt Lighten Bleaching Gel. Fifty subjects were divided into two groups and assigned a product to use for 2 weeks. Change in tooth color was measured by reflectance spectroscopy at the initiation of study, at 1 week, and at 2 weeks into the study. Color change was calculated using the color-difference equation established by the Commission International de L'Eclairage. Results showed that Colgate Platinum was 62% more effective at tooth whitening after 1 week and 83% more effective after 2 weeks of treatment vs Rembrandt. At the termination of the study, the mean color difference (deltaE) for Colgate Platinum was 4.29 and 2.34 for Rembrandt. Statistical analysis demonstrated that the Colgate product is significantly superior at increasing tooth whiteness, increasing tooth lightness, reducing redness, and reducing yellowness. In this study, no adverse reactions were noted on clinical examination and none were reported by panelists with normal healthy dentition. PMID:8205580