WorldWideScience

Sample records for human dental tissues

  1. Regulatory roles of microRNAs in human dental tissues.

    Science.gov (United States)

    Sehic, Amer; Tulek, Amela; Khuu, Cuong; Nirvani, Minou; Sand, Lars Peter; Utheim, Tor Paaske

    2017-01-05

    MicroRNAs (miRNAs) are a class of small, non-coding RNAs that provide an efficient pathway for regulation of gene expression at a post-transcriptional level. Tooth development is regulated by a complex network of cell-cell signaling during all steps of organogenesis. Most of the congenital dental defects in humans are caused by mutations in genes involved in developmental regulatory networks. Whereas the developmental morphological stages of the tooth development already are thoroughly documented, the implicated genetic network is still under investigation. The involvement of miRNAs in the regulation of tooth genetic network was suggested for the first time in 2008. MiRNAs regulate tooth morphogenesis by fine-tuning the signaling networks. Unique groups of miRNAs are expressed in dental epithelium compared with mesenchyme, as well as in molars compared with incisors. The present review focuses on the current state of knowledge on the expression and function of miRNAs in human dental tissues, including teeth and the surrounding structures. Herein, we show that miRNAs exhibit specific roles in human dental tissues and are involved in gingival and periodontal disease, tooth movement and eruption, dental pulp physiology including repair and regeneration, differentiation of dental cells, and enamel mineralization. In light of similarities between the tooth development and other organs originating from the epithelium, further understanding of miRNAs` function in dental tissues may have wide biological relevance. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Activation of the NLRP3/caspase-1 inflammasome in human dental pulp tissue and human dental pulp fibroblasts.

    Science.gov (United States)

    Jiang, Wenkai; Lv, Haipeng; Wang, Haijing; Wang, Diya; Sun, Shukai; Jia, Qian; Wang, Peina; Song, Bing; Ni, Longxing

    2015-08-01

    The NLRP3/caspase-1 inflammasome pathway plays an important role in cellular immune defence against bacterial infection; however, its function in human dental pulp tissue and human dental pulp fibroblasts remains poorly understood. We demonstrate that NLRP3 protein expression occurs to a greater extent in pulp tissue with irreversible pulpitis than in normal pulp tissue and in tissue with reversible pulpitis. Caspase-1 is present in its active (cleaved) form only in pulp tissue with irreversible pulpitis. NLRP3 and caspase-1 are expressed in the odontoblast layers in normal human dental pulp tissue, whereas in inflamed pulp tissue, the odontoblast layers are disrupted and dental pulp cells are positive for NLRP3 and caspase-1. Additionally, we investigate the role of the NLRP3/caspase-1 inflammasome pathway in human dental pulp fibroblasts and show that ATP activates the P2X7 receptor on the cell membrane triggering K(+) efflux and inducing the gradual recruitment of the membrane pore pannexin-1. Extracellular lipopolysaccharide is able to penetrate the cytosol and activate NLRP3. Furthermore, the low intracellular K(+) concentration in the cytosol triggers reactive oxygen species generation, which also induces the NLRP3 inflammasome. Thus, the NLRP3/caspase-1 pathway has a biological role in the innate immune response mounted by human dental pulp fibroblasts.

  3. Concise reviews: Characteristics and potential applications of human dental tissue-derived mesenchymal stem cells.

    Science.gov (United States)

    Liu, Junjun; Yu, Fang; Sun, Yao; Jiang, Beizhan; Zhang, Wenjun; Yang, Jianhua; Xu, Guo-Tong; Liang, Aibin; Liu, Shangfeng

    2015-03-01

    Recently, numerous types of human dental tissue-derived mesenchymal stem cells (MSCs) have been isolated and characterized, including dental pulp stem cells, stem cells from exfoliated deciduous teeth, periodontal ligament stem cells, dental follicle progenitor cells, alveolar bone-derived MSCs, stem cells from apical papilla, tooth germ progenitor cells, and gingival MSCs. All these MSC-like cells exhibit self-renewal, multilineage differentiation potential, and immunomodulatory properties. Several studies have demonstrated the potential advantages of dental stem cell-based approaches for regenerative treatments and immunotherapies. This review outlines the properties of various dental MSC-like populations and the progress toward their use in regenerative therapy. Several dental stem cell banks worldwide are also introduced, with a view toward future clinical application. © 2014 AlphaMed Press.

  4. Comparison of human dental follicle cells and human periodontal ligament cells for dentin tissue regeneration.

    Science.gov (United States)

    Tian, Ye; Bai, Ding; Guo, Weihua; Li, Jie; Zeng, Jin; Yang, Longqiang; Jiang, Zongting; Feng, Lian; Yu, Mei; Tian, Weidong

    2015-05-01

    To compare the odontogenic potential of human dental follicle cells (DFCs) and periodontal ligament cells (PDLCs). In vitro and in vivo characterization studies of DFCs and PDLCs were performed comparatively. DFCs and PDLCs were subcutaneously implanted into the dorsum of mice for 8 weeks after combined with treated dentin matrix scaffolds respectively. Proteomic analysis identified 32 differentially expressed proteins in DFCs and PDLCs. Examination of the harvested grafts showed PDLCs could form the dentin-like tissues as DFCs did. However, the structure of dentin tissues generated by DFCs was more complete. PDLCs could contribute to regenerate dentin-like tissues in the inductive microenvironment of treated dentin matrix. DFCs presented more remarkable dentinogenic capability than PDLCs did.

  5. [Expression of human β-defensin and its relationship with inflammatory factor in human dental pulp tissue].

    Science.gov (United States)

    Yue, Zhai; Huang, Jian-Ying; Hyun, Park; Ji, Fang; Fei, Zhao-Liang; Tao, Jiang

    2017-08-01

    To investigate the expression of human β-defensin(HBD) in human dental pulp tissue and to explore the regulation of HBD in pulp inflammation and the relationship among HBD family members. The gene expression of HBD in human dental pulp tissue was assessed in NCBI GEO profiles and was verified by RT-PCR. Human dental pulp cells were stimulated with TNF-α, IL-1α, IL-1β and IL-6 in different combinations and the expression of HBD2 was analyzed by qPCR. Human dental pulp cells were pretreated with HBD110 and then stimulated with LPS and the expression of TNF-α,IL-1α and HBD2 were analyzed by qPCR. GraphPad Prism 5.01 was used to analyze the results of the experimental and the control groups. 27 HBDs were found to express in human dental pulp tissue in NCBI GEO Profiles. The joint overexpression of TNF-α, IL-1α, IL-1β and IL-6 increased the expression of HBD2; HBD110 increased the expression of HBD2 by increasing the expression of TNF-α and IL-1α. Many other HBDs have positive expression in human dental pulp issue besides of HBD1, HBD2, HBD3, HBD4 and the inflammation factors and other HBDs can regulate the expression of HBD2 in dental pulp.

  6. Cryopreservation of human dental follicle tissue for use as a resource of autologous mesenchymal stem cells.

    Science.gov (United States)

    Park, Bong-Wook; Jang, Si-Jung; Byun, June-Ho; Kang, Young-Hoon; Choi, Mun-Jeong; Park, Won-Uk; Lee, Won-Jae; Rho, Gyu-Jin

    2017-02-01

    The main purpose of this study was to develop a cryopreservation method for human dental follicle tissue to maintain autologous stem cells as a resource. A modified cryoprotectant, consisting of 0.05 m glucose, 0.05 m sucrose and 1.5 m ethylene glycol in phosphate-buffered saline (PBS) was employed, with a slow-ramp freezing rate. We observed > 70% of cell survival rate after 3 months of tissue storage. Isolated and cultured human dental stem cells (hDSCs) from cryopreserved dental follicles expressed mesenchymal stem cell markers at a level similar to that of hDSCs from fresh tissue. They also successfully differentiated in vitro into the mesenchymal lineage, osteocytes, adipocytes and chondrocytes under specific inductions. Using immunohistochemistry, the early transcription factors OCT4, NANOG and SOX2 were moderately or weakly detected in the nucleus of both fresh and cryopreserved dental follicles. In addition, p63, CCND1, BCL2 and BAX protein expression levels were the same in both fresh and cryopreserved tissues. However, the positive-cell ratio and intensity of p53 protein was higher in cryopreserved tissues than in fresh tissues, indicating direct damage of the freeze-thawing process. Real-time PCR analysis of hDSCs at passage 2 from both fresh and cryopreserved dental follicles showed similar levels of mRNA for apoptosis- and transcription-related genes. Based on these results, a newly developed cryoprotectant, along with a slow ramp rate freezing procedure allows for long-term dental tissue preservation for later use as an autologous stem cell resource in regenerative cell therapy. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

  7. Structure-mechanical function relations at nano-scale in heat-affected human dental tissue.

    Science.gov (United States)

    Sui, Tan; Sandholzer, Michael A; Le Bourhis, Eric; Baimpas, Nikolaos; Landini, Gabriel; Korsunsky, Alexander M

    2014-04-01

    The knowledge of the mechanical properties of dental materials related to their hierarchical structure is essential for understanding and predicting the effect of microstructural alterations on the performance of dental tissues in the context of forensic and archaeological investigation as well as laser irradiation treatment of caries. So far, few studies have focused on the nano-scale structure-mechanical function relations of human teeth altered by chemical or thermal treatment. The response of dental tissues to thermal treatment is thought to be strongly affected by the mineral crystallite size, their spatial arrangement and preferred orientation. In this study, synchrotron-based small and wide angle X-ray scattering (SAXS/WAXS) techniques were used to investigate the micro-structural alterations (mean crystalline thickness, crystal perfection and degree of alignment) of heat-affected dentine and enamel in human dental teeth. Additionally, nanoindentation mapping was applied to detect the spatial and temperature-dependent nano-mechanical properties variation. The SAXS/WAXS results revealed that the mean crystalline thickness distribution in dentine was more uniform compared with that in enamel. Although in general the mean crystalline thickness increased both in dentine and enamel as the temperature increased, the local structural variations gradually reduced. Meanwhile, the hardness and reduced modulus in enamel decreased as the temperature increased, while for dentine, the tendency reversed at high temperature. The analysis of the correlation between the ultrastructure and mechanical properties coupled with the effect of temperature demonstrates the effect of mean thickness and orientation on the local variation of mechanical property. This structural-mechanical property alteration is likely to be due to changes of HAp crystallites, thus dentine and enamel exhibit different responses at different temperatures. Our results enable an improved understanding of

  8. Expression of toll like receptor 4 in normal human odontoblasts and dental pulp tissue.

    Science.gov (United States)

    Jiang, Hong-Wei; Zhang, Wei; Ren, Bang-Peng; Zeng, Jin-Feng; Ling, Jun-Qi

    2006-08-01

    The aim of the study was to determine the expression of TLR4 in odontoblasts and the dental pulp. Odontoblasts and pulp tissues were collected from freshly extracted human wisdom teeth. Reverse transcription-polymerase chain reaction and Western blotting were performed to detect TLR4 mRNA and protein expression, respectively. Immunohistochemical staining was used to determine the distribution of TLR4 in odontoblasts and the pulp. Scanning electron microscopy (SEM) was applied to observe the morphology of odontoblasts. It was demonstrated that TLR4 mRNA and protein expressions were both present in cells of odontoblast layer and pulp tissues and that TLR4 expression was distributed in odontoblasts and some pulpal vascular endothelial cells. SEM revealed the integrity of the odontoblast cell-layer and the well-preserved morphology of individual odontoblast cells. These findings suggest that TLR4 expressed in odontoblasts may play an important role in the dental immune defense.

  9. DENTAL PULP TISSUE ENGINEERING

    Science.gov (United States)

    Demarco, FF; Conde, MCM; Cavalcanti, B; Casagrande, L; Sakai, V; Nör, JE

    2013-01-01

    Dental pulp is a highly specialized mesenchymal tissue, which have a restrict regeneration capacity due to anatomical arrangement and post-mitotic nature of odontoblastic cells. Entire pulp amputation followed by pulp-space disinfection and filling with an artificial material cause loss of a significant amount of dentin leaving as life-lasting sequelae a non-vital and weakened tooth. However, regenerative endodontics is an emerging field of modern tissue engineering that demonstrated promising results using stem cells associated with scaffolds and responsive molecules. Thereby, this article will review the most recent endeavors to regenerate pulp tissue based on tissue engineering principles and providing insightful information to readers about the different aspects enrolled in tissue engineering. Here, we speculate that the search for the ideal combination of cells, scaffolds, and morphogenic factors for dental pulp tissue engineering may be extended over future years and result in significant advances in other areas of dental and craniofacial research. The finds collected in our review showed that we are now at a stage in which engineering a complex tissue, such as the dental pulp, is no longer an unachievable and the next decade will certainly be an exciting time for dental and craniofacial research. PMID:21519641

  10. X-ray scattering evaluation of ultrastructural changes in human dental tissues with thermal treatment.

    Science.gov (United States)

    Sandholzer, Michael A; Sui, Tan; Korsunsky, Alexander M; Walmsley, Anthony Damien; Lumley, Philip J; Landini, Gabriel

    2014-05-01

    Micro- and ultrastructural analysis of burned skeletal remains is crucial for obtaining a reliable estimation of cremation temperature. Earlier studies mainly focused on heat-induced changes in bone tissue, while this study extends this research to human dental tissues using a novel quantitative analytical approach. Twelve tooth sections were burned at 400-900°C (30-min exposure, increments of 100°C). Subsequent combined small- and wide-angle X-ray scattering (SAXS/WAXS) experiments were performed at the Diamond Light Source synchrotron facility, where 28 scattering patterns were collected within each tooth section. In comparison with the control sample, an increase in mean crystal thickness was found in burned dentine (2.8-fold) and enamel (1.4-fold), however at a smaller rate than reported earlier for bone tissue (5-10.7-fold). The results provide a structural reference for traditional X-ray scattering methods and emphasize the need to investigate bone and dental tissues separately to obtain a reliable estimation of cremation temperature. © 2014 American Academy of Forensic Sciences.

  11. The use of human dental pulp stem cells for in vivo bone tissue engineering: A systematic review.

    Science.gov (United States)

    Leyendecker Junior, Alessander; Gomes Pinheiro, Carla Cristina; Lazzaretti Fernandes, Tiago; Franco Bueno, Daniela

    2018-01-01

    Dental pulp represents a promising and easily accessible source of mesenchymal stem cells for clinical applications. Many studies have investigated the use of human dental pulp stem cells and stem cells isolated from the dental pulp of human exfoliated deciduous teeth for bone tissue engineering in vivo. However, the type of scaffold used to support the proliferation and differentiation of dental stem cells, the animal model, the type of bone defect created, and the methods for evaluation of results were extremely heterogeneous among these studies conducted. With this issue in mind, the main objective of this study is to present and summarize, through a systematic review of the literature, in vivo studies in which the efficacy of human dental pulp stem cells and stem cells from human exfoliated deciduous teeth (SHED) for bone regeneration was evaluated. The article search was conducted in PubMed/MEDLINE and Web of Science databases. Original research articles assessing potential of human dental pulp stem cells and SHED for in vivo bone tissue engineering, published from 1984 to November 2017, were selected and evaluated in this review according to the following eligibility criteria: published in English, assessing dental stem cells of human origin and evaluating in vivo bone tissue formation in animal models or in humans. From the initial 1576 potentially relevant articles identified, 128 were excluded due to the fact that they were duplicates and 1392 were considered ineligible as they did not meet the inclusion criteria. As a result, 56 articles remained and were fully analyzed in this systematic review. The results obtained in this systematic review open new avenues to perform bone tissue engineering for patients with bone defects and emphasize the importance of using human dental pulp stem cells and SHED to repair actual bone defects in an appropriate animal model.

  12. [Expression of Na(+)/Ca(2+) exchanger channel protein in human odontoblasts and nervous tissue of dental pulp].

    Science.gov (United States)

    Zang, Chengcheng; Zhao, Zhiying; Chen, Zhen; Que, Kehua

    2015-10-01

    To investigate the expression of Na(+)/Ca(2+) exchanger 1 (NCX1) channel protein in human odontoblasts (OD) and nervous tissue of dental pulp. Twenty intact and healthy third molars extracted for orthodontic purpose were collected. The OD layer and nervous tissue were determined by dentin sialophosphoproteins (DSPP) antibody staining and modified Bielschowsky silver staining respectivelly. The immunohistochemical method was used to detect the expressions of NCX1 protein in human dental pulp tissue. The difference of expression of NCX1 in human OD at different part of dental pulp was statistically analyzed using Image Pro Plus and SPSS software. NCX1 channel protein was mainly expressed on the cell body of OD, and nervous tissue of dental pulp. The expression level of NCX1 on the OD of crown pulp was higher (A = 0.146 ± 0.021) than that on the upper part of root pulp (A = 0.120 ± 0.034), but the expression difference was not significant (P > 0.05). NCX1 channel protein was expressed on human OD and nervous tissue in dental pulp.

  13. Stem/progenitor cells from inflamed human dental pulp retain tissue regeneration potential

    Science.gov (United States)

    Alongi, Dominick J; Yamaza, Takayoshi; Song, Yingjie; Fouad, Ashraf F; Romberg, Elaine E; Shi, Songtao; Tuan, Rocky S; Huang, George T-J

    2011-01-01

    Background Potent stem/progenitor cells have been isolated from normal human dental pulps termed dental pulp stem cells (DPSCs). However, it is unknown whether these cells exist in inflamed pulps (IPs). Aims To determine whether DPSCs can be identified and isolated from IPs; and if they can be successfully cultured, whether they retain tissue regeneration potential in vivo. Materials & methods DPSCs from freshly collected normal pulps (NPs) and IPs were characterized in vitro and their tissue regeneration potential tested using an in vivo study model. Results The immunohistochemical analysis showed that IPs expressed higher levels of mesenchymal stem cell markers STRO-1, CD90, CD105 and CD146 compared with NPs (p < 0.05). Flow cytometry analysis showed that DPSCs from both NPs and IPs expressed moderate to high levels of CD146, stage-specific embryonic antigen-4, CD73 and CD166. Total population doubling of DPSCs-IPs (44.6 ± 2.9) was lower than that of DPSCs-NPs (58.9 ± 2.5) (p < 0.05), and DPSCs-IPs appeared to have a decreased osteo/dentinogenic potential compared with DPSCs-NPs based on the mineral deposition in cultures. Nonetheless, DPSCs-IPs formed pulp/dentin complexes similar to DPSCs-NPs when transplanted into immunocompromised mice. Conclusion DPSCs-IPs can be isolated and their mesenchymal stem cell marker profiles are similar to those from NPs. Although some stem cell properties of DPSCs-IPs were altered, cells from some samples remained potent in tissue regeneration in vivo. PMID:20465527

  14. Isolation and Characterization of Human Dental Pulp Stem Cells from Cryopreserved Pulp Tissues Obtained from Teeth with Irreversible Pulpitis.

    Science.gov (United States)

    Malekfar, Azin; Valli, Kusum S; Kanafi, Mohammad Mahboob; Bhonde, Ramesh R

    2016-01-01

    Human dental pulp stem cells (DPSCs) are becoming an attractive target for therapeutic purposes because of their neural crest origin and propensity. Although DPSCs can be successfully cryopreserved, there are hardly any reports on cryopreservation of dental pulp tissues obtained from teeth diagnosed with symptomatic irreversible pulpitis during endodontic treatment and isolation and characterization of DPSCs from such cryopreserved pulp. The aim of this study was to cryopreserve the said pulp tissues to propagate and characterize isolated DPSCs. A medium consisting of 90% fetal bovine serum and 10% dimethyl sulfoxide was used for cryopreservation of pulp tissues. DPSCs were isolated from fresh and cryopreserved pulp tissues using an enzymatic method. Cell viability and proliferation were determined using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. DPSC migration and interaction were analyzed with the wound healing assay. Mesenchymal characteristics of DPSCs were verified by flow cytometric analysis of cell surface CD markers. The osteogenic and adipogenic potential of DPSCs was shown by von Kossa and oil red O staining methods, respectively, and the polymerase chain reaction method. We found no significant difference in CD marker expression and osteogenic and adipogenic differentiation potential of DPSCs obtained from fresh and cryopreserved dental pulp tissue. Our study shows that dental pulp can be successfully cryopreserved without losing normal characteristics and differentiation potential of their DPSCs, thus making them suitable for dental banking and future therapeutic purposes. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  15. Microtomography evaluation of dental tissue wear surface induced by in vitro simulated chewing cycles on human and composite teeth

    Directory of Open Access Journals (Sweden)

    Rossella Bedini

    2012-01-01

    Full Text Available In this study a 3D microtomography display of tooth surfaces after in vitro dental wear tests has been obtained. Natural teeth have been compared with prosthetic teeth, manufactured by three different polyceramic composite materials. The prosthetic dental element samples, similar to molars, have been placed in opposition to human teeth extracted by paradontology diseases. After microtomography analysis, samples have been subjected to in vitro fatigue test cycles by servo-hydraulic mechanical testing machine. After the fatigue test, each sample has been subjected again to microtomography analysis to obtain volumetric value changes and dental wear surface images. Wear surface images were obtained by 3D reconstruction software and volumetric value changes were measured by CT analyser software. The aim of this work has been to show the potential of microtomography technique to display very clear and reliable wear surface images. Microtomography analysis methods to evaluate volumetric value changes have been used to quantify dental tissue and composite material wear.

  16. Human dental pulp stem cells derived from cryopreserved dental pulp tissues of vital extracted teeth with disease demonstrate hepatic-like differentiation.

    Science.gov (United States)

    Chen, Y K; Huang, Anderson H C; Chan, Anthony W S; Lin, L M

    2016-06-01

    Reviewing the literature, hepatic differentiation of human dental pulp stem cells (hDPSCs) from cryopreserved dental pulp tissues of vital extracted teeth with disease has not been studied. This study is aimed to evaluate the hypothesis that hDPSCs from cryopreserved dental pulp tissues of vital extracted teeth with disease could possess potential hepatic differentiation. Forty vital extracted teeth with disease recruited for hDPSCs isolation, stem cell characterization and hepatic differentiation were randomly and equally divided into group A (liquid nitrogen-stored dental pulp tissues) and group B (freshly derived dental pulp tissues). Samples of hDPSCs isolated from groups A and B but without hepatic growth factors formed negative controls. A well-differentiated hepatocellular carcinoma cell line was employed as a positive control. All the isolated hDPSCs from groups A and B showed hepatic-like differentiation with morphological change from a spindle-shaped to a polygonal shape and normal karyotype. Differentiated hDPSCs and the positive control expressed hepatic metabolic function genes and liver-specific genes. Glycogen storage of differentiated hDPSCs was noted from day 7 of differentiation-medium culture. Positive immunofluorescence staining of low-density lipoprotein and albumin was observed from day 14 of differentiation-medium culture; urea production in the medium was noted from week 6. No hepatic differentiation was observed for any of the samples of the negative controls. We not only demonstrated the feasibility of hepatic-like differentiation of hDPSCs from cryopreserved dental pulp tissues of vital extracted teeth with disease but also indicated that the differentiated cells possessed normal karyotype and were functionally close to normal hepatic-like cells. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  17. Stem Cells from Cryopreserved Human Dental Pulp Tissues Sequentially Differentiate into Definitive Endoderm and Hepatocyte-Like Cells in vitro

    Science.gov (United States)

    Han, Young-Jin; Kang, Young-Hoon; Shivakumar, Sarath Belame; Bharti, Dinesh; Son, Young-Bum; Choi, Yong-Ho; Park, Won-Uk; Byun, June-Ho; Rho, Gyu-Jin; Park, Bong-Wook

    2017-01-01

    We previously described a novel tissue cryopreservation protocol to enable the safe preservation of various autologous stem cell sources. The present study characterized the stem cells derived from long-term cryopreserved dental pulp tissues (hDPSCs-cryo) and analyzed their differentiation into definitive endoderm (DE) and hepatocyte-like cells (HLCs) in vitro. Human dental pulp tissues from extracted wisdom teeth were cryopreserved as per a slow freezing tissue cryopreservation protocol for at least a year. Characteristics of hDPSCs-cryo were compared to those of stem cells from fresh dental pulps (hDPSCs-fresh). hDPSCs-cryo were differentiated into DE cells in vitro with Activin A as per the Wnt3a protocol for 6 days. These cells were further differentiated into HLCs in the presence of growth factors until day 30. hDPSCs-fresh and hDPSCs-cryo displayed similar cell growth morphology, cell proliferation rates, and mesenchymal stem cell character. During differentiation into DE and HLCs in vitro, the cells flattened and became polygonal in shape, and finally adopted a hepatocyte-like shape. The differentiated DE cells at day 6 and HLCs at day 30 displayed significantly increased DE- and hepatocyte-specific markers at the mRNA and protein level, respectively. In addition, the differentiated HLCs showed detoxification and glycogen storage capacities, indicating they could share multiple functions with real hepatocytes. These data conclusively show that hPDSCs-cryo derived from long-term cryopreserved dental pulp tissues can be successfully differentiated into DE and functional hepatocytes in vitro. Thus, preservation of dental tissues could provide a valuable source of autologous stem cells for tissue engineering. PMID:29200956

  18. Stem Cells from Cryopreserved Human Dental Pulp Tissues Sequentially Differentiate into Definitive Endoderm and Hepatocyte-Like Cells in vitro.

    Science.gov (United States)

    Han, Young-Jin; Kang, Young-Hoon; Shivakumar, Sarath Belame; Bharti, Dinesh; Son, Young-Bum; Choi, Yong-Ho; Park, Won-Uk; Byun, June-Ho; Rho, Gyu-Jin; Park, Bong-Wook

    2017-01-01

    We previously described a novel tissue cryopreservation protocol to enable the safe preservation of various autologous stem cell sources. The present study characterized the stem cells derived from long-term cryopreserved dental pulp tissues (hDPSCs-cryo) and analyzed their differentiation into definitive endoderm (DE) and hepatocyte-like cells (HLCs) in vitro. Human dental pulp tissues from extracted wisdom teeth were cryopreserved as per a slow freezing tissue cryopreservation protocol for at least a year. Characteristics of hDPSCs-cryo were compared to those of stem cells from fresh dental pulps (hDPSCs-fresh). hDPSCs-cryo were differentiated into DE cells in vitro with Activin A as per the Wnt3a protocol for 6 days. These cells were further differentiated into HLCs in the presence of growth factors until day 30. hDPSCs-fresh and hDPSCs-cryo displayed similar cell growth morphology, cell proliferation rates, and mesenchymal stem cell character. During differentiation into DE and HLCs in vitro, the cells flattened and became polygonal in shape, and finally adopted a hepatocyte-like shape. The differentiated DE cells at day 6 and HLCs at day 30 displayed significantly increased DE- and hepatocyte-specific markers at the mRNA and protein level, respectively. In addition, the differentiated HLCs showed detoxification and glycogen storage capacities, indicating they could share multiple functions with real hepatocytes. These data conclusively show that hPDSCs-cryo derived from long-term cryopreserved dental pulp tissues can be successfully differentiated into DE and functional hepatocytes in vitro. Thus, preservation of dental tissues could provide a valuable source of autologous stem cells for tissue engineering.

  19. X-ray Study of Human Dental Tissues Affected by Erythroblastosis Fetalis.

    Science.gov (United States)

    Sui, T; Ying, S; Korsunsky, A M; Landini, G

    2015-07-01

    Numerous diseases are known to cause microstructural alteration of dental tissues structure. One type in particular is associated with neonatal jaundice and circulation of bilirubin in blood at high concentration due to increased hemolysis in conditions such as erythroblastosis fetalis, septicemia, biliary atresia, and other causes of hyperbilirubinemia. In those conditions, the products of the catabolism of hemoglobin end up deposited in various tissues, including teeth, where they can present clinically as visibly stained brown/green teeth. There is almost no information on the nature or extent of the structural changes taking place in these conditions. Here, advanced nondestructive wide-angle synchrotron X-ray scattering techniques combined with scanning microscopy methods were used to investigate for the first time the ultrastructure of the dental hard tissues in an archival case of intrinsically pigmented green teeth. Despite no obvious elemental variation across the pigmented tissue region, the high-resolution crystallographic properties probed by wide-angle synchrotron X-ray scattering revealed an ultrastructural variation (orientation, particle size, and lattice parameter of hydroxyapatite crystallites) associated with a pigmentation line in dentine and with a distinct neonatal line in enamel. © International & American Associations for Dental Research 2015.

  20. Efficacy of Sex Determination from Human Dental Pulp Tissue and its Reliability as a Tool in Forensic Dentistry

    Science.gov (United States)

    Khanna, Kaveri Surya

    2015-01-01

    Background: Sex determination is one of the primary steps in forensics. Barr body can be used as a histological method for identification of sex as it is found to be specific to female somatic cells and rare in male cells. To demarcate human dental pulp as an important identification tool of sex in forensic odontology (FO) and to evaluate the time period till which sex can be determined from pulp tissue using three stains H and E, Feulgen, and acridine - orange under fluorescence so as. Materials and Methods: 90 pulp samples (45 males and 45 females) were subjected to Barr body analysis for determination of sex using light and fluorescent microscopy. Results: Barr body was found to be positive for female samples and negative or rare in the male sample (<3%). Conclusion: Barr body from human dental pulp tissue can be used as a successful determinant of sex identification in FO. PMID:26668474

  1. Tissue non-specific alkaline phosphatase production by human dental pulp stromal cells is enhanced by high density cell culture.

    Science.gov (United States)

    Tomlinson, Matthew J; Dennis, Caitriona; Yang, Xuebin B; Kirkham, Jennifer

    2015-08-01

    The cell surface hydrolase tissue non-specific alkaline phosphatase (TNAP) (also known as MSCA-1) is used to identify a sub-population of bone marrow stromal cells (BMSCs) with high mineralising potential and is found on subsets of cells within the dental pulp. We aim to determine whether TNAP is co-expressed by human dental pulp stromal cells (hDPSCs) alongside a range of BMSC markers, whether this is an active form of the enzyme and the effects of culture duration and cell density on its expression. Cells from primary dental pulp and culture expanded hDPSCs expressed TNAP. Subsequent analyses revealed persistent TNAP expression and co-expression with BMSC markers such as CD73 and CD90. Flow cytometry and biochemical assays showed that increased culture durations and cell densities enhanced TNAP expression by hDPSCs. Arresting the hDPSC cell cycle also increased TNAP expression. These data confirm that TNAP is co-expressed by hDPSCs together with other BMSC markers and show that cell density affects TNAP expression levels. We conclude that TNAP is a potentially useful marker for hDPSC selection especially for uses in mineralised tissue regenerative therapies.

  2. The irradiation action on human dental tissue by X-rays and electrons--a nanoindenter study.

    Science.gov (United States)

    Fränzel, Wolfgang; Gerlach, Reinhard

    2009-01-01

    It is known that ionizing radiation is used in medicine for Roentgen diagnostics and for radiation therapy. The radiation interacts with matter, in particular with biological one, essentially by scattering, photoelectric effect, Compton effect and pair production. To what extent the biological material is changed thereby, depends on the type and the amount of radiation energy, on the dose and on the tissue constitution. In modern radiation therapy two different kinds of radiation are used: high energy X-rays and electron radiation. In the case of head-neck tumors the general practice is an irradiation with high energy X-rays with absorbed dose to water up to 70 Gy. Teeth destruction has been identified as a side effect during irradiation. In addition, damage to the salivary glands is often observed which leads to a decrease or even the complete loss of the salivary secretion (xerostomia). This study shows how the different energy and radiation types damage the tooth tissue. The effects of both, high X-ray energy and high energy electrons, on the mechanical properties hardness and elasticity of the human dental tissue are measured by the nanoindentation technique. We compare these results with the effect of the irradiation of low X-ray energy on the dental tissue.

  3. Efficacy of Sex Determination from Human Dental Pulp Tissue and its Reliability as a Tool in Forensic Dentistry

    OpenAIRE

    Khanna, Kaveri Surya

    2015-01-01

    Background: Sex determination is one of the primary steps in forensics. Barr body can be used as a histological method for identification of sex as it is found to be specific to female somatic cells and rare in male cells. To demarcate human dental pulp as an important identification tool of sex in forensic odontology (FO) and to evaluate the time period till which sex can be determined from pulp tissue using three stains H and E, Feulgen, and acridine - orange under fluorescence so as. Mater...

  4. Engineering three dimensional micro nerve tissue using postnatal stem cells from human dental apical papilla.

    Science.gov (United States)

    Kim, Byung-Chul; Jun, Sung-Min; Kim, So Yeon; Kwon, Yong-Dae; Choe, Sung Chul; Kim, Eun-Chul; Lee, Jae-Hyung; Kim, Jinseok; Suh, Jun-Kyo Francis; Hwang, Yu-Shik

    2017-04-01

    The in vitro generation of cell-based three dimensional (3D) nerve tissue is an attractive subject to improve graft survival and integration into host tissue for neural tissue regeneration or to model biological events in stem cell differentiation. Although 3D organotypic culture strategies are well established for 3D nerve tissue formation of pluripotent stem cells to study underlying biology in nerve development, cell-based nerve tissues have not been developed using human postnatal stem cells with therapeutic potential. Here, we established a culture strategy for the generation of in vitro cell-based 3D nerve tissue from postnatal stem cells from apical papilla (SCAPs) of teeth, which originate from neural crest-derived ectomesenchyme cells. A stem cell population capable of differentiating into neural cell lineages was generated during the ex vivo expansion of SCAPs in the presence of EGF and bFGF, and SCAPs differentiated into neural cells, showing neural cell lineage-related molecular and gene expression profiles, morphological changes and electrophysical property under neural-inductive culture conditions. Moreover, we showed the first evidence that 3D cell-based nerve-like tissue with axons and myelin structures could be generated from SCAPs via 3D organotypic culture using an integrated bioprocess composed of polyethylene glycol (PEG) microwell-mediated cell spheroid formation and subsequent dynamic culture in a high aspect ratio vessel (HARV) bioreactor. In conclusion, the culture strategy in our study provides a novel approach to develop in vitro engineered nerve tissue using SCAPs and a foundation to study biological events in the neural differentiation of postnatal stem cells. Biotechnol. Bioeng. 2017;114: 903-914. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  5. Tooth Tissue Engineering: The Importance of Blood Products as a Supplement in Tissue Culture Medium for Human Pulp Dental Stem Cells.

    Science.gov (United States)

    Pisciolaro, Ricardo Luiz; Duailibi, Monica Talarico; Novo, Neil Ferreira; Juliano, Yara; Pallos, Debora; Yelick, Pamela Crotty; Vacanti, Joseph Phillip; Ferreira, Lydia Masako; Duailibi, Silvio Eduardo

    2015-11-01

    One of the goals in using cells for tissue engineering (TE) and cell therapy consists of optimizing the medium for cell culture. The present study compares three different blood product supplements for improved cell proliferation and protection against DNA damage in cultured human dental pulp stem cells for tooth TE applications. Human cells from dental pulp were first characterized as adult stem cells (ectomesenchymal mixed origin) by flow cytometry. Next, four different cell culture conditions were tested: I, supplement-free; II, supplemented with fetal bovine serum; III, allogeneic human serum; and IV, autologous human serum. Cultured cells were then characterized for cell proliferation, mineralized nodule formation, and colony-forming units (CFU) capability. After 28 days in culture, the comet assay was performed to assess possible damage in cellular DNA. Our results revealed that Protocol IV achieved higher cell proliferation than Protocol I (p = 0.0112). Protocols II and III resulted in higher cell proliferation than Protocol I, but no statistical differences were found relative to Protocol IV. The comet assay revealed less cell damage in cells cultured using Protocol IV as compared to Protocols II and III. The damage percentage observed on Protocol II was significantly higher than all other protocols. CFUs capability was highest using Protocol IV (p = 0.0018) and III, respectively, and the highest degree of mineralization was observed using Protocol IV as compared to Protocols II and III. Protocol IV resulted in significantly improved cell proliferation, and no cell damage was observed. These results demonstrate that human blood product supplements can be used as feasible supplements for culturing adult human dental stem cells.

  6. Human Dental Pulp-Derived Cells Produce Bone-Like Tissue and Exhibit Bone Cell-Like Responsiveness to Mechanical Loading

    DEFF Research Database (Denmark)

    Kraft, David Christian Evar; Melsen, Birte; Bindslev, Dorthe Arenholt

    2010-01-01

    Recent studies have shown that dental pulp cells possess stem cell like potential and thus may be potential candidates for tissue engineering purposes particularly in the oro-facial region. Successful tissue engineering ideally requires that newly formed bone adapts its mass, shape, and trabecular...... architecture to the prevailing mechanical load and should be able to conduct bone cell-specific functions, such as bone remodeling. In vitro investigation of the responsiveness of different cell types to mechanical loading is so far a relative new research field. The aim of this study was to establish...... and characterize cell lines from human 3rd molar dental pulp tissue to determine whether human dental pulp-derived cells (DPCs) are osteogenic and responsive to mechanical loading by pulsating fluid flow (PFF) in vitro. Methods: Human DPCs used for this study were characterized by measuring proliferation...

  7. In vivo differentiation of human periodontal ligament cells leads to formation of dental hard tissue.

    Science.gov (United States)

    Wolf, M; Lossdörfer, S; Abuduwali, N; Meyer, R; Kebir, S; Götz, W; Jäger, A

    2013-11-01

    Following trauma, periodontal disease, or orthodontic tooth movement, residual periodontal ligament (PDL) cells at the defect site are considered mandatory for successful regeneration of the injured structures. Recent developments in tissue engineering focus, as one pillar, on the transplantation of PDL cells to support periodontal regeneration processes. Here, we examined the ability of osteogenically predifferentiated PDL cells to undergo further osteoblastic or cementoblastic differentiation and to mineralize their extracellular matrix when transplanted in an in vivo microenvironment. Using collagen sponges as carriers, osteogenically predifferentiated human PDL cells were transplanted subcutaneously into six immunocompromised CD-1® nude mice. Following explantation after 28 days, osteogenic and cementogenic marker protein expression was visualized immunohistochemically. After 28 days, transplanted PDL cells revealed both cellular, cytoplasmatic and extracellular immunoreactivity for the chosen markers alkaline phosphatase, osteopontin, PTH-receptor 1, and osteocalcin. Specific osteogenic and cementoblastic differentiation was demonstrated by RUNX2 and CEMP1 immunoreactivity. Early stages of mineralization were demonstrated by calcium and phosphate staining. Our results reinforce the previously published reports of PDL cell mineralization in vivo and further demonstrate the successful induction of specific osteogenic and cementogenic differentiation of transplanted human PDL cells in vivo. These findings reveal promising possibilities for supporting periodontal remodeling and regeneration processes with PDL cells being potential target cells with which to influence the process of orthodontically induced root resorption.

  8. Engineered neural tissue with Schwann cell differentiated human dental pulp stem cells: potential for peripheral nerve repair?

    Science.gov (United States)

    Sanen, Kathleen; Martens, Wendy; Georgiou, Melanie; Ameloot, Marcel; Lambrichts, Ivo; Phillips, James

    2017-01-04

    Despite the spontaneous regenerative capacity of the peripheral nervous system, large gap peripheral nerve injuries (PNIs) require bridging strategies. The limitations and suboptimal results obtained with autografts or hollow nerve conduits in the clinic urge the need for alternative treatments. Recently, we have described promising neuroregenerative capacities of Schwann cells derived from differentiated human dental pulp stem cells (d-hDPSCs) in vitro. Here, we extended the in vitro assays to show the pro-angiogenic effects of d-hDPSCs, such as enhanced endothelial cell proliferation, migration and differentiation. In addition, for the first time we evaluated the performance of d-hDPSCs in an in vivo rat model of PNI. Eight weeks after transplantation of NeuraWrap™ conduits filled with engineered neural tissue (EngNT) containing aligned d-hDPSCs in 15-mm rat sciatic nerve defects, immunohistochemistry and ultrastructural analysis revealed ingrowing neurites, myelinated nerve fibres and blood vessels along the construct. Although further research is required to optimize the delivery of this EngNT, our findings suggest that d-hDPSCs are able to exert a positive effect in the regeneration of nerve tissue in vivo. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Regenerative medicine in dental and oral tissues: Dental pulp mesenchymal stem cell

    Directory of Open Access Journals (Sweden)

    Janti Sudiono

    2017-08-01

    Full Text Available Background. Regenerative medicine is a new therapeutic modality using cell, stem cell and tissue engineering technologies. Purpose. To describe the regenerative capacity of dental pulp mesenchymal stem cell. Review. In dentistry, stem cell and tissue engineering technologies develop incredibly and attract great interest, due to the capacity to facilitate innovation in dental material and regeneration of dental and oral tissues. Mesenchymal stem cells derived from dental pulp, periodontal ligament and dental follicle, can be isolated, cultured and differentiated into various cells, so that can be useful for regeneration of dental, nerves, periodontal and bone tissues. Tissue engineering is a technology in reconstructive biology, which utilizes mechanical, cellular, or biological mediators to facilitate regeneration or reconstruction of a particular tissue. The multipotency, high proliferation rates and accessibility, make dental pulp as an attractive source of mesenchymal stem cells for tissue regeneration. Revitalized dental pulp and continued root development is the focus of regenerative endodontic while biological techniques that can restore lost alveolar bone, periodontal ligament, and root cementum is the focus of regenerative periodontic. Conclucion. Dentin-derived morphogens such as BMP are known to be involved in the regulation of odontogenesis. The multipotency and angiogenic capacity of DPSCs as the regenerative capacity of human dentin / pulp complex indicated that dental pulp may contain progenitors that are responsible for dentin repair. The human periodontal ligament is a viable alternative source for possible primitive precursors to be used in stem cell therapy.

  10. Air atmospheric-pressure plasma-jet treatment enhances the attachment of human gingival fibroblasts for early peri-implant soft tissue seals on titanium dental implant abutments.

    Science.gov (United States)

    Lee, Jung-Hwan; Kim, Yong-Hee; Choi, Eun-Ha; Kim, Kwang-Mahn; Kim, Kyoung-Nam

    2015-01-01

    Although dental implants are commonly used for tooth restoration, there is a lack of studies of treatment regimens for preventing extra-oral infection and decreasing osseointegration failures by establishing early peri-implant soft tissue seals on titanium dental implant abutments. In this study, air atmospheric-pressure plasma-jet (AAPPJ) treatment was applied to titanium disks to assay the potential for early peri-implant soft tissue seals on titanium dental implant abutment. After titanium disks were treated with AAPPJ for 10 s at 250, 500, 1000 and 1500 sccm, surface analysis was performed; the control group received air only or no treatment. Human gingival fibroblasts (HGF) were seeded onto the specimens for evaluating cell attachment and proliferation and adherent-cell morphology was visualized via confocal microscopy. In AAPPJ-treated specimens, the water contact angle decreased according to increased flow rate. Oxygen composition increased in XPS, but no topographical changes were detected. The effect of AAPPJ treatment at 1000 sccm was apparent 2 mm from the treated spot, with a 20% increase in early cell attachment and proliferation. Adherent HGF on AAPPJ-treated specimens displayed a stretched phenotype with more vinculin formation than the control group. Within the limitations of this study, the results indicate that AAPPJ treatment may enhance the early attachment and proliferation of HGF for establishing early peri-implant soft tissue seals on titanium dental implant abutments with possible favorable effects of osseointegration of dental implant.

  11. Laser Ablatin of Dental Hard Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Seka, W.; Rechmann, P.; Featherstone, J.D.B.; Fried, D.

    2007-07-31

    This paper discusses ablation of dental hard tissue using pulsed lasers. It focuses particularly on the relevant tissue and laser parameters and some of the basic ablation processes that are likely to occur. The importance of interstitial water and its phase transitions is discussed in some detail along with the ablation processes that may or may not directly involve water. The interplay between tissue parameters and laser parameters in the outcome of the removal of dental hard tissue is discussed in detail.

  12. Tissue Engineering in Regenerative Dental Therapy

    Directory of Open Access Journals (Sweden)

    Hiral Jhaveri-Desai

    2011-01-01

    Full Text Available Tissue engineering is amongst the latest exciting technologies having impacted the field of dentistry. Initially considered as a futuristic approach, tissue engineering is now being successfully applied in regenerative surgery. This article reviews the important determinants of tissue engineering and how they contribute to the improvement of wound healing and surgical outcomes in the oral region. Furthermore, we shall address the clinical applications of engineering involving oral and maxillofacial surgical and periodontal procedures along with other concepts that are still in experimental phase of development. This knowledge will aid the surgical and engineering researchers to comprehend the collaboration between these fields leading to extounding dental applications and to ever-continuing man-made miracles in the field of human science.

  13. Dental tissue regeneration - a mini-review.

    Science.gov (United States)

    Yen, A-H; Yelick, P C

    2011-01-01

    with today's 21st century technological advancements, it is expected that individuals will either retain their natural teeth or obtain functional tooth replacements throughout their entire life. Modern dental therapies for the replacement of missing teeth largely utilize partial or complete dentures and titanium implants capped with prosthetic crowns. Although these prostheses serve a purpose, they are not equivalent, neither in function nor aesthetics, to natural teeth. Recent progress in dental tissue engineering has lent significant credibility to the concept that biological replacement teeth therapies may soon be available to replace missing teeth. in this review, we summarize the emerging concepts of whole-tooth replacement strategies, using postnatal dental stem cells (DSCs) and dental tissue engineering approaches. we provide a thorough and extensive review of the literature. current approaches to achieve clinically relevant biological replacement tooth therapies rely on the cultivation of DSCs capable of relaying odontogenic induction signals, through dental epithelial-mesenchymal cell interactions. DSC expansion and differentiation can be achieved by programming progenitor stem cells to adopt dental lineages, using instructive, bioengineered scaffold materials. Periodontal ligament regeneration in particular has demonstrated significant progress recently, despite the somewhat unpredictable clinical outcomes, with regard to its capacity to augment conventional metallic dental implants and as an important component for whole-tooth tissue engineering. Following recent advances made in DSC and tissue engineering research, various research groups are in the midst of performing 'proof of principle' experiments for whole-tooth regeneration, with associated functional periodontal tissues. This mini-review focuses on recent and promising developments in the fields of pulp and periodontal tissue DSCs that are of particular relevance for dental tissue and whole

  14. Tissue response: biomaterials, dental implants, and compromised osseous tissue.

    Science.gov (United States)

    Babu RS, Arvind; Ogle, Orrett

    2015-04-01

    Tissue response represents an important feature in biocompatibility in implant procedures. This review article highlights the fundamental characteristics of tissue response after the implant procedure. This article also highlights the tissue response in compromised osseous conditions. Understanding the histologic events after dental implants in normal and abnormal bone reinforces the concept of case selection in dental implants. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Investigation of the structure of human dental tissue at multiple length scales using high energy synchrotron X-ray SAXS/WAXS

    Science.gov (United States)

    Sui, Tan; Landini, Gabriel; Korsunsky, Alexander M.

    2011-10-01

    High energy (>50keV) synchrotron X-ray scattering experiments were carried out on beamline I12 JEEP at the Diamond Light Source (DLS, Oxford, UK). Although a complete human tooth could be studied, in the present study attention was focused on coupons from the region of the Dentin-Enamel Junction (DEJ). Simultaneous high energy SAXS/WAXS measurements were carried out. Quantitative analysis of the results allows multiple length scale characterization of the nano-crystalline structure of dental tissues. SAXS patterns analysis provide insight into the mean thickness and orientation of hydroxyapatite particles, while WAXS (XRD) patterns allow the determination of the crystallographic unit cell parameters of the hydroxyapatite phase. It was found that the average particle thickness determined from SAXS interpretation varies as a function of position in the vicinity of the DEJ. Most mineral particles are randomly orientated within dentin, although preferred orientation emerges and becomes stronger on approach to the enamel. Within the enamel, texture is stronger than anywhere in the dentin, and the determination of lattice parameters can be accomplished by Pawley refinement of the multiple peak diffraction pattern. The results demonstrate the feasibility of using high energy synchrotron X-ray beams for the characterization of human dental tissues. This opens up the opportunity of studying thick samples (e.g., complete teeth) in complex sample environments (e.g., under saline solution). This opens new avenues for the application of high energy synchrotron X-ray scattering to dental research.

  16. Mycoplasma detection and elimination are necessary for the application of stem cell from human dental apical papilla to tissue engineering and regenerative medicine.

    Science.gov (United States)

    Kim, Byung-Chul; Kim, So Yeon; Kwon, Yong-Dae; Choe, Sung Chul; Han, Dong-Wook; Hwang, Yu-Shik

    2015-01-01

    Recently, postnatal stem cells from dental papilla with neural crest origin have been considered as one of potent stem cell sources in regenerative medicine regarding their multi-differentiation capacity and relatively easy access. However, almost human oral tissues have been reported to be infected by mycoplasma which gives rise to oral cavity in teeth, and mycoplasma contamination of ex-vivo cultured stem cells from such dental tissues and its effect on stem cell culture has received little attention. In this study, mycoplama contamination was evaluated with stem cells from apical papilla which were isolated from human third molar and premolars from various aged patients undergoing orthodontic therapy. The ex-vivo expanded stem cells from apical papilla were found to express stem cell markers such as Stro-1, CD44, nestin and CD133, but mycoplama contamination was detected in almost all cell cultures of the tested 20 samples, which was confirmed by mycoplasma-specific gene expression and fluorescence staining. Such contaminated mycoplasma could be successfully eliminated using elimination kit, and proliferation test showed decreased proliferation activity in mycoplasma-contaminated cells. After elimination of contaminated mycoplasma, stem cells from apical papilla showed osteogenic and neural lineage differentiation under certain culture conditions. Our study proposes that the evaluation of mycoplasma contamination and elimination process might be required in the use of stem cells from apical papilla for their potent applications to tissue engineering and regenerative medicine.

  17. Correlation between Fibrillin-1 Degradation and mRNA Downregulation and Myofibroblast Differentiation in Cultured Human Dental Pulp Tissue

    Science.gov (United States)

    Yoshiba, Nagako; Yoshiba, Kunihiko; Ohkura, Naoto; Takei, Erika; Edanami, Naoki; Oda, Youhei; Hosoya, Akihiro; Nakamura, Hiroaki; Okiji, Takashi

    2015-01-01

    Myofibroblasts and extracellular matrix are important components in wound healing. Alpha-smooth muscle actin (α-SMA) is a marker of myofibroblasts. Fibrillin-1 is a major constituent of microfibrils and an extracellular-regulator of TGF-β1, an important cytokine in the transdifferentiation of resident fibroblasts into myofibroblasts. To study the correlation between changes in fibrillin-1 expression and myofibroblast differentiation, we examined alterations in fibrillin-1 and α-SMA expression in organotypic cultures of dental pulp in vitro. Extracted healthy human teeth were cut to 1-mm-thick slices and cultured for 7 days. In intact dental pulp, fibrillin-1 was broadly distributed, and α-SMA was observed in pericytes and vascular smooth muscle cells. After 7 days of culture, immunostaining for fibrillin-1 became faint concomitant with a downregulation in its mRNA levels. Furthermore, fibroblasts, odontoblasts and Schwann cells were immunoreactive for α-SMA with a significant increase in α-SMA mRNA expression. Double immunofluorescence staining was positive for pSmad2/3, central mediators of TGF-β signaling, and α-SMA. The administration of inhibitors for extracellular matrix proteases recovered fibrillin-1 immunostaining; moreover, fibroblasts lost their immunoreactivity for α-SMA along with a downregulation in α-SMA mRNA. These findings suggest that the expression of α-SMA is TGF-β1 dependent, and fibrillin-1 degradation and downregulation might be implicated in the differentiation of myofibroblasts in dental pulp wound healing. PMID:25805839

  18. Wnt and BMP Signaling Crosstalk in Regulating Dental Stem Cells: Implications in Dental Tissue Engineering.

    Science.gov (United States)

    Zhang, Fugui; Song, Jinglin; Zhang, Hongmei; Huang, Enyi; Song, Dongzhe; Tollemar, Viktor; Wang, Jing; Wang, Jinhua; Mohammed, Maryam; Wei, Qiang; Fan, Jiaming; Liao, Junyi; Zou, Yulong; Liu, Feng; Hu, Xue; Qu, Xiangyang; Chen, Liqun; Yu, Xinyi; Luu, Hue H; Lee, Michael J; He, Tong-Chuan; Ji, Ping

    2016-12-01

    Tooth is a complex hard tissue organ and consists of multiple cell types that are regulated by important signaling pathways such as Wnt and BMP signaling. Serious injuries and/or loss of tooth or periodontal tissues may significantly impact aesthetic appearance, essential oral functions and the quality of life. Regenerative dentistry holds great promise in treating oral/dental disorders. The past decade has witnessed a rapid expansion of our understanding of the biological features of dental stem cells, along with the signaling mechanisms governing stem cell self-renewal and differentiation. In this review, we first summarize the biological characteristics of seven types of dental stem cells, including dental pulp stem cells, stem cells from apical papilla, stem cells from human exfoliated deciduous teeth, dental follicle precursor cells, periodontal ligament stem cells, alveolar bone-derived mesenchymal stem cells (MSCs), and MSCs from gingiva. We then focus on how these stem cells are regulated by bone morphogenetic protein (BMP) and/or Wnt signaling by examining the interplays between these pathways. Lastly, we analyze the current status of dental tissue engineering strategies that utilize oral/dental stem cells by harnessing the interplays between BMP and Wnt pathways. We also highlight the challenges that must be addressed before the dental stem cells may reach any clinical applications. Thus, we can expect to witness significant progresses to be made in regenerative dentistry in the coming decade.

  19. Wnt and BMP signaling crosstalk in regulating dental stem cells: Implications in dental tissue engineering

    Directory of Open Access Journals (Sweden)

    Fugui Zhang

    2016-12-01

    Full Text Available Tooth is a complex hard tissue organ and consists of multiple cell types that are regulated by important signaling pathways such as Wnt and BMP signaling. Serious injuries and/or loss of tooth or periodontal tissues may significantly impact aesthetic appearance, essential oral functions and the quality of life. Regenerative dentistry holds great promise in treating oral/dental disorders. The past decade has witnessed a rapid expansion of our understanding of the biological features of dental stem cells, along with the signaling mechanisms governing stem cell self-renewal and differentiation. In this review, we first summarize the biological characteristics of seven types of dental stem cells, including dental pulp stem cells, stem cells from apical papilla, stem cells from human exfoliated deciduous teeth, dental follicle precursor cells, periodontal ligament stem cells, alveolar bone-derived mesenchymal stem cells (MSCs, and MSCs from gingiva. We then focus on how these stem cells are regulated by bone morphogenetic protein (BMP and/or Wnt signaling by examining the interplays between these pathways. Lastly, we analyze the current status of dental tissue engineering strategies that utilize oral/dental stem cells by harnessing the interplays between BMP and Wnt pathways. We also highlight the challenges that must be addressed before the dental stem cells may reach any clinical applications. Thus, we can expect to witness significant progresses to be made in regenerative dentistry in the coming decade.

  20. Nanomaterials for Craniofacial and Dental Tissue Engineering.

    Science.gov (United States)

    Li, G; Zhou, T; Lin, S; Shi, S; Lin, Y

    2017-07-01

    Tissue engineering shows great potential as a future treatment for the craniofacial and dental defects caused by trauma, tumor, and other diseases. Due to the biomimetic features and excellent physiochemical properties, nanomaterials are of vital importance in promoting cell growth and stimulating tissue regeneration in tissue engineering. For craniofacial and dental tissue engineering, the frequently used nanomaterials include nanoparticles, nanofibers, nanotubes, and nanosheets. Nanofibers are attractive for cell invasion and proliferation because of their resemblance to extracellular matrix and the presence of large pores, and they have been used as scaffolds in bone, cartilage, and tooth regeneration. Nanotubes and nanoparticles improve the mechanical and chemical properties of scaffold, increase cell attachment and migration, and facilitate tissue regeneration. In addition, nanofibers and nanoparticles are also used as a delivery system to carry the bioactive agent in bone and tooth regeneration, have better control of the release speed of agent upon degradation of the matrix, and promote tissue regeneration. Although applications of nanomaterials in tissue engineering remain in their infancy with numerous challenges to face, the current results indicate that nanomaterials have massive potential in craniofacial and dental tissue engineering.

  1. Dental Tissue — New Source for Stem Cells

    OpenAIRE

    Petrovic, Vladimir; Stefanovic, Vladisav

    2009-01-01

    Stem cells have been isolated from many tissues and organs, including dental tissue. Five types of dental stem cells have been established: dental pulp stem cells, stem cells from exfoliated deciduous teeth, stem cells from apical papilla, periodontal ligament stem cells, and dental follicle progenitor cells. The main characteristics of dental stem cells are their potential for multilineage differentiation and self-renewal capacity. Dental stem cells can differentiate into odontoblasts, adipo...

  2. Dental Stem Cells and their Applications in Dental Tissue Engineering.

    Science.gov (United States)

    Lymperi, S; Ligoudistianou, C; Taraslia, V; Kontakiotis, E; Anastasiadou, E

    2013-01-01

    Tooth loss or absence is a common condition that can be caused by various pathological circumstances. The replacement of the missing tooth is important for medical and aesthetic reasons. Recently, scientists focus on tooth tissue engineering, as a potential treatment, beyond the existing prosthetic methods. Tooth engineering is a promising new therapeutic approach that seeks to replace the missing tooth with a bioengineered one or to restore the damaged dental tissue. Its main tool is the stem cells that are seeded on the surface of biomaterials (scaffolds), in order to create a biocomplex. Several populations of mesenchymal stem cells are found in the tooth. These different cell types are categorized according to their location in the tooth and they demonstrate slightly different features. It appears that the dental stem cells isolated from the dental pulp and the periodontal ligament are the most powerful cells for tooth engineering. Additional research needs to be performed in order to address the problem of finding a suitable source of epithelial stem cells, which are important for the regeneration of the enamel. Nevertheless, the results of the existing studies are encouraging and strongly support the belief that tooth engineering can offer hope to people suffering from dental problems or tooth loss.

  3. The Neurovascular Properties of Dental Stem Cells and Their Importance in Dental Tissue Engineering

    Science.gov (United States)

    Ratajczak, Jessica; Bronckaers, Annelies; Dillen, Yörg; Gervois, Pascal; Vangansewinkel, Tim; Driesen, Ronald B.; Wolfs, Esther; Lambrichts, Ivo

    2016-01-01

    Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be distinguished, such as dental pulp stem cells, stem cells from human deciduous teeth, stem cells from the apical papilla, dental follicle stem cells, and periodontal ligament stem cells. Given their straightforward and relatively easy isolation from extracted third molars, dental stem cells (DSCs) have become an attractive source of mesenchymal-like stem cells. Over the past decade, there have been numerous studies supporting the angiogenic, neuroprotective, and neurotrophic effects of the DSC secretome. Together with their ability to differentiate into endothelial cells and neural cell types, this makes DSCs suitable candidates for dental tissue engineering and nerve injury repair. PMID:27688777

  4. The Neurovascular Properties of Dental Stem Cells and Their Importance in Dental Tissue Engineering.

    Science.gov (United States)

    Ratajczak, Jessica; Bronckaers, Annelies; Dillen, Yörg; Gervois, Pascal; Vangansewinkel, Tim; Driesen, Ronald B; Wolfs, Esther; Lambrichts, Ivo; Hilkens, Petra

    2016-01-01

    Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be distinguished, such as dental pulp stem cells, stem cells from human deciduous teeth, stem cells from the apical papilla, dental follicle stem cells, and periodontal ligament stem cells. Given their straightforward and relatively easy isolation from extracted third molars, dental stem cells (DSCs) have become an attractive source of mesenchymal-like stem cells. Over the past decade, there have been numerous studies supporting the angiogenic, neuroprotective, and neurotrophic effects of the DSC secretome. Together with their ability to differentiate into endothelial cells and neural cell types, this makes DSCs suitable candidates for dental tissue engineering and nerve injury repair.

  5. Morphological and atomic analytical changes after CO2 laser irradiation emitted at 9.3 microns on human dental hard tissues.

    Science.gov (United States)

    Takahashi, K; Kimura, Y; Matsumoto, K

    1998-06-01

    The purposes of this study were to examine the effects of CO2 laser emitted at 9.3 microns on human sound and carious dental hard tissue ablation with a stereoscope, scanning electron microscope (SEM), and energy dispersive X-ray spectrometer (SEM-EDX) and to identify possible applications of this laser in clinical treatment. There has been no report of morphological changes or atomic analytical studies on carious hard tissues after laser irradiation with 9.3 microns CO2 laser. Sixty extracted human teeth with no caries and sixty teeth with enamel or dentin caries were used for this study. All teeth were horizontally sectioned into slices (approximately 3 mm in thickness) and the samples were irradiated with CO2 laser using the following two parameters: a fluence of 78 J/cm2 and 5 pps for 2 sec. After laser irradiation, half of the samples were observed by stereoscopy and SEM and the other half were analyzed by SEM-EDX. The lased sound enamel and dentin surfaces showed crater-like structures which had been produced by the high laser energy. On the other hand, some portions of carious hard tissues were evaported by the laser. A slight amount of carbonization was observed by stereoscopy. Calcium (Ca) and phosphorus (P) content of sound or carious hard tissues was increased significantly (p laser irradiation, but the ratio of Ca to P after laser irradiation was significantly increased (p CO2 laser may be useful for the prevention or removal of caries in clinical situations.

  6. Influence of the mechanical environment on the engineering of mineralised tissues using human dental pulp stem cells and silk fibroin scaffolds.

    Directory of Open Access Journals (Sweden)

    Anna Woloszyk

    Full Text Available Teeth constitute a promising source of stem cells that can be used for tissue engineering and regenerative medicine purposes. Bone loss in the craniofacial complex due to pathological conditions and severe injuries could be treated with new materials combined with human dental pulp stem cells (hDPSCs that have the same embryonic origin as craniofacial bones. Optimising combinations of scaffolds, cells, growth factors and culture conditions still remains a great challenge. In the present study, we evaluate the mineralisation potential of hDPSCs seeded on porous silk fibroin scaffolds in a mechanically dynamic environment provided by spinner flask bioreactors. Cell-seeded scaffolds were cultured in either standard or osteogenic media in both static and dynamic conditions for 47 days. Histological analysis and micro-computed tomography of the samples showed low levels of mineralisation when samples were cultured in static conditions (0.16±0.1 BV/TV%, while their culture in a dynamic environment with osteogenic medium and weekly µCT scans (4.9±1.6 BV/TV% significantly increased the formation of homogeneously mineralised structures, which was also confirmed by the elevated calcium levels (4.5±1.0 vs. 8.8±1.7 mg/mL. Molecular analysis of the samples showed that the expression of tooth correlated genes such as Dentin Sialophosphoprotein and Nestin were downregulated by a factor of 6.7 and 7.4, respectively, in hDPSCs when cultured in presence of osteogenic medium. This finding indicates that hDPSCs are able to adopt a non-dental identity by changing the culture conditions only. Also an increased expression of Osteocalcin (1.4x and Collagen type I (1.7x was found after culture under mechanically dynamic conditions in control medium. In conclusion, the combination of hDPSCs and silk scaffolds cultured under mechanical loading in spinner flask bioreactors could offer a novel and promising approach for bone tissue engineering where appropriate and

  7. Influence of the mechanical environment on the engineering of mineralised tissues using human dental pulp stem cells and silk fibroin scaffolds.

    Science.gov (United States)

    Woloszyk, Anna; Holsten Dircksen, Sabrina; Bostanci, Nagihan; Müller, Ralph; Hofmann, Sandra; Mitsiadis, Thimios A

    2014-01-01

    Teeth constitute a promising source of stem cells that can be used for tissue engineering and regenerative medicine purposes. Bone loss in the craniofacial complex due to pathological conditions and severe injuries could be treated with new materials combined with human dental pulp stem cells (hDPSCs) that have the same embryonic origin as craniofacial bones. Optimising combinations of scaffolds, cells, growth factors and culture conditions still remains a great challenge. In the present study, we evaluate the mineralisation potential of hDPSCs seeded on porous silk fibroin scaffolds in a mechanically dynamic environment provided by spinner flask bioreactors. Cell-seeded scaffolds were cultured in either standard or osteogenic media in both static and dynamic conditions for 47 days. Histological analysis and micro-computed tomography of the samples showed low levels of mineralisation when samples were cultured in static conditions (0.16±0.1 BV/TV%), while their culture in a dynamic environment with osteogenic medium and weekly µCT scans (4.9±1.6 BV/TV%) significantly increased the formation of homogeneously mineralised structures, which was also confirmed by the elevated calcium levels (4.5±1.0 vs. 8.8±1.7 mg/mL). Molecular analysis of the samples showed that the expression of tooth correlated genes such as Dentin Sialophosphoprotein and Nestin were downregulated by a factor of 6.7 and 7.4, respectively, in hDPSCs when cultured in presence of osteogenic medium. This finding indicates that hDPSCs are able to adopt a non-dental identity by changing the culture conditions only. Also an increased expression of Osteocalcin (1.4x) and Collagen type I (1.7x) was found after culture under mechanically dynamic conditions in control medium. In conclusion, the combination of hDPSCs and silk scaffolds cultured under mechanical loading in spinner flask bioreactors could offer a novel and promising approach for bone tissue engineering where appropriate and rapid bone

  8. Combined effects of mineral trioxide aggregate and human placental extract on rat pulp tissue and growth, differentiation and angiogenesis in human dental pulp cells.

    Science.gov (United States)

    Chang, Seok-Woo; Kim, Ji-Youn; Kim, Mi-Joo; Kim, Ga-Hyun; Yi, Jin-Kyu; Lee, Deok-Won; Kum, Kee-Yeon; Kim, Eun-Cheol

    2016-01-01

    The aim of this study was to evaluate the combined effects of mineral trioxide aggregate (MTA) and human placental extract (HPE) on cell growth, differentiation and in vitro angiogenesis of human dental pulp cells (HDPCs) and to identify underlying signal transduction mechanisms. In vivo dental pulp responses in rats for a pulp-capping agent were examined. MTS assay. ALP activity test, alizarin red S staining and RT-PCR for marker genes were carried out to evaluate cell growth and differentiation. HUVEC migration, mRNA expression and capillary tube formation were measured to evaluate angiogenesis. Signal transduction was analysed using Western blotting and confocal microscopy. The pulps of rat maxillary first molars were exposed and capped with either MTA or MTA plus HPE. Histologic observation and scoring were performed. Compared to treatment of HDPCs with either HPE or MTA alone, the combination of HPE and MTA increased cell growth, ALP activity, mineralized nodules and expression of marker mRNAs. Combination HPE and MTA increased migration, capillary tube formation and angiogenic gene expression compared with MTA alone. Activation of Akt, mammalian target of rapamycin (mTOR), p38, JNK and ERK MAPK, Akt, and NF-κB were significantly increased by combining HPE and MTA compared with MTA alone. Pulp capping with MTA plus HPE in rats showed superior dentin bridge formation, odontoblastic layers and dentinal tubules and lower inflammatory cell response, compared to the MTA alone group. This study demonstrates for the first time that the use of MTA with HPE promotes cell growth, differentiation and angiogenesis in HDPCs, which were associated with mTOR, MAPK and NF-κB pathways. Direct pulp capping with HPE plus MTA showed superior results when compared with MTA alone. Thus, the combination of MTA and HPE may be useful for regenerative endodontics.

  9. Proteomic Analysis of Dental Tissue Microsamples.

    Science.gov (United States)

    Mangum, Jonathan E; Kon, Jew C; Hubbard, Michael J

    2017-01-01

    Improved understanding of dental enamel development will benefit not only dentistry but also biomedicine more generally. Rat and mouse models of enamel development are relatively well characterized and experimentally powerful. However, the diminutive size of murine teeth makes them difficult to study using standard proteomics approaches. Here, we describe gel-based proteomic methods that enable parallel quantification, identification, and functional characterization of proteins from developing rat and mouse teeth. These refined methods are applicable to other scarce samples including human enamel defects.

  10. Neural Crest Stem Cells from Dental Tissues: A New Hope for Dental and Neural Regeneration

    Directory of Open Access Journals (Sweden)

    Gaskon Ibarretxe

    2012-01-01

    Full Text Available Several stem cell sources persist in the adult human body, which opens the doors to both allogeneic and autologous cell therapies. Tooth tissues have proven to be a surprisingly rich and accessible source of neural crest-derived ectomesenchymal stem cells (EMSCs, which may be employed to repair disease-affected oral tissues in advanced regenerative dentistry. Additionally, one area of medicine that demands intensive research on new sources of stem cells is nervous system regeneration, since this constitutes a therapeutic hope for patients affected by highly invalidating conditions such as spinal cord injury, stroke, or neurodegenerative diseases. However, endogenous adult sources of neural stem cells present major drawbacks, such as their scarcity and complicated obtention. In this context, EMSCs from dental tissues emerge as good alternative candidates, since they are preserved in adult human individuals, and retain both high proliferation ability and a neural-like phenotype in vitro. In this paper, we discuss some important aspects of tissue regeneration by cell therapy and point out some advantages that EMSCs provide for dental and neural regeneration. We will finally review some of the latest research featuring experimental approaches and benefits of dental stem cell therapy.

  11. Real-time in vivo imaging of dental tissue by means of optical coherence tomography (OCT)

    Science.gov (United States)

    Brandenburg, Roland; Haller, Bernd; Hauger, Christoph

    2003-11-01

    We have carried out real-time in vivo and in vitro imaging of human dental tissue in a clinical setting by means of optical coherence tomography (OCT). We have used a compact, commercial prototype OCT system applying for the first time a surgical microscope as a beam delivery system for investigations of dental tissue. We have imaged demineralised tissue, caries lesions, restored teeth and oral mucosa and demonstrate the detection of changes in tissue microstructure. We discuss the details of this system and its potential and limitations with respect to dental applications.

  12. Eugenol Toxicity in Human Dental Pulp Fibroblasts of Primary Teeth.

    Science.gov (United States)

    Escobar-García, Maria; Rodríguez-Contreras, Karen; Ruiz-Rodríguez, Socorro; Pierdant-Pérez, Mauricio; Cerda-Cristerna, Bernardino; Pozos-Guillén, Amaury

    2016-01-01

    The aim of the study was to determine the eugenol concentrations at which toxicity occurs in human dental pulp fibroblasts of primary teeth. Samples of primary dental pulp tissue were taken. Tissue samples were seeded by means of explant technique and used in the 4(th)-5th pass. Single Cell Gel Electrophoresis (Comet), phenazine MeThoSulfate (MTS), LIVE/DEAD Cell Viability/Toxicity and trypan blue assays for evaluation of the cytotoxicity of increasing concentrations of eugenol (0.06 to 810 μM) were performed. The results of toxicity tests showed toxic effects on dental pulp fibroblasts, even at very low concentrations of eugenol (0.06 μM). Very low concentrations of eugenol produce high toxicity in human dental pulp fibroblasts. All of the concentrations of eugenol that we evaluated produced high toxicity in human dental pulp fibroblasts of primary teeth.

  13. Denitrification in human dental plaque

    Directory of Open Access Journals (Sweden)

    Verstraete Willy

    2010-03-01

    Full Text Available Abstract Background Microbial denitrification is not considered important in human-associated microbial communities. Accordingly, metabolic investigations of the microbial biofilm communities of human dental plaque have focused on aerobic respiration and acid fermentation of carbohydrates, even though it is known that the oral habitat is constantly exposed to nitrate (NO3- concentrations in the millimolar range and that dental plaque houses bacteria that can reduce this NO3- to nitrite (NO2-. Results We show that dental plaque mediates denitrification of NO3- to nitric oxide (NO, nitrous oxide (N2O, and dinitrogen (N2 using microsensor measurements, 15N isotopic labelling and molecular detection of denitrification genes. In vivo N2O accumulation rates in the mouth depended on the presence of dental plaque and on salivary NO3- concentrations. NO and N2O production by denitrification occurred under aerobic conditions and was regulated by plaque pH. Conclusions Increases of NO concentrations were in the range of effective concentrations for NO signalling to human host cells and, thus, may locally affect blood flow, signalling between nerves and inflammatory processes in the gum. This is specifically significant for the understanding of periodontal diseases, where NO has been shown to play a key role, but where gingival cells are believed to be the only source of NO. More generally, this study establishes denitrification by human-associated microbial communities as a significant metabolic pathway which, due to concurrent NO formation, provides a basis for symbiotic interactions.

  14. Human serum promotes osteogenic differentiation of human dental pulp stem cells in vitro and in vivo

    National Research Council Canada - National Science Library

    Pisciotta, Alessandra; Riccio, Massimo; Carnevale, Gianluca; Beretti, Francesca; Gibellini, Lara; Maraldi, Tullia; Cavallini, Gian Maria; Ferrari, Adriano; Bruzzesi, Giacomo; De Pol, Anto

    2012-01-01

    Human dental pulp is a promising alternative source of stem cells for cell-based tissue engineering in regenerative medicine, for the easily recruitment with low invasivity for the patient and for the...

  15. Human dental pulp stem cells: Applications in future regenerative medicine

    Science.gov (United States)

    Potdar, Pravin D; Jethmalani, Yogita D

    2015-01-01

    Stem cells are pluripotent cells, having a property of differentiating into various types of cells of human body. Several studies have developed mesenchymal stem cells (MSCs) from various human tissues, peripheral blood and body fluids. These cells are then characterized by cellular and molecular markers to understand their specific phenotypes. Dental pulp stem cells (DPSCs) are having a MSCs phenotype and they are differentiated into neuron, cardiomyocytes, chondrocytes, osteoblasts, liver cells and β cells of islet of pancreas. Thus, DPSCs have shown great potentiality to use in regenerative medicine for treatment of various human diseases including dental related problems. These cells can also be developed into induced pluripotent stem cells by incorporation of pluripotency markers and use for regenerative therapies of various diseases. The DPSCs are derived from various dental tissues such as human exfoliated deciduous teeth, apical papilla, periodontal ligament and dental follicle tissue. This review will overview the information about isolation, cellular and molecular characterization and differentiation of DPSCs into various types of human cells and thus these cells have important applications in regenerative therapies for various diseases. This review will be most useful for postgraduate dental students as well as scientists working in the field of oral pathology and oral medicine. PMID:26131314

  16. Human dental pulp stem cells: Applications in future regenerative medicine.

    Science.gov (United States)

    Potdar, Pravin D; Jethmalani, Yogita D

    2015-06-26

    Stem cells are pluripotent cells, having a property of differentiating into various types of cells of human body. Several studies have developed mesenchymal stem cells (MSCs) from various human tissues, peripheral blood and body fluids. These cells are then characterized by cellular and molecular markers to understand their specific phenotypes. Dental pulp stem cells (DPSCs) are having a MSCs phenotype and they are differentiated into neuron, cardiomyocytes, chondrocytes, osteoblasts, liver cells and β cells of islet of pancreas. Thus, DPSCs have shown great potentiality to use in regenerative medicine for treatment of various human diseases including dental related problems. These cells can also be developed into induced pluripotent stem cells by incorporation of pluripotency markers and use for regenerative therapies of various diseases. The DPSCs are derived from various dental tissues such as human exfoliated deciduous teeth, apical papilla, periodontal ligament and dental follicle tissue. This review will overview the information about isolation, cellular and molecular characterization and differentiation of DPSCs into various types of human cells and thus these cells have important applications in regenerative therapies for various diseases. This review will be most useful for postgraduate dental students as well as scientists working in the field of oral pathology and oral medicine.

  17. Extracellular matrix of dental pulp stem cells: Applications in pulp tissue engineering using somatic MSCs

    Directory of Open Access Journals (Sweden)

    Sriram eRavindran

    2014-01-01

    Full Text Available Dental Caries affects approximately 90% of the world’s population. At present, the clinical treatment for dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality. Tissue engineering can potentially solve this problem by enabling regeneration of a functional pulp tissue. Dental pulp stem cells (DPSCs have been shown to be an excellent source for pulp regeneration. However, limited availability of these cells hinders its potential for clinical translation. We have investigated the possibility of using somatic mesenchymal stem cells from other sources for dental pulp tissue regeneration using a biomimetic dental pulp extracellular matrix (ECM incorporated scaffold. Human periodontal ligament stem cells (PDLSCs and human bone marrow stromal cells (HMSCs were investigated for their ability to differentiate towards an odontogenic lineage. In vitro real-time PCR results coupled with histological and immunohistochemical examination of the explanted tissues confirmed the ability of PDLSCs and HMSCs to form a vascularized pulp-like tissue. These findings indicate that the dental pulp stem derived ECM scaffold stimulated odontogenic differentiation of PDLSCs and HMSCs without the need for exogenous addition of growth and differentiation factors. This study represents a translational perspective toward possible therapeutic application of using a combination of somatic stem cells and extracellular matrix for pulp regeneration.

  18. Dental Tissue — New Source for Stem Cells

    Directory of Open Access Journals (Sweden)

    Vladimir Petrovic

    2009-01-01

    Full Text Available Stem cells have been isolated from many tissues and organs, including dental tissue. Five types of dental stem cells have been established: dental pulp stem cells, stem cells from exfoliated deciduous teeth, stem cells from apical papilla, periodontal ligament stem cells, and dental follicle progenitor cells. The main characteristics of dental stem cells are their potential for multilineage differentiation and self-renewal capacity. Dental stem cells can differentiate into odontoblasts, adipocytes, neuronal-like cells, glial cells, osteoblasts, chondrocytes, melanocytes, myotubes, and endothelial cells. Possible application of these cells in various fields of medicine makes them good candidates for future research as a new, powerful tool for therapy. Although the possible use of these cells in therapeutic purposes and tooth tissue engineering is still in the beginning stages, the results are promising. The efforts made in the research of dental stem cells have clarified many mechanisms underlying the biological processes in which these cells are involved. This review will focus on the new findings in the field of dental stem cell research and on their potential use in the therapy of various disorders.

  19. Soft tissue sealing around dental implants based on histological interpretation.

    Science.gov (United States)

    Atsuta, Ikiru; Ayukawa, Yasunori; Kondo, Ryosuke; Oshiro, Wakana; Matsuura, Yuri; Furuhashi, Akihiro; Tsukiyama, Yoshihiro; Koyano, Kiyoshi

    2016-01-01

    The aim of this study was to provide an overview on the biology and soft tissue sealing around dental implants and teeth. This is a narrative review performed through scientific articles published between 1977 and 2014, indexed in MEDLINE and PubMed databases. The study selected articles that focused on epithelial sealing around dental implant or teeth with cell biology and histology of soft tissue. Implant therapy has been widely applied in dental rehabilitation for many years, with predictable long-term results. The longevity and functionality of dental implants is dependent on both osseointegration around the implant body and the establishment of a soft tissue barrier that protects the underlying hard tissue structures and the implant itself. The health and stability of the peri-implant mucosa also affects the esthetics of the implant. The healing and maintenance of the epithelial and connective tissues around implants are increasingly recognized as being fundamental to implant success. However, there has been little research into the function or formation of the soft tissue seal around dental implants, and the roles of this unique mucosal interface remain unclear. This narrative review explores the extent of the current knowledge of soft tissue barriers around implants from both a basic and clinical perspective, and aims to consolidate this knowledge and highlight the most pertinent questions relating to this area of research. Copyright © 2015 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  20. Biomechanical study of the bone tissue with dental implants interaction

    Directory of Open Access Journals (Sweden)

    Navrátil P.

    2011-12-01

    Full Text Available The article deals with the stress-strain analysis of human mandible in the physiological state and after the dental implant application. The evaluation is focused on assessing of the cancellous bone tissue modeling-level. Three cancellous bone model-types are assessed: Non-trabecular model with homogenous isotropic material, nontrabecular model with inhomogeneous material obtained from computer tomography data using CT Data Analysis software, and trabecular model built from mandible section image. Computational modeling was chosen as the most suitable solution method and the solution on two-dimensional level was carried out. The results show that strain is more preferable value than stress in case of evaluation of mechanical response in cancellous bone. The non-trabecular model with CT-obtained material model is not acceptable for stress-strain analysis of the cancellous bone for singularities occurring on interfaces of regions with different values of modulus of elasticity.

  1. Bioengineering of Dental Tissues: Bibliometric Analysis 2000-2011.

    Directory of Open Access Journals (Sweden)

    Sebastián Zamorano

    2014-03-01

    Full Text Available Introduction: There has been a noticeable increase in experimental use and therapies based on stem cells over recent years. Nevertheless, there is a lack of information about this progress in the dental field, which makes it difficult to trace development and design policies. The purpose of this study, as a first approach to the subject, is to determine a bibliometric profile for the investigation related to bioengineering of dental tissue at a worldwide scale, based on the MEDLINE database, for the period 2000-2011. Methodology: A bibliometric study was carried out. Every article indexed in the MEDLINE database and associated with the terms “stem cells” and “tooth regeneration” for the period 2000-2011 was included. The analyzed variables were publishing date, country of origin, language and publication type (original or review, journal, author, associated university and tissue source (human or animal. Results: For the entire period included in the study, 257 articles were found. Of these, 149 corresponded to original Works published in English; 5 in other languages; 92 comprised literature reviews in English, 9 in other languages and 2 publications were included in the “others” category. The countries with the highest research productivity were the United States (24.51%, Japan (20.62% and China (17.90%, while Brazil (3.9% was the only Latin-American country found in the list. Animal tissues were used in 59.09% of them. The most productive authors were Ueda M (17 and Jin Y (11, whereas Fourth Military University (13, University of Tokyo (12 and Capital Medical University (10 had the largest number of publications. Conclusion: The United States, Japan and China concentrate about two thirds of the production. Latin-America was represented only by Brazil.

  2. Nigerian dental technology students and human immunodeficiency ...

    African Journals Online (AJOL)

    Background: The rehabilitative dental care is important for maintaining adequate nutrition, guarding against wasting syndrome and malnutrition among human immunodeficiency virus (HIV)‑infected individuals. Aim: The aim of this study is to determine the Nigerian dental technology students' knowledge and ...

  3. Dental hard tissue characterization using laser-based ultrasonics

    Science.gov (United States)

    Blodgett, David W.; Massey, Ward L.

    2003-07-01

    Dental health care and research workers require a means of imaging the structures within teeth in vivo. One critical need is the detection of tooth decay in its early stages. If decay can be detected early enough, the process can be monitored and interventional procedures, such as fluoride washes and controlled diet, can be initiated to help re-mineralize the tooth. Currently employed x-ray imaging is limited in its ability to visualize interfaces and incapable of detecting decay at a stage early enough to avoid invasive cavity preparation followed by a restoration. To this end, non-destructive and non-contact in vitro measurements on extracted human molars using laser-based ultrasonics are presented. Broadband ultrasonic waves are excited in the extracted sections by using a pulsed carbon-dioxide (CO2) laser operating in a region of high optical absorption in the dental hard tissues. Optical interferometric detection of the ultrasonic wave surface displacements in accomplished with a path-stabilized Michelson-type interferometer. Results for bulk and surface in-vitro characterization of caries are presented on extracted molars with pre-existing caries.

  4. [Human brown adipose tissue].

    Science.gov (United States)

    Virtanen, Kirsi A; Nuutila, Pirjo

    2015-01-01

    Adult humans have heat-producing and energy-consuming brown adipose tissue in the clavicular region of the neck. There are two types of brown adipose cells, the so-called classic and beige adipose cells. Brown adipose cells produce heat by means of uncoupler protein 1 (UCP1) from fatty acids and sugar. By applying positron emission tomography (PET) measuring the utilization of sugar, the metabolism of brown fat has been shown to multiply in the cold, presumably influencing energy consumption. Active brown fat is most likely present in young adults, persons of normal weight and women, least likely in obese persons.

  5. A Hyaluronan-Based Scaffold for the in Vitro Construction of Dental Pulp-Like Tissue

    Directory of Open Access Journals (Sweden)

    Letizia Ferroni

    2015-03-01

    Full Text Available Dental pulp tissue supports the vitality of the tooth, but it is particularly vulnerable to external insults, such as mechanical trauma, chemical irritation or microbial invasion, which can lead to tissue necrosis. In the present work, we present an endodontic regeneration method based on the use of a tridimensional (3D hyaluronan scaffold and human dental pulp stem cells (DPSCs to produce a functional dental pulp-like tissue in vitro. An enriched population of DPSCs was seeded onto hyaluronan-based non-woven meshes in the presence of differentiation factors to induce the commitment of stem cells to neuronal, glial, endothelial and osteogenic phenotypes. In vitro experiments, among which were gene expression profiling and immunofluorescence (IF staining, proved the commitment of DPSCs to the main components of dental pulp tissue. In particular, the hyaluronan-DPSCs construct showed a dental pulp-like morphology consisting of several specialized cells growing inside the hyaluronan fibers. Furthermore, these constructs were implanted into rat calvarial critical-size defects. Histological analyses and gene expression profiling performed on hyaluronan-DPSCs grafts showed the regeneration of osteodentin-like tissue. Altogether, these data suggest the regenerative potential of the hyaluronan-DPSC engineered tissue.

  6. Dental hard tissue drilling by longitudinally excited CO2 laser

    Science.gov (United States)

    Uno, Kazuyuki; Yamamoto, Takuya; Akitsu, Tetsuya; Jitsuno, Takahisa

    2017-07-01

    We developed a longitudinally excited CO2 laser with a long optical cavity and investigated the drilling characteristics of dental hard tissue. The CO2 laser was very simple and consisted of a 45-cm-long alumina ceramic pipe with an inner diameter of 13 mm, a pulse power supply, a step-up transformer, a storage capacitance, a spark gap, and a long optical cavity with a cavity length of 175 cm. The CO2 laser produced a short pulse that had a spike pulse with the width of 337 ns and the energy of 1.9 mJ, a pulse tail with the length of 180 μs and the energy of 37.6 mJ, and a doughnut-like beam. In the investigation, a sample was a natural drying human tooth (enamel and dentine). In a processing system, a ZnSe focusing lens with the focal length of 50 mm was used and the location of the focal plane was that of the sample surface. In 1 pulse irradiation, the drilling characteristics depended on the fluence was investigated. In the enamel and dentin drilling, the drilling depth increased with the fluence. The 1 pulse irradiation with the fluence of 21.5 J/cm2 produced the depth of 79.3 μm in the enamel drilling, and the depth of 152.7 μm in the dentin drilling. The short-pulse CO2 laser produced a deeper drilling depth at a lower fluence than long-pulse CO2 lasers in dental hard tissue processing.

  7. Lack of cytotoxicity by Trustwater Ecasol™ used to maintain good quality dental unit waterline output water in keratinocyte monolayer and reconstituted human oral epithelial tissue models.

    LENUS (Irish Health Repository)

    Boyle, M A

    2010-11-01

    We previously showed that residual treatment of dental chair unit (DCU) supply water using the electrochemically-activated solution Trustwater Ecasol™ (2.5 ppm) provided an effective long-term solution to the problem of dental unit waterline (DUWL) biofilm resulting in DUWL output water quality consistently superior to potable water.

  8. Pulp and periodontal tissue repair - regeneration or tissue metaplasia after dental trauma. A review.

    Science.gov (United States)

    Andreasen, Jens O

    2012-02-01

    Healing subsequent to dental trauma is known to be very complex, a result explained by the variability of the types of dental trauma (six luxations, nine fracture types, and their combinations). On top of that, at least 16 different cellular systems get involved in more severe trauma types each of them with a different potential for healing with repair, i.e. (re-establishment of tissue continuity without functional restitution) and regeneration (where the injured or lost tissue is replaced with new tissue with identical tissue anatomy and function) and finally metaplasia (where a new type of tissue replaces the injured). In this study, a review is given of the impact of trauma to various dental tissues such as alveolar bone, periodontal ligament, cementum, Hertvigs epithelial root sheath, and the pulp. © 2011 John Wiley & Sons A/S.

  9. Pulp and periodontal tissue repair - regeneration or tissue metaplasia after dental trauma. A review

    DEFF Research Database (Denmark)

    Andreasen, Jens O

    2012-01-01

    Healing subsequent to dental trauma is known to be very complex, a result explained by the variability of the types of dental trauma (six luxations, nine fracture types, and their combinations). On top of that, at least 16 different cellular systems get involved in more severe trauma types each...... of tissue replaces the injured). In this study, a review is given of the impact of trauma to various dental tissues such as alveolar bone, periodontal ligament, cementum, Hertvigs epithelial root sheath, and the pulp....

  10. Differential reduction of reactive oxygen species by human tissue ...

    Indian Academy of Sciences (India)

    Swati Paliwal

    2017-06-24

    Jun 24, 2017 ... Clinical trials using human Mesenchymal Stem Cells (MSCs) have shown promising results in the treatment of various diseases. Different tissue sources, such as bone marrow, adipose tissue, dental pulp and umbilical cord, are being routinely used in regenerative medicine. MSCs are known to reduce ...

  11. Differential reduction of reactive oxygen species by human tissue ...

    Indian Academy of Sciences (India)

    Clinical trials using human Mesenchymal Stem Cells (MSCs) have shown promising results in the treatment of variousdiseases. Different tissue sources, such as bone marrow, adipose tissue, dental pulp and umbilical cord, are being routinelyused in regenerative medicine. MSCs are known to reduce increased oxidative ...

  12. Soft tissue wound healing around teeth and dental implants.

    Science.gov (United States)

    Sculean, Anton; Gruber, Reinhard; Bosshardt, Dieter D

    2014-04-01

    To provide an overview on the biology and soft tissue wound healing around teeth and dental implants. This narrative review focuses on cell biology and histology of soft tissue wounds around natural teeth and dental implants. The available data indicate that: (a) Oral wounds follow a similar pattern. (b) The tissue specificities of the gingival, alveolar and palatal mucosa appear to be innately and not necessarily functionally determined. (c) The granulation tissue originating from the periodontal ligament or from connective tissue originally covered by keratinized epithelium has the potential to induce keratinization. However, it also appears that deep palatal connective tissue may not have the same potential to induce keratinization as the palatal connective tissue originating from an immediately subepithelial area. (d) Epithelial healing following non-surgical and surgical periodontal therapy appears to be completed after a period of 7–14 days. Structural integrity of a maturing wound between a denuded root surface and a soft tissue flap is achieved at approximately 14-days post-surgery. (e) The formation of the biological width and maturation of the barrier function around transmucosal implants requires 6–8 weeks of healing. (f) The established peri-implant soft connective tissue resembles a scar tissue in composition, fibre orientation, and vasculature. (g) The peri-implant junctional epithelium may reach a greater final length under certain conditions such as implants placed into fresh extraction sockets versus conventional implant procedures in healed sites. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Dental Considerations for Age Determination in humans

    OpenAIRE

    Althaf Hussain Chalkoo

    2006-01-01

    The basis for dental identification is the theory that human dentition is never the same in any two individuals. Although teeth are resistant to environmental insults during life they are susceptible to physiological and pathological changes. As a result teeth may have restorations which may alter their original morphology. Dental age estimation makes use of morphologic, radiographic, histological and biochemical methods- to estimate age dependant changes in teeth.

  14. Stem Cell-Based Dental Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Petar Zivkovic

    2010-01-01

    Full Text Available The development of biological and biomaterial sciences profiled tissue engineering as a new and powerful tool for biological replacement of organs. The combination of stem cells and suitable scaffolds is widely used in experiments today, in order to achieve partial or whole organ regeneration. This review focuses on the use of tissue engineering strategies in tooth regeneration, using stem cells and stem cells/scaffold constructs. Although whole tooth regeneration is still not possible, there are promising results. However, to achieve this goal, it is important to understand and further explore the mechanisms underlying tooth development. Only then will we be able to mimic the natural processes with the use of stem cells and tissue engineering techniques.

  15. Purified Human Dental Pulp Stem Cells Promote Osteogenic Regeneration.

    Science.gov (United States)

    Yasui, T; Mabuchi, Y; Toriumi, H; Ebine, T; Niibe, K; Houlihan, D D; Morikawa, S; Onizawa, K; Kawana, H; Akazawa, C; Suzuki, N; Nakagawa, T; Okano, H; Matsuzaki, Y

    2016-02-01

    Human dental pulp stem/progenitor cells (hDPSCs) are attractive candidates for regenerative therapy because they can be easily expanded to generate colony-forming unit-fibroblasts (CFU-Fs) on plastic and the large cell numbers required for transplantation. However, isolation based on adherence to plastic inevitably changes the surface marker expression and biological properties of the cells. Consequently, little is currently known about the original phenotypes of tissue precursor cells that give rise to plastic-adherent CFU-Fs. To better understand the in vivo functions and translational therapeutic potential of hDPSCs and other stem cells, selective cell markers must be identified in the progenitor cells. Here, we identified a dental pulp tissue-specific cell population based on the expression profiles of 2 cell-surface markers LNGFR (CD271) and THY-1 (CD90). Prospectively isolated, dental pulp-derived LNGFR(Low+)THY-1(High+) cells represent a highly enriched population of clonogenic cells--notably, the isolated cells exhibited long-term proliferation and multilineage differentiation potential in vitro. The cells also expressed known mesenchymal cell markers and promoted new bone formation to heal critical-size calvarial defects in vivo. These findings suggest that LNGFR(Low+)THY-1(High+) dental pulp-derived cells provide an excellent source of material for bone regenerative strategies. © International & American Associations for Dental Research 2015.

  16. Automated classification and visualization of healthy and pathological dental tissues based on near-infrared hyper-spectral imaging

    Science.gov (United States)

    Usenik, Peter; Bürmen, Miran; Vrtovec, Tomaž; Fidler, Aleš; Pernuš, Franjo; Likar, Boštjan

    2011-03-01

    Despite major improvements in dental healthcare and technology, dental caries remains one of the most prevalent chronic diseases of modern society. The initial stages of dental caries are characterized by demineralization of enamel crystals, commonly known as white spots which are difficult to diagnose. If detected early enough, such demineralization can be arrested and reversed by non-surgical means through well established dental treatments (fluoride therapy, anti-bacterial therapy, low intensity laser irradiation). Near-infrared (NIR) hyper-spectral imaging is a new promising technique for early detection of demineralization based on distinct spectral features of healthy and pathological dental tissues. In this study, we apply NIR hyper-spectral imaging to classify and visualize healthy and pathological dental tissues including enamel, dentin, calculus, dentin caries, enamel caries and demineralized areas. For this purpose, a standardized teeth database was constructed consisting of 12 extracted human teeth with different degrees of natural dental lesions imaged by NIR hyper-spectral system, X-ray and digital color camera. The color and X-ray images of teeth were presented to a clinical expert for localization and classification of the dental tissues, thereby obtaining the gold standard. Principal component analysis was used for multivariate local modeling of healthy and pathological dental tissues. Finally, the dental tissues were classified by employing multiple discriminant analysis. High agreement was observed between the resulting classification and the gold standard with the classification sensitivity and specificity exceeding 85 % and 97 %, respectively. This study demonstrates that NIR hyper-spectral imaging has considerable diagnostic potential for imaging hard dental tissues.

  17. Imunohistological aspects of the tissue around dental implants

    Science.gov (United States)

    Nimigean, Victor; Nimigean, Vanda R.; Sǎlǎvǎstru, Dan I.; Moraru, Simona; BuÅ£incu, Lavinia; Ivaşcu, Roxana V.; Poll, Alexandru

    2016-03-01

    Objectives: study of soft and hard tissues around implants. Material and methods: For the immunohistochemical and histological study of the implant/soft tissue interface, we examined pieces of peri-implant mucosa harvested from 35 patients. The implant/bone interface was assessed using histologic and histomorphometric examination of hard tissues around unloaded, early loaded or delayed loaded dental implants with pre-established design, with a sandblasted and acid-etched surface, placed both in extraction sockets, or after bone healing following tooth removal. This study was performed on 9 common race dogs. Results: The histological study of the implant/soft tissue interface showed regenerative modifications and moderate chronic subepithelial inflammatory reactions. Immunohistochemical evaluation of the soft tissue biopsies revealed the presence of specific immunocompetent cells and proteins of the matrix metalloproteinase (MMP) expression. Bone-implants contacts were more obvious in the apical half of the implants and at the edges of the threads, than between them. A mature, lamelliform bone containing lacunae with osteocytes and lack of connective tissue were noticed around implants that were late placed and loaded. The new-formed bone was also abundant in the crestal zone, not only in the apical part of the implants. Conclusions: A thorough understanding of the microstructure of dental implant/soft and hard tissue interface will improve the longevity of osseointegrated implants.

  18. Improvement of In Vitro Osteogenic Potential through Differentiation of Induced Pluripotent Stem Cells from Human Exfoliated Dental Tissue towards Mesenchymal-Like Stem Cells

    Directory of Open Access Journals (Sweden)

    Felipe Augusto Andre Ishiy

    2015-01-01

    Full Text Available Constraints for the application of MSCs for bone reconstruction include restricted self-renewal and limited cell amounts. iPSC technology presents advantages over MSCs, providing homogeneous cellular populations with prolonged self-renewal and higher plasticity. However, it is unknown if the osteogenic potential of iPSCs differs from that of MSCs and if it depends on the iPSCs originating cellular source. Here, we compared the in vitro osteogenesis between stem cells from human deciduous teeth (SHED and MSC-like cells from iPSCs from SHED (iPS-SHED and from human dermal fibroblasts (iPS-FIB. MSC-like cells from iPS-SHED and iPS-FIB displayed fibroblast-like morphology, downregulation of pluripotency markers and upregulation of mesenchymal markers. Comparative in vitro osteogenesis analysis showed higher osteogenic potential in MSC-like cells from iPS-SHED followed by MSC-like cells from iPS-FIB and SHED. CD105 expression, reported to be inversely correlated with osteogenic potential in MSCs, did not display this pattern, considering that SHED presented lower CD105 expression. Higher osteogenic potential of MSC-like cells from iPS-SHED may be due to cellular homogeneity and/or to donor tissue epigenetic memory. Our findings strengthen the rationale for the use of iPSCs in bone bioengineering. Unveiling the molecular basis behind these differences is important for a thorough use of iPSCs in clinical scenarios.

  19. Biomimetic extracellular matrix mediated somatic stem cell differentiation: applications in dental pulp tissue regeneration

    OpenAIRE

    Sriram eRavindran; ANNE eGEORGE

    2015-01-01

    Dental caries is one of the most widely prevalent infectious diseases in the world. It affects more than half of the world’s population. The current treatment for necrotic dental pulp tissue arising from dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality making it prone for secondary infections. Over the past decade, several tissue-engineering approaches have attempted regeneration of the dental pulp tissue. Although several studies have...

  20. Can degradation products released from dental implants affect peri-implant tissues?

    Science.gov (United States)

    Noronha Oliveira, M; Schunemann, W V H; Mathew, M T; Henriques, B; Magini, R S; Teughels, W; Souza, J C M

    2017-08-02

    This study aimed to assess the literature available on the effects, on peri-implant tissues, of degradation products released from dental implants as a consequence of therapeutic treatment for peri-implantitis and/or of wear-corrosion of titanium. A literature review of the PubMed medline database was performed up to December 31, 2016. The following search terms were used: "titanium wear and dental implant"; "titanium corrosion and dental implant"; "bio-tribocorrosion"; "peri-implantitis"; "treatment of peri-implantitis"; "titanium particles release and dental implant"; and "titanium ion release and dental implant". The keywords were applied to the database in different combinations without limits of time period or type of work. In addition, the reference lists of relevant articles were searched for further studies. Seventy-nine relevant scientific articles on the topic were retrieved. The results showed that pro-inflammatory cytokines, infiltration of inflammatory response cells and activation of the osteoclasts activity are stimulated in peri-implant tissues in the presence of metal particles and ions. Moreover, degenerative changes were reported in macrophages and neutrophils that phagocytosed titanium microparticles, and mutations occurred in human cells cultured in medium containing titanium-based nanoparticles. Debris released from the degradation of dental implants has cytotoxic and genotoxic potential for peri-implant tissues. Thus, the amount and physicochemical properties of the degradation products determine the magnitude of the detrimental effect on peri-implant tissues. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Fabrication and characterisation of composites materials similar optically and in composition to native dental tissues

    Science.gov (United States)

    Seredin, P. V.; Goloshchapov, D. L.; Prutskij, T.; Ippolitov, Yu. A.

    This study investigated the luminescence characteristics of synthesized biocomposites similar in organic and mineral composition to native dental tissues, enamel and dentine. It was found that the luminescence spectrum of intact enamel is similar to that of calcium hydroxyapatite (HAP) used to synthesize biomimetic materials. Despite the morphological differences between the synthesized biocomposite and native tissue, their luminescence spectra suggest that the shape of the luminescence spectrum is more influenced by defects in the crystal structure of the employed hydroxyapatite than by the structure and order of the apatite nanocrystals typical of native dental tissues. The spectrum of intact human dentine possessed a wider luminescence band, unlike that of enamel, with a maximum typical of intact dentine. Analysis of the spectra of biomimetic material modelling the properties of dentine indicated that both the organic and non-organic components contribute to their luminescence.

  2. RAMAN-SPECTRA OF HUMAN DENTAL CALCULUS

    NARCIS (Netherlands)

    TSUDA, H; ARENDS, J

    1993-01-01

    Raman spectra of human dental calculus have been observed for the first time by use of micro-Raman spectroscopy. The spectral features of calculus were influenced easily by heating caused by laser irradiation. Therefore, the measurements were carried out at relatively low power (5 mW, 1-mu m spot

  3. Ability of healthy and inflamed human dental pulp to reduce hydrogen peroxide.

    Science.gov (United States)

    Esposito, Paola; Varvara, Giuseppe; Murmura, Giovanna; Terlizzi, Antonio; Caputi, Sergio

    2003-10-01

    This study examined the defensive ability of human dental pulp against H2O2 in healthy and reversible and irreversible pulpitis tissues through determination of catalase activity by spectrophotometric methods. Thirty-five systemically healthy patients were donors of the pulp tissue, and pulp conditions were assessed using clinical and X-ray evaluations. Catalase activity was 1.61 +/- 0.23 U mg(-1) protein in the healthy tissues, 2.99 +/- 0.45 U mg(-1) protein in the reversible pulpitis tissues, and 2.44 +/- 467 mU mg(-1) protein in the irreversible pulpitis tissues. All differences between the groups were statistically significant. These results point to a role for catalase during dental pulp inflammation in humans, and therefore demonstrate an inherent biological defense system against reactive oxidants in human dental pulp.

  4. Hard tissue formation in a porous HA/TCP ceramic scaffold loaded with stromal cells derived from dental pulp and bone marrow.

    NARCIS (Netherlands)

    Zhang, W.; Walboomers, X.F.; Osch, G.J.V.M. van; Dolder, J. van den; Jansen, J.A.

    2008-01-01

    The aim of this study was to compare the ability of hard tissue regeneration of four types of stem cells or precursors under both in vitro and in vivo situations. Primary cultures of rat bone marrow, rat dental pulp, human bone marrow, and human dental pulp cells were seeded onto a porous ceramic

  5. Human trafficking and the dental professional.

    Science.gov (United States)

    O'Callaghan, Michael G

    2012-05-01

    "Human trafficking" is a term for a modern form of slavery. It is a criminal human rights violation and a significant health issue. Dental professionals can assist in recognizing victims of trafficking. The author conducted a PubMed search of the English-language literature through May 2011, which yielded no articles meeting the search criteria "dentistry" and "human trafficking prostitution." Given these results, the author reviewed articles published in medical journals, reports from both governmental and nongovernmental agencies and lay literature. The author examines the present state of human trafficking and provides information--including specific questions to ask--to help dentists identify victims. In addition, the author suggests means of notifying authorities and assisting trafficking victims. He also examines the health care needs of these patients. Human trafficking is a global problem, with thousands of victims in the United States, including many women and children. Dentists have a responsibility to act for the benefit of others, which includes detecting signs of abuse and neglect. Dental professionals are on the front lines with respect to encountering and identifying potential victims who seek dental treatment. Dentists can combat human trafficking by becoming informed and by maintaining vigilance in their practices.

  6. Metal elements in tissue with dental peri-implantitis: a pilot study.

    Science.gov (United States)

    Fretwurst, Tobias; Buzanich, Guenter; Nahles, Susanne; Woelber, Johan Peter; Riesemeier, Heinrich; Nelson, Katja

    2016-09-01

    Dental peri-implantitis is characterized by a multifactorial etiology. The role of metal elements as an etiological factor for peri-implantitis is still unclear. The aim of this study was to investigate the incidence of metal elements in bone and mucosal tissues around dental Grade 4 CP titanium implants with signs of peri-implantitis in human patients. In this prospective pilot study, all patients were enrolled consecutively in two study centers. Bone and soft tissue samples of patients with peri-implantitis with indication for explantation were analyzed for the incidence of different elements (Ca, P, Ti, Fe) by means of synchrotron radiation X-ray fluorescence spectroscopy (SRXRF) and polarized light microscopy (PLM). The existence of macrophages and lymphocytes in the histologic specimens was analyzed. Biopsies of 12 patients (seven bone samples, five mucosal samples) were included and analyzed. In nine of the 12 samples (75%), the SRXRF examination revealed the existence of titanium (Ti) and an associated occurrence with Iron (Fe). Metal particles were detected in peri-implant soft tissue using PLM. In samples with increased titanium concentration, lymphocytes were detected, whereas M1 macrophages were predominantly seen in samples with metal particles. Titanium and Iron elements were found in soft and hard tissue biopsies retrieved from peri-implantitis sites. Further histologic and immunohistochemical studies need to clarify which specific immune reaction metal elements/particles induce in dental peri-implant tissue. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Improved classification and visualization of healthy and pathological hard dental tissues by modeling specular reflections in NIR hyperspectral images

    Science.gov (United States)

    Usenik, Peter; Bürmen, Miran; Fidler, Aleš; Pernuš, Franjo; Likar, Boštjan

    2012-03-01

    Despite major improvements in dental healthcare and technology, dental caries remains one of the most prevalent chronic diseases of modern society. The initial stages of dental caries are characterized by demineralization of enamel crystals, commonly known as white spots, which are difficult to diagnose. Near-infrared (NIR) hyperspectral imaging is a new promising technique for early detection of demineralization which can classify healthy and pathological dental tissues. However, due to non-ideal illumination of the tooth surface the hyperspectral images can exhibit specular reflections, in particular around the edges and the ridges of the teeth. These reflections significantly affect the performance of automated classification and visualization methods. Cross polarized imaging setup can effectively remove the specular reflections, however is due to the complexity and other imaging setup limitations not always possible. In this paper, we propose an alternative approach based on modeling the specular reflections of hard dental tissues, which significantly improves the classification accuracy in the presence of specular reflections. The method was evaluated on five extracted human teeth with corresponding gold standard for 6 different healthy and pathological hard dental tissues including enamel, dentin, calculus, dentin caries, enamel caries and demineralized regions. Principal component analysis (PCA) was used for multivariate local modeling of healthy and pathological dental tissues. The classification was performed by employing multiple discriminant analysis. Based on the obtained results we believe the proposed method can be considered as an effective alternative to the complex cross polarized imaging setups.

  8. Regeneration of Dental-Pulp-like Tissue by Chemotaxis-Induced Cell Homing

    Science.gov (United States)

    Kim, Jin Y.; Xin, Xuejun; Moioli, Eduardo K.; Chung, Jenny; Lee, Chang Hun; Chen, Mo; Fu, Susan Y.; Koch, Peter D.

    2010-01-01

    Tooth infections or injuries involving dental pulp are treated routinely by root canal therapy. Endodontically treated teeth are devitalized, susceptible to re-infections, fractures, and subsequent tooth loss. Here, we report regeneration of dental-pulp-like tissue by cell homing and without cell transplantation. Upon in vivo implantation of endodontically treated real-size, native human teeth in mouse dorsum for the tested 3 weeks, delivery of basic fibroblast growth factor and/or vascular endothelial growth factor (bFGF and/or VEGF) yielded re-cellularized and revascularized connective tissue that integrated to native dentinal wall in root canals. Further, combined delivery of bFGF, VEGF, or platelet-derived growth factor (PDGF) with a basal set of nerve growth factor (NGF) and bone morphogenetic protein-7 (BMP7) generated cellularized and vascularized tissues positive of VEGF antibody staining and apparent neo-dentin formation over the surface of native dentinal wall in some, but not all, endodontically treated teeth. Newly formed dental pulp tissue appeared dense with disconnected cells surrounded by extracellular matrix. Erythrocyte-filled blood vessels were present with endothelial-like cell lining. Reconstructed, multiple microscopic images showed complete fill of dental-pulp-like tissue in the entire root canal from root apex to pulp chamber with tissue integration to dentinal wall upon delivery of bFGF, VEGF, or PDGF with a basal set of NGF and BMP7. Quantitative ELISA showed that combinatory delivery of bFGF, VEGF, or PDGF with basal NGF and BMP7 elaborated von Willerbrand factor, dentin sialoprotein, and NGF. These findings represent the first demonstration of regenerated dental-pulp-like tissue in endodontically treated root canals of real-size, native human teeth. The present chemotaxis-based approach has potent cell homing effects for re-cellularization and revascularization in endodontically treated root canals in vivo, although in an ectopic model

  9. Regeneration of dental-pulp-like tissue by chemotaxis-induced cell homing.

    Science.gov (United States)

    Kim, Jin Y; Xin, Xuejun; Moioli, Eduardo K; Chung, Jenny; Lee, Chang Hun; Chen, Mo; Fu, Susan Y; Koch, Peter D; Mao, Jeremy J

    2010-10-01

    Tooth infections or injuries involving dental pulp are treated routinely by root canal therapy. Endodontically treated teeth are devitalized, susceptible to re-infections, fractures, and subsequent tooth loss. Here, we report regeneration of dental-pulp-like tissue by cell homing and without cell transplantation. Upon in vivo implantation of endodontically treated real-size, native human teeth in mouse dorsum for the tested 3 weeks, delivery of basic fibroblast growth factor and/or vascular endothelial growth factor (bFGF and/or VEGF) yielded re-cellularized and revascularized connective tissue that integrated to native dentinal wall in root canals. Further, combined delivery of bFGF, VEGF, or platelet-derived growth factor (PDGF) with a basal set of nerve growth factor (NGF) and bone morphogenetic protein-7 (BMP7) generated cellularized and vascularized tissues positive of VEGF antibody staining and apparent neo-dentin formation over the surface of native dentinal wall in some, but not all, endodontically treated teeth. Newly formed dental pulp tissue appeared dense with disconnected cells surrounded by extracellular matrix. Erythrocyte-filled blood vessels were present with endothelial-like cell lining. Reconstructed, multiple microscopic images showed complete fill of dental-pulp-like tissue in the entire root canal from root apex to pulp chamber with tissue integration to dentinal wall upon delivery of bFGF, VEGF, or PDGF with a basal set of NGF and BMP7. Quantitative ELISA showed that combinatory delivery of bFGF, VEGF, or PDGF with basal NGF and BMP7 elaborated von Willerbrand factor, dentin sialoprotein, and NGF. These findings represent the first demonstration of regenerated dental-pulp-like tissue in endodontically treated root canals of real-size, native human teeth. The present chemotaxis-based approach has potent cell homing effects for re-cellularization and revascularization in endodontically treated root canals in vivo, although in an ectopic model

  10. Dental stem cells: recent progresses in tissue engineering and regenerative medicine.

    Science.gov (United States)

    Botelho, João; Cavacas, Maria Alzira; Machado, Vanessa; Mendes, José João

    2017-12-01

    Since the disclosure of adult mesenchymal stem cells (MSCs), there have been an intense investigation on the characteristics of these cells and their potentialities. Dental stem cells (DSCs) are MSC-like populations with self-renewal capacity and multidifferentiation potential. Currently, there are five main DSCs, dental pulp stem cells (DPSCs), stem cells from exfoliated deciduous teeth (SHED), stem cells from apical papilla (SCAP), periodontal ligament stem cells (PDLSCs) and dental follicle precursor cells (DFPCs). These cells are extremely accessible, prevail during all life and own an amazing multipotency. In the past decade, DPSCs and SHED have been thoroughly studied in regenerative medicine and tissue engineering as autologous stem cells therapies and have shown amazing therapeutic abilities in oro-facial, neurologic, corneal, cardiovascular, hepatic, diabetic, renal, muscular dystrophy and auto-immune conditions, in both animal and human models, and most recently some of them in human clinical trials. In this review, we focus the characteristics, the multiple roles of DSCs and its potential translation to clinical settings. These new insights of the apparently regenerative aptitude of these DSCs seems quite promising to investigate these cells abilities in a wide variety of pathologies. Key messages Dental stem cells (DSCs) have a remarkable self-renewal capacity and multidifferentiation potential; DSCs are extremely accessible and prevail during all life; DSCs, as stem cells therapies, have shown amazing therapeutic abilities in oro-facial, neurologic, corneal, cardiovascular, hepatic, diabetic, renal, muscular dystrophy and autoimmune conditions; DSCs are becoming extremely relevant in tissue engineering and regenerative medicine.

  11. The Neurovascular Properties of Dental Stem Cells and Their Importance in Dental Tissue Engineering

    OpenAIRE

    Ratajczak, Jessica; Bronckaers, Annelies; Dillen, Yörg; Gervois, Pascal; Vangansewinkel, Tim; Driesen, Ronald; Wolfs, Esther; Lambrichts, Ivo; Hilkens, Petra

    2016-01-01

    Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be dis...

  12. Functions of Periostin in dental tissues and its role in periodontal tissues' regeneration.

    Science.gov (United States)

    Du, Juan; Li, Minqi

    2017-12-01

    The goal of periodontal regenerative therapy is to predictably restore the tooth's supporting periodontal tissues and form a new connective tissue attachment of periodontal ligament (PDL) fibers and new alveolar bone. Periostin is a matricellular protein so named for its expression primarily in the periosteum and PDL of adult mice. Its biological functions have been widely studied in areas such as cardiovascular physiology and oncology. Despite being initially identified in the dental tissues and bone, investigations of Periostin functions in PDL and alveolar-bone-related physiopathology are less abundant. Recently, several studies have suggested that Periostin may be an important regulator of periodontal tissue formation. By promoting collagen fibrillogenesis and the migration of fibroblasts and osteoblasts, Periostin might play a pivotal part in regeneration of the PDL and alveolar bone following periodontal surgery. The aim of this article is to provide an extensive review of the implications of Periostin in periodontal tissue biology and its potential use in periodontal tissue regeneration.

  13. Aspartate aminotransferase activity in human healthy and inflamed dental pulps.

    Science.gov (United States)

    Spoto, G; Fioroni, M; Rubini, C; Tripodi, D; Perinetti, G; Piattelli, A

    2001-06-01

    Aspartate aminotransferase (AST) seems to be an important mediator of inflammatory processes. Its role in the progression and detection of inflammatory periodontal disease has been increasingly recognized in recent years. In the present study AST activity was analyzed in normal healthy human dental pulps, in reversible pulpitis, and in irreversible pulpitis. Enzymatic AST activity showed that the control values for the healthy pulps were 4.8 +/- 0.7 units/mg of pulp tissue. In reversible pulpitis specimens the AST activity increased to 7.98 +/- 2.1 units/mg of pulp tissue. In irreversible pulpitis specimens the values decreased to 2.28 +/- 1.7 units/mg of pulp tissue. Differences between the groups (control versus reversible pulpitis and reversible pulpitis versus irreversible pulpitis) were statistically significant (p = 0.0015). These results could point to a role of AST in the early events that lead to development of pulpal inflammation.

  14. General evaluation of hard dental tissue and risk factors of dental caries in young people

    Directory of Open Access Journals (Sweden)

    Антоніна Михайлівна Політун

    2016-04-01

    Full Text Available The prognostication of caries in youth is important for determination and prescription of individual prophylactic arrangements and its further influence on mineralization of the hard dental tissues.Aim of the work: the study of the prevalence and intensity of caries among the young people and determination of possible connection with the risk factor of caries development for further choice of the reasonable prophylactic arrangement.Materials and methods of research: epidemiological, clinical, statistic ones.Results of research: The article describes results of the comprehensive dental examination of 135 persons18-25 years old. There was determined the high prevalence of caries (96,3±0,74 % with considerable intensity (8,87±0,39. The main etiological factors among youth are: poor nutrition with prevalence of carbohydrate (74,81±0,56 %, lack of oral hygiene (59,27±0,73 %, quantitative and qualitative composition of oral fluid, presence of somatic diseases (40±0,30 %, bad habits (31,85±0,24 %, neglect of the sport (48,88±0,36 %, chronic emotional stress (38,51±0,29 %, due to the increased workload and related stress factors.Conclusions: the high prevalence (96,3±0,74 % and intensity of carious process (8,87±0,39 is caused by the unsatisfactory state of oral cavity, (1,91±0,06, under the influence of general factors (somatic diseases, stress, poor nutrition the reactivity of protective mechanisms is lowered and the risk of dental morbidity of youth increases. So, it proves the necessity of elaboration and introduction of the active arrangements of primary prophylaxis directed on the raise of caries resistance of the hard dental tissues in young people

  15. A tissue-dependent hypothesis of dental caries.

    Science.gov (United States)

    Simón-Soro, A; Belda-Ferre, P; Cabrera-Rubio, R; Alcaraz, L D; Mira, A

    2013-01-01

    Current understanding of dental caries considers this disease a demineralization of the tooth tissues due to the acid produced by sugar-fermenting microorganisms. Thus, caries is considered a diet- and pH-dependent process. We present here the first metagenomic analysis of the bacterial communities present at different stages of caries development, with the aim of determining whether the bacterial composition and biochemical profile are specific to the tissue affected. The data show that microbial composition at the initial, enamel-affecting stage of caries is significantly different from that found at subsequent stages, as well as from dental plaque of sound tooth surfaces. Although the relative proportion of Streptococcus mutans increased from 0.12% in dental plaque to 0.72% in enamel caries, Streptococcus mitis and Streptococcus sanguinis were the dominant streptococci in these lesions. The functional profile of caries-associated bacterial communities indicates that genes involved in acid stress tolerance and dietary sugar fermentation are overrepresented only at the initial stage (enamel caries), whereas other genes coding for osmotic stress tolerance as well as collagenases and other proteases enabling dentin degradation are significantly overrepresented in dentin cavities. The results support a scenario in which pH and diet are determinants of the disease during the degradation of enamel, but in dentin caries lesions not only acidogenic but also proteolytic bacteria are involved. We propose that caries disease is a process of varying etiology, in which acid-producing bacteria are the vehicle to penetrate enamel and allow dentin degrading microorganisms to expand the cavity. © 2013 S. Karger AG, Basel.

  16. Caries management pathways preserve dental tissues and promote oral health.

    Science.gov (United States)

    Ismail, Amid I; Tellez, Marisol; Pitts, Nigel B; Ekstrand, Kim R; Ricketts, David; Longbottom, Christopher; Eggertsson, Hafsteinn; Deery, Christopher; Fisher, Julian; Young, Douglas A; Featherstone, John D B; Evans, Wendell; Zeller, Gregory G; Zero, Domenick; Martignon, Stefania; Fontana, Margherita; Zandona, Andrea

    2013-02-01

    In May 2012, cariologists, dentists, representatives of dental organizations, manufacturers, and third party payers from several countries, met in Philadelphia, Pennsylvania, to define a common mission; goals and strategic approaches for caries management in the 21th century. The workshop started with an address by Mr. Stanley Bergman, CEO of Henry Schein Inc. which focused on the imperative for change in academia, clinical practice, and public health. For decades, new scientific evidence on caries and how it should be managed have been discussed among experts in the field. However, there has been some limited change, except in some Scandinavian countries, in the models of caries management and reimbursement which have been heavily skewed toward 'drilling and filling'. There is no overall agreement on a caries' case definition or on when to surgically intervene. The participants in the workshop defined a new mission for all caries management approaches, both conventional and new. The mission of each system should be to preserve the tooth structure, and restore only when necessary. This mission marks a pivotal line for judging when to surgically intervene and when to arrest or remineralize early noncavitated lesions. Even when restorative care is necessary, the removal of hard tissues should be lesion-focused and aim to preserve, as much as possible, sound tooth structure. Continuing management of the etiological factors of caries and the use of science-based preventive regimens also will be required to prevent recurrence and re-restoration. These changes have been debated for over a decade. The Caries Management Pathways includes all systems and philosophies, conventional and new, of caries management that can be used or modified to achieve the new mission. The choice of which system to use to achieve the mission of caries management is left to the users and should be based on the science supporting each approach or philosophy, experience, utility, and ease of use

  17. Efficacy of soft tissue augmentation around dental implants and in partially edentulous areas: a systematic review.

    Science.gov (United States)

    Thoma, Daniel S; Buranawat, Borvornwut; Hämmerle, Christoph H F; Held, Ulrike; Jung, Ronald E

    2014-04-01

    To review the dental literature in terms of efficacy of soft tissue augmentation procedures around dental implants and in partially edentulous sites. A Medline search was performed for human studies augmenting keratinized mucosa (KM) and soft tissue volume around implants and in partially edentulous areas. Due to heterogeneity in between the studies, no meta-analyses could be performed. Nine (KM) and eleven (volume) studies met the inclusion criteria. An apically positioned flap/vestibuloplasty (APF/V) plus a graft material [free gingival graft (FGG)/subepithelial connective tissue graft (SCTG)/collagen matrix (CM)] resulted in an increase of keratinized tissue (1.4-3.3 mm). Statistically significantly better outcomes were obtained for APF/V plus FGG/SCTG compared with controls (APF/V alone; no treatment) (p FGG/SCTG was the best-documented and most successful method to increase the width of KM. APF/V plus CM demonstrated less gain in KM, but also less patient morbidity and surgery time compared to APF/V plus SCTG based on two RCTs. Autogenous grafts (SCTG) rendered an increase in soft tissue thickness and better aesthetics compared to non-grafted sites. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. The form of the human dental arch.

    Science.gov (United States)

    Braun, S; Hnat, W P; Fender, D E; Legan, H L

    1998-02-01

    The human dental arch form is shown to be accurately represented mathematically by the beta function. The average correlation coefficient between measured arch-shape data and the mathematical arch shape, expressed by the beta function, is 0.98 with a standard deviation of 0.02. Forty sets of casts--15 Class I, 16 Class II, and 9 Class III--were examined. A precision machine tool device was used to record the X-, Y-, and Z-coordinates of selected dental landmarks on all casts to 0.001 mm accuracy. The coordinates were processed through a computer curve-fitting program. The Class III mandibular arches had smaller arch depth and greater arch width (beginning in the premolar area) than the Class I arches. The Class II mandibular arches exhibited generalized reduced arch width and depth compared with the Class I arches. Maxillary arch depths were similar in all three groups. However, the Class III maxillary arch widths were greater from the lateral incisor-canine area distally compared with the Class I maxillary arch, and the Class II maxillary arch form was narrower than the Class I arch form from the lateral incisor-canine area distally. The beta function more accurately described the dental arch form than representations previously reported.

  19. Property Of Human Dental Pulp Stem Cells And Peripheral Blood Hematopoietic Stem Cells That Differentiated Both Group To Cardiac Cells

    OpenAIRE

    Jabari F; Mohammadnejad J; Yavari K

    2013-01-01

    Dental pulp is the soft live tissue inside a tooth. Dental pulp contains stem cells, known as Dental Pulp Stem Cells. The finest Dental Pulp Stem Cells are found in a baby teeth or milk teeth. The stem cells from the milk teeth are ‘mesenchymal’ type of cells. cells that have the ability to generate a wide variety of cell types like chondrocytes, osteoblasts and adipocytes. To isolate high-quality human dental pulp stem cells from accessible resources is an important goal for stem-cell resear...

  20. Extracellular matrix of dental pulp stem cells: applications in pulp tissue engineering using somatic MSCs

    OpenAIRE

    Ravindran, Sriram; Huang, Chun-Chieh; George, Anne

    2014-01-01

    Dental Caries affects approximately 90% of the world’s population. At present, the clinical treatment for dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality. Tissue engineering can potentially solve this problem by enabling regeneration of a functional pulp tissue. Dental pulp stem cells (DPSCs) have been shown to be an excellent source for pulp regeneration. However, limited availability of these cells hinders its potential for clinica...

  1. Dimensional soft tissue changes following soft tissue grafting in conjunction with implant placement or around present dental implants: a systematic review.

    Science.gov (United States)

    Poskevicius, Lukas; Sidlauskas, Antanas; Galindo-Moreno, Pablo; Juodzbalys, Gintaras

    2017-01-01

    To systematically review changes in mucosal soft tissue thickness and keratinised mucosa width after soft tissue grafting around dental implants. An electronic literature search was conducted of the MEDLINE database published between 2009 and 2014. Sequential screenings at the title, abstract, and full-text levels were performed. Clinical human studies in the English language that had reported changes in soft tissue thickness or keratinised mucosa width after soft tissue grafting at implant placement or around a present implant at 6-month follow-up or longer were included. The search resulted in fourteen articles meeting the inclusion criteria: Six of them reported connective tissue grafting around present dental implants, compared to eight at the time of implant placement. Better long-term soft tissue thickness outcomes were reported for soft tissue augmentation around dental implants (0.8-1.4 mm), compared with augmentation at implant placement (-0.25-1.43 mm). Both techniques were effective in increasing keratinised tissue width: at implant placement (2.5 mm) or around present dental implants (2.33-2.57 mm). The present systematic review discovered that connective tissue grafts enhanced keratinised mucosa width and soft tissue thickness for an observation period of up to 48 months. However, some shrinkage may occur, resulting in decreases in soft tissue, mostly for the first three months. Further investigations using accurate evaluation methods need to be done to evaluate the appropriate time for grafting. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Ability of stem and progenitor cells in the dental pulp to form hard tissue

    Directory of Open Access Journals (Sweden)

    Akihiro Hosoya, DDS, PhD

    2015-08-01

    Full Text Available Dental pulp has an important ability to form mineralized hard tissue in response to a variety of external stimuli. The formation of mineralized tissue within the pulp cavity has been widely examined in both clinical and animal studies. Despite these studies focusing on the phenomena of reparative dentin and dentin bridge formation, the mechanisms of their induction remain unknown. Recently, several morphological studies revealed that the source of cells for hard tissue formation is the dental pulp itself, even after pulp injury. This finding indicates that the dental pulp tissue contains undifferentiated cells participating in dentin and pulp regeneration. Additionally, stem and progenitor cells isolated from the dental pulp were found to differentiate into odontoblasts as well as osteoblasts. This review presents current evidences for the multipotent ability of dental pulp cells and their usefulness in tissue engineering applications as a cell resource.

  3. Soft matrix supports osteogenic differentiation of human dental follicle cells

    Energy Technology Data Exchange (ETDEWEB)

    Viale-Bouroncle, Sandra; Voellner, Florian [Department of Operative Dentistry and Periodontology, University Hospital Regensburg, Regensburg (Germany); Moehl, Christoph; Kuepper, Kevin [Institute of Complex Systems, ICS7: Biomechanics, Forschungszentrum Juelich, Juelich (Germany); Brockhoff, Gero [Department of Gynecology and Obstetrics, University of Regensburg (Germany); Reichert, Torsten E. [Department of Oral and Maxillofacial Surgery, University Hospital Regensburg, Regensburg (Germany); Schmalz, Gottfried [Department of Operative Dentistry and Periodontology, University Hospital Regensburg, Regensburg (Germany); Morsczeck, Christian, E-mail: christian.morsczeck@klinik.uni-regensburg.de [Department of Operative Dentistry and Periodontology, University Hospital Regensburg, Regensburg (Germany)

    2011-07-08

    Highlights: {yields} Rigid stiffness supports osteogenic differentiation in mesenchymal stem cells (MSCs). {yields} Our study examined stiffness and differentiation of dental follicle cells (DFCs). {yields} Soft ECMs have a superior capacity to support the osteogenic differentiation of DFCs. {yields} DFCs and MSCs react contrarily to soft and rigid surface stiffness. -- Abstract: The differentiation of stem cells can be directed by the grade of stiffness of the developed tissue cells. For example a rigid extracellular matrix supports the osteogenic differentiation in bone marrow derived mesenchymal stem cells (MSCs). However, less is known about the relation of extracellular matrix stiffness and cell differentiation of ectomesenchymal dental precursor cells. Our study examined for the first time the influence of the surface stiffness on the proliferation and osteogenic differentiation of human dental follicle cells (DFCs). Cell proliferation of DFCs was only slightly decreased on cell culture surfaces with a bone-like stiffness. The osteogenic differentiation in DFCs could only be initiated with a dexamethasone based differentiation medium after using varying stiffness. Here, the softest surface improved the induction of osteogenic differentiation in comparison to that with the highest stiffness. In conclusion, different to bone marrow derived MSCs, soft ECMs have a superior capacity to support the osteogenic differentiation of DFCs.

  4. Direct spectrometry: a new alternative for measuring the fluorescence of composite resins and dental tissues.

    Science.gov (United States)

    da Silva, Tm; de Oliveira, Hpm; Severino, D; Balducci, I; Huhtala, Mfrl; Gonçalves, Sep

    2014-01-01

    The aim of this study was to evaluate the fluorescence intensity of different composite resins and compare those values with the fluorescence intensity of dental tissues. Different composite resins were used to make 10 discs (2 mm in depth and 4 mm in diameter) of each brand, divided into groups: 1) Z (Filtek Z350, 3M ESPE), 2) ES (Esthet-X, Dentsply), 3) A (Amelogen Plus, Ultradent), 4) DVS (Durafill-VS, Heraeus Kulzer) with 2 mm composite resin for enamel (A2), 5) OES ([Esthet-X] opaque-OA [1 mm] + enamel-A2 [1 mm]); 6) ODVSI ([Charisma-Opal/Durafill-VSI], opaque-OM (1 mm) + translucent [1mm]), and 7) DVSI ([Durafill- VSI] translucent [2 mm]). Dental tissue specimens were obtained from human anterior teeth cut in a mesiodistal direction to obtain enamel, dentin, and enamel/dentin samples (2 mm). The fluorescence intensity of specimens was directly measured using an optic fiber associated with a spectrometer (Ocean Optics USB 4000) and recorded in graphic form (Origin 8.0 program). Data were submitted to statistical analysis using Dunnet, Tukey, and Kruskall-Wallis tests. Light absorption of the composite resins was obtained in a spectral range from 250 to 450 nm, and that of dental tissues was between 250 and 300 nm. All composite resins were excited at 398 nm and exhibited maximum emissions of around 485 nm. Fluorescence intensity values for all of the resins showed statistically significant differences (measured in arbitrary units [AUs]), with the exception of groups Z and DVS. Group DVSI had the highest fluorescence intensity values (13539 AU), followed by ODVS (10440 AU), DVS (10146 AU), ES (3946 AU), OES (3841 AU), A (3540 AU), and Z (1146 AU). The fluorescence intensity values for the composite resins differed statistically from those of dental tissues (E=1380 AU; D=6262 AU; E/D=3251 AU). The opacity interfered with fluorescence intensity, and group Z demonstrated fluorescence intensity values closest to that of tooth enamel. It is concluded that the

  5. Multilineage potential and proteomic profiling of human dental stem cells derived from a single donor

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Rajreddy; Kumar, B. Mohana; Lee, Won-Jae; Jeon, Ryoung-Hoon; Jang, Si-Jung; Lee, Yeon-Mi [Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Park, Bong-Wook; Byun, June-Ho [Department of Oral and Maxillofacial Surgery, School of Medicine and Institute of Health Science, Gyeongsang National University, Jinju 660-702 (Korea, Republic of); Ahn, Chun-Seob; Kim, Jae-Won [Department of Microbiology, Division of Life Sciences, Research Institute of Life Science, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Rho, Gyu-Jin, E-mail: jinrho@gnu.ac.kr [Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Research Institute of Life Sciences, Gyeongsang National University, Jinju 660-701 (Korea, Republic of)

    2014-01-01

    Dental tissues provide an alternative autologous source of mesenchymal stem cells (MSCs) for regenerative medicine. In this study, we isolated human dental MSCs of follicle, pulp and papilla tissue from a single donor tooth after impacted third molar extraction by excluding the individual differences. We then compared the morphology, proliferation rate, expression of MSC-specific and pluripotency markers, and in vitro differentiation ability into osteoblasts, adipocytes, chondrocytes and functional hepatocyte-like cells (HLCs). Finally, we analyzed the protein expression profiles of undifferentiated dental MSCs using 2DE coupled with MALDI-TOF-MS. Three types of dental MSCs largely shared similar morphology, proliferation potential, expression of surface markers and pluripotent transcription factors, and differentiation ability into osteoblasts, adipocytes, and chondrocytes. Upon hepatogenic induction, all MSCs were transdifferentiated into functional HLCs, and acquired hepatocyte functions by showing their ability for glycogen storage and urea production. Based on the proteome profiling results, we identified nineteen proteins either found commonly or differentially expressed among the three types of dental MSCs. In conclusion, three kinds of dental MSCs from a single donor tooth possessed largely similar cellular properties and multilineage potential. Further, these dental MSCs had similar proteomic profiles, suggesting their interchangeable applications for basic research and call therapy. - Highlights: • Isolated and characterized three types of human dental MSCs from a single donor. • MSCs of dental follicle, pulp and papilla had largely similar biological properties. • All MSCs were capable of transdifferentiating into functional hepatocyte-like cells. • 2DE proteomics with MALDI-TOF/MS identified 19 proteins in three types of MSCs. • Similar proteomic profiles suggest interchangeable applications of dental MSCs.

  6. Exosomes as biomimetic tools for stem cell differentiation: Applications in dental pulp tissue regeneration.

    Science.gov (United States)

    Huang, Chun-Chieh; Narayanan, Raghuvaran; Alapati, Satish; Ravindran, Sriram

    2016-12-01

    Achieving and maintaining safe and reliable lineage specific differentiation of stem cells is important for clinical translation of tissue engineering strategies. In an effort to circumvent the multitude of problems arising from the usage of growth factors and growth factor delivery systems, we have explored the use of exosomes as biomimetic tools to induce stem cell differentiation. Working on the hypothesis that cell-type specific exosomes can trigger lineage-specific differentiation of stem cells, we have evaluated the potential of exosomes derived from dental pulp cells cultured on under growth and odontogenic differentiation conditions to induce odontogenic differentiation of naïve human dental pulp stem cells (DPSCs) and human bone marrow derived stromal cells (HMSCs) in vitro and in vivo. Results indicate that the exosomes can bind to matrix proteins such as type I collagen and fibronectin enabling them to be tethered to biomaterials. The exosomes are endocytosed by both DPSCs and HMSCs in a dose-dependent and saturable manner via the caveolar endocytic mechanism and trigger the P38 mitogen activated protein kinase (MAPK) pathway. In addition, the exosomes also trigger the increased expression of genes required for odontogenic differentiation. When tested in vivo in a tooth root slice model with DPSCs, the exosomes triggered regeneration of dental pulp-like tissue. However, our results indicate that exosomes isolated under odontogenic conditions are better inducers of stem cell differentiation and tissue regeneration. Overall, our results highlight the potential exosomes as biomimetic tools to induce lineage specific differentiation of stem cells. Our results also show the importance of considering the source and state of exosome donor cells before a choice is made for therapeutic applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. The sound of dental tissue ablation as a possible parameter for conservative dentistry

    Science.gov (United States)

    Robles, Fábio Renato P.; Mendes, Fausto Medeiros; Matos, Adriana Bona

    2007-02-01

    Studies in cariology have been struggling for the development of caries prevention techniques, precocious diagnoses of lesions, re-mineralization of incipient carious lesions and early restorative intervention with minimally invasive procedures. When removing caries, healthy dental structure is often removed inadvertently during its final phase, for being quite difficult to precise the limits between viable and decayed dental tissues clinically. With laser technologies, a subjective clinical hint, often used to indicate when tissue ablation should be stopped is that different sounds are perceptive whether in carious (bass) or in healthy (treble) dental structure; when sound produced by ablation turned treble it would mean that healthy tissue was reached. This study aims to classify those audio differences and to turn them into objective parameters for a conservative operative dentistry with minimally invasive tissue removal when using erbium lasers. Twenty freshly extracted human teeth were used (10 decayed and 10 sound teeth). Dentine was erbium laser irradiated under same parameters, distance and refrigeration and a mono directional microphone was set 10 cm far from the operative area in order to capture and record the ablation produced sounds when working either on carious or healthy dentine. Ten pulses per file were then analysed in a computer software (200 analyses). It was permitted to draw similarities among the patterns in each group (decayed and healthy teeth) as well as differences between decayed and healthy produced sounds. Audio analysis came out to be a technical reliable objective parameter to determine whether laser ablated dentine substrates are decayed or sound; therefore it can be proposed as a conservative parameter, avoiding unnecessary removal of healthy dentine and restricting it to carious one.

  8. 3D Bioprinting of Vascularized Human Tissues

    OpenAIRE

    Kolesky, David Barry

    2016-01-01

    The ability to manufacture human tissues that replicate the spatial, mechano-chemical, and temporal aspects of biological tissues would enable myriad applications, including drug screening, disease modeling, and tissue repair and regeneration. However, given the complexity of human tissues, this is a daunting challenge. Current biofabrication methods are unable to fully recapitulate the form and function of human tissues, which are composed of multiple cell types, extracellular matrices, and ...

  9. Decellularized Human Dental Pulp as a Scaffold for Regenerative Endodontics.

    Science.gov (United States)

    Song, J S; Takimoto, K; Jeon, M; Vadakekalam, J; Ruparel, N B; Diogenes, A

    2017-06-01

    Teeth undergo postnatal organogenesis relatively late in life and only complete full maturation a few years after the crown first erupts in the oral cavity. At this stage, development can be arrested if the tooth organ is damaged by either trauma or caries. Regenerative endodontic procedures (REPs) are a treatment alternative to conventional root canal treatment for immature teeth. These procedures rely on the transfer of apically positioned stem cells, including stem cells of the apical papilla (SCAP), into the root canal system. Although clinical success has been reported for these procedures, the predictability of expected outcomes and the organization of the newly formed tissues are affected by the lack of an available suitable scaffold that mimics the complexity of the dental pulp extracellular matrix (ECM). In this study, we evaluated 3 methods of decellularization of human dental pulp to be used as a potential autograft scaffold. Tooth slices of human healthy extracted third molars were decellularized by 3 different methods. One of the methods generated the maximum observed decellularization with minimal impact on the ECM composition and organization. Furthermore, recellularization of the scaffold supported the proliferation of SCAP throughout the scaffold with differentiation into odontoblast-like cells near the dentinal walls. Thus, this study reports that human dental pulp from healthy extracted teeth can be successfully decellularized, and the resulting scaffold supports the proliferation and differentiation of SCAP. The future application of this form of an autograft in REPs can fulfill a yet unmet need for a suitable scaffold, potentially improving clinical outcomes and ultimately promoting the survival and function of teeth with otherwise poor prognosis.

  10. Nigerian Dental Technology Students and Human ...

    African Journals Online (AJOL)

    sectional study of dental technology students of Federal School of Dental Therapy and Technology. Enugu, Nigeria was conducted in 2010. Data was subjected to descriptive, non‑parametric and parametric statistics using the statistical package ...

  11. Fluorescence properties of human teeth and dental calculus for clinical applications.

    Science.gov (United States)

    Lee, Yong-Keun

    2015-04-01

    Fluorescent emission of human teeth and dental calculus is important for the esthetic rehabilitation of teeth, diagnosis of dental caries, and detection of dental calculus. The purposes of this review were to summarize the fluorescence and phosphorescence of human teeth by ambient ultraviolet (UV) light, to investigate the clinically relevant fluorescence measurement methods in dentistry, and to review the fluorescence of teeth and dental calculus by specific wavelength light. Dentine was three times more phosphorescent than enamel. When exposed to light sources containing UV components, the fluorescence of human teeth gives them the quality of vitality, and fluorescent emission with a peak of 440 nm is observed. Esthetic restorative materials should have fluorescence properties similar to those of natural teeth. Based on the fluorescence of teeth and restorative materials as determined with a spectrophotometer, a fluorescence parameter was defined. As to the fluorescence spectra by a specific wavelength, varied wavelengths were investigated for clinical applications, and several methods for the diagnosis of dental caries and the detection of dental calculus were developed. Since fluorescent properties of dental hard tissues have been used and would be expanded in diverse fields of clinical practice, these properties should be investigated further, embracing newly developed optical techniques.

  12. Regeneration Approaches for Dental Pulp and Periapical Tissues with Growth Factors, Biomaterials, and Laser Irradiation

    Directory of Open Access Journals (Sweden)

    Shizu Hirata

    2011-10-01

    Full Text Available In current dental practice, restorative and endodontic procedures have been developed in an attempt to preserve the vitality of dental pulp after exposure to external stimuli such as caries infection. When damage to dental pulp is reversible, pulp wound healing can proceed, whereas irreversible damage induces pathological changes in dental pulp, eventually requiring its removal. Furthermore, dentists sometimes extract non-vital teeth because of severe caries progression, critical size of periapical lesion, and tooth fracture. To overcome the limitations of presently available therapies, it is important to develop regeneration therapy for dental pulp and periapical tissues. In this review, we focus on the regeneration of dental pulp and periapical tissues by application of exogenous growth factors and scaffolds, as well as low-intensity laser irradiation as an auxiliary therapy for regeneration therapy.

  13. Dental orthopantomogram biometrics system for human identification.

    Science.gov (United States)

    Singh, Sandeep; Bhargava, Darpan; Deshpande, Ashwini

    2013-07-01

    Fingerprinting is the most widely accepted method of identification of people. But in cases of disfigured, decomposed, burnt or fragmented bodies, it is of limited value. Teeth and dental restorations on the other hand are extremely resistant to destruction by fire. They retain a number of their original characteristics, which are often unique and hence offer a possibility of rather accurate and legally acceptable identification of such remains. This study was undertaken to evaluate the utility of orthopantomography for human identification and propose a coding system for orthopantomogram (OPG), which can be utilized as an identification tool in forensic sciences. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  14. Laser equipment for investigation of light distribution in dental tissues and restorative materials

    Science.gov (United States)

    Grisimov, Vladimir N.; Smirmov, Alexander V.; Stafeev, Sergey C.

    1997-04-01

    The description of experimental set-up for investigation of light scattering in dental tissue and dental restorative material is presented. The set-up includes the light source (He-Ne laser), beam shaping light polarization control unit and registration device. The latter represents the computer interfaced CCD-camera. The experimental results of side light scattering in enamel/dentin and in double-layer porcelain are represented. The results of this research may be useful for aesthetic dental restorations.

  15. Comparative In Vitro Evaluation of Human Dental Pulp and Follicle Stem Cell Commitment.

    Science.gov (United States)

    Karamzadeh, Razieh; Baghaban Eslaminejad, Mohamadreza; Sharifi-Zarchi, Ali

    2017-01-01

    Pulp and periodontal tissues are well-known sources of mesenchymal stem cells (MSCs) that provide a promising place in tissue engineering and regenerative medicine. The molecular mechanisms underlying commitment and differentiation of dental stem cells that originate from different dental tissues are not fully understood. In this study, we have compared the expression levels of pluripotency factors along with immunological and developmentally-related markers in the culture of human dental pulp stem cells (hDPSCs), human dental follicle stem cells (hDFSCs), and human embryonic stem cells (hESCs). In this experimental study, isolated human dental stem cells were investigated using quantitative polymerase chain reaction (qPCR), immunostaining, and fluorescence-activated cell sorting (FACS). Additionally, we conducted gene ontology (GO) analysis of differentially expressed genes and compared them between dental stem cells and pluripotent stem cells. The results demonstrated that pluripotency (OCT4 and SOX2) and immunological (IL-6 and TLR4) factors had higher expressions in hDFSCs, with the exception of the JAGGED-1/NOTCH1 ratio, c-MYC and NESTIN which expressed more in hDPSCs. Immunostaining of OCT4, SOX2 and c-MYC showed cytoplasmic and nucleus localization in both groups at similar passages. GO analysis showed that the majority of hDFSCs and hDPSCs populations were in the synthesis (S) and mitosis (M) phases of the cell cycle, respectively. This study showed different status of heterogeneous hDPSCs and hDFSCs in terms of stemness, differentiation fate, and cell cycle phases. Therefore, the different behaviors of dental stem cells should be considered based on clinical treatment variations.

  16. Characteristics of the number of odontoblasts in human dental pulp post-mortem.

    Science.gov (United States)

    Vavpotic, Marko; Turk, Tomaz; Martincic, Draga Stiblar; Balazic, Joze

    2009-12-15

    Estimation of the time since death is important in forensic medicine, and so far not much is known in employing dental pulp for such purposes. The tooth organ is the hardest organ in the human body, with a loose connective tissue of dental pulp situated within a rigid encasement of mineralized surrounding tissues. Human material was obtained from 31 corpses of people who died in car and train accidents and had healthy oral statuses. Samples were divided into two groups at different environmental temperatures. During the autopsy, the jaws were resected to keep teeth in situ, and every day one tooth was extracted. After decalcification, serial thin sections stained with hematoxylin and eosin were cut. Odontoblasts in the dental pulp were counted and data analysed. Statistical analysis showed that the number of odontoblasts drops during the time after death, and no odontoblasts remain in the pulp after 5 days.

  17. Successful enrichment and recovery of whole mitochondrial genomes from ancient human dental calculus.

    Science.gov (United States)

    Ozga, Andrew T; Nieves-Colón, Maria A; Honap, Tanvi P; Sankaranarayanan, Krithivasan; Hofman, Courtney A; Milner, George R; Lewis, Cecil M; Stone, Anne C; Warinner, Christina

    2016-06-01

    Archaeological dental calculus is a rich source of host-associated biomolecules. Importantly, however, dental calculus is more accurately described as a calcified microbial biofilm than a host tissue. As such, concerns regarding destructive analysis of human remains may not apply as strongly to dental calculus, opening the possibility of obtaining human health and ancestry information from dental calculus in cases where destructive analysis of conventional skeletal remains is not permitted. Here we investigate the preservation of human mitochondrial DNA (mtDNA) in archaeological dental calculus and its potential for full mitochondrial genome (mitogenome) reconstruction in maternal lineage ancestry analysis. Extracted DNA from six individuals at the 700-year-old Norris Farms #36 cemetery in Illinois was enriched for mtDNA using in-solution capture techniques, followed by Illumina high-throughput sequencing. Full mitogenomes (7-34×) were successfully reconstructed from dental calculus for all six individuals, including three individuals who had previously tested negative for DNA preservation in bone using conventional PCR techniques. Mitochondrial haplogroup assignments were consistent with previously published findings, and additional comparative analysis of paired dental calculus and dentine from two individuals yielded equivalent haplotype results. All dental calculus samples exhibited damage patterns consistent with ancient DNA, and mitochondrial sequences were estimated to be 92-100% endogenous. DNA polymerase choice was found to impact error rates in downstream sequence analysis, but these effects can be mitigated by greater sequencing depth. Dental calculus is a viable alternative source of human DNA that can be used to reconstruct full mitogenomes from archaeological remains. Am J Phys Anthropol 160:220-228, 2016. © 2016 The Authors American Journal of Physical Anthropology Published by Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. Successful enrichment and recovery of whole mitochondrial genomes from ancient human dental calculus

    Science.gov (United States)

    Ozga, Andrew T.; Nieves‐Colón, Maria A.; Honap, Tanvi P.; Sankaranarayanan, Krithivasan; Hofman, Courtney A.; Milner, George R.; Lewis, Cecil M.; Stone, Anne C.

    2016-01-01

    ABSTRACT Objectives Archaeological dental calculus is a rich source of host‐associated biomolecules. Importantly, however, dental calculus is more accurately described as a calcified microbial biofilm than a host tissue. As such, concerns regarding destructive analysis of human remains may not apply as strongly to dental calculus, opening the possibility of obtaining human health and ancestry information from dental calculus in cases where destructive analysis of conventional skeletal remains is not permitted. Here we investigate the preservation of human mitochondrial DNA (mtDNA) in archaeological dental calculus and its potential for full mitochondrial genome (mitogenome) reconstruction in maternal lineage ancestry analysis. Materials and Methods Extracted DNA from six individuals at the 700‐year‐old Norris Farms #36 cemetery in Illinois was enriched for mtDNA using in‐solution capture techniques, followed by Illumina high‐throughput sequencing. Results Full mitogenomes (7–34×) were successfully reconstructed from dental calculus for all six individuals, including three individuals who had previously tested negative for DNA preservation in bone using conventional PCR techniques. Mitochondrial haplogroup assignments were consistent with previously published findings, and additional comparative analysis of paired dental calculus and dentine from two individuals yielded equivalent haplotype results. All dental calculus samples exhibited damage patterns consistent with ancient DNA, and mitochondrial sequences were estimated to be 92–100% endogenous. DNA polymerase choice was found to impact error rates in downstream sequence analysis, but these effects can be mitigated by greater sequencing depth. Discussion Dental calculus is a viable alternative source of human DNA that can be used to reconstruct full mitogenomes from archaeological remains. Am J Phys Anthropol 160:220–228, 2016. © 2016 The Authors American Journal of Physical Anthropology

  19. Distinctive genetic activity pattern of the human dental pulp between deciduous and permanent teeth.

    Directory of Open Access Journals (Sweden)

    Ji-Hee Kim

    Full Text Available Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11-14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR. Other teeth were used for immunohistochemical analysis (IHC. Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1 was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1, leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5, and gamma-aminobutyric acid A receptor beta 1 (GABRB1 were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration.

  20. Distinctive Genetic Activity Pattern of the Human Dental Pulp between Deciduous and Permanent Teeth

    Science.gov (United States)

    Kim, Ji-Hee; Jeon, Mijeong; Song, Je-Seon; Lee, Jae-Ho; Choi, Byung-Jai; Jung, Han-Sung; Moon, Seok Jun; DenBesten, Pamela K.; Kim, Seong-Oh

    2014-01-01

    Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11–14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR). Other teeth were used for immunohistochemical analysis (IHC). Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1), leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), and gamma-aminobutyric acid A receptor beta 1 (GABRB1) were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration. PMID:25047033

  1. Biomimetic extracellular matrix mediated somatic stem cell differentiation: applications in dental pulp tissue regeneration

    Science.gov (United States)

    Ravindran, Sriram; George, Anne

    2015-01-01

    Dental caries is one of the most widely prevalent infectious diseases in the world. It affects more than half of the world's population. The current treatment for necrotic dental pulp tissue arising from dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality making it prone for secondary infections. Over the past decade, several tissue-engineering approaches have attempted regeneration of the dental pulp tissue. Although several studies have highlighted the potential of dental stem cells, none have transitioned into a clinical setting owing to limited availability of dental stem cells and the need for growth factor delivery systems. Our strategy is to utilize the intact ECM of pulp cells to drive lineage specific differentiation of bone marrow derived mesenchymal stem cells. From a clinical perspective, pulp ECM scaffolds can be generated using cell lines and patient specific somatic stem cells can be used for regeneration. Our published results have shown the feasibility of using pulp ECM scaffolds for odontogenic differentiation of non-dental mesenchymal cells. This focused review discusses the issues surrounding dental pulp tissue regeneration and the potential of our strategy to overcome these issues. PMID:25954205

  2. Microstructure of mineralized tissues in human primary teeth.

    Science.gov (United States)

    Ruschel, H C; Ligocki, G D; Flaminghi, D L; Fossati, A C M

    2011-01-01

    The aim of this study was to analyze the structural characteristics of the mineralized dental tissues--enamel, dentin and cementum--in primary teeth and to correlate the histological aspects observed in function of the dental type--single-rooted or multi-rooted. Eighteen human primary noncarious teeth were sectioned in facial-lingual (single-rooted) and mesio-distal direction (multi-rooted). One to three samples from each tooth were obtained. The samples were prepared by the ground technique and analyzed under light microscopy at different magnifications. A quantitative and descriptive analysis of the morphology of the mineralized tissues was performed. Spindles, tufts and lamellae were consistently observed mainly in the occlusal surface of the primary molars. The scalloped pattern of the dentinoenamel junction was not always present. The same was seen for zones of interglobular dentin. Dead tracts in dentin and tertiary dentin were observed mainly in single-rooted teeth below areas of dental attrition. Areas of cellular and acellular cementum were observed in the two dental types. Primary teeth have some structural peculiarities and these should be investigated concerning the clinical repercussion.

  3. Nemotic human dental pulp fibroblasts promote human dental pulp stem cells migration.

    Science.gov (United States)

    Zhai, Shafei; Wang, Yafei; Jiang, Wenkai; Jia, Qian; Li, Jie; Wang, Wei; Wang, Haijing; Ding, Yonglin; Wang, Ping; Liu, Jun; Ni, Longxing

    2013-06-10

    Dental pulp inflammation has long been perceived as a negative factor leading to pulp disruption. Previous studies have suggested that the inflammatory reaction might be a prerequisite for the burst of progenitors implicated in pulp repair. To investigate the migration of human dental pulp stem cells (hDPSCs) in response to human dental pulp fibroblasts (HDPFs) nemosis, an in vitro model of nemosis-induced inflammation in three-dimensional culture was used in this study. We observed HDPF spheroid formation and that cell-cell adhesion between HDPFs leads to necrosis. Cell death detection and cell counting kit-8 assays showed reduced live cell numbers and increased levels of cell membrane leakage in HDPF spheroids. HDPFs spheroids expressed cyclooxygenase-2 and released an increasing amount of prostaglandin E2 and interleukin-8, indicating inflammation in response to nemosis. The Transwell assays showed that the conditioned medium from HDPFs spheroids significantly induced hDPSCs migration more than the medium from the monolayer. Taken together, these results indicate that HDPFs spheroids induce nemosis and contribute to the migration of hDPSCs. This model might provide a potential research tool for studying interactions between fibroblasts and stem cells, and studies concerning nemosis-targeted stem cells might help treat pulp inflammation. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Human tissue in systems medicine.

    Science.gov (United States)

    Caie, Peter D; Schuur, Klaas; Oniscu, Anca; Mullen, Peter; Reynolds, Paul A; Harrison, David J

    2013-12-01

    Histopathology, the examination of an architecturally artefactual, two-dimensional and static image remains a potent tool allowing diagnosis and empirical expectation of prognosis. Considerable optimism exists that the advent of molecular genetic testing and other biomarker strategies will improve or even replace this ancient technology. A number of biomarkers already add considerable value for prediction of whether a treatment will work. In this short review we argue that a systems medicine approach to pathology will not seek to replace traditional pathology, but rather augment it. Systems approaches need to incorporate quantitative morphological, protein, mRNA and DNA data. A significant challenge for clinical implementation of systems pathology is how to optimize information available from tissue, which is frequently sub-optimal in quality and amount, and yet generate useful predictive models that work. The transition of histopathology to systems pathophysiology and the use of multiscale data sets usher in a new era in diagnosis, prognosis and prediction based on the analysis of human tissue. © 2013 The Authors. FEBS Journal published by John Wiley & Sons Ltd on behalf of FEBS.

  5. Characterisation of dental pulp stem cells: a new horizon for tissue regeneration?

    Science.gov (United States)

    Kawashima, Nobuyuki

    2012-11-01

    Stem cells possess multipotent properties that allow them to differentiate into various cells, which may be potentially useful in tissue regeneration. Stem cell populations are reported to be present in various tissues of hematopoietic, neural and mesenchymal lineages, with the presence of stem cell populations in dental pulp tissue first described more than 10 years ago. The main components of dental pulp tissue are dental pulp cells, which are mesenchymal cells derived from the neural crest.(1,2) Some of these cells demonstrate high growth potential and possess multiple differentiation properties, and have been designated dental pulp stem cells (DPSCs). These cell populations are present not only in adult pulp tissue, but also in deciduous tooth pulp and apical papilla. DPSCs isolated by different methods, such as high growth potential, using various surface markers, and high efflux of a fluorescent nuclear stain (Hoechst 33342), all show multipotency, however their surface marker expression is somewhat different from each other. In vivo studies have revealed the possibility use of DPSCs in the regeneration of various tissue. DPSCs are of dental pulp origin, and dental pulp tissue is regenerated from DPSCs. Many researchers have focused on the dentine- and bone-forming properties of DPSCs, but their neuronal and muscular differentiation capacity suggests they may have a wider clinical application. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Analysis of titanium and other metals in human jawbones with dental implants - A case series study.

    Science.gov (United States)

    He, Xiuli; Reichl, Franz-Xaver; Wang, Yan; Michalke, Bernhard; Milz, Stefan; Yang, Yang; Stolper, Philipp; Lindemaier, Gabriele; Graw, Matthias; Hickel, Reinhard; Högg, Christof

    2016-08-01

    The aim of this study was to measure titanium (Ti) content in human jawbones and to show that Ti was released from dental implants inserted into these jawbones. Seven samples from four human subjects with dental implants were analysed as test group and six bone samples of similar topographical regions from six human subjects without implants served as control. The contents of various elements in human jawbones were detected by inductively coupled plasma optical emission spectrometry. The distributions of various isotopes in human mandibular bone were measured with laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Histological analyses of undecalcified, Giemsa-Eosin stained mandible sections were performed by light microscopy and particles were identified in human bone marrow by scanning electron microscope-energy dispersive X-ray analysis. In test group only Ti content was significantly higher compared to control group. The mean contents of Ti were 1940μg/kg in test group and 634μg/kg in control group. The highest Ti content detected in human mandibular bone was 37,700μg/kg-bone weight. In samples 4-7 (human subjects II-IV), increased Ti intensity was also detected by LA-ICP-MS in human mandibular tissues at a distance of 556-1587μm from implants, and the intensity increased with decreasing distance from implants. Particles with sizes of 0.5-40μm were found in human jawbone marrow tissues at distances of 60-700μm from implants in samples 4-7. Ti released from dental implants can be detected in human mandibular bone and bone marrow tissues, and the distribution of Ti in human bone was related to the distance to the implant. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  7. Forensic considerations when dealing with incinerated human dental remains.

    Science.gov (United States)

    Reesu, Gowri Vijay; Augustine, Jeyaseelan; Urs, Aadithya B

    2015-01-01

    Establishing the human dental identification process relies upon sufficient post-mortem data being recovered to allow for a meaningful comparison with ante-mortem records of the deceased person. Teeth are the most indestructible components of the human body and are structurally unique in their composition. They possess the highest resistance to most environmental effects like fire, desiccation, decomposition and prolonged immersion. In most natural as well as man-made disasters, teeth may provide the only means of positive identification of an otherwise unrecognizable body. It is imperative that dental evidence should not be destroyed through erroneous handling until appropriate radiographs, photographs, or impressions can be fabricated. Proper methods of physical stabilization of incinerated human dental remains should be followed. The maintenance of integrity of extremely fragile structures is crucial to the successful confirmation of identity. In such situations, the forensic dentist must stabilise these teeth before the fragile remains are transported to the mortuary to ensure preservation of possibly vital identification evidence. Thus, while dealing with any incinerated dental remains, a systematic approach must be followed through each stage of evaluation of incinerated dental remains to prevent the loss of potential dental evidence. This paper presents a composite review of various studies on incinerated human dental remains and discusses their impact on the process of human identification and suggests a step by step approach. Copyright © 2014 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  8. Nanofibrous spongy microspheres for the delivery of hypoxia-primed human dental pulp stem cells to regenerate vascularized dental pulp.

    Science.gov (United States)

    Kuang, Rong; Zhang, Zhanpeng; Jin, Xiaobing; Hu, Jiang; Shi, Songtao; Ni, Longxing; Ma, Peter X

    2016-03-01

    Dental pulp infection and necrosis are widespread diseases. Conventional endodontic treatments result in a devitalized and weakened tooth. In this work, we synthesized novel star-shaped polymer to self-assemble into unique nanofibrous spongy microspheres (NF-SMS), which were used to carry human dental pulp stem cells (hDPSCs) into the pulp cavity to regenerate living dental pulp tissues. It was found that NF-SMS significantly enhanced hDPSCs attachment, proliferation, odontogenic differentiation and angiogenesis, as compared to control cell carriers. Additionally, NF-SMS promoted vascular endothelial growth factor (VEGF) expression of hDPSCs in a 3D hypoxic culture. Hypoxia-primed hDPSCs/NF-SMS complexes were injected into the cleaned pulp cavities of rabbit molars for subcutaneous implantation in mice. After 4 weeks, the hypoxia group significantly enhanced angiogenesis inside the pulp chamber and promoted the formation of ondontoblast-like cells lining along the dentin-pulp interface, as compared to the control groups (hDPSCs alone group, NF-SMS alone group, and hDPSCs/NF-SMS group pre-cultured under normoxic conditions). Furthermore, in an in situ dental pulp repair model in rats, hypoxia-primed hDPSCs/NF-SMS were injected to fully fill the pulp cavity and regenerate pulp-like tissues with a rich vasculature and a histological structure similar to the native pulp. Vascularization is key to the regeneration of many vital tissues. However, it is challenging to create a suitable microenvironment for stem cells to regenerate vascularized tissue structure. This manuscript reports a novel star-shaped block copolymer that self-assembles into unique nanofibrous spongy microspheres, which as an injectable scaffold recapitulate the cell-cell and cell-matrix interactions in development. Using a clinically-relevant surgical procedure and a hypoxic treatment, the nanofibrous spongy microspheres were used to deliver stem cells and successfully regenerate dental pulp with a

  9. Dental Pulp Stem Cell Recruitment Signals within Injured Dental Pulp Tissue

    Directory of Open Access Journals (Sweden)

    Charlotte Rombouts

    2016-03-01

    Full Text Available The recruitment of dental pulp stem cells (DPSC is a prerequisite for the regeneration of dentin damaged by severe caries and/or mechanical injury. Understanding the complex process of DPSC recruitment will benefit future in situ tissue engineering applications based on the stimulation of endogenous DPSC for dentin pulp regeneration. The current known mobilization signals and subsequent migration of DPSC towards the lesion site, which is influenced by the pulp inflammatory state and the application of pulp capping materials, are reviewed. The research outcome of migration studies may be affected by the applied methodology, which should thus be chosen with care. Both the advantages and disadvantages of commonly used assays for investigating DPSC migration are discussed. This review highlights the fact that DPSC recruitment is dependent not only on the soluble chemotactic signals, but also on their interaction with neighboring cells and the extracellular matrix, which can be modified under pathological conditions. These are discussed to explain how these modifications lead to the stimulation of DPSC recruitment.

  10. Microbiota of human breast tissue

    National Research Council Canada - National Science Library

    Urbaniak, Camilla; Cummins, Joanne; Brackstone, Muriel; Macklaim, Jean M; Gloor, Gregory B; Baban, Chwanrow K; Scott, Leslie; O'Hanlon, Deidre M; Burton, Jeremy P; Francis, Kevin P; Tangney, Mark; Reid, Gregor

    2014-01-01

    .... We decided to investigate whether there is a microbiome within the mammary tissue. Using 16S rRNA sequencing and culture, we analyzed breast tissue from 81 women with and without cancer in Canada and Ireland...

  11. Heterodyne lock-in thermography of early demineralized in dental tissues

    Science.gov (United States)

    Wang, Fei; Liu, Jun-yan; Mohummad, Oliullah; Wang, Xiao-chun; Wang, Yang

    2017-12-01

    Heterodyne lock-in thermography (HeLIT) is a highly sensitive method to detect early demineralized in dental tissues, which is based on nonlinear photothermal phenomena of dental tissues. In this paper, the nonlinear photothermal phenomena of dental tissues was introduced, and then the system of HeLIT was developed. The relationship between laser modulated parameters (modulated frequency and laser intensity) and heterodyne lock-in thermal wave signal was investigated. The comparison between HeLIT and homodyne lock-in thermography (HoLIT) for detecting the different types of dental caries (smooth surface caries, proximal surface caries and occlusal surface caries) were carried out. Experimental results illustrate that the HeLIT has the merits of high sensitivity and high specificity in detecting different types of early caries.

  12. Comparison of odontogenic differentiation of human dental follicle cells and human dental papilla cells.

    Directory of Open Access Journals (Sweden)

    Lijuan Guo

    Full Text Available Classical tooth development theory suggests that dental papilla cells (DPCs are the precursor cells of odontoblasts, which are responsible for dentin development. However, our previous studies have indicated that dental follicle cells (DFCs can differentiate into odontoblasts. To further our understanding of tooth development, and the differences in dentinogenesis between DFCs and DPCs, the odontogenic differentiation of DFCs and DPCs was characterized in vitro and in vivo. DFCs and DPCs were individually combined with treated dentin matrix (TDM before they were subcutaneously implanted into the dorsum of mice for 8 weeks. Results showed that 12 proteins were significantly differential, and phosphoserine aminotransferase 1 (PSAT1, Isoform 2 of hypoxia-inducible factor 1-alpha (HIF1A and Isoform 1 of annexin A2 (ANXA2, were the most significantly differential proteins. These proteins are related to regulation of bone balance, angiogenesis and cell survival in an anoxic environment. Both DFCs and DPCs express odontogenic, neurogenic and peridontogenic markers. Histological examination of the harvested grafts showed that both DFCs and DPCs form pulp-dentin/cementum-periodentium-like tissues in vivo. Hence, DFCs and DPCs have similar odontogenic differentiation potential in the presence of TDM. However, differences in glucose and amino acid metabolism signal transduction and protein synthesis were observed for the two cell types. This study expands our understanding on tooth development, and provides direct evidence for the use of alternative cell sources in tooth regeneration.

  13. DENTAL STEM CELL SOURCES AND THEIR POTENTIALS FOR BONE TISSUE ENGINEERING

    Directory of Open Access Journals (Sweden)

    Fatih ASUTAY

    2015-04-01

    Full Text Available Tissue engineering arouses excitement in all medical fields that deal with bone healing. The ultimate aim of these approaches are to shorten the healing process, obtain highly differentiated functional tissues and eliminate the need for a second surgical site required for autogenous bone grafts. Mesenchymal stem cells have been increasingly used in the experiments which were conducted in these fields and the results are promising. Dental stem cells have come to the forefront both because of their relative ease of access and also their superior characteristics. This article investigates the importance of dental stem cells for bone tissue engineering and their regeneration potentials.

  14. Dental pulp tissue engineering of pulpotomized rat molars with bone marrow mesenchymal stem cells.

    Science.gov (United States)

    Ito, Takafumi; Kaneko, Tomoatsu; Sueyama, Yukiko; Kaneko, Reika; Okiji, Takashi

    2017-10-01

    The major goal of dental pulp tissue engineering is to enable the healing of inflamed tissue or to replace necrotic pulp tissue with newly formed dental pulp tissue. Here, we report a protocol for pulp tissue engineering in vivo in pulpotomized rat teeth using constructs of rat bone marrow mesenchymal stem cells, preformed biodegradable scaffolds, and hydrogel. The constructs were implanted into pulpotomized pulp chambers for 3, 7, or 14 days. At 3 days, cells were located mainly along the preformed scaffolds. At 7 days, pulp tissue regeneration was observed in almost the entire implanted region. At 14 days, pulp tissue regeneration further progressed throughout the implanted region. In immunohistochemistry, at 3 days, a number of small and round macrophages immunoreactive to CD68 were predominantly distributed around the scaffolds. The density of CD68+ macrophages decreased until 14 days. On the other hand, nestin-expressing odontoblast-like cells beneath the dentin at the border of implanted region increased until 14 days. Quantitative gene expression analysis revealed that odontoblast differentiation marker dentin sialophosphoprotein mRNA in the implanted region gradually increased until 14 days. Together, the results suggested that regeneration of dental pulp tissue had occurred. Thus, our study provides a novel experimental rat model of dental pulp regeneration.

  15. Soft tissue integration versus early biofilm formation on different dental implant materials

    NARCIS (Netherlands)

    Zhao, Bingran; van der Mei, Henderina; Subbiahdoss, Guruprakash; de Vries, Joop; Rustema-Abbing, Minie; Kuijer, Roel; Busscher, Henk J.; Qu-Ren, Yijin

    OBJECTIVE: Dental implants anchor in bone through a tight fit and osseo-integratable properties of the implant surfaces, while a protective soft tissue seal around the implants neck is needed to prevent bacterial destruction of the bone-implant interface. This tissue seal needs to form in the

  16. Postradiotherapy Dental Implant Insertion Into Bone Grafts Harvested From Nonirradiated Tissue: Case Reports.

    Science.gov (United States)

    Kimoto, Akira; Shibuya, Yasuyuki; Kobayashi, Masaki; Akashi, Masaya; Hasegawa, Takumi; Suzuki, Hiroaki; Komori, Takahide

    2016-10-01

    Prostheses and dental implants are often used to aid oral rehabilitation after surgery (with/without radiotherapy) for oral cancer. However, some studies have reported that the insertion of dental implants into irradiated bone results in a higher frequency of implant failure than the insertion of such implants in nonirradiated bone. This report describes the cases of 4 patients with oral cancer who underwent surgery and radiotherapy (total dose: 50-86 Gy) and then had dental implants inserted within the irradiated area. In each case, an ilium bone graft or a latissimus dorsi myocutaneous flap containing scapular bone was transferred to the dental implant site before the insertion of the implants. Twenty-three implants were inserted. After loading, 2 implants were lost, and 21 remained stable. In patients who have undergone radiotherapy for oral cancer, transferring bone grafts harvested from nonirradiated tissue to the irradiated site before implant insertion might help to improve dental implant survival rates.

  17. Interaction of ArF laser with dental hard tissue (AEM Study

    Directory of Open Access Journals (Sweden)

    Abbas Majdabadi

    2016-07-01

    Full Text Available Background and Aims: Nowadays lasers are used as alternatives to the tooth preparation because of reducing pain and bloodshed. The aim of this study was to observe the effect of ArF laser on the dental hard tissues. Materials and Methods: For this research human molar teeth with no caries or dental restoration and enamel cracks were used. Irradiation laser energies were taken 95, 70 and 50 mJ for enamel and 80, 70 and 50 mJ for dentine. Then, for each of energy values pulse numbers (repetition rate were adjusted at 200, 400, 600, 800, 1000 and 1500. Ablation was carried out without water spray on both enamel and dentine. Finally, the dimensions of ablated areas were measured by using a camera connected to the computer and results were applied in graphs. Results: For each energy value, the ablation dimension increased by increasing pulse numbers. Ablation depth in dentine was more than that of for enamel. Trends of graphs for dentine and enamel were the same. SEM images of ablations by 95 mJ energy on enamel and 80 mJ energy on dentine showed sharp edges. Conclusion: Ablation depths increased by increasing pulse numbers, for each energy level. However, this increase was not that as expected, because the lack of water spray while irradiating.

  18. Dental pulp stem cells immobilized in alginate microspheres for applications in bone tissue engineering.

    Science.gov (United States)

    Kanafi, M M; Ramesh, A; Gupta, P K; Bhonde, R R

    2014-07-01

    To immobilize dental pulp stem cells (DPSC) in alginate microspheres and to determine cell viability, proliferation, stem cell characteristics and osteogenic potential of the immobilized DPSCs. Human DPSCs isolated from the dental pulp were immobilized in 1% w/v alginate microspheres. Viability and proliferation of immobilized DPSCs were determined by trypan blue and MTT assay, respectively. Stem cell characteristics of DPSCs post immobilization were verified by labelling the cells with CD73 and CD90. Osteogenic potential of immobilized DPSCs was assessed by the presence of osteocalcin. Alizarin red staining and O-cresolphthalein complexone method confirmed and quantified calcium deposition. A final reverse transcriptase PCR evaluated the expression of osteogenic markers - ALP, Runx-2 and OCN. More than 80% of immobilized DPSCs were viable throughout the 3-week study. Proliferation appeared controlled and consistent unlike DPSCs in the control group. Presence of CD73 and CD90 markers confirmed the stem cell nature of immobilized DPSCs. The presence of osteocalcin, an osteoblastic marker, was confirmed in the microspheres on day 21. Mineralization assays showed high calcium deposition indicating elevated osteogenic potential of immobilized DPSCs. Osteogenic genes- ALP, Runx-2 and OCN were also upregulated in immobilized DPSCs. Surprisingly, immobilized DPSCs in the control group cultured in conventional stem cell media showed upregulation of osteogenic genes and expressed osteocalcin. Dental pulp stem cells immobilized in alginate hydrogels exhibit enhanced osteogenic potential while maintaining high cell viability both of which are fundamental for bone tissue regeneration. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  19. Effect of irradiation on the dental pulp tissues in streptozotocin-induced diabetic rats

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Ho Duk; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

    2005-03-15

    To observe the histological changes in the pulp tissues of mandibular molars in streptozotocin-induced diabetic rats after irradiation. The male Sprague-Dawley rats weighing approximately 250 gm were divided into four groups : control, diabetes, irradiation, and diabetes-irradiation groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in control and irradiation groups were injected with citrate buffer only. After 5 days, the head and neck region of the rats in irradiation and diabetes-irradiation groups were irradiated with a single absorbed dose of 10 Gy. All the rats were sacrificed at 3, 7, 14, 21, and 28 days after irradiation. The specimen including the mandibular molars were sectioned and observed using a histopathological method. In the diabetes group, capillary dilatation was observed. However, there was no obvious morphologic alteration of the odontoblasts. In the irradiation group, generalized necrosis of the dental pulp tissues was observed. Vacuolation of the odontoblasts and dilatation of the capillaries were noted in the early experimental phases. In the diabetes-irradiation group, generalized degeneration of the dental pulp tissues was observed. Vacuolation of the dental pulp cells and the odontoblasts was noted in the late experimental phases. This experiment suggest that dilatation of the capillaries in the dental pulp tissue is induced by diabetic state, and generalized degeneration of the dental pulp tissues is induced by irradiation of the diabetic group.

  20. Soft tissue augmentation around osseointegrated and uncovered dental implants: a systematic review.

    Science.gov (United States)

    Bassetti, Renzo G; Stähli, Alexandra; Bassetti, Mario A; Sculean, Anton

    2017-01-01

    The aim was to compile the current knowledge about the efficacy of different soft tissue correction methods around osseointegrated, already uncovered and/or loaded (OU/L) implants with insufficient soft tissue conditions. Procedures to increase peri-implant keratinized mucosa (KM) width and/or soft tissue volume were considered. Screening of two databases: MEDLINE (PubMed) and EMBASE (OVID), and manual search of articles were performed. Human studies reporting on soft tissue augmentation/correction methods around OU/L implants up to June 30, 2016, were considered. Quality assessment of selected full-text articles to weight risk of bias was performed using the Cochrane collaboration's tool. Overall, four randomized controlled trials (risk of bias = high/low) and five prospective studies (risk of bias = high) were included. Depending on the surgical techniques and graft materials, the enlargement of keratinized tissue (KT) ranged between 1.15 ± 0.81 and 2.57 ± 0.50 mm. The apically positioned partial thickness flap (APPTF), in combination with a free gingival graft (FGG), a subepithelial connective tissue graft (SCTG), or a xenogeneic graft material (XCM) were most effective. A coronally advanced flap (CAF) combined with SCTG in three, combined with allogenic graft materials (AMDA) in one, and a split thickness flap (STF) combined with SCTG in another study showed mean soft tissue recession coverage rates from 28 to 96.3 %. STF combined with XCM failed to improve peri-implant soft tissue coverage. The three APPTF-techniques combined with FGG, SCTG, or XCM achieved comparable enlargements of peri-implant KT. Further, both STF and CAF, both in combination with SCTG, are equivalent regarding recession coverage rates. STF + XCM and CAF + AMDA did not reach significant coverage. In case of soft tissue deficiency around OU/L dental implants, the selection of both an appropriate surgical technique and a suitable soft tissue graft material is of utmost clinical

  1. PIXE analysis of human dental cementum

    Science.gov (United States)

    Chaudhri, M. Anwar

    1984-04-01

    The elemental composition of dental cementum, from teeth of children with ages between 11 and 14 years, has been determined using the well-established PIXE technique. This was carried out in situ, that is, without having to remove the cementum from the dental roots, and thus avoiding any contamination. A number of elements, such as Na, Mg, Al, P, Cl, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Sr and Zr were detected in cementum, and their absolute concentrations determined. In certain select cases, the cementum from different parts of the same tooth was also investigated in order to study any changes in its elemental composition along the root axis.

  2. Potential of human dental stem cells in repairing the complete transection of rat spinal cord

    Science.gov (United States)

    Yang, Chao; Li, Xinghan; Sun, Liang; Guo, Weihua; Tian, Weidong

    2017-04-01

    Objective. The adult spinal cord of mammals contains a certain amount of neural precursor cells, but these endogenous cells have a limited capacity for replacement of lost cells after spinal cord injury. The exogenous stem cells transplantation has become a therapeutic strategy for spinal cord repairing because of their immunomodulatory and differentiation capacity. In addition, dental stem cells originating from the cranial neural crest might be candidate cell sources for neural engineering. Approach. Human dental follicle stem cells (DFSCs), stem cells from apical papilla (SCAPs) and dental pulp stem cells (DPSCs) were isolated and identified in vitro, then green GFP-labeled stem cells with pellets were transplanted into completely transected spinal cord. The functional recovery of rats and multiple neuro-regenerative mechanisms were explored. Main results. The dental stem cells, especially DFSCs, demonstrated the potential in repairing the completely transected spinal cord and promote functional recovery after injury. The major involved mechanisms were speculated below: First, dental stem cells inhibited the expression of interleukin-1β to reduce the inflammatory response; second, they inhibited the expression of ras homolog gene family member A (RhoA) to promote neurite regeneration; third, they inhibited the sulfonylurea receptor1 (SUR-1) expression to reduce progressive hemorrhagic necrosis; lastly, parts of the transplanted cells survived and differentiated into mature neurons and oligodendrocytes but not astrocyte, which is beneficial for promoting axons growth. Significance. Dental stem cells presented remarkable tissue regenerative capability after spinal cord injury through immunomodulatory, differentiation and protection capacity.

  3. Cryobanking of human ovarian tissue

    DEFF Research Database (Denmark)

    Macklon, Kirsten Tryde; Ernst, Erik; Andersen, Anders Nyboe

    2014-01-01

    Cryopreservation of ovarian tissue is one way of preserving fertility in young women with a malignant disease or other disorders that require gonadotoxic treatment. The purpose of the study was to explore how many women remained interested in continued cryostorage of their ovarian tissue beyond a...... women with ovarian tissue cryobanked requested continued cryostorage after an initial period of at least 5 years. The main reason for requesting disposal was successful completion of a family.......Cryopreservation of ovarian tissue is one way of preserving fertility in young women with a malignant disease or other disorders that require gonadotoxic treatment. The purpose of the study was to explore how many women remained interested in continued cryostorage of their ovarian tissue beyond...... an initial 5-year period. Between 1999 and 2006, a total of 201 girls and young women had one ovary cryopreserved for fertility preservation in Denmark. One hundred of these met our inclusion criteria, which included a follow-up period of at least 5 years, and were mailed a questionnaire. The response rate...

  4. SEM evaluation of the morphological changes in hard dental tissues prepared by Er: YAG laser and rotary instruments

    Directory of Open Access Journals (Sweden)

    Tomov Georgi

    2010-09-01

    Full Text Available Effective ablation of dental hard tissues by means of the erbium:yttrium-aluminum garnet (Er: YAG laser has been reported recently, and its application to caries removal and cavity preparation has been expected. However, few studies have investigated the morphological changes in hard dental tissues after Er: YAG laser caries treatment. In the present study the morphological changes in hard dental tissues after Er: YAG laser caries ablation in vitro was compared with that of conventional mechanical treatment. Thirty extracted human teeth with caries were used. Ten tooth was treated with the Er: YAG laser, and the other was treated with a conventional steel and diamond burs. Laser treatment was performed by means of a non-contact irradiation modes with cooling water spray, with a new Er: YAG laser (LiteTouch. Conventional bur treatment was conducted by means of a low-speed micromotor and air turbine with water cooling. Scanning electron microscope (SEM observations were performed for each treatment. The Er: YAG laser ablated carious dentin effectively with minimal thermal damage to the surrounding intact dentin, and removed infected and softened carious dentin to the same degree as the burtreatment. In addition, a lower degree of vibration was noted with the Er: YAG laser treatment. The SEM examination revealed characteristic micro-irregularities of the lased dentin and enamel surfaces with potential benefits for adhesive restorations. Our results show that the Er: YAG laser is promising as a new technical modality for caries treatment

  5. Prevalence, Type and Etiology of Dental and Soft Tissue Injuries in Children in Croatia.

    Science.gov (United States)

    Škaričić, Josip; Vuletić, Marko; Hrvatin, Sandra; Jeličić, Jesenka; Čuković-Bagić, Ivana; Jurić, Hrvoje

    2016-06-01

    The prevalence, type and etiology of dental and soft tissue injuries and relationship between the time of arrival and sustaining soft tissue injury were analyzed in this retrospective study conducted at the Department of Pediatric Dentistry, University Dental Clinic in Zagreb, Croatia, during the 2010-2014 period using documentation on 447 patients (264 male and 183 female) aged 1-16 years with injuries of primary and permanent teeth. The highest prevalence of traumatic dental injury (TDI) was found in the 7-12 age group and maxillary central incisors were most frequently affected (80.9%) in both primary and permanent dentitions. Enamel-dentin fracture without pulp exposure (31.9%) was the most common TDI of dental hard tissue in both dentitions, whereas subluxation (27.3%) was the most common periodontal tissue injury type. The most frequent location, cause and seasonal variation of trauma were at home, falling and spring. Soft tissue injuries were observed in 203 (45.4%) patients. Soft tissue injuries were less likely when fewer teeth were traumatized (ptissue injuries yielded a statistically significant difference in the time to arrival between primary and permanent teeth (ptissue injuries include bleeding and clinical presentation appears more dramatic, the time elapsed between injury and initial treatment was shorter than in non-bleeding injuries, pointing to the need of education focused on parents and school teachers regarding the importance of immediate therapy for both bleeding and non-bleeding TDIs.

  6. Cryopreserved Dental Pulp Tissues of Exfoliated Deciduous Teeth Is a Feasible Stem Cell Resource for Regenerative Medicine

    Science.gov (United States)

    Yamaza, Haruyoshi; Akiyama, Kentaro; Hoshino, Yoshihiro; Song, Guangtai; Kukita, Toshio; Nonaka, Kazuaki; Shi, Songtao; Yamaza, Takayoshi

    2012-01-01

    Human exfoliated deciduous teeth have been considered to be a promising source for regenerative therapy because they contain unique postnatal stem cells from human exfoliated deciduous teeth (SHED) with self-renewal capacity, multipotency and immunomodulatory function. However preservation technique of deciduous teeth has not been developed. This study aimed to evaluate that cryopreserved dental pulp tissues of human exfoliated deciduous teeth is a retrievable and practical SHED source for cell-based therapy. SHED isolated from the cryopreserved deciduous pulp tissues for over 2 years (25–30 months) (SHED-Cryo) owned similar stem cell properties including clonogenicity, self-renew, stem cell marker expression, multipotency, in vivo tissue regenerative capacity and in vitro immunomodulatory function to SHED isolated from the fresh tissues (SHED-Fresh). To examine the therapeutic efficacy of SHED-Cryo on immune diseases, SHED-Cryo were intravenously transplanted into systemic lupus erythematosus (SLE) model MRL/lpr mice. Systemic SHED-Cryo-transplantation improved SLE-like disorders including short lifespan, elevated autoantibody levels and nephritis-like renal dysfunction. SHED-Cryo amended increased interleukin 17-secreting helper T cells in MRL/lpr mice systemically and locally. SHED-Cryo-transplantation was also able to recover osteoporosis bone reduction in long bones of MRL/lpr mice. Furthermore, SHED-Cryo-mediated tissue engineering induced bone regeneration in critical calvarial bone-defect sites of immunocompromised mice. The therapeutic efficacy of SHED-Cryo transplantation on immune and skeletal disorders was similar to that of SHED-Fresh. These data suggest that cryopreservation of dental pulp tissues of deciduous teeth provide a suitable and desirable approach for stem cell-based immune therapy and tissue engineering in regenerative medicine. PMID:23251621

  7. Characterization of inflammatory cell infiltrate in human dental pulpitis.

    Science.gov (United States)

    Bruno, K F; Silva, J A; Silva, T A; Batista, A C; Alencar, A H G; Estrela, C

    2010-11-01

    To evaluate the microscopic characteristics and densities (per mm(2) ) of tryptase(+) mast cells, CD4(+) T helper lymphocytes, CD45RO(+) memory T lymphocytes, foxp3(+) T regulatory lymphocytes, CD20(+) B lymphocytes, CD68(+) macrophages, and CD31(+) blood vessels in human dental pulpitis (n=38) and healthy pulpal tissue (n=6). The pulps of 38 human teeth with a clinical diagnosis of irreversible pulpitis were removed by pulpectomy. The pulp tissue was immersed in 10% buffered formalin for evaluation using light microscopy. Tryptase, CD4, CD45RO, foxp3, CD20, CD68, and CD31 expressions were analysed using immunohistochemistry; other microscopic features, such as intensity of inflammatory infiltrate and collagen deposition, were evaluated using haematoxylin and eosin stain. Wilcoxon and Mann-Whitney tests were used for statistical analysis. The significance level was set at α=5%. Two microscopic patterns of pulpitis were found: group 1 (G1) (n=15) had an intense inflammatory infiltrate and mild collagen deposition; conversely, group 2 (G2) (n=23) had a scarce inflammatory infiltrate and intense collagen deposition. The numbers of CD68(+) macrophages (P=0.004) and CD20(+) B (P=0.068) lymphocytes and the density of blood vessels (P=0.002) were higher in G1 than in G2. However, a similar number of CD4(+) and CD45RO(+) T lymphocytes was found in both groups (P>0.05). When present, tryptase(+) mast cells were equally distributed in G1 and G2, whereas foxp3(+) T regulatory lymphocytes were detected in 59% and 14% of the samples of G1 and G2. Controls exhibited lower numbers of foxp3, tryptase, CD4, CD45RO, CD68 and CD20 positive cells than G1 and G2. Irreversible pulpitis had distinct microscopic features with important quantitative and qualitative differences in inflammatory cell infiltration. © 2010 International Endodontic Journal.

  8. Grating-based tomography of human tissues

    Science.gov (United States)

    Müller, Bert; Schulz, Georg; Mehlin, Andrea; Herzen, Julia; Lang, Sabrina; Holme, Margaret; Zanette, Irene; Hieber, Simone; Deyhle, Hans; Beckmann, Felix; Pfeiffer, Franz; Weitkamp, Timm

    2012-07-01

    The development of therapies to improve our health requires a detailed knowledge on the anatomy of soft tissues from the human body down to the cellular level. Grating-based phase contrast micro computed tomography using synchrotron radiation provides a sensitivity, which allows visualizing micrometer size anatomical features in soft tissue without applying any contrast agent. We show phase contrast tomography data of human brain, tumor vessels and constricted arteries from the beamline ID 19 (ESRF) and urethral tissue from the beamline W2 (HASYLAB/DESY) with micrometer resolution. Here, we demonstrate that anatomical features can be identified within brain tissue as well known from histology. Using human urethral tissue, the application of two photon energies is compared. Tumor vessels thicker than 20 μm can be perfectly segmented. The morphology of coronary arteries can be better extracted in formalin than after paraffin embedding.

  9. Dental caries vaccine

    OpenAIRE

    Shivakumar K; Vidya S; Chandu G

    2009-01-01

    Dental caries is one of the most common diseases in humans. In modern times, it has reached epidemic proportions. Dental caries is an infectious microbiologic disease of the teeth that results in localized dissolution and destruction of the calcified tissue. Dental caries is a mulitifactorial disease, which is caused by host, agent, and environmental factors. The time factor is important for the development and progression of dental caries. A wide group of microorganisms are identified from c...

  10. The CuHBr laser in hard dental tissues; Laser de CuHBr em tecidos dentais duros

    Energy Technology Data Exchange (ETDEWEB)

    Miyakawa, Walter

    2004-07-01

    In this work, it was verified the viability of characterization of laser-irradiated dental tissues in two extreme conditions: high and low absorption by the dental tissue. Comparison with light microscopy and scanning electronic microscopy revealed that these techniques are complementary each other: quantitative topographic information is directly extracted from the atomic force microscopy, while morphological aspects can be imaged by light microscopy or scanning electronic microscopy. A cavity generated by Cu-HyBrID laser in human dental enamel was also evaluated by atomic force microscopy. Structural and morphological differences between the fused and resolidified enamel from the cavity walls and the enamel from the natural tis sue were analyzed. A model, based on the Monte Carlo method described the propagation of CuHBr laser radiation and the absorbed energy distribution in dental tissues. Experimental measures with a CCD camera were used to semiquantitatively characterize the scattered light distribution in the tooth and they corroborated the model. It was observed that Rayleigh scattering and diffuse scattered radiation is predominant. The absorbed energy distribution map and the temperature variation along the beam propagation axis presented strong dependence with the absorption coefficient of the dental enamel and they cannot be deduced from the light distribution profile. The exposure time threshold for dental enamel melting and evaporation, irradiated by a specific condition of the green line of the Cu-HyBrID laser, was determined and a phenomenological model was discussed for the laser-matter interaction, based on pulse accumulation effect. Theoretical temperature calculations associated with experimental evidences strongly suggest that optical and thermal parameters should vary with temperature. The obtained exposure time threshold should correspond to the time necessary to the sample reach the critical temperature, at which the increase of absorption

  11. NCI’s Cooperative Human Tissue Network

    Science.gov (United States)

    Quality biospecimens are a foundational resource for cancer research. One of NCI’s longest running biospecimen programs is the Cooperative Human Tissue Network, a resource mainly for basic discovery and early translational research.

  12. Human dental follicle cells express embryonic, mesenchymal and neural stem cells markers.

    Science.gov (United States)

    Lima, Rodrigo Lopes; Holanda-Afonso, Rosenilde Carvalho; Moura-Neto, Vivaldo; Bolognese, Ana Maria; DosSantos, Marcos Fabio; Souza, Margareth Maria

    2017-01-01

    This study was conducted to identify and characterize dental follicle stem cells (DFSCs) by analyzing expression of embryonic, mesenchymal and neural stem cells surface markers. Design Dental follicle cells (DFCs) were evaluated by immunocytochemistry using embryonic stem cells markers (OCT4 and SOX2), mesenchmal stem cells (MSCs) markers (Notch1, active Notch1, STRO, CD44, HLA-ABC, CD90), neural stem cells markers (Nestin and β-III-tubulin), neural crest stem cells (NCSCs) markers (p75 and HNK1) and a glial cells marker (GFAP). RT-PCR was performed to identify the expression of OCT4 and NANOG in DFCs and dental follicle tissue. Immunocytochemistry and RT-PCR analysis revealed that a significant proportion of the DFCs evaluated expressed human embryonic stem cells marker OCT4 (75%) whereas NANOG was weakly expressed. A considerable amount of MSCs (90%) expressed Notch1, STRO, CD44 and HLA-ABC. However, they were weakly positive for CD90. Moreover, it was possible to demonstrate that dental follicle contains a significant proportion of neural stem/progenitors cells, expressing β-III-tubulin (90%) and nestin (70%). Interestingly, immunocytochemistry showed DFCs positive for p75 (50%), HNK1 (cells. This is the first study reporting the presence of NCSCs and glial-like cells in the dental follicle. The results of the present study suggest the occurrence of heterogeneous populations of stem cells, particularly neural stem/progenitor cells, in the dental follicle, Therefore, the human dental follicle might be a promising source of adult stem cells for regenerative purposes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Measurements of scattering anisotropy in dental tissue and zirconia ceramic

    Science.gov (United States)

    Fernández-Oliveras, Alicia; Pecho, Oscar E.; Rubiño, Manuel; Pérez, María M.

    2012-06-01

    Knowledge of the optical properties of biological structures is useful for clinical applications, especially when dealing with incoming biomaterials engineered to improve the benefits for the patient. One ceramic material currently used in restorative dentistry is yttrium cation-doped tetragonal zirconia polycrystal (3Y-TZP) because of its good mechanical properties. However, its optical properties have not been thoroughly studied. Many methods for the determination of optical parameters from biological media make the assumption that scattered light is isotropically distributed over all angles. Nevertheless, real biological materials may have an angular dependence on light scattering, which may affect the optical behaviour of the materials. Therefore, the recovery of the degree of anisotropy in the scattering angular distribution is important. The phase function that represents the scattering angular distribution is usually characterized by the anisotropy coefficient g, which equals the average cosine of the scattering angle. In this work, we measured angularscattering distributions for two zirconia ceramic samples, pre-sintered and sintered, with similar thicknesses (0.48 mm and 0.50 mm, respectively) and also for a human dentine sample (0.41 mm in thickness). The samples were irradiated with a He-Ne laser beam (λ = 632.8 nm) and the angular-scattering distributions were measured using a rotating goniometer. The g values yielded were: -0.7970 +/- 0.0016 for pre-sintered zirconia, -0.2074 +/- 0.0024 for sintered zirconia and 0.0620 +/- 0.0010 for dentine. The results show that zirconia sintering results in optical behaviour more similar to those of dentine tissue, in terms of scattering anisotropy.

  14. Melanin content of hamster tissues, human tissues, and various melanomas

    Energy Technology Data Exchange (ETDEWEB)

    Watts, K.P.; Fairchild, R.G.; Slatkin, D.N.; Greenberg, D.; Packer, S.; Atkins, H.L.; Hannon, S.J.

    1981-02-01

    Melanin content (percentage by weight) was determined in both pigmented and nonpigmented tissues of Syrian golden hamsters bearing Greene melanoma. Melanin content was also measured in various other melanoma models (B-16 in C57 mice, Harding-Passey in BALB/c mice, and KHDD in C3H mice) and in nine human melanomas, as well as in selected normal tissues. The purpose was to evaluate the possible efficacy of chlorpromazine, which is known to bind to melanin, as a vehicle for boron transport in neutron capture therapy. Successful therapy would depend upon selective uptake and absolute concentration of borated compounds in tumors; these parameters will in turn depend upon melanin concentration in melanomas and nonpigmented ''background'' tissues. Hamster whole eyes, hamster melanomas, and other well-pigmented animal melanomas were found to contain 0.3 to 0.8% melanin by weight, whereas human melanomas varied from 0.1 to 0.9% (average, 0.35%). Other tissues, with the exception of skin, were lower in content by a factor of greater than or equal to30. Melanin pigment was extracted from tissues, and the melanin content was determined spectrophotometrically. Measurements were found to be sensitive to the presence of other proteins. Previous procedures for isolating and quantifying melanin often neglected the importance of removing proteins and other interfering nonmelanic substances.

  15. Investigating the Vascularization of Tissue-Engineered Bone Constructs Using Dental Pulp Cells and 45S5 Bioglass(®) Scaffolds.

    OpenAIRE

    El-Gendy, R; J Kirkham; Newby, PJ; Mohanram, Y; Boccaccini, AR; Yang, XB

    2015-01-01

    Identification of a suitable cell source combined with an appropriate 3D scaffold is an essential prerequisite for successful engineering of skeletal tissues. Both osteogenesis and angiogenesis are key processes for bone regeneration. This study investigated the vascularization potential of a novel combination of human dental pulp stromal cells (HDPSCs) with 45S5 Bioglass(®) scaffolds for tissue-engineered mineral constructs in vivo and in vitro. 45S5 Bioglass scaffolds were produced by the f...

  16. Galactosylceramide lipidosis (Krabbe's disease) and deciduous dental tissues. A case report.

    Science.gov (United States)

    Bloch-Zupan, A; Lécolle, S; Goldberg, M

    1994-07-01

    The deciduous teeth of a 5-year-old girl affected by a protracted type of infantile globoid-cell leukodystrophy or Krabbe's disease, a galactosylceramide lipidosis, were examined with the scanning and transmission electron microscopes. The diagnosis was established on the basis of galactosylceramidase activity (0.04 mu katal/kg proteins versus 0.86 +/- 0.49 in the normal situation) and abnormalities in the white matter and trouble in myelinization assessed by magnetic resonance imaging. In spite of the fact that enamel, dentin and pulp are extraneural tissues, they were also affected by the disease. Ultrastructural observations of dental mineralized tissues revealed enamel hypoplasia as well as abnormal proteinaceous lamina and hypomineralized lines or bands. Inside the mantle dentin, dendritic inclusions of amorphous material were seen. Lysosomal storage inclusions were observed in all the cells of the dental pulp. The myelin sheaths of dental peripheral nerves displayed severe degenerative changes. Proliferation of dentinoclasts contributed to stimulate root resorption.

  17. Detection for demineralization of dental hard tissues using index-sequenced radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dong Hyun; Park, Young Ho; Kim, Kyung Sook; Park, Jeong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Hun Kuk [Department of Biomedical Engineering, School of Medicine, KyungHee University, Seoul (Korea, Republic of); Choi, Yong Suk; Hwang, Eui Hwan [Department of Oral and Maxillofacial Radiology, Institute of Oral Biology, School of Dentistry, KyungHee University, Seoul (Korea, Republic of)

    2009-06-15

    The purpose of this study was to develop the radiographic technique for detecting the demineralization which is known as indication of dental caries. This technique was based on the comparing of multiple radiographs which was irradiated by multiple X-ray spectra. For the meaningful comparing, the multiple radiographs were reconstructed to the dosimetrically consistent images using a standard material. The difference of resulting images of same target with multiple spectra represents the difference of response of material as regards the spectra. We have found about 10% of demineralization of dental hard tissues particularly in the proximal region through the analyzing of differences. Most intriguing thing in this investigation was that the method to analyze difference shows us to an anatomic structure of dental hard tissues even if absolute values of optical density were excluded during the procedures.

  18. Theory analysis of the Dental Hygiene Human Needs Conceptual Model.

    Science.gov (United States)

    MacDonald, L; Bowen, D M

    2017-11-01

    Theories provide a structural knowing about concept relationships, practice intricacies, and intuitions and thus shape the distinct body of the profession. Capturing ways of knowing and being is essential to any professions' practice, education and research. This process defines the phenomenon of the profession - its existence or experience. Theory evaluation is a systematic criterion-based assessment of a specific theory. This study presents a theory analysis of the Dental Hygiene Human Needs Conceptual Model (DH HNCM). Using the Walker and Avant Theory Analysis, a seven-step process, the DH HNCM, was analysed and evaluated for its meaningfulness and contribution to dental hygiene. The steps include the following: (i) investigate the origins; (ii) examine relationships of the theory's concepts; (iii) assess the logic of the theory's structure; (iv) consider the usefulness to practice; (v) judge the generalizability; (vi) evaluate the parsimony; and (vii) appraise the testability of the theory. Human needs theory in nursing and Maslow's Hierarchy of Need Theory prompted this theory's development. The DH HNCM depicts four concepts based on the paradigm concepts of the profession: client, health/oral health, environment and dental hygiene actions, and includes validated eleven human needs that evolved overtime to eight. It is logical, simplistic, allows scientific predictions and testing, and provides a unique lens for the dental hygiene practitioner. With this model, dental hygienists have entered practice, knowing they enable clients to meet their human needs. For the DH HNCM, theory analysis affirmed that the model is reasonable and insightful and adds to the dental hygiene professions' epistemology and ontology. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Clonality evaluation in human tissues

    Directory of Open Access Journals (Sweden)

    Villamizar-Rivera, Nicolás

    2015-07-01

    Full Text Available Malignant proliferations are usually clonal. While most times the biological potential can be established through routine pathologic and clinical examinations, some cases are difficult to classify. Moreover, in some situations there are dominant clones whose analysis is important, such as in autoimmune diseases and immunodeficiency. This paper presents in an understandable way the main techniques for the study of clonality, namely: evaluation of gene rearrangements of antigen receptor, and evaluation of human antigen receptor gene.

  20. Rat Dental Pulp Tissue Reaction After Capped With Propolis Derived Non Flavonoid Extract

    OpenAIRE

    Ardo Sabir, Dr.drg. M.Kes

    2011-01-01

    Therefore, present result suggest that application of non-flavonoids propolis extract on rats dental pulp tissue might inhibit inflammatory process. Propolis is a resinous material colled by honey bees from various plants. Many researches have showed that it has antibacterial and anti-inflammation activities.

  1. Hard tissue formation of STRO-1-selected rat dental pulp stem cells in vivo.

    NARCIS (Netherlands)

    Yang, X.; Walboomers, X.F.; Beucken, J.J.J.P. van den; Bian, Z.; Fan, M.; Jansen, J.A.

    2009-01-01

    The objective of this study was to examine hard tissue formation of STRO-1-selected rat dental pulp-derived stem cells, seeded into a calcium phosphate ceramic scaffold, and implanted subcutaneously in mice. Previously, STRO-1 selection was used to obtain a mesenchymal stem cell progenitor

  2. [The influence of orthodontic treatment on dental pulp and periapical tissues].

    Science.gov (United States)

    Zhang, Xiaowei; Liang, Jingping

    2016-05-01

    The pathogenesis of pulpal and periapical diseases is related with not only bacterial infection but also physicochemical irritations such as trauma and thermal changes. During orthodontic therapy, the application of orthodontic forces on teeth may produce a series of changes in periodontal ligament, alveolar bone and pulpo-dentinal complex. This article reviewed the influences of orthodontic therapy on dental pulp and periapical tissues.

  3. A study of tooth brushing pattern and its effects on dental tissues in ...

    African Journals Online (AJOL)

    Objective: To determine the tooth brushing patterns among Obafemi Awolowo University (OAU) students and the effects on dental tissues. Method: A convenient sampling technique was used to select 100 undergraduate students of the Obafemi Awolowo University. A self administered questionnaire designed to determine ...

  4. Viscoelastic Properties of Dental Pulp Tissue and Ramifications on Biomaterial Development for Pulp Regeneration.

    Science.gov (United States)

    Erisken, Cevat; Kalyon, Dilhan M; Zhou, Jian; Kim, Sahng G; Mao, Jeremy J

    2015-10-01

    A critical step in biomaterial selection effort is the determination of material as well as the biological properties of the target tissue. Previously, the selection of biomaterials and carriers for dental pulp regeneration has been solely based on empirical experience. In this study, first, the linear viscoelastic material functions and compressive properties of miniature pig dental pulp were characterized using small-amplitude oscillatory shear and uniaxial compression at a constant rate. They were then compared with the properties of hydrogels (ie, agarose, alginate, and collagen) that are widely used in tissue regeneration. The comparisons of the linear viscoelastic material functions of the native pulp tissue with those of the 3 hydrogels revealed the gel-like behavior of the pulp tissue over a relatively large range of time scales (ie, over the frequency range of 0.1-100 rps). At the constant gelation agent concentration of 2%, the dynamic properties (ie, storage and loss moduli and the tanδ) of the collagen-based gel approached those of the native tissue. Under uniaxial compression, the peak normal stresses and compressive moduli of the agarose gel were similar to those of the native tissue, whereas alginate and collagen exhibited significantly lower compressive properties. The linear viscoelastic and uniaxial compressive properties of the dental pulp tissue reported here should enable the more appropriate selection of biogels for dental pulp regeneration via the better tailoring of gelation agents and their concentrations to better mimic the dynamic and compressive properties of native pulp tissue. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  5. The Human Odontoblast Cell Layer and Dental Pulp Proteomes and N-Terminomes.

    Science.gov (United States)

    Abbey, S R; Eckhard, U; Solis, N; Marino, G; Matthew, I; Overall, C M

    2017-10-01

    The proteome and N-terminome of the human odontoblast cell layer were identified for the first time by shotgun proteomic and terminal amine isotopic labeling of substrates (TAILS) N-terminomic analyses, respectively, and compared with that of human dental pulp stroma from 26 third molar teeth. After reverse-phase liquid chromatography-tandem mass spectrometry, >170,000 spectra from the shotgun and TAILS analyses were matched by 4 search engines to 4,888 and 12,063 peptides in the odontoblast cell layer and pulp stroma, respectively. Within these peptide groups, 1,543 and 5,841 protein N-termini, as well as 895 and 2,423 unique proteins, were identified with a false discovery rate of ≤1%. Thus, the human dental pulp proteome was expanded by 974 proteins not previously identified among the 4,123 proteins in our 2015 dental pulp study. Further, 222 proteins of the odontoblast cell layer were not found in the pulp stroma, suggesting many of these proteins are synthesized only by odontoblasts. When comparing the proteomes of older and younger donors, differences were more apparent in the odontoblast cell layer than in the dental pulp stroma. In the odontoblast cell layer proteome, we found proteomic evidence for dentin sialophosphoprotein, which is cleaved into dentin sialoprotein and dentin phosphoprotein. By exploring the proteome of the odontoblast cell layer and expanding the known dental pulp proteome, we found distinct proteome differences compared with each other and with dentin. Moreover, between 61% and 66% of proteins also occurred as proteoforms commencing with a neo-N-terminus not annotated in UniProt. Hence, TAILS increased proteome coverage and revealed considerable proteolytic processing, by identifying stable proteoforms in these dynamic dental tissues. All mass spectrometry raw data have been deposited to ProteomeXchange with the identifier , with the accompanying metadata at Mendeley Data ( https://data.mendeley.com/datasets/b57zfh6wmy/1 ).

  6. Immunomodulatory properties and in vivo osteogenesis of human dental stem cells from fresh and cryopreserved dental follicles.

    Science.gov (United States)

    Kang, Young-Hoon; Lee, Hye-Jin; Jang, Si-Jung; Byun, June-Ho; Lee, Jong-Sil; Lee, Hee-Chun; Park, Won-Uk; Lee, Jin-Ho; Rho, Gyu-Jin; Park, Bong-Wook

    2015-01-01

    In our previous study, dental follicle tissues from extracted wisdom teeth were successfully cryopreserved for use as a source of stem cells. The goals of the present study were to investigate the immunomodulatory properties of stem cells from fresh and cryopreserved dental follicles (fDFCs and cDFCs, respectively) and to analyze in vivo osteogenesis after transplantation of these DFCs into experimental animals. Third passage fDFCs and cDFCs showed similar expression levels of interferon-γ receptor (CD119) and major histocompatibility complex class I and II (MHC I and MHC II, respectively), with high levels of CD119 and MHC I and nearly no expression of MHC II. Both fresh and cryopreserved human DFCs (hDFCs) were in vivo transplanted along with a demineralized bone matrix scaffold into mandibular defects in miniature pigs and subcutaneous tissues of mice. Radiological and histological evaluations of in vivo osteogenesis in hDFC-transplanted sites revealed significantly enhanced new bone formation activities compared with those in scaffold-only implanted control sites. Interestingly, at 8 weeks post-hDFC transplantation, the newly generated bones were overgrown compared to the original size of the mandibular defects, and strong expression of osteocalcin and vascular endothelial growth factor were detected in the hDFCs-transplanted tissues of both animals. Immunohistochemical analysis of CD3, CD4, and CD8 in the ectopic bone formation sites of mice showed significantly decreased CD4 expression in DFCs-implanted tissues compared with those in control sites. These findings indicate that hDFCs possess immunomodulatory properties that involved inhibition of the adaptive immune response mediated by CD4 and MHC II, which highlights the usefulness of hDFCs in tissue engineering. In particular, long-term preserved dental follicles could serve as an excellent autologous or allogenic stem cell source for bone tissue regeneration as well as a valuable therapeutic agent for

  7. Mechanical properties of bone tissues surrounding dental implant systems with different treatments and healing periods.

    Science.gov (United States)

    Kim, Do-Gyoon; Kwon, Hyun-Jung; Jeong, Yong-Hoon; Kosel, Erin; Lee, Damian J; Han, Jung-Suk; Kim, Hye-Lee; Kim, Dae-Joon

    2016-11-01

    The objective of the current study was to examine whether the nanoindentation parameters can assess the alteration of bone quality resulting from different degrees of bone remodeling between bone tissue ages around the dental implant interface with different treatments and healing periods. Dental implants were placed in mandibles of six male dogs. Treatment groups included: resorbable blast media-treated titanium (Ti) implants, alumina-blasted zirconia implants (ATZ), alumina-blasted zirconia implants applied with demineralized bone matrix (ATZ-D), and alumina-blasted zirconia implants applied with rhBMP-2 (ATZ-B). Nanoindentation modulus (E), hardness (H), viscosity (η), and viscoelastic creep (Creep/P max) were measured for new and old bone tissues adjacent to the implants at 3 and 6 weeks of post-implantation. A total of 945 indentations were conducted for 32 implant systems. Significantly lower E, H, and η but higher Creep/P max were measured for new bone tissues than old bone tissues, independent of treatments at both healing periods (p  0.568). ATZ-D and ATZ-B implants had the stiffer slope of correlation between E and Creep/P max of the new bone tissue than Ti implant (p implant can provide more detailed information to understand mechanical behavior of an implant system. Ability of energy absorption in the interfacial bone tissue can play a significant role in the long-term success of a dental implant system.

  8. Analysis of Artificial Radiocarbon in Different Skeletal and Dental Tissue Types to Evaluate Date of Death

    Energy Technology Data Exchange (ETDEWEB)

    Ubelaker, D H; Buchholz, B A; Stewart, J

    2005-07-19

    Radiocarbon dating, with special reference to the modern bomb-curve, can provide useful information to elucidate the date of death of skeletonized human remains. Interpretation can be enhanced with analysis of different types of tissues within a single skeleton because of the known variability of formation times and remodeling rates. Analysis of radiocarbon content of teeth, especially the enamel in tooth crowns provides information about the date of formation in the childhood years and in consideration of the known timing of tooth formation can be used to estimate the birth date after 1950 A.D. Radiocarbon analysis of modern cortical and trabecular bone samples from the same skeleton may allow proper placement on the pre-1963 or post-1963 sides of the bomb-curve since most trabecular bone generally undergoes more rapid remodeling than does most cortical bone. Pre-1963 bone formation would produce higher radiocarbon values for most trabecular bone than for most cortical bone. This relationship is reversed for formation after 1963. Radiocarbon analysis was conducted in this study on dental, cortical and trabecular bone samples from two adult individuals of known birth (1925 and 1926) and death dates (1995 and 1959). As expected, the dental results correspond to pre-bomb bomb-curve values reflecting conditions during the childhoods of the individuals. The curve radiocarbon content of most bone samples reflected the higher modern bomb-curve values. Within the bone sample analyses, the values of the trabecular bone were higher than those of cortical bone and supported the known placement on the pre-1963 side of the bomb-curve.

  9. Hypoxia enhances the angiogenic potential of human dental pulp cells.

    Science.gov (United States)

    Aranha, Andreza M F; Zhang, Zhaocheng; Neiva, Kathleen G; Costa, Carlos A S; Hebling, Josimeri; Nör, Jacques E

    2010-10-01

    Trauma can result in the severing of the dental pulp vessels, leading to hypoxia and ultimately to pulp necrosis. Improved understanding of mechanisms underlying the response of dental pulp cells to hypoxic conditions might lead to better therapeutic alternatives for patients with dental trauma. The purpose of this study was to evaluate the effect of hypoxia on the angiogenic response mediated by human dental pulp stem cells (DPSCs) and human dental pulp fibroblasts (HDPFs). DPSCs and HDPFs were exposed to experimental hypoxic conditions. Hypoxia-inducible transcription factor-1alpha (HIF-1alpha) was evaluated by Western blot and immunocytochemistry, whereas vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) expression was evaluated by enzyme-linked immunosorbent assay. YC-1, an inhibitor of HIF-1alpha, was used to evaluate the functional effect of this transcriptional factor on hypoxia-induced VEGF expression. Conditioned medium from hypoxic and normoxic pulp cells was used to stimulate human dermal microvascular endothelial cells (HDMECs). HDMEC proliferation was measured by WST-1 assay, and angiogenic potential was evaluated by a capillary sprouting assay in 3-dimensional collagen matrices. Hypoxia enhanced HIF-1alpha and VEGF expression in DPSCs and HDPFs. In contrast, hypoxia did not induce bFGF expression in pulp cells. YC-1 partially inhibited hypoxia-induced HIF-1alpha and VEGF in these cells. The growth factor milieu of hypoxic HDPFs (but not hypoxic DPSCs) induced endothelial cell proliferation and sprouting as compared with medium from normoxic cells. Collectively, these data demonstrate that hypoxia induces complex and cell type-specific pro-angiogenic responses and suggest that VEGF (but not bFGF) participates in the revascularization of hypoxic dental pulps. Copyright © 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  10. Two Distinct Processes of Bone-like Tissue Formation by Dental Pulp Cells after Tooth Transplantation

    Science.gov (United States)

    Yukita, Akira; Yoshiba, Kunihiko; Yoshiba, Nagako; Takahashi, Masafumi; Nakamura, Hiroaki

    2012-01-01

    Dental pulp is involved in the formation of bone-like tissue in response to external stimuli. However, the origin of osteoblast-like cells constructing this tissue and the mechanism of their induction remain unknown. We therefore evaluated pulp mineralization induced by transplantation of a green fluorescent protein (GFP)–labeled tooth into a GFP-negative hypodermis of host rats. Five days after the transplantation, the upper pulp cavity became necrotic; however, cell-rich hard tissue was observed adjacent to dentin at the root apex. At 10 days, woven bone-like tissue was formed apart from the dentin in the upper pulp. After 20 days, these hard tissues expanded and became histologically similar to bone. GFP immunoreactivity was detected in the hard tissue-forming cells within the root apex as well as in the upper pulp. Furthermore, immunohistochemical observation of α–smooth muscle actin, a marker for undifferentiated cells, showed a positive reaction in cells surrounding this bone-like tissue within the upper pulp but not in those within the root apex. Immunoreactivities of Smad4, Runx2, and Osterix were detected in the hard tissue-forming cells within both areas. These results collectively suggest that the dental pulp contains various types of osteoblast progenitors and that these cells might thus induce bone-like tissue in severely injured pulp. PMID:22899860

  11. Antifungal Effect of a Dental Tissue Conditioner Containing Nystatin-Loaded Alginate Microparticles.

    Science.gov (United States)

    Kim, Hyun-Jin; Son, Jun Sik; Kwon, Tae-Yub

    2018-02-01

    In this in vitro study, nystatin-alginate microparticles were successfully fabricated to control the release of nystatin from a commercial dental tissue conditioner. These nystatin-alginate microparticles were spherical and had a slightly rough surface. The microparticles incorporated into the tissue conditioner were distributed homogeneously throughout the tissue conditioner matrix. The incorporation of the microparticles did not deteriorate the mechanical properties of the original material. The agar diffusion test results showed that the tissue conditioner containing the microparticles had a good antifungal effect against Candida albicans. The nystatin-alginate microparticles efficiently controlled the release of nystatin from the tissue conditioner matrix over the experimental period of 14 days. Moreover, the nystatin-alginate microparticles incorporated in the tissue conditioner showed effective antifungal function even at lower concentrations of nystatin. The current study suggests that the tissue conditioner containing the nystatin-alginate microparticle carrier system has potential as an effective antifungal material.

  12. [Hard dental tissue minimal-invasive preparation using contemporary polymer rotating instruments and laser].

    Science.gov (United States)

    Beloica, Milos; Vulićević, Zoran R; Mandinić, Zoran; Radović, Ivana; Jovicić, Olivera; Carević, Momir; Tekić, Jasmina

    2014-01-01

    Goal of contemporary dentistry is to decrease the patient's discomfort during treatment. Dentists aim to achieve maximum with the newly developed dental materials as well as with new cavity preparation techniques in the shortest time span. Since the development of the first constructed borer (drilling machine) for caries removal, the preparation techniques have considerably changed. The progress of dental materials as well as the cavity preparation techniques has led us to contemporary carbide tungsten and diamond borers that are used with obligatory water cooling. The innovation within this field represents newly developed polymer borers that can detect the difference between carious lesions and healthy tooth structure. In this way the cavity preparation may be performed without damaging dental healthy tissue. This is possible owing to their hardness which is lower than the hardness of intact dentin. Polymer borer preparation is painless with less vibration, while the increase in temperature is negligible. Lasers have been used in clinical dentistry since 1980s so it can be said that they represent a new technology. The function of lasers is based on ablation which requires water. Erbium lasers have shown the highest potential with their ability to produce effective ablation of hard dental tissues. Laser application in dentistry requires special training as well as some protective measures. Laser advantages, compared to traditional preparation techniques, involve the absence of vibration, painless preparation, possibility of preparation without anesthetic and easier patient's adjustment to dental intervention which is of importance, especially in pediatric dentistry.

  13. Dental Pulp and Dentin Tissue Engineering and Regeneration – Advancement and Challenge

    Science.gov (United States)

    Huang, George T.-J.

    2012-01-01

    Hard tissue is difficult to repair especially dental structures. Tooth enamel is incapable of self-repairing whereas dentin and cememtum can regenerate with limited capacity. Enamel and dentin are commonly under the attack by caries. Extensive forms of caries destroy enamel and dentin and can lead to dental pulp infection. Entire pulp amputation followed by the pulp space disinfection and filled with an artificial rubber-like material is employed to treat the infection --commonly known as root canal or endodontic therapy. Regeneration of dentin relies on having vital pulps; however, regeneration of pulp tissue has been difficult as the tissue is encased in dentin without collateral blood supply except from the root apical end. With the advent of modern tissue engineering concept and the discovery of dental stem cells, regeneration of pulp and dentin has been tested. This article will review the recent endeavor on pulp and dentin tissue engineering and regeneration. The prospective outcome of the current advancement and challenge in this line of research will be discussed. PMID:21196351

  14. Three-dimensional simulation of human teeth and its application in dental education and research.

    Science.gov (United States)

    Koopaie, Maryam; Kolahdouz, Sajad

    2016-01-01

    Background: A comprehensive database, comprising geometry and properties of human teeth, is needed for dentistry education and dental research. The aim of this study was to create a three-dimensional model of human teeth to improve the dental E-learning and dental research. Methods: In this study, a cross-section picture of the three-dimensional model of the teeth was used. CT-Scan images were used in the first method. The space between the cross- sectional images was about 200 to 500 micrometers. Hard tissue margin was detected in each image by Matlab (R2009b), as image processing software. The images were transferred to Solidworks 2015 software. Tooth border curve was fitted on B-spline curves, using the least square-curve fitting algorithm. After transferring all curves for each tooth to Solidworks, the surface was created based on the surface fitting technique. This surface was meshed in Meshlab-v132 software, and the optimization of the surface was done based on the remeshing technique. The mechanical properties of the teeth were applied to the dental model. Results: This study presented a methodology for communication between CT-Scan images and the finite element and training software through which modeling and simulation of the teeth were performed. In this study, cross-sectional images were used for modeling. According to the findings, the cost and time were reduced compared to other studies. Conclusion: The three-dimensional model method presented in this study facilitated the learning of the dental students and dentists. Based on the three-dimensional model proposed in this study, designing and manufacturing the implants and dental prosthesis are possible.

  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. © 2016 Wiley Periodicals, Inc.

  16. Human treated dentin matrix as a natural scaffold for complete human dentin tissue regeneration.

    Science.gov (United States)

    Li, Rui; Guo, Weihua; Yang, Bo; Guo, Lijuan; Sheng, Lei; Chen, Gang; Li, Ye; Zou, Qing; Xie, Dan; An, Xiaoxue; Chen, Yali; Tian, Weidong

    2011-07-01

    An essential aspect of tooth tissue engineering is the identification of suitable scaffolding materials to support cell growth and tissue regeneration. Treated dentin matrix (TDM) from a rat has recently been shown to be a suitable scaffold for rat dentin regeneration. However, due to species-specific differences, it remains unclear whether a similar fabrication method can be extended to human TDM and human dentin regeneration. Therefore, this present study explored the biological response to a human TDM (hTDM) created using a modified dentin treatment method. Various biological characteristics, including cell proliferation, cell migration, cell viability, and cytotoxity were investigated. To assess the inductive capacity of hTDM, dental follicle cells (DFCs) were combined with hTDM and were implanted in vivo for 8 weeks in a mouse model. The resulting grafts were studied histologically. The results showed hTDM released dentinogenic factors, indicating that hTDM could play a sustained role in odontogenesis. DFC attachment, growth, viability, and cytotoxicity on the surface of hTDM showed a notable improvement over those on calcium phosphate controls. Most importantly, in vivo hTDM induced and supported regeneration of complete dentin tissues, which expressed dentin markers DSP and DMP-1. As cells in and around the regenerated dentin were positive for human mitochondria, implanted DFCs and hTDM were responsible for the regenerated dentin tissues. In conclusion, hTDM is indicated as an ideal biomaterial for human dentin regeneration. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Immunohistochemical characterization of human olfactory tissue.

    Science.gov (United States)

    Holbrook, Eric H; Wu, Enming; Curry, William T; Lin, Derrick T; Schwob, James E

    2011-08-01

    The pathophysiology underlying human olfactory disorders is poorly understood because biopsying the olfactory epithelium (OE) can be unrepresentative and extensive immunohistochemical analysis is lacking. Autopsy tissue enriches our grasp of normal and abnormal olfactory immunohistology and guides the sampling of the OE by biopsy. Furthermore, a comparison of the molecular phenotype of olfactory epithelial cells between rodents and humans will improve our ability to correlate human histopathology with olfactory dysfunction. An immunohistochemical analysis of human olfactory tissue using a comprehensive battery of proven antibodies. Human olfactory mucosa obtained from 21 autopsy specimens was analyzed with immunohistochemistry. The position and extent of olfactory mucosa was assayed by staining whole mounts (WMs) with neuronal markers. Sections of the OE were analyzed with an extensive group of antibodies directed against cytoskeletal proteins and transcription factors, as were surgical specimens from an esthesioneuroblastoma. Neuron-rich epithelium is always found inferior to the cribriform plate, even at advanced age, despite the interruptions in the neuroepithelial sheet caused by patchy respiratory metaplasia. The pattern of immunostaining with our antibody panel identifies two distinct types of basal cell progenitors in human OE similar to rodents. The panel also clarifies the complex composition of esthesioneuroblastoma. The extent of human olfactory mucosa at autopsy can easily be delineated as a function of age and neurologic disease. The similarities in human versus rodent OE will enable us to translate knowledge from experimental animals to humans and will extend our understanding of human olfactory pathophysiology. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

  18. A method for rapid measurement of laser ablation rate of hard dental tissue

    Science.gov (United States)

    Perhavec, T.; Gorkič, A.; Bračun, D.; Diaci, J.

    2009-06-01

    The aim of the study reported here is the development of a new method which allows rapid and accurate in-vitro measurements of three-dimensional (3D) shape of laser ablated craters in hard dental tissues and the determination of crater volume, ablation rate and speed. The method is based on the optical triangulation principle. A laser sheet projector illuminates the surface of a tooth, mounted on a linear translation stage. As the tooth is moved by the translation stage a fast digital video camera captures series of images of the illuminated surface. The images are analyzed to determine a 3D model of the surface. Custom software is employed to analyze the 3D model and to determine the volume of the ablated craters. Key characteristics of the method are discussed as well as some practical aspects pertinent to its use. The method has been employed in an in-vitro study to examine the ablation rates and speeds of the two main laser types currently employed in dentistry, Er:YAG and Er,Cr:YSGG. Ten samples of extracted human molar teeth were irradiated with laser pulse energies from 80 mJ to the maximum available energy (970 mJ with the Er:YAG, and 260 mJ with the Er,Cr:YSGG). About 2000 images of each ablated tooth surface have been acquired along a translation range of 10 mm, taking about 10 s and providing close to 1 million surface measurement points. Volumes of 170 ablated craters (half of them in dentine and the other half in enamel) were determined from this data and used to examine the ablated volume per pulse energy and ablation speed. The results show that, under the same conditions, the ablated volume per pulse energy achieved by the Er:YAG laser exceeds that of the Er,Cr:YSGG laser in almost all regimes for dentine and enamel. The maximum Er:YAG laser ablation speeds (1.2 mm 3/s in dentine and 0.7 mm 3/s in enamel) exceed those obtained by the Er,Cr:YSGG laser (0.39 mm 3/s in dentine and 0.12 mm 3/s in enamel). Since the presented method proves to be easy to

  19. Influence of peak power in ablation rate of dental hard tissues: mathematical model

    Science.gov (United States)

    Colojoara, Carmen; Gabay, Shimon; van der Meulen, Freerk W.; van Gemert, Martin J. C.

    1996-12-01

    Pulsed Er:YAG and CO2 lasers should be suitable instruments for dentin and enamel ablation because both tissues have absorption peaks for radiation at 2.9 and 9.6 micrometers wavelengths. This is the context of our research that emphasizes the way in which the diameter and the depth of the crater made in enamel and dentin with the laser Er:YAG and CO2 is influenced in quantity and quality. Freshly extracted human third molar were used for this experiment. The laser source is Er:YAG Kavo Key dental model 1240 and CO2 Laser Sonics LS 860. The dimensions of the obtained craters were measured using the optical microscopy method. The obtained results were modelled experimentally with programs: GRAPHER and STATGRAPHICS. After the mathematical processing to the results what we obtain is relevant regarding the influence of the key parameters in the efficiency of the ablation according to the type of laser. On the whole, from our research results that both lasers ablate efficiently the dentin when the laser energy is between 200 and 300 mJ.

  20. Anisotropic local physical properties of human dental enamel in comparison to properties of some common dental filling materials.

    Science.gov (United States)

    Raue, Lars; Hartmann, Christiane D; Rödiger, Matthias; Bürgers, Ralf; Gersdorff, Nikolaus

    2014-11-01

    A major aspect in evaluating the quality of dental materials is their physical properties. Their properties should be a best fit of the ones of dental hard tissues. Manufacturers give data sheets for each material. The properties listed are characterized by a specific value. This assumes (but does not prove) that there is no direction dependence of the properties. However, dental enamel has direction-dependent properties which additionally vary with location in the tooth. The aim of this paper is to show the local direction dependence of physical properties like the elastic modulus or the thermal expansion in dental hard tissues. With this knowledge the 'perfect filling/dental material' could be characterized. Enamel sections of ∼400-500 μm thickness have been cut with a diamond saw from labial/buccal to palatal/lingual (canine, premolar and molar) and parallel to labial (incisor). Crystallite arrangements have been measured in over 400 data points on all types of teeth with x-ray scattering techniques, known from materials science. X-ray scattering measurements show impressively that dental enamel has a strong direction dependence of its physical properties which also varies with location within the tooth. Dental materials possess only little or no property direction dependence. Therefore, a mismatch was found between enamel and dental materials properties. Since dental materials should possess equal (direction depending) properties, worthwhile properties could be characterized by transferring the directional properties of enamel into a property 'wish list' which future dental materials should fulfil. Hereby the 'perfect dental material' can be characterized.

  1. Viscoelastic Properties of Human Tracheal Tissues.

    Science.gov (United States)

    Safshekan, Farzaneh; Tafazzoli-Shadpour, Mohammad; Abdouss, Majid; Shadmehr, Mohammad B

    2017-01-01

    The physiological performance of trachea is highly dependent on its mechanical behavior, and therefore, the mechanical properties of its components. Mechanical characterization of trachea is key to succeed in new treatments such as tissue engineering, which requires the utilization of scaffolds which are mechanically compatible with the native human trachea. In this study, after isolating human trachea samples from brain-dead cases and proper storage, we assessed the viscoelastic properties of tracheal cartilage, smooth muscle, and connective tissue based on stress relaxation tests (at 5% and 10% strains for cartilage and 20%, 30%, and 40% for smooth muscle and connective tissue). After investigation of viscoelastic linearity, constitutive models including Prony series for linear viscoelasticity and quasi-linear viscoelastic, modified superposition, and Schapery models for nonlinear viscoelasticity were fitted to the experimental data to find the best model for each tissue. We also investigated the effect of age on the viscoelastic behavior of tracheal tissues. Based on the results, all three tissues exhibited a (nonsignificant) decrease in relaxation rate with increasing the strain, indicating viscoelastic nonlinearity which was most evident for cartilage and with the least effect for connective tissue. The three-term Prony model was selected for describing the linear viscoelasticity. Among different models, the modified superposition model was best able to capture the relaxation behavior of the three tracheal components. We observed a general (but not significant) stiffening of tracheal cartilage and connective tissue with aging. No change in the stress relaxation percentage with aging was observed. The results of this study may be useful in the design and fabrication of tracheal tissue engineering scaffolds.

  2. Inkjet printing of viable human dental follicle stem cells

    Directory of Open Access Journals (Sweden)

    Mau Robert

    2015-09-01

    Full Text Available Inkjet printing technology has the potential to be used for seeding of viable cells for tissue engineering approaches. For this reason, a piezoelectrically actuated, drop-on-demand inkjet printing system was applied to deliver viable human dental follicle stem cells (hDFSC of sizes of about 15 μm up to 20 μm in diameter. The purpose of these investigations was to verify the stability of the printing process and to evaluate cell viability post printing. Using a Nanoplotter 2.1 (Gesim, Germany equipped with the piezoelectric printhead NanoTip HV (Gesim, Germany, a concentration of 6.6 ×106 cells ml−1 in DMEM with 10% fetal calf serum (FCS could be dispensed. The piezoelectric printhead has a nominal droplet volume of ~ 400 pl and was set to a voltage of 75 V and a pulse of 50 μs while dosing 50 000 droplets over a time of 100 seconds. The volume and trajectory of the droplet were checked by a stroboscope test right before and after the printing process. It was found that the droplet volume decreases significantly by 35% during printing process, while the trajectory of the droplets remains stable with only an insignificant number of degrees deviation from the vertical line. It is highly probable that some cell sedimentations or agglomerations affect the printing performance. The cell viability post printing was assessed by using the Trypan Blue dye exclusion test. The printing process was found to have no significant influence on cell survival. In conclusion, drop-on-demand inkjet printing can be a potent tool for the seeding of viable cells.

  3. Equine Dental Pulp Connective Tissue Particles Reduced Lameness in Horses in a Controlled Clinical Trial.

    Science.gov (United States)

    Bertone, Alicia L; Reisbig, Nathalie A; Kilborne, Allison H; Kaido, Mari; Salmanzadeh, Navid; Lovasz, Rebecca; Sizemore, Joy L; Scheuermann, Logan; Kopp, Rosalind J; Zekas, Lisa J; Brokken, Matthew T

    2017-01-01

    To assess if injection of allogeneic dental pulp tissue particles would improve lameness in horses with naturally occurring osteoarthritis (OA) or soft tissue (ST) injury. Prospective, randomized, blinded, and controlled clinical trial and client survey assessment. Forty lame client-owned horses. Sterile dental pulp, recovered from otherwise healthy foals that perish during dystocia, was processed under good manufacturing processing to produce mechanically manipulated, unexpanded pulp tissue particles containing viable cells surrounded in extracellular matrix. Forty lame client-owned horses with confirmed OA (n = 20), or ST injury (desmitis or tendonitis) received a 2 mL intra-articular (n = 20 OA) or intra-lesional (n = 20) injection of control transport vehicle (n = 20) or 10 × 10(6) dental pulp tissue particles (n = 20). Acclimatized horses had baseline measurements performed and were then injected on day 0. Horses were treadmill exercised for 2 weeks, evaluated by clinical parameters, lameness score, edema (score and circumference), pain on flexion (OA) or pressure (ST), and clients' scores for pain and discomfort before and through 45 days after pulp injection. Twenty horses were available for >2.5-year follow-up. Pulp-treated horses showed decrease in lameness compared to baseline (P 2.5-year follow-up, at least 10 horses were in work. Dental pulp tissue particles can be considered as a treatment option for equine lameness due to OA, desmitis, or tendonitis.

  4. Pulp Cell Tracking by Radionuclide Imaging for Dental Tissue Engineering

    Science.gov (United States)

    Souron, Jean-Baptiste; Petiet, Anne; Decup, Franck; Tran, Xuan Vinh; Lesieur, Julie; Poliard, Anne; Le Guludec, Dominique; Letourneur, Didier; Chaussain, Catherine; Rouzet, Francois

    2014-01-01

    Pulp engineering with dental mesenchymal stem cells is a promising therapy for injured teeth. An important point is to determine the fate of implanted cells in the pulp over time and particularly during the early phase following implantation. Indeed, the potential engraftment of the implanted cells in other organs has to be assessed, in particular, to evaluate the risk of inducing ectopic mineralization. In this study, our aim was to follow by nuclear imaging the radiolabeled pulp cells after implantation in the rat emptied pulp chamber. For that purpose, indium-111-oxine (111In-oxine)-labeled rat pulp cells were added to polymerizing type I collagen hydrogel to obtain a pulp equivalent. This scaffold was implanted in the emptied pulp chamber space in the upper first rat molar. Labeled cells were then tracked during 3 weeks by helical single-photon emission computed tomography (SPECT)/computed tomography performed on a dual modality dedicated small animal camera. Negative controls were performed using lysed radiolabeled cells obtained in a hypotonic solution. In vitro data indicated that 111In-oxine labeling did not affect cell viability and proliferation. In vivo experiments allowed a noninvasive longitudinal follow-up of implanted living cells for at least 3 weeks and indicated that SPECT signal intensity was related to implanted cell integrity. Notably, there was no detectable systemic release of implanted cells from the tooth. In addition, histological analysis of the samples showed mitotically active fibroblastic cells as well as neoangiogenesis and nervous fibers in pulp equivalents seeded with entire cells, whereas pulp equivalents prepared from lysed cells were devoid of cell colonization. In conclusion, our study demonstrates that efficient labeling of pulp cells can be achieved and, for the first time, that these cells can be followed up after implantation in the tooth by nuclear imaging. Furthermore, it appears that grafted cells retained the label and

  5. Hydroxyapatite and Carbonated Apatite as Models for the Dissolution Behavior of Human Dental Enamel

    National Research Council Canada - National Science Library

    Budz, J.A; Lore, M; Nancollas, G.H

    1987-01-01

    ... to understand the mechanism of dental caries. In the present study, kinetic comparisons of the dissolution of hydroxyapatite, carbonated apatite, and ground human dental enamel have been made in order that the appropriateness of these synthetic...

  6. The effect of gastric juice on the development of erosive changes in hard dental tissue

    Directory of Open Access Journals (Sweden)

    Stojšin Ivana

    2014-01-01

    Full Text Available Introduction. Gastroesophageal reflux disease (GERD is an esophageal disorder where the refluxed gastric contents enters first into the esophagus followed by the pharynx, oral cavity, larynx, airway and middle ear, causing a range of disorders and symptoms. Hydrochloric acid from the gastric contents is responsible for the demineralization of dental hard tissues and release of matrix metalloproteinase from the dentin. Objective. The aim of this study was to verify the SEM (scanning electron microscopy analysis of the surface enamel, the enamel-dentin border and dentine after the exposure of intact teeth to filtrate of gastric contents obtained during routine endoscopy. Methods. Material used in the research was 10 extracted human impacted third molars. The coronal part of the tooth was divided into two parts, and then the two halves of teeth were exposed to the filtrate of gastric juice obtained during routine gastroscopy, which had been frozen until the moment of the experiment initiation. All samples of teeth were immersed in the filtrate of the content at a temperature of 20°C for 60 minutes. The prepared samples were observed by the SEM in the area of the enamel, the enamel-dentin border and in the area of dentin at different magnification. Results. The SEM analysis showed that both enamel and dentin had a significant demineralization of these tissues. Enamel surface resembled a demineralization similar to that of acid conditioning before the application of composite restorations. The degree of mineralization was more intense towards the enamel - dentin border, and at this area the enamel prisms were not fully recognizable. The dentin had a complete loss of peritubular dentin, the entry points of the dentin tubules were expanded and intertubular dentin demineralization was also registered. Conclusion. SEM analysis showed a significant degree of destruction of enamel and dentin. Significant changes in the surface structure of enamel and

  7. An overview of the use of lasers in general dental practice: 1. Laser physics and tissue interactions.

    Science.gov (United States)

    Sulieman, Munther

    2005-05-01

    High tech dentistry now involves the routine use of lasers in general dental practice for various procedures once thought only possible with the conventional dental drill or scalpel. In 1990, the first dental laser, the dLase 300 (American Dental Lasers, Corpus Christi,TX 78405 USA), was introduced to the profession. There are now many different types of laser used in dentistry using a variety of wavelengths. Each laser wavelength is absorbed differently by soft and hard tissues and the efficiency of the laser has been determined by the ability of the tissue to absorb or reflect that wavelength. This and the following article hope to give a broad overview of dental lasers and their clinical uses. This article gives an overview of the relevant laser physics and highlights the laser-tissue interactions.

  8. Gentamicin concentrations in human subcutaneous tissue

    DEFF Research Database (Denmark)

    Lorentzen, Hanne; Kallehave, Finn Lasse; Kolmos, Hans Jørn Jepsen

    1996-01-01

    in human subcutaneous adipose tissue by a microdialysis technique. Seven healthy young volunteers each had four microdialysis probes placed in the fat (subcutaneous) layer of the abdominal skin. After the administration of a 240-mg gentamicin intravenous bolus, consecutive measurements of the drug...

  9. A First Step in De Novo Synthesis of a Living Pulp Tissue Replacement Using Dental Pulp MSCs and Tissue Growth Factors, Encapsulated within a Bioinspired Alginate Hydrogel.

    Science.gov (United States)

    Bhoj, Manasi; Zhang, Chengfei; Green, David W

    2015-07-01

    A living, self-supporting pulp tissue replacement in vitro and for transplantation is an attractive yet unmet bioengineering challenge. Our aim is to create 3-dimensional alginate-based microenvironments that replicate the shape of gutta-percha and comprise key elements for the proliferation of progenitor cells and the release of growth factors. An RGD-bearing alginate framework was used to encapsulate dental pulp stem cells and human umbilical vein endothelial cells in a ratio of 1:1. The alginate hydrogel also retained and delivered 2 key growth factors, vascular endothelial growth factor-121 and fibroblast growth factor, in a sufficient amount to induce proliferation. A method was then devised to replicate the shape of gutta-percha using RGD alginate within a custom-made mold of thermoresponsive N-isopropylacrylamide. Plugs of alginate containing different permutations of growth factor-based encapsulates were tested and evaluated for viability, proliferation, and release kinetics between 1 and 14 days. According to scanning electron microscopic and confocal microscopic observations, the encapsulated human endothelial cells and dental pulp stem cell distribution were frequent and extensive throughout the length of the construct. There were also high levels of viability in all test environments. Furthermore, cell proliferation was higher in the growth factor-based groups. Growth factor release kinetics also showed significant differences between them. Interestingly, the combination of vascular endothelial growth factor and fibroblast growth factor synergize to significantly up-regulate cell proliferation. RGD-alginate scaffolds can be fabricated into shapes to fill the pulp space by simple templating. The addition of dual growth factors to cocultures of stem cells within RGD-alginate scaffolds led to the creation of microenvironments that significantly enhance the proliferation of dental pulp stem cell/human umbilical vein endothelial cell combinations. Copyright

  10. Distribution of biglycan and decorin in rat dental tissue

    Directory of Open Access Journals (Sweden)

    Tenório D.M.H.

    2003-01-01

    Full Text Available Biglycan and decorin are small leucine-rich proteoglycans that play several biological and structural roles in different tissues and organs. Several reports have indicated that biglycan participates in odontoblast and ameloblast differentiation and in the calcification process. In the present study we show that the expression of biglycan changes from within the ameloblasts and odontoblasts to the extracellular space according to the stage of animal development. In predentin and in the pulp space, however, biglycan was continually expressed throughout the period of investigation. In contrast, decorin was absent in odontoblasts and in ameloblasts and was exclusively expressed in predentin throughout the period of observation. In young rats, however, decorin was expressed in the extracellular spaces of the pulp, where it was concentrated mainly in the peripheral pulp.

  11. [Experimental study of dental implants with nanostructured non-resorbable coating integration into bone tissue].

    Science.gov (United States)

    Grigor'ian, A S; Khamraev, T K; Toporkova, A K; Amirov, A R

    2010-01-01

    In 2 dogs on both sides of mandible premolars were removed. In 3 months after dental alveolus healing intraosseous screwdriver dental implants (Konmet, Russia) were installed in the place of the removed teeth. Analogous operation was done on the contralateral side: the same type of implants were installed but with new nanostructured multifunctional biocompatible non-resorbable coating (MBNC) of the Ti-Ca-P-C-O-N composition. The animals were taken out of the experiment in 4 months after implants installation and implant-bone blocks were studied by SEM-method. According to the SEM-data in the region of the contact of implant-bone without new MBNC only fibrous connective tissue was formed. In case when MBNC was used the close welding of bone tissue with implant surface was observed that was considered as sign of osteointegration.

  12. Flapless dental implant surgery may improve hard and soft tissue outcomes.

    Science.gov (United States)

    Oliver, Richard

    2011-12-01

    A 1-year prospective clinical study of soft tissue conditions and marginal bone changes around dental implants after flapless implant surgery. Jeong S-M, Choi B-H, Kim J, Xuan F, Lee D-H, Mo DY, et al. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011;111:41-6. Richard Oliver, BDS, BSc, PhD, FDSRCPS, FDS(OS)RCPS PURPOSE/QUESTION: To evaluate the soft tissue and marginal bone levels after 1 year around dental implants placed using flapless surgery Korea Science and Engineering Foundation (KOSEF) funded by the Korean Government Case series Level 3: Other evidence Grade C: Consensus, disease-oriented evidence, usual practice, expert opinion, or case series for studies of diagnosis, treatment, prevention, or screening. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Histological observation on dental hard tissue irradiated by ultrashort-pulsed laser

    Science.gov (United States)

    Uchizono, Takeyuki; Awazu, Kunio; Igarashi, Akihiro; Kato, Junji; Hirai, Yoshito

    2006-04-01

    In the field of dentistry, effectiveness of USPL irradiation is researched because USPL has less thermal side effect to dental hard tissue. In this paper, we observed morphological change and optical change of dental hard tissue irradiated by USPL for discussing the safety and effectiveness of USPL irradiation to dental hard tissues. Irradiated samples were crown enamel and root dentin of bovine teeth. Lasers were Ti:sapphire laser, which had pulse duration (P d)of 130 fsec and pulse repetition rate (f) of 1kHz and wavelength (l) of 800nm, free electron laser (FEL), which had P d of 15 μsec and f of 10Hz and wavelength of 9.6μm, and Er:YAG laser, which had P d of 250 μsec and f of 10Hz and wavelength of 2.94μm. After laser irradiation, the sample surfaces and cross sections were examined with SEM and EDX. The optical change of samples was observed using FTIR. In SEM, the samples irradiated by USPL had sharp and accurate ablation with no crack and no carbonization. But, in FEL and Er:YAG laser, the samples has rough ablation with crack and carbonization. It was cleared that the P/Ca ratio of samples irradiated by USPL had same value as non-irradiated samples. There was no change in the IR absorption spectrum between samples irradiated by USPL and non-irradiated sample. But, they of samples irradiated by FEL and Er:YAG laser, however, had difference value as non-irradiated samples. These results showed that USPL might be effective to ablate dental hard tissue without thermal damage.

  14. Long-term outcomes of soft tissue augmentation around dental implants on soft and hard tissue stability: a systematic review.

    Science.gov (United States)

    Rotundo, Roberto; Pagliaro, Umberto; Bendinelli, Elena; Esposito, Marco; Buti, Jacopo

    2015-09-01

    To investigate whether the height and volume of the soft tissues and peri-implant bone levels around dental implants are stable, when soft tissue augmentation has been performed. Three operators conducted a search on electronic databases (MEDLINE, COCHRANE, EMBASE) and a hand searching on the main journals dealing with periodontology and implantology until 30 October 2014. Only articles that considered peri-implant soft tissue augmentation performed in a group of at least 10 patients and with a follow-up of at least 1 year were selected. The outcome variables were peri-implant attached/keratinized tissue width (KTW) changes, peri-implant marginal soft tissue level (PSL) changes, and peri-implant marginal bone level (PBL) changes. The review was performed according to the PRISMA statements. Ten articles were selected for the qualitative synthesis, but only one meta-analysis was accomplished, indicating that 1 year after implant recession coverage procedures, a mean gain of 1.65 ± 0.01 mm (90% CrI [1.44; 1.85]) was observed. There is no long-term evidence whether augmented soft tissues can be maintained over time and able to influence the peri-implant bone levels. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Putative Stem Cells in Human Dental Pulp with Irreversible Pulpitis-An Exploratory Study

    Science.gov (United States)

    Wang, Z.; Pan, J.; Wright, JT; Bencharit, S.; Zhang, S.; Everett, ET; Teixeira, FB; Preisser, JS

    2010-01-01

    Introduction Although human dental pulp stem cells isolated from healthy teeth have been extensively characterized, it is unknown whether stem cells also exist in clinically compromised teeth with irreversible pulpitis. Here we explored whether cells retrieved from clinically compromised dental pulp have stem cell-like properties. Methods Pulp cells were isolated from healthy teeth (control group) and from teeth with clinically diagnosed irreversible pulpitis (diseased group). Cell proliferation, stem cell marker STRO-1 expression and cell odonto-osteo-genic differentiation competence were compared. Results Cells from the diseased group demonstrated decreased colony formation capacity and a slightly decreased cell proliferation rate but had similar STRO-1 expression, and exhibited a similar percentage of positive ex vivo osteogenic induction and dentin sialophosphoprotein expression from STRO-1-enriched pulp cells. Conclusion Our study provides preliminary evidence that clinically compromised dental pulp may contain putative cells with certain stem cell properties. Further characterization of these cells will provide insight regarding whether they could serve as a source of endogenous multipotent cells in tissue regeneration based dental pulp therapy. PMID:20416426

  16. Successful isolation, in vitro expansion and characterization of stem cells from Human Dental Pulp

    Directory of Open Access Journals (Sweden)

    Preethy SP

    2010-01-01

    Full Text Available BACKGROUND: Recent studies have shown that mesenchymal stem cells isolated from post natal human dental pulp, (Dental pulp stem cells-DPSCs which is from permanent teeth and SHED (stem cells from human exfoliated deciduous teeth,the Periodontal ligament stem cells (PDLSC and Stem cells from root Apical papilla(SCAPhave the potential to differentiate into cells of a variety of tissues including heart, muscle, cartilage, bone, nerve, salivary glands, teeth etc(1,2,3,4.This multipotential ability of DPSCs is being researched for clinical application for treating a variety of diseases like myocardial infarction, muscular dystrophy, neuro-degenerative disorders, cartilage replacement, tooth regeneration and for repair of bone defects to mention a few. Moreover, the isolation of stem cells from teeth is minimally invasive, readily accessible and the non immunogenic characteristic of dental stem cells has paved the way for efforts to store the exfoliated deciduous teeth or milk teeth which is usually discarded, for use in the future. In this study we have isolated and expanded in vitro, the cells obtained from human dental pulp. MATERIALS AND METHODS: After obtaining written informed consent, 24 teeth that were extracted for therapeutic or cosmetic reasons from 16 patients were used in this study. The specimens were transported from the clinic to NCRM lab taking 6 to 48 Hrs. For removal of the pulp tissue, the teeth were split obliquely at the Cementoenamel junction and the pulp tissue was isolated using brooches. The extracted pulp tissues were subjected to digestion using Collagenase type-I and type II at 37˚C for 15- 30 minutes. The digested cells were filtered with 70µm filter and centrifuged at 1800 rpm for 10 minutes. The pellet was then suspended in Dulbecco’s modified Eagle’s medium (DMEM/Ham’s F12 supplemented with 15% fetal bovine serum , 100 U/ml penicillin, 100 µg/ml streptomycin,2 m M L -glutamine, and 2 m M nonessential amino

  17. Dental Practice, Human Immunodeficiency Virus Transmission and ...

    African Journals Online (AJOL)

    The acquired immune deficiency syndrome (AIDS) is a major cause of death in Africa today and it is estimated that 80% of the over 40 million people living with human immunodeficiency virus (HIV)/AIDS (PLWHA) world-wide are residing in sub-Saharan countries.[1] In Nigeria, AIDS was first reported in 1986 following the ...

  18. Dental Practice, Human Immunodeficiency Virus Transmission and ...

    African Journals Online (AJOL)

    Background: More than 40 oral manifestations of human immunodeficiency virus (HIV) infection have been recorded and between 70% and 90% of persons with HIV infection will have at least one oral manifestation at some time during the course of their disease. Oral health-care workers (OHCWs) are therefore, key players ...

  19. Dental hard tissue ablation using mid-infrared tunable nanosecond pulsed Cr:CdSe laser.

    Science.gov (United States)

    Lin, Taichen; Aoki, Akira; Saito, Norihito; Yumoto, Masaki; Nakajima, Sadahiro; Nagasaka, Keigo; Ichinose, Shizuko; Mizutani, Koji; Wada, Satoshi; Izumi, Yuichi

    2016-12-01

    Mid-infrared erbium: yttrium-aluminum-garnet (Er:YAG) and erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) lasers (2.94- and 2.78-μm, respectively) are utilized for effective dental hard tissue treatment because of their high absorption in water, hydroxide ion, or both. Recently, a mid-infrared tunable, nanosecond pulsed, all-solid-state chromium-doped: cadmium-selenide (Cr:CdSe) laser system was developed, which enables laser oscillation in the broad spectral range around 2.9 μm. The purpose of this study was to evaluate the ablation of dental hard tissue by the nanosecond pulsed Cr:CdSe laser at a wavelength range of 2.76-3.00 μm. Enamel, dentin, and cementum tissue were irradiated at a spot or line at a fluence of 0-11.20 J/cm(2) /pulse (energy output: 0-2.00 mJ/pulse) with a repetition rate of 10 Hz and beam diameter of ∼150 μm on the target (pulse width ∼250 ns). After irradiation, morphological changes, ablation threshold, depth, and efficiency, and thickness of the structurally and thermally affected layer of irradiated surfaces were analyzed using stereomicroscopy, scanning electron microscopy (SEM), and light microscopy of non-decalcified histological sections. The nanosecond pulsed irradiation without water spray effectively ablated dental hard tissue with no visible thermal damage such as carbonization. The SEM analysis revealed characteristic micro-irregularities without major melting and cracks in the lased tissue. The ablation threshold of dentin was the lowest at 2.76 μm and the highest at 3.00 μm. The histological analysis revealed minimal thermal and structural changes ∼20 μm wide on the irradiated dentin surfaces with no significant differences between wavelengths. The efficiency of dentin ablation gradually increased from 3.00 to 2.76 μm, at which point the highest ablation efficiency was observed. The nanosecond pulsed Cr:CdSe laser demonstrated an effective ablation ability of hard dental

  20. Mineralized polycaprolactone nanofibrous matrix for odontogenesis of human dental pulp cells.

    Science.gov (United States)

    Kim, Jong-Jin; Bae, Won-Jung; Kim, Joung-Mok; Kim, Jung-Ju; Lee, Eun-Jung; Kim, Hae-Won; Kim, Eun-Cheol

    2014-03-01

    The aim of the present study was to fabricate mineralized polycaprolactone nanofibrous scaffold and investigate its ability to elicit odontogenic differentiation of human dental pulp cells, compared to the pure polycaprolactone scaffold. Polycaprolactone nanofibrous scaffold was produced by electrospinning, and the surface was mineralized with apatite. Cellular behaviors on the mineralized polycaprolactone scaffold were assessed in terms of cell adhesion, growth, and odontoblastic differentiation. To evaluate the signal transduction of human dental pulp cells, mRNA expression was analyzed and Western blotting was performed. Mineralized polycaprolactone showed improved cell proliferation, mineralized nodule formation, and expression of odontoblastic marker genes including alkaline phosphatase, osteopontin, osteocalcin, dentin sialophosphoprotein (DSPP), and dentin matrix protein-1, as compared with pure polycaprolactone. Although the cell adhesion on the mineralized polycaprolactone was similar to that of the polycaprolactone, the expression level of proteins including collagen type I and the key adhesion receptor (integrin components α1, α2, and β1) was upregulated in mineralized polycaprolactone compared to polycaprolactone. Especially, cells seeded onto mineralized polycaprolactone scaffolds showed significantly increased levels of phosphorylated focal adhesion kinase, a marker of integrin activation, and downstream pathways, such as phosphor (p)-Akt, p-extracellular signal regulated kinase, p-c Jun N-terminal kinase, nuclear factor-kappa B, c-fos, and c-jun, compared with pure polycaprolactone. The mineralized polycaprolactone scaffold is attractive for dentin tissue engineering by promoting growth and odontogenic differentiation of human dental pulp cells through the integrin-mediated signaling pathway.

  1. Cyclic GMP phosphodiesterase activity role in normal and inflamed human dental pulp.

    Science.gov (United States)

    Spoto, G; Ferrante, M; D'Intino, M; Rega, L; Dolci, M; Trentini, P; Ciavarelli, L

    2004-01-01

    Cyclic GMP phosphodiesterase (cGMP PDE) plays an important role in pulp tissues. High levels of cGMP PDE are found in dental pulp cells. In the present study cGMP PDE activity was analyzed in normal healthy human dental pulps, in reversible pulpitis and in irreversible pulpitis. Enzymatic cGMP PDE control values for normal healthy pulps were 4.74+/-0.32 nmol/mg of proteins. In reversible pulpitis the cGMP PDE activity increased almost 3 times. In irreversible pulpitis specimens the values increased 4.5 times compared with the normal healthy pulps activity. The differences between the groups (control vs. reversible pulpitis and vs. irreversible pulpitis) were statistically significant. These results point to a role of cGMP PDE in the initial pulp response after injury.

  2. Cyclic Amp phosphodiesterase activity in normal and inflamed human dental pulp.

    Science.gov (United States)

    Spoto, G; Menna, V; Serra, E; Santoleri, F; Perfetti, G; Ciavarelli, L; Trentini, P

    2004-01-01

    Cyclic AMP phosphodiesterase (cAMP PDE) seems to be important in pulp tissues. High levels of cAMP PDE have been demonstrated to be in dental pulp cells. In the present study cAMP PDE activity was analyzed in normal healthy human dental pulps, in reversible pulpitis and in irreversible pulpitis. Enzymatic cAMP PDE control values for normal healthy pulps were 12.14 +/- 3.74 nmols/mg of proteins. In reversible pulpitis the cAMP PDE activity increased almost 2.5 times. In irreversible pulpitis specimens the values increased 4.5 times compared with normal healthy pulps activity. The differences between the groups (control vs. reversible pulpitis and vs. irreversible pulpitis) were statistically significant. These results could point to a role of cAMP PDE in the initial pulp response after injury.

  3. Beta adrenergic receptors in human cavernous tissue

    Energy Technology Data Exchange (ETDEWEB)

    Dhabuwala, C.B.; Ramakrishna, C.V.; Anderson, G.F.

    1985-04-01

    Beta adrenergic receptor binding was performed with /sup 125/I iodocyanopindolol on human cavernous tissue membrane fractions from normal tissue and transsexual procedures obtained postoperatively, as well as from postmortem sources. Isotherm binding studies on normal fresh tissues indicated that the receptor density was 9.1 fmoles/mg. with a KD of 23 pM. Tissue stored at room temperature for 4 to 6 hours, then at 4C in saline solution for 19 to 20 hours before freezing showed no significant changes in receptor density or affinity, and provided evidence for the stability of postmortem tissue obtained within the same time period. Beta receptor density of 2 cavernous preparations from transsexual procedures was not significantly different from normal control tissues, and showed that high concentrations of estrogen received by these patients had no effect on beta adrenergic receptor density. Displacement of /sup 125/iodocyanopindolol by 5 beta adrenergic agents demonstrated that 1-propranolol had the greatest affinity followed by ICI 118,551, zinterol, metoprolol and practolol. When the results of these displacement studies were subjected to Scatfit, non- linear regression line analysis, a single binding site was described. Based on the relative potency of the selective beta adrenergic agents it appears that these receptors were of the beta 2 subtype.

  4. Absorption of infrared radiation by human dental hard substances

    Science.gov (United States)

    Roth, Klaus K.; Duczynski, Edwin W.; von der Heide, Hans-Joachim; Struve, Bert

    1993-12-01

    Absorption spectra of enamel, dentin, synthetic hydroxyapatite and deionized water were taken in the wavelength band 500 to 3000 nm. It could be shown that infrared radiation is mainly absorbed in the aqueous components of dental hard tissues. Because of their decreased water content extinctions measured are slightly lower than those of deionized water. Furthermore, mineral absorptions could be detected in the range of 2760 to 2840 nm with a maximum at 2800 nm in enamel and a smaller one at 2500 nm in dentin.

  5. Hard dental tissue minimal-invasive preparation using contemporary polymer rotating instruments and laser

    Directory of Open Access Journals (Sweden)

    Beloica Miloš

    2014-01-01

    Full Text Available Goal of contemporary dentistry is to decrease the patient’s discomfort during treatment. Dentists aim to achieve maximum with the newly developed dental materials as well as with new cavity preparation techniques in the shortest time span. Since the development of the first constructed borer (drilling machine for caries removal, the preparation techniques have considerably changed. The progress of dental materials as well as the cavity preparation techniques has led us to contemporary carbide tungsten and diamond borers that are used with obligatory water cooling. The innovation within this field represents newly developed polymer borers that can detect the difference between carious lesions and healthy tooth structure. In this way the cavity preparation may be performed without damaging dental healthy tissue. This is possible owing to their hardness which is lower than the hardness of intact dentin. Polymer borer preparation is painless with less vibration, while the increase in temperature is negligible. Lasers have been used in clinical dentistry since 1980s so it can be said that they represent a new technology. The function of lasers is based on ablation which requires water. Erbium lasers have shown the highest potential with their ability to produce effective ablation of hard dental tissues. Laser application in dentistry requires special training as well as some protective measures. Laser advantages, compared to traditional preparation techniques, involve the absence of vibration, painless preparation, possibility of preparation without anesthetic and easier patient’s adjustment to dental intervention which is of importance, especially in pediatric dentistry. [Projekat Ministarstva nauke Republike Srbije, br. 46009

  6. Effects of high-mobility group box 1 on the proliferation and odontoblastic differentiation of human dental pulp cells.

    Science.gov (United States)

    Qi, S C; Cui, C; Yan, Y H; Sun, G H; Zhu, S R

    2013-12-01

    To investigate the expression of high-mobility group box 1 (HMGB1) in human dental pulp tissues and the effects of HMGB1 on proliferation and odontoblastic differentiation of human dental pulp cells (hDPCs). Immunohistochemical assay, immunofluorescence staining and flow cytometric analysis were used to detect the expression of HMGB1 in the human dental pulp and hDPCs, respectively. The proliferation of hDPCs was examined by CCK-8 after culturing human primary hDPCs in the presence of HMGB1 with different doses. Odontoblastic differentiation of hDPCs was determined using alkaline phosphatase (ALPase) activity assay and mineralized nodule formation. Important mineralization-related genes such as ALP, dental sialophosphoprotein (DSPP) and dental matrix protein-1 (DMP-1) were determined by real-time polymerase chain reaction. Western blot analysis was performed to determine the difference in expressions of DMP-1 and DSP with or without the presence of exogenous HMGB1. Simultaneously, messenger RNA and protein levels of HMGB1 and RAGE were also detected. The protein level of HMGB1 in the supernatants was quantified using ELISA analysis. HMGB1 was found in human dental pulp tissue and in the nuclei of hDPCs. During hDPC odontoblastic differentiation, HMGB1 translocated from the nuclei to the cytoplasm and then secreted out from hDPCs. Exogenous HMGB1 promoted hDPC proliferation and mineralized nodule formation. It up-regulated the activity of ALPase and the mRNA and protein levels of dentine matrix protein-1 (DMP-1), alkaline phosphatase (ALP), dentine sialophosphoprotein (DSPP) and receptor for advance glycation end (RAGE) of hDPCs. HMGB1 promoted the proliferation and odontoblastic differentiation of hDPCs. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  7. Measurements of erbium laser-ablation efficiency in hard dental tissues under different water cooling conditions.

    Science.gov (United States)

    Kuščer, Lovro; Diaci, Janez

    2013-10-01

    Laser triangulation measurements of Er:YAG and Er,Cr:YSGG laser-ablated volumes in hard dental tissues are made, in order to verify the possible existence of a "hydrokinetic" effect that has been proposed as an alternative to the "subsurface water expansion" mechanism for hard-tissue laser ablation. No evidence of the hydrokinetic effect could be observed under a broad range of tested laser parameters and water cooling conditions. On the contrary, the application of water spray during laser exposure of hard dental material is observed to diminish the laser-ablation efficiency (AE) in comparison with laser exposure under the absence of water spray. Our findings are in agreement with the generally accepted principle of action for erbium laser ablation, which is based on fast subsurface expansion of laser-heated water trapped within the interstitial structure of hard dental tissues. Our measurements also show that the well-known phenomenon of ablation stalling, during a series of consecutive laser pulses, can primarily be attributed to the blocking of laser light by the loosely bound and recondensed desiccated minerals that collect on the tooth surface during and following laser ablation. In addition to the prevention of tooth bulk temperature buildup, a positive function of the water spray that is typically used with erbium dental lasers is to rehydrate these minerals, and thus sustaining the subsurface expansion ablation process. A negative side effect of using a continuous water spray is that the AE gets reduced due to the laser light being partially absorbed in the water-spray particles above the tooth and in the collected water pool on the tooth surface. Finally, no evidence of the influence of the water absorption shift on the hypothesized increase in the AE of the Er,Cr:YSGG wavelength is observed.

  8. The application of lesion sterilization and tissue repair 3Mix-MP for treating rat's dental pulp tissue

    Directory of Open Access Journals (Sweden)

    Raditya Nugroho

    2015-03-01

    Full Text Available Background: Lesion sterilization and tissue repair (LSTR 3Mix-MP are three broad-spectrum antibiotics, including metronidazole, ciprofloxacin and minocycline are mixed with propylene glycol or macrogol. There is the possibility ofthe healing process that marked proliferation ofnew blood vessels and proliferation offibroblasts in the treatment ofirreversible pulpitis by pulp capping LSTR 3MixMP because of  the principle of the method LSTR 3Mix-MP is to kill bacteria. Purpose: The purpose of this study to prove the effect of LSTR 3Mix-MP on chronic inflammation and the healing process in rat dental pulp tissue in vivo. Methods: Rattus norvegicus anaesthetized by using ketamine and xylazine dissolved in sterile isotonic saline solution (0.2 ml/50gr mm on the upper right thigh. Cavity preparation class I to perforation by using a low speed tapered diamond round bur. In the treatment group, rats were treated 3Mix-MP at a dose of10 mg and then covered with glass ionomer cement for 7 days on the pulp that has been opened for 3 days. The control group treated with saline irrigation on the pulp that has been opened for 3 days. Rats were killed after seven days, and then made preparations pulp tissue to count the number oflymphocytes, macrophages, plasma cells, blood vessels, and fibroblasts Results: There is an increase in the average number ofmacrophage cells, plasma, and fibroblasts; and decreased lymphocytes and blood vessels in the treated group exposure LSTR 3Mix-MP. Conclusion:LSTR 3Mix-MP can reduce chronic inflammation process and enhance the healing process in rat dental pulp tissue.

  9. Regenerative dentistry: Current and future perspectives to rejuvenate and reclaim dental tissues

    Directory of Open Access Journals (Sweden)

    Sourabh Jagannath Torvi

    2014-01-01

    Full Text Available While widespread advances have occurred in all details of science over the past decade, regenerative dentistry has also seen its part of breakthrough innovations. Tooth regeneration offers new and innovative approaches to common problems encountered in oral and dental sciences. In cases where a tooth is lost, it may be replaced with an implant, bridge, or a denture capable of mastication. However, in many developing countries, it is often simpler (and far more cost-effective to remove the tooth. Strategies based upon regenerative medicine that facilitates the repair or replacement of damaged teeth may hold particular promise as a means to reduce the cost of dental care. Dental maladies aside, the tooth is also a compelling candidate as a template for organogenesis which could have far-reaching implications for the field of regenerative medicine. [1] A systematic review of the literature was performed using various internet-based search engines (PubMed, Medline Plus, Cochrane, Medknow, Ebsco, Science Direct, Hinari, WebMD, IndMed, and Embase using keywords such as "dental pulp stem cells," "regeneration," "medical applications," and "tissue engineering." This review explores existing and visionary approaches in the revolutionary field of regenerative dentistry, as an extension to the familiar concepts of regenerative medicine.

  10. Human serum promotes osteogenic differentiation of human dental pulp stem cells in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Alessandra Pisciotta

    Full Text Available Human dental pulp is a promising alternative source of stem cells for cell-based tissue engineering in regenerative medicine, for the easily recruitment with low invasivity for the patient and for the self-renewal and differentiation potential of cells. So far, in vitro culture of mesenchymal stem cells is usually based on supplementing culture and differentiation media with foetal calf serum (FCS. FCS is known to contain a great quantity of growth factors, and thus to promote cell attachment on plastic surface as well as expansion and differentiation. Nevertheless, FCS as an animal origin supplement may represent a potential means for disease transmission besides leading to a xenogenic immune response. Therefore, a significant interest is focused on investigating alternative supplements, in order to obtain a sufficient cell number for clinical application, avoiding the inconvenients of FCS use. In our study we have demonstrated that human serum (HS is a suitable alternative to FCS, indeed its addition to culture medium induces a high hDPSCs proliferation rate and improves the in vitro osteogenic differentiation. Furthermore, hDPSCs-collagen constructs, pre-differentiated with HS-medium in vitro for 10 days, when implanted in immunocompromised rats, are able to restore critical size parietal bone defects. Therefore these data indicate that HS is a valid substitute for FCS to culture and differentiate in vitro hDPSCs in order to obtain a successful bone regeneration in vivo.

  11. Catechins inhibit vascular endothelial growth factor production and cyclooxygenase-2 expression in human dental pulp cells.

    Science.gov (United States)

    Nakanishi, T; Mukai, K; Hosokawa, Y; Takegawa, D; Matsuo, T

    2015-03-01

    To investigate the effect of catechins on vascular endothelial growth factor (VEGF) production and cyclooxygenase-2 (COX-2) expression in human dental pulp cells (HDPC) stimulated with bacteria-derived factors or pro-inflammatory cytokines. Morphologically fibroblastic cells established from explant cultures of healthy human dental pulp tissues were used as HDPC. HDPC pre-treated with catechins, epigallocatechin-3-gallate (EGCG) or epicatechin gallate (ECG), were exposed to lipopolysaccharide (LPS), peptidoglycan (PG), interlukin-1β (IL-1β) or tumour necrosis factor-α (TNF-α). VEGF production was examined by enzyme-linked immunosorbent assay, and COX-2 expression was assessed by immunoblot. EGCG and ECG significantly reduced LPS- or PG-mediated VEGF production in the HDPC in a dose-dependent manner. EGCG also prevented IL-1β-mediated VEGF production. Although TNF-α did not enhance VEGF production in the dental pulp cells, treatment of 20 μg mL(-1) of EGCG decreased the level of VEGF. In addition, the catechins attenuated COX-2 expression induced by LPS and IL-1β. The up-regulated VEGF and COX-2 expressions in the HDPC stimulated with these bacteria-derived factors or IL-1β were diminished by the treatment of EGCG and ECG. These findings suggest that the catechins may be beneficial as an anti-inflammatory tool of the treatment for pulpal inflammation. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  12. Atomic-scale compositional mapping reveals Mg-rich amorphous calcium phosphate in human dental enamel.

    Science.gov (United States)

    La Fontaine, Alexandre; Zavgorodniy, Alexander; Liu, Howgwei; Zheng, Rongkun; Swain, Michael; Cairney, Julie

    2016-09-01

    Human dental enamel, the hardest tissue in the body, plays a vital role in protecting teeth from wear as a result of daily grinding and chewing as well as from chemical attack. It is well established that the mechanical strength and fatigue resistance of dental enamel are derived from its hierarchical structure, which consists of periodically arranged bundles of hydroxyapatite (HAP) nanowires. However, we do not yet have a full understanding of the in vivo HAP crystallization process that leads to this structure. Mg(2+) ions, which are present in many biological systems, regulate HAP crystallization by stabilizing its precursor, amorphous calcium phosphate (ACP), but their atomic-scale distribution within HAP is unknown. We use atom probe tomography to provide the first direct observations of an intergranular Mg-rich ACP phase between the HAP nanowires in mature human dental enamel. We also observe Mg-rich elongated precipitates and pockets of organic material among the HAP nanowires. These observations support the postclassical theory of amelogenesis (that is, enamel formation) and suggest that decay occurs via dissolution of the intergranular phase. This information is also useful for the development of more accurate models to describe the mechanical behavior of teeth.

  13. Immunomic Screening of Cell Surface Molecules on Undifferentiated Human Dental Pulp Stem Cells.

    Science.gov (United States)

    Hwang, Hyo-In; Lee, Tae-Hyung; Kang, Kyung-Jung; Ryu, Chun-Jeih; Jang, Young-Joo

    2015-08-15

    Human adult dental pulp tissue is a source of adult stem cells that have a potential to differentiate into various tissues, although the primary cell suspensions cultured from pulp tissue are mixtures of both stem cell and nonstem cell populations with heterogeneous phenotypes and various differentiation efficiencies. Therefore, cell surface protein markers on dental pulp stem cells are critical for detection and purification of stem cell populations. Yet, little is known about the cell surface molecules that are specifically associated with the undifferentiated and progenitor state of human adult dental pulp stem cells (hDPSCs). Presently, cell surface proteins expressed on hDPSCs were assessed by screening surface molecules specifically expressed on dentinogenic progenitors. Using a decoy immunization strategy, a set of monoclonal antibodies (MAbs) was generated against undifferentiated pulp progenitor cells. Forty-five hybridomas produced MAbs that interacted weakly, if at all, to differentiated pulp cells. Of these, 19 MAbs (18 IgG, 1 IgM) recognized surface molecules on undifferentiated hDPSCs. By multicolor flow cytometric analysis, 40%-60% of newly identified MAb-positive cells were demonstrated to be positive for the CD44 and CD90 mesenchymal markers. When MAb-positive cells were sorted from the heterogeneous pulp cell suspension, mineralization efficiency was increased three to five times compared with MAb-negative cells. The results suggest that the decoy immunization is an efficient method for isolation of MAbs against dentinogenic progenitors. These MAbs will be helpful for identification and enrichment of hDPSCs for efficient dentin regeneration.

  14. Dental Pulp Stem Cells as a multifaceted tool for bioengineering and the regeneration of craniomaxillofacial tissues

    Directory of Open Access Journals (Sweden)

    Maitane eAurrekoetxea

    2015-10-01

    Full Text Available Dental pulp stem cells, or DPSC, are neural crest-derived cells with an outstanding capacity to differentiate along multiple cell lineages of interest for cell therapy. In particular, highly efficient osteo/dentinogenic differentiation of DPSC can be achieved using simple in vitro protocols, making these cells a very attractive and promising tool for the future treatment of dental and periodontal diseases. Among craniomaxillofacial organs, the tooth and salivary gland are two such cases in which complete regeneration by tissue engineering using DPSC appears to be possible, as research over the last decade has made substantial progress in experimental models of partial or total regeneration of both organs, by cell recombination technology. Moreover, DPSC seem to be a particularly good choice for the regeneration of nerve tissues, including injured or transected cranial nerves. In this context, the oral cavity appears to be an excellent testing ground for new regenerative therapies using DPSC. However, many issues and challenges need yet to be addressed before these cells can be employed in clinical therapy. In this review, we point out some important aspects on the biology of DPSC with regard to their use for the reconstruction of different craniomaxillofacial tissues and organs, with special emphasis on cranial bones, nerves, teeth, and salivary glands. We suggest new ideas and strategies to fully exploit the capacities of DPSC for bioengineering of the aforementioned tissues.

  15. Light-microscopical investigation of the distribution of extracellular matrix molecules and calcifications in human dental pulps of various ages.

    Science.gov (United States)

    Hillmann, G; Geurtsen, W

    1997-07-01

    The distribution of extracellular matrix molecules, especially collagen types I, III, V, and VI, in the extracellular matrix of the connective tissue of human dental pulp of various ages was studied by polarization and indirect immunofluorescence microscopy by using a conventional fluorescence microscope and a confocal laser scanning microscope. Polarization and immunofluorescence microscopy of paraffin sections showed thick fibers of collagen type I, which represented the main component of the connective tissue matrix of the dental pulp. By indirect immunofluorescence, thin fibers and small bundles of collagen type III were determined to be one of the main fibrillar elements present in the dental pulp matrix. Collagen type IV was detected by a clear intense staining of the basement membrane of blood vessels at all ages examined. Collagens type V and VI formed a dense meshwork of thin microfibrils throughout the stroma of the connective tissue of the dental pulp. These fibers were localized around blood vessels and appeared to be enriched in the subodontoblastic layer. Investigations by means of confocal laser scanning microscopy revealed fibers of collagen type VI spiralling between fully differentiated odontoblasts toward the predentin layer. With advancing age, the connective tissue matrix appeared to be condensed and aggregates of thick fiber bundles could be observed. Furthermore, the participation of various collagen types in the composition of pulp stones was shown. These calcifications and diffuse calcifications increased in frequency with advancing age in a statistically significant manner.

  16. Staining plastic blocks with triiodide to image cells and soft tissues in backscattered electron SEM of skeletal and dental tissues.

    Science.gov (United States)

    Boyde, A

    2012-07-24

    Backscattered electron scanning electron microscopy (BSE SEM) is an invaluable method for studying the histology of the hard, mineralised components of poly-methyl methacrylate (PMMA) or other resin embedded skeletal and dental tissues. Intact tissues are studied in micro-milled or polished block faces with an electron-optical section thickness of the order of a half to one micron and with the area of the section as big as a whole--large or small--bone organ. However, BSE SEM does not give information concerning the distribution of uncalcified, 'soft', cellular and extracellular matrix components. This can be obtained by confocal microscopy of the same block and the two sorts of images merged but the blocks have to be studied in two microscope systems. The present work shows a new, simple and economic approach to visualising both components by using the triiodide ion in Lugol's iodine solution to stain the block surface prior to the application of any conductive coating--and the latter can be omitted if charging is suppressed by use of poor vacuum conditions in the SEM sample chamber. The method permits the use of archival tissue, and it will be valuable in studies of both normal growth and development and pathological changes in bones and joints, including osteoporosis and osteoarthritis, and tissue adaptation to implants.

  17. Marginal tissue response adjacent to Astra Dental Implants supporting overdentures in the mandible

    DEFF Research Database (Denmark)

    Gotfredsen, K; Holm, B; Sewerin, I

    1993-01-01

    The aim of this study was to evaluate the marginal tissue response adjacent to implant supported overdentures. Twenty edentulous patients had 2 Astra Dental Implants placed in the canine region of the lower jaw. New overdentures were retained by individual ball attachments in 11 patients...... that two osseointegrated Astra Dental Implants could successfully retain an overdenture in the lower jaw. However, long-term observation is needed for a definitive evaluation of this treatment concept....... showed any periodontal signs of failure. At the 2-year examination, no pocket depths adjacent to the implants exceeded 4 mm and no bone loss exceeded 3 mm. The mean annual bone loss was less than 0.2 mm during the first 2 years. The preliminary results from this limited study were promising and showed...

  18. Mechanical characterization of human brain tissue.

    Science.gov (United States)

    Budday, S; Sommer, G; Birkl, C; Langkammer, C; Haybaeck, J; Kohnert, J; Bauer, M; Paulsen, F; Steinmann, P; Kuhl, E; Holzapfel, G A

    2017-01-15

    Mechanics are increasingly recognized to play an important role in modulating brain form and function. Computational simulations are a powerful tool to predict the mechanical behavior of the human brain in health and disease. The success of these simulations depends critically on the underlying constitutive model and on the reliable identification of its material parameters. Thus, there is an urgent need to thoroughly characterize the mechanical behavior of brain tissue and to identify mathematical models that capture the tissue response under arbitrary loading conditions. However, most constitutive models have only been calibrated for a single loading mode. Here, we perform a sequence of multiple loading modes on the same human brain specimen - simple shear in two orthogonal directions, compression, and tension - and characterize the loading-mode specific regional and directional behavior. We complement these three individual tests by combined multiaxial compression/tension-shear tests and discuss effects of conditioning and hysteresis. To explore to which extent the macrostructural response is a result of the underlying microstructural architecture, we supplement our biomechanical tests with diffusion tensor imaging and histology. We show that the heterogeneous microstructure leads to a regional but not directional dependence of the mechanical properties. Our experiments confirm that human brain tissue is nonlinear and viscoelastic, with a pronounced compression-tension asymmetry. Using our measurements, we compare the performance of five common constitutive models, neo-Hookean, Mooney-Rivlin, Demiray, Gent, and Ogden, and show that only the isotropic modified one-term Ogden model is capable of representing the hyperelastic behavior under combined shear, compression, and tension loadings: with a shear modulus of 0.4-1.4kPa and a negative nonlinearity parameter it captures the compression-tension asymmetry and the increase in shear stress under superimposed

  19. Effect of different calcium phosphate scaffold ratios on odontogenic differentiation of human dental pulp cells.

    Science.gov (United States)

    AbdulQader, Sarah Talib; Kannan, Thirumulu Ponnuraj; Rahman, Ismail Ab; Ismail, Hanafi; Mahmood, Zuliani

    2015-04-01

    Calcium phosphate (CaP) scaffolds have been widely and successfully used with osteoblast cells for bone tissue regeneration. However, it is necessary to investigate the effects of these scaffolds on odontoblast cells' proliferation and differentiation for dentin tissue regeneration. In this study, three different hydroxyapatite (HA) to beta tricalcium phosphate (β-TCP) ratios of biphasic calcium phosphate (BCP) scaffolds, BCP20, BCP50, and BCP80, with a mean pore size of 300μm and 65% porosity were prepared from phosphoric acid (H2PO4) and calcium carbonate (CaCO3) sintered at 1000°C for 2h. The extracts of these scaffolds were assessed with regard to cell viability and differentiation of odontoblasts. The high alkalinity, more calcium, and phosphate ions released that were exhibited by BCP20 decreased the viability of human dental pulp cells (HDPCs) as compared to BCP50 and BCP80. However, the cells cultured with BCP20 extract expressed high alkaline phosphatase activity and high expression level of bone sialoprotein (BSP), dental matrix protein-1 (DMP-1), and dentin sialophosphoprotein (DSPP) genes as compared to that cultured with BCP50 and BCP80 extracts. The results highlighted the effect of different scaffold ratios on the cell microenvironment and demonstrated that BCP20 scaffold can support HDPC differentiation for dentin tissue regeneration. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Tissue-based map of the human proteome

    DEFF Research Database (Denmark)

    Uhlén, Mathias; Fagerberg, Linn; Hallström, Björn M.

    2015-01-01

    Resolving the molecular details of proteome variation in the different tissues and organs of the human body will greatly increase our knowledge of human biology and disease. Here, we present a map of the human tissue proteome based on an integrated omics approach that involves quantitative...... transcriptomics at the tissue and organ level, combined with tissue microarray-based immunohistochemistry, to achieve spatial localization of proteins down to the single-cell level. Our tissue-based analysis detected more than 90% of the putative protein-coding genes. We used this approach to explore the human......, in all major tissues and organs in the human body....

  1. Impact of dental implant insertion method on the peri-implant bone tissue: Experimental study

    Directory of Open Access Journals (Sweden)

    Stamatović Novak

    2013-01-01

    Full Text Available Background/Aim. The function of dental implants depends on their stability in bone tissue over extended period of time, i.e. on osseointegration. The process through which osseointegration is achieved depends on several factors, surgical insertion method being one of them. The aim of this study was to histopathologically compare the impact of the surgical method of implant insertion on the peri-implant bone tissue. Methods. The experiment was performed on 9 dogs. Eight weeks following the extraction of lower premolars implants were inserted using the one-stage method on the right mandibular side and two-stage method on the left side. Three months after implantation the animals were sacrificed. Three distinct regions of bone tissue were histopathologically analyzed, the results were scored and compared. Results. In the specimens of one-stage implants increased amount of collagen fibers was found in 5 specimens where tissue necrosis was also observed. Only moderate osteoblastic activity was found in 3 sections. The analysis of bone-to-implant contact region revealed statistically significantly better results regarding the amount of collagen tissue fibers for the implants inserted in the two-stage method (Wa = 59 105, α = 0.05. No necrosis and osteoblastic activity were observed. Conclusion. Better results were achieved by the two-stage method in bone-to-implant contact region regarding the amount of collagen tissue, while the results were identical regarding the osteoblastic activity and bone tissue necrosis. There was no difference between the methods in the bone-implant interface region. In the bone tissue adjacent to the implant the results were identical regarding the amount of collagen tissue, osteoblastic reaction and bone tissue necrosis, while better results were achieved by the two-stage method regarding the number of osteocytes.

  2. WNT5A inhibits human dental papilla cell proliferation and migration

    Energy Technology Data Exchange (ETDEWEB)

    Peng, L. [West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan (China); State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, Sichuan (China); Ye, L.; Dong, G.; Ren, L.B.; Wang, C.L.; Xu, P. [West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan (China); Zhou, X.D., E-mail: pl_huaxi@yahoo.com.cn [West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan (China); State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, Sichuan (China)

    2009-12-18

    WNT proteins are a large family of cysteine-rich secreted molecules that are linked to both canonical and non-canonical signal pathways, and have been implicated in oncogenesis and tissue development. Canonical WNT proteins have been proven to play critical roles in tooth development, while little is known about the role of non-canonical WNT proteins such as WNT5A. In this study, WNT5A was localized to human dental papilla tissue and human dental papilla cells (HDPCs) cultured in vitro, using immunochemistry and RT-PCR. Recombinant adenovirus encoding full-length Wnt5a cDNA was constructed to investigate the biological role of WNT5A on HDPCs. The BrdU incorporation assay, the MTT assay and flow cytometric analysis showed that over-expression of Wnt5a strongly inhibited the proliferation of HDPCs in vitro. Wound healing and transwell migration assays indicated that over-expression of WNT5A reduced migration of HDPCs. In conclusion, our results showed that WNT5A negatively regulates both proliferation and migration of HDPCs, suggesting its important role in odontogenesis via controlling the HDPCs.

  3. Multipotent Differentiation of Human Dental Pulp Stem Cells: a Literature Review.

    Science.gov (United States)

    Nuti, N; Corallo, C; Chan, B M F; Ferrari, M; Gerami-Naini, B

    2016-10-01

    The advent of regenerative medicine has brought us the opportunity to regenerate, modify and restore human organs function. Stem cells, a key resource in regenerative medicine, are defined as clonogenic, self-renewing, progenitor cells that can generate into one or more specialized cell types. Stem cells have been classified into three main groups: embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs) and adult/postnatal stem cells (ASCs). The present review focused the attention on ASCs, which have been identified in many perioral tissues such as dental pulp, periodontal ligament, follicle, gingival, alveolar bone and papilla. Human dental pulp stem cells (hDPSCs) are ectodermal-derived stem cells, originating from migrating neural crest cells and possess mesenchymal stem cell properties. During last decade, hDPSCs have received extensive attention in the field of tissue engineering and regenerative medicine due to their accessibility and ability to differentiate in several cell phenotypes. In this review, we have carefully described the potential of hDPSCs to differentiate into odontoblasts, osteocytes/osteoblasts, adipocytes, chondrocytes and neural cells.

  4. The effects of human platelet lysate on dental pulp stem cells derived from impacted human third molars.

    Science.gov (United States)

    Chen, Bo; Sun, Hai-Hua; Wang, Han-Guo; Kong, Hui; Chen, Fa-Ming; Yu, Qing

    2012-07-01

    Human platelet lysate (PL) has been suggested as a substitute for fetal bovine serum (FBS) in the large-scale expansion of dental pulp stem cells (DPSCs). However, the biological effects and the optimal concentrations of PL for the proliferation and differentiation of human DPSCs remain unexplored. We isolated and expanded stem cells from the dental pulp of extracted third molars and evaluated the effects of PL on the cells' proliferative capacity and differentiation potential in vitro and in vivo. Before testing, immunocytochemical staining and flow cytometry-based cell sorting showed that the cells derived from human dental pulp contained mesenchymal stem cell populations. Cells were grown on tissue culture plastic or on hydroxyapatite-tricalcium phosphate (HA/TCP) biomaterials and were incubated with either normal or odontogenic/osteogenic media in the presence or absence of various concentrations of human PL for further investigation. The proliferation of DPSCs was significantly increased when the cells were cultured in 5% PL under all testing conditions (P models. We conclude that the appropriate concentration of PL enhances the proliferation and mineralized differentiation of human DPSCs both in vitro and in vivo, which supports the use of PL as an alternative to FBS or a nonzoonotic adjuvant for cell culture in future clinical trials. However, the elucidation of the molecular complexity of PL products and the identification of both the essential growth factors that determine the fate of a specific stem cell and the criteria to establish dosing require further investigation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Direct Spectrometry: A New Alternative for Measuring the Fluorescence of Composite Resins and Dental Tissues

    OpenAIRE

    Silva, T. M. da [UNESP; Oliveira, H. P. M. de; SEVERINO, D.; Balducci, I. [UNESP; Huhtala, M. F. R. L. [UNESP; Goncalves, S. E. P. [UNESP

    2014-01-01

    The aim of this study was to evaluate the fluorescence intensity of different composite resins and compare those values with the fluorescence intensity of dental tissues. Different composite resins were used to make 10 discs (2 mm in depth and 4 mm in diameter) of each brand, divided into groups: 1) Z (Filtek Z350, 3M ESPE), 2) ES (Esthet-X, Dentsply), 3) A (Amelogen Plus, Ultradent), 4) DVS (Durafill-VS, Heraeus Kulzer) with 2 mm composite resin for enamel (A2), 5) OES ([Esthet-X] opaque-OA ...

  6. Soft tissue removal by maceration and feeding of Dermestes sp.: impact on morphological and biomolecular analyses of dental tissues in forensic medicine.

    Science.gov (United States)

    Offele, Daniel; Harbeck, Michaela; Dobberstein, Reimer C; von Wurmb-Schwark, Nicole; Ritz-Timme, Stefanie

    2007-09-01

    Maceration techniques remove soft tissue by the destruction of biomolecules, but the applied techniques may also affect the morphology and the molecular integrity of the hard tissue itself. The impact of seven different techniques for soft tissue removal on morphological and biomolecular parameters of teeth and dental tissues was systematically examined. All methods tested showed significant changes in dental morphology and in the molecular integrity of DNA and the dental proteins, as revealed by aspartic acid racemisation (AAR). In forensic casework this may have severe impacts on the results of morphological methods (e.g. age estimation based on root translucency) and of biomolecular analyses (e.g. age estimation based on AAR and DNA analysis). Therefore, age estimation based on AAR should not be applied to tissue treated in such a manner, and it is recommended that teeth for analysis should be extracted before soft tissue removal. DNA in the hard tissue seems to be less susceptible to soft tissue removal than proteins, and several of the tested maceration techniques appear not to have a damaging effect on DNA. Generally, the indication for soft tissue removal demands a careful case management to avoid methodological collisions.

  7. Investigation of dental pulp stem cells isolated from discarded human teeth extracted due to aggressive periodontitis.

    Science.gov (United States)

    Sun, Hai-Hua; Chen, Bo; Zhu, Qing-Lin; Kong, Hui; Li, Qi-Hong; Gao, Li-Na; Xiao, Min; Chen, Fa-Ming; Yu, Qing

    2014-11-01

    Recently, human dental pulp stem cells (DPSCs) isolated from inflamed dental pulp tissue have been demonstrated to retain some of their pluripotency and regenerative potential. However, the effects of periodontal inflammation due to periodontitis and its progression on the properties of DPSCs within periodontally compromised teeth remain unknown. In this study, DPSCs were isolated from discarded human teeth that were extracted due to aggressive periodontitis (AgP) and divided into three experimental groups (Groups A, B and C) based on the degree of inflammation-induced bone resorption approaching the apex of the tooth root before tooth extraction. DPSCs derived from impacted or non-functional third molars of matched patients were used as a control. Mesenchymal stem cell (MSC)-like characteristics, including colony-forming ability, proliferation, cell cycle, cell surface antigens, multi-lineage differentiation capability and in vivo tissue regeneration potential, were all evaluated in a patient-matched comparison. It was found that STRO-1- and CD146-positive DPSCs can be isolated from human teeth, even in very severe cases of AgP. Periodontal inflammation and its progression had an obvious impact on the characteristics of DPSCs isolated from periodontally affected teeth. Although all the isolated DPSCs in Groups A, B and C showed decreased colony-forming ability and proliferation rate (P cells did not necessarily show significantly diminished in vitro multi-differentiation potential. Only DPSCs from Group A and the Control group formed dentin-like matrix in vivo when cell-seeded biomaterials were transplanted directly into an ectopic transplantation model. However, when cell-seeded scaffolds were placed in the root fragments of human teeth, all the cells formed significant dentin- and pulp-like tissues. The ability of DPSCs to generate dental tissues decreased when the cells were isolated from periodontally compromised teeth (P stem cells with certain MSC properties

  8. Sensory Neuropeptides and Endogenous Opioids Expression in Human Dental Pulp with Asymptomatic Inflammation: In Vivo Study

    Directory of Open Access Journals (Sweden)

    Daniel Chavarria-Bolaños

    2015-01-01

    Full Text Available Purpose. This study quantified the expression of substance P (SP, calcitonin gene-related peptide (CGRP, β-endorphins (β-End, and methionine-enkephalin (Met-Enk in human dental pulp following orthodontic intrusion. Methods. Eight patients were selected according to preestablished inclusion criteria. From each patient, two premolars (indicated for extraction due to orthodontic reasons were randomly assigned to two different groups: the asymptomatic inflammation group (EXPg, which would undergo controlled intrusive force for seven days, and the control group (CTRg, which was used to determine the basal levels of each substance. Once extracted, dental pulp tissue was prepared to determine the expression levels of both neuropeptides and endogenous opioids by radioimmunoassay (RIA. Results. All samples from the CTRg exhibited basal levels of both neuropeptides and endogenous opioids. By day seven, all patients were asymptomatic, even when all orthodontic-intrusive devices were still active. In the EXPg, the SP and CGRP exhibited statistically significant different levels. Although none of the endogenous opioids showed statistically significant differences, they all expressed increasing trends in the EXPg. Conclusions. SP and CGRP were identified in dental pulp after seven days of controlled orthodontic intrusion movement, even in the absence of pain.

  9. Oral bacterial extracts facilitate early osteogenic/dentinogenic differentiation in human dental pulp-derived cells.

    Science.gov (United States)

    Abe, Shu; Imaizumi, Mari; Mikami, Yoshikazu; Wada, Yoshiyuki; Tsuchiya, Shuhei; Irie, Seiko; Suzuki, Shinnosuke; Satomura, Kazuhito; Ishihara, Kazuyuki; Honda, Masaki J

    2010-01-01

    Bacterial metabolites demineralize dental hard tissues, and soluble factors lead to tertiary dentinogenesis in the area of the dentin-pulp complex. However, it is unclear whether the oral bacteria are directly involved in the differentiation of dental pulp cells. In this study, we evaluated the effect of oral bacterial extracts on cellular differentiation in human dental pulp-derived cells (hDPC). The hDPC were obtained from third molar teeth, and the cells were subcultured. The sonicated extracts were obtained from Porphyromonas gingivalis (gram-negative) and Streptococcus mutans (gram-positive). The effect of bacterial extracts on cellular growth and differentiation in hDPC were tested. Alkaline phosphatase activity and bone sialoprotein (BSP) gene expression were increased in hDPC exposed to low concentrations of both sonicated extracts, whereas the activity was decreased upon exposure to high concentrations of sonicated extracts from P. gingivalis. This is the first evidence that oral bacteria have a positive effect on cellular differentiation in hPDC. Copyright 2010 Mosby, Inc. All rights reserved.

  10. Role of STRO-1 sorting of porcine dental germ stem cells in dental stem cell-mediated bone tissue engineering.

    Science.gov (United States)

    Gurel Pekozer, Gorke; Ramazanoglu, Mustafa; Schlegel, Karl Andreas; Kok, Fatma Nese; Torun Kose, Gamze

    2017-05-31

    Stem cells of dental origin emerged as a new source for the regeneration of tissues with advantages mainly including non-invasive collection procedures and lack of ethical contraversies with their harvest or use. In this study, porcine TGSCs (pTGSCs) were isolated from mandibular third molar tooth germs of 6-month-old domestic pigs. This is the first study that reports the isolation and characterization of TGSCs from porcine third molars and their differentiation depending on STRO-1 expression. PTGSCs were sorted according to their STRO-1 expression as STRO-1(+) and STRO-1(-). Sorted and unsorted heterogenous cells (US) were characterized by their osteogenic, chondrogenic and adipogenic differentiation capabilities. STRO-1(+) cells exhibited a higher proliferation rate owing to their clonogenic properties. All three groups of cells were found differentiated into osteogenic lineage as shown by ALP activity, calcium deposition assay, detection of osteogenic mRNAs and, proteins and mineralization staining. According to differentiation analysis, STRO-1(+) cells did not show a better performance for osteogenesis compared to STRO-1(-) and US cells. This might indicate that STRO-1(+) cells might require a heterogeneous population of cells including STRO-1(-) in their niche to perform their proposed role in osteogenesis.

  11. Mercury exposure in the work place and human health: dental amalgam use in dentistry at dental teaching institutions and private dental clinics in selected cities of Pakistan.

    Science.gov (United States)

    Khwaja, Mahmood A; Nawaz, Sadaf; Ali, Saeed Waqar

    2016-03-01

    During the past two decades, mercury has come under increasing scrutiny with regard to its safety both in the general population and in occupationally exposed groups. It's a growing issue of global concern because of its adverse environmental and health impacts. Very few investigations on mercury amalgam use in the dentistry sector have been carried out in South Asia and there is little data reported on mercury contamination of indoor/outdoor air at dental sites. According to an earlier SDPI study, reported in 2013, alarmingly high mercury levels were observed in air (indoor as well as outdoor) at 11 of the 34 visited dental sites (17 dental teaching institutions, 7 general hospitals & 10 dental clinics) in five main cities of Pakistan. 88% of the sites indicated indoor mercury levels in air above the USA EPA reference level of 300 ng/m3. According to our study, carried out at 38 dental teaching institutions in 12 main cities (in Khyber Pakhtunkhwa, Punjab and Sindh provinces) of Pakistan, respondents were of the opinion that the currently offered BDS curriculum does not effectively guide outgoing dental professionals and does not provide them adequate knowledge and training about mercury/mercury amalgam and other mercury related human health and mercury waste issues. 90% of respondents supported the review and revision of the present dental curriculum offered at dental teaching institutions in the country, at the earliest. A study has also been conducted to assess the status of mercury amalgam use in private dental clinics in Gilgit, Hunza, Peshawar, Rawalpindi and Islamabad. More than 90 private dental clinics were visited and dental professionals/private clinics in-charge were interviewed during June-July, 2015. The focus areas of the study were Hg amalgam toxicity, its waste management practices and safety measures practiced among the dental practitioners. In the light of the findings described and discussed in this brief report, to safeguard public health and

  12. Meloxicam medication reduces orthodontically induced dental root resorption and tooth movement velocity: a combined in vivo and in vitro study of dental-periodontal cells and tissue.

    Science.gov (United States)

    Kirschneck, Christian; Meier, Matthias; Bauer, Kathrin; Proff, Peter; Fanghänel, Jochen

    2017-04-01

    Non-steroidal anti-inflammatory drugs (NSAID) are used to alleviate pain sensations during orthodontic therapy but are also assumed to interfere with associated pseudo-inflammatory reactions. In particular, the effects of partially selective COX-2 inhibition over the constitutively expressed COX-1 (11:1) on periodontal cells and tissue, as induced by the NSAID meloxicam, remain unclear. We investigate possible adverse side-effects and potentially useful beneficial effects during orthodontic therapy and examine underlying cellular and tissue reactions. We randomly assigned 63 male Fischer344 rats to three consecutive experiments of 21 animals each (cone-beam computed tomography; histology/serology; reverse-transcription quantitative real-time polymerase chain reaction) in three experimental groups (n = 7; control; orthodontic tooth movement [OTM] of the first/second upper left molars [NiTi coil spring, 0.25 N]; OTM with a daily oral meloxicam dose of 3 mg/kg). In vitro, we stimulated human periodontal ligament fibroblasts (hPDL) with orthodontic pressure (2 g/cm2) with/without meloxicam (10 μM). In vivo, meloxicam significantly reduced serum C-reactive protein concentration, tooth movement velocity, orthodontically induced dentine root resorption (OIRR), osteoclast activity and the relative expression of inflammatory/osteoclast marker genes within the dental-periodontal tissue, while presenting good gastric tolerance. In vitro, we observed a corresponding significant decrease of prostaglandin E2/interleukin-6/RANKL(-OPG) expression and of hPDL-mediated osteoclastogenesis. By inhibiting prostaglandin synthesis, meloxicam seems to downregulate hPDL-mediated inflammation, RANKL-induced osteoclastogenesis and, consequently, tooth movement velocity by about 50%, thus limiting its suitability for analgesia during orthodontic therapy. However, its protective effects regarding OIRR and good tolerance profile suggest future prophylactic application, which merits its

  13. Hard tissue regeneration capacity of apical pulp derived cells (APDCs) from human tooth with immature apex.

    Science.gov (United States)

    Abe, Shigehiro; Yamaguchi, Satoshi; Watanabe, Akihiko; Hamada, Keiichi; Amagasa, Teruo

    2008-06-20

    Recent studies indicate that dental pulp is a new source of adult stem cells. The human tooth with an immature apex is a developing organ, and the apical pulp of this tooth may contain a variety of progenitor/stem cells, which participate in root formation. We investigated the hard tissue regeneration potential of apical pulp derived cells (APDCs) from human tooth with an immature apex. APDCs cultured with a mineralization-promoting medium showed alkaline phosphatase activity in porous hydroxyapatite (HA) scaffolds. The composites of APDCs and HA were implanted subcutaneously in immunocompromised rats and harvested at 12 weeks after implantation. In histological analysis, the APDCs/HA composites exhibited bone- and dentine-like mineralized tissues in the pore areas of HA. This study suggests that the human tooth with an immature apex is an effective source of cells for hard tissue regeneration.

  14. Rat dental pulp tissue reaction after capped with propolis derived nonflavonoid extract

    Directory of Open Access Journals (Sweden)

    Ardo Sabir

    2011-03-01

    Full Text Available Propolis is a resinous material collected by honey bees from various plants. Many types of research have shown that it has antibacterial and anti-inflammation activities. Flavonoid is the main chemical substance in propolis that inhibits bacterial growth and reduces the release of free radicals, suggesting that this component has anti-bacterial and anti-inflammatory properties. However, there is another chemical substance in propolis that shows antibacterial dan anti-inflammatory activities. The purpose of the present study was to assess the rat dental pulp tissue reaction after capped with propolis derived non-flavonoids extract. Non-flavonoids substances were purified from an ethanol extract of propolis obtained from South Sulawesi, Indonesia. A Class I cavity was prepared on the occlusal surface of the right maxillary first molar in Spraque-Dawley rats. The dental pulp was exposed and then capped with a zinc oxide-based filler as a control (Group I, or non-flavonoids propolis (Group II. Then, each cavity was filled with glass ionomer cement. The animals were sacrificed at week 1, 2, or 4. Biopsy samples were obtained, and these were stained and viewed by light microscopy. The histological examination was based on the presence of polymorph nuclear leukocytes and macrophages. The results showed that pulp inflammation occurred in both groups as early as week 1. However, the inflammation occurred in Group II was relatively milder compared to Group I at all time period. Therefore, present results suggest that application of non-flavonoids propolis extract on rat's dental pulp tissue might inhibit inflammatory process.

  15. Aspects on dental hard tissues in primary teeth from patients with Ehlers-Danlos syndrome.

    Science.gov (United States)

    Klingberg, Gunilla; Hagberg, Catharina; Norén, Jörgen G; Nietzsche, Sandor

    2009-07-01

    Ehlers-Danlos syndrome (EDS) is a rare hereditary condition affecting connective tissues and dental hard tissues. Primary enamel and dentine from EDS patients were expected to differ from those of healthy subjects regarding morphology and chemical composition. Forty-seven exfoliated primary teeth from 25 patients with EDS were investigated. Morphology was studied using a polarized light microscope, scanning electron microscope, and X-ray microanalysis. Comparisons were made with 36 primary teeth from 36 healthy patients. Morphological analysis of enamel in EDS teeth showed a high frequency of postnatally hypomineralized enamel and postnatally located incremental lines, whereas dentine was normal in all patients. Chemical analysis could not reveal any differences between EDS and control patients except for lower content of C and a higher Ca/P ratio in the enamel in the EDS teeth, indicating porous enamel. Regarding dentine, EDS teeth had a lower content of C, and a higher content of Ca, P, and O. Ratios for Ca/C and Ca/O were also higher compared with controls. There are several aberrations of booth enamel and dentine in primary teeth from patients with EDS. These could explain the occurrence of both more dental caries and tooth fractures in patients with EDS.

  16. [Dental implantation and soft tissue augmentation after ridge preservation in a molar site: a case report].

    Science.gov (United States)

    Zhao, L P; Zhan, Y L; Hu, W J; Wang, H J; Wei, Y P; Zhen, M; Xu, T; Liu, Y S

    2016-12-18

    For ideal implant rehabilitation, an adequate bone volume, optical implant position, and stable and healthy soft tissue are required. The reduction of alveolar bone and changes in its morphology subsequent to tooth extraction will result in insufficient amount of bone and adversely affect the ability to optimally place dental implants in edentulous sites. Preservation of alveolar bone volume through ridge preservation has been demonstrated to reduce the vertical and horizontal contraction of the alveolar bone crest after tooth extraction and reduce the need for additional bone augmentation procedures during implant placement. In this case, a patient presented with a mandible molar of severe periodontal disease, the tooth was removed as atraumatically as possible and the graft material of Bio-Oss was loosely placed in the alveolar socket without condensation and covered with Bio-Gide to reconstruct the defects of the alveolar ridge. Six months later, there were sufficient height and width of the alveolar ridge for the dental implant, avoiding the need of additional bone augmentation and reducing the complexity and unpredictability of the implant surgery. Soft tissue defects, such as gingival and connective tissue, played crucial roles in long-term implant success. Peri-implant plastic surgery facilitated development of healthy peri-implant structure able to withstand occlusal forces and mucogingival stress. Six months after the implant surgery, the keratinized gingiva was absent in the buccal of the implant and the vestibular groove was a little shallow. The free gingival graft technique was used to solve the vestibulum oris groove supersulcus and the absence of keratinized gingiva around the implant. The deepening of vestibular groove and broadening of keratinized gingiva were conducive to the long-term health and stability of the tissue surrounding the implant. Implant installation and prosthetic restoration showed favorable outcome after six months.

  17. Age-related Changes in the Alkaline Phosphatase Activity of Healthy and Inflamed Human Dental Pulp.

    Science.gov (United States)

    Aslantas, Eda E; Buzoglu, Hatice Dogan; Karapinar, Senem Pinar; Cehreli, Zafer C; Muftuoglu, Sevda; Atilla, Pergin; Aksoy, Yasemin

    2016-01-01

    Alkaline phosphatase (ALP) plays an important role in inducing mineralization events in the dental pulp. This study investigated and compared the ALP levels in healthy and inflamed pulp in young and old human pulp. Tissue samples were collected from young (60 years) donors. In both age groups, healthy human pulp (n = 18) were collected from extracted wisdom teeth. For reversible and irreversible pulpitis, pulp samples (n = 18 each) were obtained during endodontic treatment. ALP activity was assessed by spectrophotometry and immunhistochemistry. Regardless of age, reversible pulpitis group samples showed a slight elevation in ALP activity compared with normal healthy pulp. In elderly patients, ALP expression with irreversible pulpitis was significantly higher than those with a healthy pulp (P irreversible pulpitis, only the old pulp shows significantly elevated ALP levels. Such an increase may trigger calcification events, which may eventually cause difficulties in endodontic treatment procedures in elderly individuals. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  18. The reconstruction and analysis of tissue specific human metabolic networks.

    Science.gov (United States)

    Hao, Tong; Ma, Hong-Wu; Zhao, Xue-Ming; Goryanin, Igor

    2012-02-01

    Human tissues have distinct biological functions. Many proteins/enzymes are known to be expressed only in specific tissues and therefore the metabolic networks in various tissues are different. Though high quality global human metabolic networks and metabolic networks for certain tissues such as liver have already been studied, a systematic study of tissue specific metabolic networks for all main tissues is still missing. In this work, we reconstruct the tissue specific metabolic networks for 15 main tissues in human based on the previously reconstructed Edinburgh Human Metabolic Network (EHMN). The tissue information is firstly obtained for enzymes from Human Protein Reference Database (HPRD) and UniprotKB databases and transfers to reactions through the enzyme-reaction relationships in EHMN. As our knowledge of tissue distribution of proteins is still very limited, we replenish the tissue information of the metabolic network based on network connectivity analysis and thorough examination of the literature. Finally, about 80% of proteins and reactions in EHMN are determined to be in at least one of the 15 tissues. To validate the quality of the tissue specific network, the brain specific metabolic network is taken as an example for functional module analysis and the results reveal that the function of the brain metabolic network is closely related with its function as the centre of the human nervous system. The tissue specific human metabolic networks are available at .

  19. CD146 positive human dental pulp stem cells promote regeneration of dentin/pulp-like structures.

    Science.gov (United States)

    Matsui, Mikiko; Kobayashi, Tomoko; Tsutsui, Takeo W

    2018-01-08

    CD146 and STRO-1 are endothelial biomarkers that are co-expressed on the cellular membranes of blood vessels within human dental pulp tissue. This study characterized the percentage of dentin-like structures produced by CD146-positive (CD146+) human dental pulp stem cells (DPSCs), compared with their CD146-negative (CD146-) counterparts. DPSC populations were enriched using magnetic-activated cell sorting (MACS), yielding CD146+ and CD146- cells, as well as mixtures composed of 25% CD146+ cells and 75% CD146- cells (CD146+/-). Cell growth assays indicated that CD146+ cells exhibit an approximate 3-4 h difference in doubling time, compared with CD146- cells. Cell cycle distributions were determined by flow cytometry analysis. The low percentage of CD146+ cells' DNA content in G0/G1 phase were compared with CD146- and non-separated cells. In contrast to CD146- and non-separated cells, prompt mineralization was observed in CD146+ cells. Subsequently, qRT-PCR revealed high mRNA expression of CD146 and Alkaline phosphatase in mineralization-induced CD146+ cells. CD146+ cells were also observed high adipogenic ability by Oil red O staining. Histological examinations revealed an increased area of dentin/pulp-like structures in transplanted CD146+ cells, compared with CD146- and CD146+/- cells. Immunohistochemical studies detected dentin matrix protein-1 (DMP1) and dentin sialophosphoprotein (DSPP), as well as human mitochondria, in transplanted DPSCs. Co-expression of CD146 and GFP indicated that CD146 was expressed in transplanted CD146+ cells. CD146+ cells may promote mineralization and generate dentin/pulp-like structures, suggesting a role in self-renewal of stem cells and dental pulp regenerative therapy.

  20. Success of Maxillary Alveolar Defect Repair in Rats Using Osteoblast-Differentiated Human Deciduous Dental Pulp Stem Cells.

    Science.gov (United States)

    Jahanbin, Arezoo; Rashed, Roozbeh; Alamdari, Daryoush Hamidi; Koohestanian, Niloufar; Ezzati, Atefeh; Kazemian, Mojgan; Saghafi, Shadi; Raisolsadat, Mohammad Ali

    2016-04-01

    The use of cell-based therapies represents one of the most advanced methods for enhancing the regenerative response in craniofacial abnormalities. The main aim of this study was to evaluate the regenerative potential of human dental pulp stem cells, isolated from deciduous teeth, for reconstructing maxillary alveolar defects in Wistar rats. Human deciduous dental pulp stem cells were isolated and stimulated to differentiate into osteoblasts in culture media. Maxillary alveolar defects were created in 60 Wistar rats by a surgical procedure. Then, on the basis of the type of graft used to repair the bone defect, the rats were divided into 6 equal groups: groups 1 and 2, transplantation of iliac bone graft; groups 3 and 4, transplantation of stem cells derived from deciduous dental pulp in addition to collagen matrix; groups 5 and 6, transplantation of just collagen matrix. Then, fetal bone formation, granulation tissue, fibrous tissue, and inflammatory tissue were evaluated by hematoxylin-eosin staining at 1 month (groups 1, 3, and 5) and 2 months (groups 2, 4, and 6) after surgery, and data were analyzed and compared using the Fisher exact test. Maximum fetal bone formation occurred in group 2, in which iliac bone graft was inserted into the defect area for 2 months; there also were significant differences among the groups for bone formation (P = .009). In the 1-month groups, there were no significant differences between the control and stem cell-plus-scaffold groups. There were significant differences between the 2-month groups for fetal bone formation only between the control and scaffold groups (P = .026). The study showed that human dental pulp stem cells are an additional cell resource for repairing maxillary alveolar defects in rats and constitute a promising model for reconstruction of human maxillary alveolar defects in patients with cleft lip and palate. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc

  1. Environmental lead pollution and its possible influence on tooth loss and hard dental tissue lesions

    Directory of Open Access Journals (Sweden)

    Cenić-Milošević Desanka

    2013-01-01

    Full Text Available Bacground/Aim. Environmental lead (Pb pollution is a global problem. Hard dental tissue is capable of accumulating lead and other hard metals from the environment. The aim of this study was to investigate any correlation between the concentration of lead in teeth extracted from inhabitants of Pančevo and Belgrade, Serbia, belonging to different age groups and occurrence of tooth loss, caries and non-carious lesions. Methods. A total of 160 volunteers were chosen consecutively from Pančevo (the experimental group and Belgrade (the control group and divided into 5 age subgroups of 32 subjects each. Clinical examination consisted of caries and hard dental tissue diagnostics. The Decayed Missing Filled Teeth (DMFT Index and Significant Caries Index were calculated. Extracted teeth were freed of any organic residue by UV digestion and subjected to voltammetric analysis for the content of lead. Results. The average DMFT scores in Pančevo (20.41 were higher than in Belgrade (16.52; in the patients aged 31-40 and 41-50 years the difference was significant (p < 0.05 and highly significant in the patients aged 51-60 (23.69 vs 18.5, p < 0.01. Non-carious lesions were diagnosed in 71 (44% patients from Pančevo and 39 (24% patients from Belgrade. The concentrations of Pb in extracted teeth in all the groups from Pančevo were statistically significantly (p < 0.05 higher than in all the groups from Belgrade. In the patients from Pančevo correlations between Pb concentration in extracted teeth and the number of extracted teeth, the number of carious lesions and the number of non-carious lesions showed a statistical significance (p < 0.001, p < 0.01 and p < 0.001, respectively. Conclusion. According to correlations between lead concentration and the number of extracted teeth, number of carious lesions and non-carious lesions found in the patients living in Pančevo, one possible cause of tooth loss and hard dental tissue damage could be a long

  2. Viscoelastic parameter identification of human brain tissue.

    Science.gov (United States)

    Budday, S; Sommer, G; Holzapfel, G A; Steinmann, P; Kuhl, E

    2017-10-01

    Understanding the constitutive behavior of the human brain is critical to interpret the physical environment during neurodevelopment, neurosurgery, and neurodegeneration. A wide variety of constitutive models has been proposed to characterize the brain at different temporal and spatial scales. Yet, their model parameters are typically calibrated with a single loading mode and fail to predict the behavior under arbitrary loading conditions. Here we used a finite viscoelastic Ogden model with six material parameters-an elastic stiffness, two viscoelastic stiffnesses, a nonlinearity parameter, and two viscous time constants-to model the characteristic nonlinearity, conditioning, hysteresis and tension-compression asymmetry of the human brain. We calibrated the model under shear, shear relaxation, compression, compression relaxation, and tension for four different regions of the human brain, the cortex, basal ganglia, corona radiata, and corpus callosum. Strikingly, unconditioned gray matter with 0.36kPa and white matter with 0.35kPa were equally stiff, whereas conditioned gray matter with 0.52kPa was three times stiffer than white matter with 0.18kPa. While both unconditioned viscous time constants were larger in gray than in white matter, both conditioned constants were smaller. These rheological differences suggest a different porosity between both tissues and explain-at least in part-the ongoing controversy between reported stiffness differences in gray and white matter. Our unconditioned and conditioned parameter sets are readily available for finite element simulations with commercial software packages that feature Ogden type models at finite deformations. As such, our results have direct implications on improving the accuracy of human brain simulations in health and disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Effect of different calcium phosphate scaffold ratios on odontogenic differentiation of human dental pulp cells

    Energy Technology Data Exchange (ETDEWEB)

    AbdulQader, Sarah Talib [School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia); Department of Pedodontic and Preventive Dentistry, College of Dentistry, University of Baghdad, Baghdad (Iraq); Kannan, Thirumulu Ponnuraj, E-mail: kannan@usm.my [School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia); Human Genome Centre, School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia); Rahman, Ismail Ab [School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia); Ismail, Hanafi [School of Materials and Minerals Resource Engineering, Universiti Sains Malaysia, 14300 Penang (Malaysia); Mahmood, Zuliani [School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia)

    2015-04-01

    Calcium phosphate (CaP) scaffolds have been widely and successfully used with osteoblast cells for bone tissue regeneration. However, it is necessary to investigate the effects of these scaffolds on odontoblast cells' proliferation and differentiation for dentin tissue regeneration. In this study, three different hydroxyapatite (HA) to beta tricalcium phosphate (β-TCP) ratios of biphasic calcium phosphate (BCP) scaffolds, BCP20, BCP50, and BCP80, with a mean pore size of 300 μm and 65% porosity were prepared from phosphoric acid (H{sub 2}PO{sub 4}) and calcium carbonate (CaCO{sub 3}) sintered at 1000 °C for 2 h. The extracts of these scaffolds were assessed with regard to cell viability and differentiation of odontoblasts. The high alkalinity, more calcium, and phosphate ions released that were exhibited by BCP20 decreased the viability of human dental pulp cells (HDPCs) as compared to BCP50 and BCP80. However, the cells cultured with BCP20 extract expressed high alkaline phosphatase activity and high expression level of bone sialoprotein (BSP), dental matrix protein-1 (DMP-1), and dentin sialophosphoprotein (DSPP) genes as compared to that cultured with BCP50 and BCP80 extracts. The results highlighted the effect of different scaffold ratios on the cell microenvironment and demonstrated that BCP20 scaffold can support HDPC differentiation for dentin tissue regeneration. - Highlights: • BCPs of different HA/β-TCP ratios influence cell microenvironment. • BCP20 decreases cell viability of HDPCs as compared to BCP50 and BCP80. • HDPCs cultured with BCP20 express highest ALP activity. • HDPCs cultured with BCP20 up-regulate BSP, DMP-1 and DSPP gene expressions. • BCP20 can support HDPC differentiation for dentin tissue regeneration.

  4. Polarized spectral features of human breast tissues through wavelet ...

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... Fluorescence characteristics of human breast tissues are investigated through wavelet transform and principal component analysis (PCA). Wavelet transform of polarized fluorescence spectra of human breast tissues is found to localize spectral features that can reliably differentiate different tissue types.

  5. Classification and Numbering of Dental Radiographs for an Automated Human Identification System

    Directory of Open Access Journals (Sweden)

    Anny Yuniarti

    2012-03-01

    Full Text Available Dental based human identification is commonly used in forensic. This is due to the teeth are resistant to temperatures up to 200C and are not easily got rotten. Thus, teeth are suit for victim identification of natural disaster, fire, bombing, etc. In this paper, we developed an automated human identification system based on dental radiographs. The system has two main stages, the first stage is to arrange a database consisting of labeled dental radiographs, and the second stage is the searching process in the database in order to retrieve the identification result. Both stages use a number of image processing techniques, classification methods, and a numbering system in order to generate dental radiographs features and patterns. Our experiments using 6 bitewing and 10 panoramic radiographs that consist of 119 tooth objects in total, has shown good performance of classification. The accuracy of dental pattern classification and dental numbering system are 91.6 % and 81.5% respectively.

  6. Revisiting dental fluctuating asymmetry in neandertals and modern humans.

    Science.gov (United States)

    Barrett, Christopher K; Guatelli-Steinberg, Debbie; Sciulli, Paul W

    2012-10-01

    Previous studies have suggested that Neandertals experienced greater physiological stress and/or were less capable of mitigating stress than most prehistoric modern human populations. The current study compares estimates of dental fluctuating asymmetry (DFA) for prehistoric Inupiat from Point Hope Alaska, the Late Archaic, and Protohistoric periods from Ohio and West Virginia, and a modern sample from Ohio to Neandertals from Europe and Southwest Asia. DFA results from developmental perturbation during crown formation and is thus an indicator of developmental stress, which previous studies have found to be higher in Neandertals than in several modern human populations. Here, we use recent methodological improvements in the analysis of fluctuating asymmetry suggested by Palmer and Strobeck (Annu Rev Ecol Syst 17 (1986) 391-421, Developmental instability: causes and consequences (2003a) v.1-v.36, Developmental instability: causes and consequences (2003b) 279-319) and compare the fit of Neandertal DFA Index values with those of modern humans. DFA estimates for each of the modern population samples exceeded measurement error, with the Inupiat exhibiting the highest levels of DFA for most tooth positions. All significant Neandertal z-scores were positive, exceeding the estimates for each of the modern prehistoric groups. Neandertals exhibited the fewest significant differences from the Inupiat (9.2% of values are significant at P Neandertal z-scores are significant at P Neandertals were under greater developmental stress than all other prehistoric modern human samples. Copyright © 2012 Wiley Periodicals, Inc.

  7. In Vitro Osteogenic and Odontogenic Differentiation of Human Dental Pulp Stem Cells Seeded on Carboxymethyl Cellulose-Hydroxyapatite Hybrid Hydrogel.

    Directory of Open Access Journals (Sweden)

    Gabriella eTeti

    2015-10-01

    Full Text Available Stem cells from human dental pulp have been considered as an alternative source of adult stem cells in tissue engineering because of their potential to differentiate into multiple cell lineages.Recently, polysaccharide based hydrogels have become especially attractive as matrices for the repair and regeneration of a wide variety of tissues and organs. The incorporation of inorganic minerals as hydroxyapatite nanoparticles can modulate the performance of the scaffolds with potential applications in tissue engineering. The aim of this study was to verify the osteogenic and odontogenic differentiation of dental pulp stem cells (DPSCs cultured on a carboxymethyl cellulose—hydroxyapatite hybrid hydrogel. Human DPSCs were seeded on carboxymethyl cellulose—hydroxyapatite hybrid hydrogel and on carboxymethyl cellulose hydrogel for 1, 3, 5, 7, 14 and 21 days. Cell viability assay and ultramorphological analysis were carried out to evaluate biocompatibility and cell adhesion. Real Time PCR was carried out to demonstrate the expression of osteogenic and odontogenic markers. Results showed a good adhesion and viability in cells cultured on carboxymethyl cellulose—hydroxyapatite hybrid hydrogel, while a low adhesion and viability was observed in cells cultured on carboxymethyl cellulose hydrogel. Real Time PCR data demonstrated a temporal up-regulation of osteogenic and odontogenic markers in dental pulp stem cells cultured on carboxymethyl cellulose—hydroxyapatite hybrid hydrogel. In conclusion, our in vitro data confirms the ability of DPSCs to differentiate toward osteogenic and odontogenic lineages in presence of a carboxymethyl cellulose—hydroxyapatite hybrid hydrogel. Taken together, our results provide evidence that DPSCs and carboxymethyl cellulose—hydroxyapatite hybrid hydrogel could be considered promising candidates for dental pulp complex and periodontal tissue engineering.

  8. Dynamic Properties of Human Bronchial Airway Tissues

    CERN Document Server

    Wang, Jau-Yi; Pallai, Prathap; Corrigan, Chris J; Lee, Tak H

    2011-01-01

    Young's Modulus and dynamic force moduli were measured on human bronchial airway tissues by compression. A simple and low-cost system for measuring the tensile-strengh of soft bio-materials has been built for this study. The force-distance measurements were undertaken on the dissected bronchial airway walls, cartilages and mucosa from the surgery-removed lungs donated by lung cancer patients with COPD. Young's modulus is estimated from the initial slope of unloading force-displacement curve and the dynamic force moduli (storage and loss) are measured at low frequency (from 3 to 45 Hz). All the samples were preserved in the PBS solution at room temperature and the measurements were perfomed within 4 hours after surgery. Young's modulus of the human bronchial airway walls are fond ranged between 0.17 and 1.65 MPa, ranged between 0.25 to 1.96 MPa for cartilages, and between 0.02 to 0.28 MPa for mucosa. The storage modulus are found varying 0.10 MPa with frequency while the loss modulus are found increasing from ...

  9. [Healing Dental and Oral Problems by Remedies of Animal and of Human Origin].

    Science.gov (United States)

    Kaán, Miklós

    2015-01-01

    Use of matierials of animal or human origin in dentistry (and generally in medicine) these days is regarded as an unusal way of intervention. However in earlier times, different tissues, parts, products and organs of animals were frequently used in healing. Some of these methods were rooted in magical thinking. As analogical treatments--based on similarity or analogy--e.g. powder of horn or teeth of pike was used for the treatment of decayed teeth and different worms, maggots, veenies were applied against "toothworm". By difficult eruption of primary teeth bone marrow or brain mixed with cockridge-blood and goatmilk was a widely used medicine. Butter and honey were able to help the growing of teeth, as well. Parts of frog (fe: flippers) were also components of curing materials. Egg as the symbol of life was often an ingredient of medicaments. For the treatment of inflamed gum different animal materials were used, like chin and teeth of wolf, pike, crayfish, milk, honey, human saliva etc. Animal or human stools, mucks (containing enzymes) did one's bit in healing of oral and dental illnesses and were applied as fomentation or swathing. Placing a leech on the inflamed face was a common procedure in the past even as the use of earwax in lipnook. In our days tissues, parts or products of animals (or human beings) usually never allowed to get into contact with the body of patients. It's a much safer routine, at the same time however a precious traditional knowledge vanishes forever.

  10. 2010 Great Lakes Human Health Fish Tissue Study Fish Tissue Data Dictionary

    Science.gov (United States)

    The Office of Science and Technology (OST) is providing the fish tissue results from the 2010 Great Lakes Human Health Fish Tissue Study (GLHHFTS). This document includes the “data dictionary” for Mercury, PFC, PBDE and PCBs.

  11. Inflammatory response of human dental pulp to at-home and in-office tooth bleaching

    Directory of Open Access Journals (Sweden)

    Maysa Magalhães Vaz

    Full Text Available ABSTRACT Tooth bleaching is a technique of choice to obtain a harmonious smile, but bleaching agents may damage the dental pulp. Objective: This study evaluated the inflammatory responses of human dental pulp after the use of two bleaching techniques. Material and Methods: Pulp samples were collected from human third molars extracted for orthodontic reasons and divided into three groups: control - no tooth bleaching (CG (n=7; at-home bleaching with 15% carbamide peroxide (AH (n = 10, and in-office bleaching with 38% hydrogen peroxide (IO (n=12. Pulps were removed and stained with hematoxylin-eosin for microscopic analysis of inflammation intensity, collagen degradation, and pulp tissue organization. Immunohistochemistry was used to detect mast cells (tryptase+, blood vessels (CD31+, and macrophages (CD68+. Chi-square, Kruskal-Wallis, and Mann Whitney tests were used for statistical analysis. The level of significance was set at p0.05. No mast cells were found in the pulp samples analyzed. Conclusion: In-office bleaching with 38% hydrogen peroxide resulted in more intense inflammation, higher macrophages migration, and greater pulp damage then at-home bleaching with 15% carbamide peroxide, however, these bleaching techniques did not induce migration of mast cells and increased the number of blood vessels.

  12. Low-intensity lasers, modern filling materials, and bonding systems influence on mineral metabolism of hard dental tissues

    Science.gov (United States)

    Kunin, Anatoly A.; Yesaulenko, I. E.; Zoibelmann, M.; Pankova, Svetlana N.; Ippolitov, Yu. A.; Oleinik, Olga I.; Popova, T. A.; Koretskaya, I. V.; Shumilovitch, Bogdan R.; Podolskaya, Elana E.

    2001-10-01

    One of the main reasons of low quality filling is breaking Ca-P balance in hard tissues. Our research was done with the purpose of studying the influence of low intensity lasers, diodic radiation, the newest filling and bonding systems on the processes of mineral metabolism in hard dental tissues while filling a tooth. 250 patients having caries and its compli-cations were examined and treated. Our complex research included: visual and instrumental examination, finding out the level of oral cavity hygiene, acid enamel biopsy, scanning electronic microscopy and X-ray spectrum microanalysis. Filling processes may produce a negative effect on mineral metabolism of hard dental tissues the latter is less pronounced when applying fluoride-containing filling materials with bonding systems. It has also been found that bonding dentin and enamel systems are designed for both a better filling adhesion (i.e. mechanical adhesion) and migration of useful microelements present in them by their sinking into hard dental tissues (i.e. chemical adhesion). Our research showed a positive influence of low intensity laser and diodic beams accompanying the use of modern filling and bonding systems on mineral metabolism of hard dental tissues.

  13. 21 CFR 876.5885 - Tissue culture media for human ex vivo tissue and cell culture processing applications.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tissue culture media for human ex vivo tissue and... DEVICES Therapeutic Devices § 876.5885 Tissue culture media for human ex vivo tissue and cell culture processing applications. (a) Identification. Tissue culture media for human ex vivo tissue and cell culture...

  14. Genetic Comparison of Stemness of Human Umbilical Cord and Dental Pulp

    Directory of Open Access Journals (Sweden)

    Chung-Min Kang

    2016-01-01

    Full Text Available This study focuses on gene expression patterns and functions in human umbilical cord (UC and dental pulp (DP containing mesenchymal stem cells (MSCs. DP tissues were collected from 25 permanent premolars. UC tissue samples were obtained from three newborns. Comparative gene profiles were obtained using cDNA microarray analysis and the expression of tooth development-associated and MSC-related genes was assessed by the quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR. Genes related to cell proliferation, angiogenesis, and immune responses were expressed at higher levels in UC, whereas genes related to growth factor and receptor activity and signal transduction were more highly expressed in DP. Although UC and DP tissues exhibited similar expression of surface markers for MSCs, UC showed higher expression of CD29, CD34, CD44, CD73, CD105, CD146, and CD166. qRT-PCR analysis showed that CD146, CD166, and MYC were expressed 18.3, 8.24, and 1.63 times more highly in UC, whereas the expression of CD34 was 2.15 times higher in DP. Immunohistochemical staining revealed significant differences in the expression of genes (DSPP, DMP1, and CALB1 related to odontogenesis and angiogenesis in DP. DP and UC tissue showed similar gene expression, with the usual MSC markers, while they clearly diverged in their differentiation capacity.

  15. Encapsulated dental-derived mesenchymal stem cells in an injectable and biodegradable scaffold for applications in bone tissue engineering.

    Science.gov (United States)

    Moshaverinia, Alireza; Chen, Chider; Akiyama, Kentaro; Xu, Xingtian; Chee, Winston W L; Schricker, Scott R; Shi, Songtao

    2013-11-01

    Bone grafts are currently the major family of treatment options in modern reconstructive dentistry. As an alternative, stem cell-scaffold constructs seem to hold promise for bone tissue engineering. However, the feasibility of encapsulating dental-derived mesenchymal stem cells in scaffold biomaterials such as alginate hydrogel remains to be tested. The objectives of this study were, therefore, to: (1) develop an injectable scaffold based on oxidized alginate microbeads encapsulating periodontal ligament stem cells (PDLSCs) and gingival mesenchymal stem cells (GMSCs); and (2) investigate the cell viability and osteogenic differentiation of the stem cells in the microbeads both in vitro and in vivo. Microbeads with diameters of 1 ± 0.1 mm were fabricated with 2 × 10(6) stem cells/mL of alginate. Microbeads containing PDLSCs, GMSCs, and human bone marrow mesenchymal stem cells as a positive control were implanted subcutaneously and ectopic bone formation was analyzed by micro CT and histological analysis at 8-weeks postimplantation. The encapsulated stem cells remained viable after 4 weeks of culturing in osteo-differentiating induction medium. Scanning electron microscopy and X-ray diffraction results confirmed that apatitic mineral was deposited by the stem cells. In vivo, ectopic mineralization was observed inside and around the implanted microbeads containing the immobilized stem cells. These findings demonstrate for the first time that immobilization of PDLSCs and GMSCs in alginate microbeads provides a promising strategy for bone tissue engineering. Copyright © 2013 Wiley Periodicals, Inc.

  16. The Regulatory Effects of Long Noncoding RNA-ANCR on Dental Tissue-Derived Stem Cells

    Directory of Open Access Journals (Sweden)

    Qian Jia

    2016-01-01

    Full Text Available Long noncoding RNAs (lncRNA have been recognized as important regulators in diverse biological processes, such as transcriptional regulation, stem cell proliferation, and differentiation. Previous study has demonstrated that lncRNA-ANCR (antidifferentiation ncRNA plays a key role in regulating the proliferation and osteogenic differentiation of periodontal ligament stem cells (PDLSCs. However, little is known about the role of ANCR in regulating other types of dental tissue-derived stem cells (DTSCs behaviours (including proliferation and multiple-potential of differentiation. In this study, we investigated the regulatory effects of lncRNA-ANCR on the proliferation and differentiation (including osteogenic, adipogenic, and neurogenic differentiation of DTSCs, including dental pulp stem cells (DPSCs, PDLSCs, and stem cells from the apical papilla (SCAP by downregulation of lncRNA-ANCR. We found that downregulation of ANCR exerted little effect on proliferation of DPSCs and SCAP but promoted the osteogenic, adipogenic, and neurogenic differentiation of DTSCs. These data provide an insight into the regulatory effects of long noncoding RNA-ANCR on DTSCs and indicate that ANCR is a very important regulatory factor in stem cell differentiation.

  17. Interaction of Er,Cr:YSGG laser with dental hard tissue

    Directory of Open Access Journals (Sweden)

    Abbas Majdabadi

    2016-11-01

    Full Text Available Background and Aims: Nowadays lasers are used as alternatives to the tooth preparation because of reducing pain, bloodshed and stress. The aim of this study was to observe the effect of Er,Cr:YSGG laser on the dental hard tissues. Materials and Methods: For this studty, molar teeth with no caries or dental restoration and enamel cracks were used. The laser power were taken from 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5 up to 6 Watts for enamel and 0.5, 1, 1.5, 2, 2.5, 3, 3.5 and 4 Watts for dentine simultaneously with water spray. The ablation effect was observed on both enamel and dentine. Finally, by use of a CCD camera connected to the computer, the dimensions of ablated areas were measured and results were applied in graphs. Results: Volume of ablation was increased by increasing laser power. Also, by increasing energy value in each stage, the depth of ablation was increased for enamel and dentine. SEM images of ablations by 3.5 and 4 Watts on enamel and 1 and 1.5 Watts on dentine did not show any sharp edges. Conclusion: The ablation volumes and depth increased by increasing the energy of laser pulses power. The reason for this trend was due to the water spray while irradiating and good absorption of water by laser beam.

  18. Can surface preparation with CVD diamond tip influence on bonding to dental tissues?

    Science.gov (United States)

    Aparecido Kawaguchi, Fernando; Brossi Botta, Sergio; Nilo Vieira, Samuel; Steagall Júnior, Washington; Bona Matos, Adriana

    2008-04-01

    This study evaluated the influence of chemical vapor deposition (CVD) tips surface treatments of enamel and dentin on bonding resistance of two adhesive systems. Thirty embedded samples were divided in 12 groups ( n = 10), according to factors: substrate (enamel and dentin), adhesive system [etch-and-rinse (SB) and self-etch]; and the surface treatments (paper discs, impact CVD tips and tangential CVD tip). When CVD tip was used in the impact mode the tip was applied perpendicular to dental surface, while at tangential mode, the tip worked parallel to dental surface. Specimens were tested in tension after 24 h at 0.5 mm/min of cross-head speed. ANOVA results, in MPa showed that in enamel, only adhesive system factor was statistically significant ( p = 0.015) under tested conditions, with higher bond strength observed for SB groups. However, in dentin the best bonding performance was obtained in SE groups ( p = 0.00). In both tested substrates, results did not show statistically significant difference for factors treatment and its interactions. ConclusionsIt may be concluded that CVD-tip surface treatment, in both tested modes, did not influence on adhesion to enamel and dentin. But, it is important to choose adhesive system according to the tissue available to bonding.

  19. FORUM Human tissue and organ transplant provisions: Chapter 8 of ...

    African Journals Online (AJOL)

    permanent residents; (iii) donations of human bodies and tissue of deceased persons; (iv) consent to donations of human tissue on behalf of deceased persons; (v) allocation and use of human organs of ... It is also an offence to sell or trade.

  20. Handbook of Human Tissue Sources. A National Resource of Human Tissue Samples

    Science.gov (United States)

    1999-01-01

    supplemental calcium for the prevention of preeclampsia during pregnancy. Five clinical centers, enrolling 4,500 women over a two-year period...Centers for Disease Control and Prevention Institutes 106 National Center for Environmental Health 106 National Center for Infectious Diseases...and Prevention Complementary DNA (deoxyribonucleic acid) xxiv Handbook of Human Tissue Sources CFRBCS CGOP CHR CHTN CJD CLIA CLSS CME CMV

  1. Age-related changes of dental pulp tissue after experimental tooth movement in rats

    Directory of Open Access Journals (Sweden)

    Martina Von Böhl

    2016-01-01

    Full Text Available It is generally accepted that the effect of orthodontic tooth movement on the dental pulp in adolescents is reversible and that it has no long-lasting effect on pulpal physiology. However, it is not clear yet if the same conclusion is also valid for adult subjects. Thus, in two groups of rats, aged 6 and 40 weeks respectively, 3 molars at one side of the maxilla were moved together in a mesial direction with a standardized orthodontic appliance delivering a force of 10 cN. The contralateral side served as a control. Parasagittal histological sections were prepared after tooth movement for 1, 2, 4, 8, and 12 weeks. The pulp tissue was characterized for the different groups, with special emphasis on cell density, inflammatory cells, vascularity, and odontoblasts. Dimensions of dentin and the pulpal horns was determined and related with the duration of orthodontic force application and age ware evaluated. We found that neither in young nor in adult rats, force application led to long-lasting or irreversible changes in pulpal tissues. Dimensional variables showed significant age-related changes. In conclusion, orthodontic tooth movement per se has no long-lasting or irreversible effect on pulpal tissues, neither in the young nor in the adult animals.

  2. Precise femtosecond laser ablation of dental hard tissue: preliminary investigation on adequate laser parameters

    Science.gov (United States)

    Hikov, Todor; Pecheva, Emilia; Montgomery, Paul; Antoni, Frederic; Leong-Hoi, Audrey; Petrov, Todor

    2017-01-01

    This work aims at evaluating the possibility of introducing state-of-the-art commercial femtosecond laser system in restorative dentistry by maintaining well-known benefits of lasers for caries removal, but also in overcoming disadvantages such as thermal damage of irradiated substrate. Femtosecond ablation of dental hard tissue is investigated by changing the irradiation parameters (pulsed laser energy, scanning speed and pulse repetition rate), assessed for enamel and dentin. The femtosecond laser system used in this work may be suitable for cavity preparation in dentin and enamel, due to the expected effective ablation and low temperature increase when using ultra short laser pulses. If adequate laser parameters are selected, this system seems to be promising for promoting a laser-assisted, minimally invasive approach in restorative dentistry.

  3. Infrared spectroscopy of laser-irradiated dental hard tissues using the Advanced Light Source

    Science.gov (United States)

    Fried, Daniel; Breunig, Thomas

    2001-04-01

    FTIR spectroscopy used in the specular reflectance mode is well suited for resolving thermally induced changes in dental hard tissue as a result of laser irradiation. High spatial resolution is achievable with a high brightness synchrotron radiation source such as the ALS at Lawrence Berkeley National Laboratory. IR spectra of modified enamel were acquired after laser ablation using several laser wavelengths from the UV to the mid-IR. Specific areas of laser ablation craters were probed non-destructively with 10-micrometers spatial resolution. The chemical composition of the crater walls deviates markedly from that of hydroxyapatite after Er:YAG and CO2 laser irradiation without added water. New mineral phases were resolved that have not been previously observed using conventional IR spectroscopy.

  4. Enoxacin penetration into human prostatic tissue.

    Science.gov (United States)

    Bergeron, M G; Roy, R; Lessard, C; Foucault, P

    1988-01-01

    Concurrent enoxacin concentrations in serum and prostatic tissue were determined in 14 patients. The mean ratios of enoxacin concentration in tissue over concentration in serum were 1.4 +/- 0.2 (standard error of the mean). The levels in serum and prostatic tissue were above the MICs for most urinary pathogens. PMID:3196004

  5. Dielectric characterisation of human tissue samples

    NARCIS (Netherlands)

    Rossum, W.L. van; Nennie, F.; Deiana, D.; Veen, A.J. van der; Monni, S.

    2014-01-01

    The electrical properties of tissues samples are required for investigation and simulation purposes in biomedical applications of EM sensors. While available open literature mostly deals with ex-vivo characterization of isolated tissues, knowledge on dielectric properties of these tissues in their

  6. Gentamicin concentrations in human subcutaneous tissue

    DEFF Research Database (Denmark)

    Lorentzen, Hanne; Kallehave, Finn Lasse; Kolmos, Hans Jørn Jepsen

    1996-01-01

    Wound infections frequently originate from the subcutaneous tissue. The effect of gentamicin in subcutaneous tissue has, however, normally been evaluated from concentrations in blood or wound fluid. The aim of the present study was to investigate the pharmacokinetic properties of gentamicin in hu...... the presence of sufficient concentrations in the adipose tissue to be effective against common bacteria....

  7. Incremental growth of therizinosaurian dental tissues: implications for dietary transitions in Theropoda

    Science.gov (United States)

    You, Hailu; Kirkland, James I.; Zanno, Lindsay

    2017-01-01

    Previous investigations document functional and phylogenetic signals in the histology of dinosaur teeth. In particular, incremental lines in dentin have been used to determine tooth growth and replacement rates in several dinosaurian clades. However, to date, few studies have investigated the dental microstructure of theropods in the omnivory/herbivory spectrum. Here we examine dental histology of Therizinosauria, a clade of large-bodied theropods bearing significant morphological evidence for herbivory, by examining the teeth of the early-diverging therizinosaurian Falcarius utahensis, and an isolated tooth referred to Suzhousaurus megatherioides, a highly specialized large-bodied representative. Despite attaining some of the largest body masses among maniraptoran theropod dinosaurs, therizinosaurian teeth are diminutive, measuring no more than 0.90 cm in crown height (CH) and 0.38 cm in crown base length (CBL). Comparisons with other theropods and non-theropodan herbivorous dinosaurs reveals that when controlling for estimated body mass, crown volume in therizinosaurians plots most closely with dinosaurs of similar dietary strategy as opposed to phylogenetic heritage. Analysis of incremental growth lines in dentin, observed in thin sections of therizinosaurian teeth, demonstrates that tooth growth rates fall within the range of other archosaurs, conforming to hypothesized physiological limitations on the production of dental tissues. Despite dietary differences between therizinosaurians and hypercarnivorous theropods, the types of enamel crystallites present and their spatial distribution—i.e., the schmelzmuster of both taxa—is limited to parallel enamel crystallites, the simplest form of enamel and the plesiomorphic condition for Theropoda. This finding supports previous hypotheses that dental microstructure is strongly influenced by phylogeny, yet equally supports suggestions of reduced reliance on oral processing in omnivorous/herbivorous theropods rather

  8. Incremental growth of therizinosaurian dental tissues: implications for dietary transitions in Theropoda

    Directory of Open Access Journals (Sweden)

    Khai Button

    2017-12-01

    Full Text Available Previous investigations document functional and phylogenetic signals in the histology of dinosaur teeth. In particular, incremental lines in dentin have been used to determine tooth growth and replacement rates in several dinosaurian clades. However, to date, few studies have investigated the dental microstructure of theropods in the omnivory/herbivory spectrum. Here we examine dental histology of Therizinosauria, a clade of large-bodied theropods bearing significant morphological evidence for herbivory, by examining the teeth of the early-diverging therizinosaurian Falcarius utahensis, and an isolated tooth referred to Suzhousaurus megatherioides, a highly specialized large-bodied representative. Despite attaining some of the largest body masses among maniraptoran theropod dinosaurs, therizinosaurian teeth are diminutive, measuring no more than 0.90 cm in crown height (CH and 0.38 cm in crown base length (CBL. Comparisons with other theropods and non-theropodan herbivorous dinosaurs reveals that when controlling for estimated body mass, crown volume in therizinosaurians plots most closely with dinosaurs of similar dietary strategy as opposed to phylogenetic heritage. Analysis of incremental growth lines in dentin, observed in thin sections of therizinosaurian teeth, demonstrates that tooth growth rates fall within the range of other archosaurs, conforming to hypothesized physiological limitations on the production of dental tissues. Despite dietary differences between therizinosaurians and hypercarnivorous theropods, the types of enamel crystallites present and their spatial distribution—i.e., the schmelzmuster of both taxa—is limited to parallel enamel crystallites, the simplest form of enamel and the plesiomorphic condition for Theropoda. This finding supports previous hypotheses that dental microstructure is strongly influenced by phylogeny, yet equally supports suggestions of reduced reliance on oral processing in omnivorous

  9. Scanning electron microscopy and ablation rates of hard dental tissue using 350-fs and 1-ns laser pulses

    Science.gov (United States)

    Neev, Joseph; Huynh, Daniel S.; Dan, Claudiu C.; White, Joel M.; Da Silva, Luiz B.; Feit, Michael D.; Matthews, Dennis L.; Perry, Michael D.; Rubenchik, Alexander M.; Stuart, Brent C.

    1996-04-01

    Lasers are currently limited in their ability to remove hard tissue. Furthermore, many laser systems, such as the long pulse infrared lasers used to ablate bone or hard dental tissue, also generate unacceptable heat levels and cause collateral tissue damage. Ultrashort pulse lasers, however, are highly efficient, quiet, and relatively free of charge. With recent developments now allowing operation at high pulse repetition rates, ultrashort pulse systems can yield significant material volume removal which can potentially match or even exceed conventional technology while still maintaining the minimal collateral damage characteristics. In this paper, the interaction characteristics of two pulse regimes with enamel and dentin: 350 fs pulse ablation of hard dental tissues is compared to the interaction with one nanosecond pulses. Ablation rates were characterized and surface morphology, and structure were evaluated using a scanning electron microscope.

  10. Cadmium Concentration in Human Autopsy Tissues.

    Science.gov (United States)

    Lech, Teresa; Sadlik, Józefa K

    2017-10-01

    The concentration of cadmium in human tissues obtained on the basis of autopsies of non-poisoned Polish people (n = 150), aged from 1 to 80 years, examined between 1990 and 2010, is presented. The following values were found in wet digested samples by flame atomic absorption spectrometry (FAAS) (mean ± SD, median, and range, μg/g of wet weight): brain 0.020 ± 0.031, 0.084, 0-0.120 (n = 41); stomach 0.148 ± 0.195, 0.084, 0-1.25 (n = 89); small intestine 0.227 ± 0.231, 0.130, 0-0.830 (n = 39); liver 1.54 ± 1.55, 1.01, 0.015-9.65 (n = 99); kidney 16.0 ± 13.2, 14.0, 0.62-61.3 (n = 91); lung 0.304 ± 0.414, 0.130, 0-1.90 (n = 25); and heart 0.137 ± 0.107, 0.140, 0.017-0.250 (n = 4). Additionally, results (n = 13 people, aged from 2 to 83 years, 63 samples) obtained by inductively coupled plasma optical emission spectrometry (ICP OES) between 2010 and 2015 are given. The obtained data on Cd concentration in the human body can be used to estimate the amounts occurring in "healthy" people and those occurring in cases of chronic or acute poisonings with Cd compounds, which are examined for forensic purposes or to assess environmental exposure levels.

  11. Partial characterization of lysyl oxidase from several human tissues.

    OpenAIRE

    Kuivaniemi, H

    1985-01-01

    Lysyl oxidase activity was assayed in urea extracts of a number of human tissues, proving to be highest in skin. Antibodies to human placental lysyl oxidase completely inhibited the activity of crude lysyl oxidase from all the human tissues studied, with no significant differences in the amounts of antiserum required for 50% inhibition. By contrast, marked differences were found in this value between skin tissue samples from different species. The Mr of lysyl oxidase in crude extracts of huma...

  12. Mapping the spatial and temporal progression of human dental enamel biomineralization using synchrotron X-ray diffraction.

    Science.gov (United States)

    Simmons, Lisa M; Montgomery, Janet; Beaumont, Julia; Davis, Graham R; Al-Jawad, Maisoon

    2013-11-01

    The complex biological, physicochemical process of human dental enamel formation begins in utero and for most teeth takes several years to complete. Lost enamel tissue cannot regenerate, therefore a better understanding of the spatial and temporal progression of mineralization of this tissue is needed in order to design improved in vivo mineral growth processes for regenerative dentistry and allow the possibility to grow a synthetic whole or partial tooth. Human dental enamel samples across a range of developmental stages available through archaeological collections have been used to explore the spatial and temporal progression of enamel biomineralization. Position sensitive synchrotron X-ray diffraction was used to quantify spatial and temporal variations in crystallite organization, lattice parameters and crystallite thickness at three different stages in enamel maturation. In addition X-ray microtomography was used to study mineral content distributions. An inverse correlation was found between the spatial variation in mineral content and the distribution of crystallite organization and thickness as a function of time during enamel maturation. Combined X-ray microtomography and synchrotron X-ray diffraction results show that as enamel matures the mineral content increases and the mineral density distribution becomes more homogeneous. Starting concurrently but proceeding at a slower rate, the enamel crystallites become more oriented and larger; and the crystallite organization becomes spatially more complex and heterogeneous. During the mineralization of human dental enamel, the rate of mineral formation and mineral organization are not identical. Whilst the processes start simultaneously, full mineral content is achieved earlier, and crystallite organization is slower and continues for longer. These findings provide detailed insights into mineral development in human dental enamel which can inform synthetic biomimetic approaches for the benefit of clinical

  13. Proteome of human stem cells from periodontal ligament and dental pulp.

    Directory of Open Access Journals (Sweden)

    Enrica Eleuterio

    Full Text Available BACKGROUND: Many adult tissues contain a population of stem cells with the ability to regenerate structures similar to the microenvironments from which they are derived in vivo and represent a promising therapy for the regeneration of complex tissues in the clinical disorder. Human adult stem cells (SCs including bone marrow stem cells (BMSCs, dental pulp stem cells (DPSCs and periodontal ligament stem cells (PDLSCs have been characterized for their high proliferative potential, expression of characteristic SC-associated markers and for the plasticity to differentiate in different lineage in vitro. METHODOLOGY/PRINCIPAL FINDINGS: The aim of this study is to define the molecular features of stem cells from oral tissue by comparing the proteomic profiles obtained with 2-DE followed by MALDI-TOF/TOF of ex-vivo cultured human PDLSCs, DPSCs and BMSCs. Our results showed qualitative similarities in the proteome profiles among the SCs examined including some significant quantitative differences. To enrich the knowledge of oral SCs proteome we performed an analysis in narrow range pH 4-7 and 6-9, and we found that DPSCs vs PDLSCs express differentially regulated proteins that are potentially related to growth, regulation and genesis of neuronal cells, suggesting that SCs derived from oral tissue source populations may possess the potential ability of neuronal differentiation which is very consistent with their neural crest origin. CONCLUSION/SIGNIFICANCE: This study identifies some differentially expressed proteins by using comparative analysis between DPSCs and PDLSCs and BMSCs and suggests that stem cells from oral tissue could have a different cell lineage potency compared to BMSCs.

  14. Manufacturing of dental pulp cell-based products from human third molars: current strategies and future investigations

    Directory of Open Access Journals (Sweden)

    Maxime eDucret

    2015-08-01

    Full Text Available In recent years, mesenchymal cell-based products have been developed to improve surgical therapies aimed at repairing human tissues. In this context, the tooth has recently emerged as a valuable source of stem/progenitor cells for regenerating orofacial tissues, with easy access to pulp tissue and high differentiation potential of dental pulp mesenchymal cells. International guidelines now recommend the use of standardized procedures for cell isolation, storage and expansion in culture to ensure optimal reproducibility, efficacy and safety when cells are used for clinical application. However, most dental pulp cell-based medicinal products manufacturing procedures may not be fully satisfactory since they could alter the cells biological properties and the quality of derived products. Cell isolation, enrichment and cryopreservation procedures combined to long-term expansion in culture media containing xeno- and allogeneic components are known to affect cell phenotype, viability, proliferation and differentiation capacities. This article focuses on current manufacturing strategies of dental pulp cell-based medicinal products and proposes a new protocol to improve efficiency, reproducibility and safety of these strategies.

  15. Transcriptomics resources of human tissues and organs

    DEFF Research Database (Denmark)

    Uhlén, Mathias; Hallström, Björn M.; Lindskog, Cecilia

    2016-01-01

    Quantifying the differential expression of genes in various human organs, tissues, and cell types is vital to understand human physiology and disease. Recently, several large-scale transcriptomics studies have analyzed the expression of protein-coding genes across tissues. These datasets provide...... a framework for defining the molecular constituents of the human body as well as for generating comprehensive lists of proteins expressed across tissues or in a tissue-restricted manner. Here, we review publicly available human transcriptome resources and discuss body-wide data from independent genome...... in all tissues and relatively few in a tissue-restricted manner. Moreover, we discuss the applications of publicly available omics data for building genome-scale metabolic models, used for analyzing cell and tissue functions both in physiological and in disease contexts....

  16. Comparison of dental measurement systems for taxonomic assignment of Neanderthal and modern human lower second deciduous molars.

    Science.gov (United States)

    Benazzi, Stefano; Fornai, Cinzia; Bayle, Priscilla; Coquerelle, Michael; Kullmer, Ottmar; Mallegni, Francesco; Weber, Gerhard W

    2011-09-01

    Traditional morphometric approaches for taxonomic assignment of Neanderthal and modern human dental remains are mainly characterized by caliper measurements of tooth crowns. Several studies have recently described differences in dental tissue proportions and enamel thickness between Neanderthal and modern human teeth. At least for the lower second deciduous molar (dm(2)), a three-dimensional lateral relative enamel thickness index has been proposed for separating the two taxa. This index has the advantage over other measurements of being applicable to worn teeth because it ignores the occlusal aspect of the crown. Nevertheless, a comparative evaluation of traditional crown dimensions and lateral dental tissue proportion measurements for taxonomic assignment of Neanderthal and modern human dm(2)s has not yet been performed. In this study, we compare various parameters gathered from the lateral aspects of the crown. These parameters include crown diameters, height of the lateral wall of the crown (lateral crown height = LCH), lateral enamel thickness, and dentine volume of the lateral wall, including the volume of the coronal pulp chamber (lateral dentine plus pulp volume = LDPV), in a 3D digital sample of Neanderthal and modern human dm(2)s to evaluate their utility in separating the two taxa. The LDPV and the LCH allow us to discriminate between Neanderthals and modern humans with 88.5% and 92.3% accuracy, respectively. Though our results confirm that Neanderthal dm(2)s have lower relative enamel thickness (RET) index compared with modern humans (p = 0.005), only 70% of the specimens were correctly classified on the basis of the RET index. We also emphasize that results of the lateral enamel thickness method depend on the magnitude of the interproximal wear. Accordingly, we suggest using the LCH or the LDPV to discriminate between Neanderthal and modern human dm(2)s. These parameters are more independent of interproximal wear and loss of lateral enamel. Copyright

  17. Effect of Melatonin on Human Dental Papilla Cells

    Directory of Open Access Journals (Sweden)

    Ryusuke Tachibana

    2014-09-01

    Full Text Available Melatonin regulates a variety of biological processes, which are the control of circadian rhythms, regulation of seasonal reproductive function and body temperature, free radical scavenging and so on. Our previous studies have shown that various cells exist in human and mouse tooth germs that express the melatonin 1a receptor (Mel1aR. However, little is known about the effects of melatonin on tooth development and growth. The present study was performed to examine the possibility that melatonin might exert its influence on tooth development. DP-805 cells, a human dental papilla cell line, were shown to express Mel1aR. Expression levels of mRNA for Mel1aR in DP-805 cells increased until 3 days after reaching confluence and decreased thereafter. Real-time reverse transcription-polymerase chain reaction showed that melatonin increased the expression of mRNAs for osteopontin (OPN, osteocalcin (OCN, bone sialoprotein (BSP, dentin matrix protein-1 (DMP-1 and dentin sialophosphoprotin (DSPP. Melatonin also enhanced the mineralized matrix formation in DP-805 cell cultures in a dose-dependent manner. These results strongly suggest that melatonin may play a physiological role in tooth development/growth by regulating the cellular function of odontogenic cells in tooth germs.

  18. Cell death effects of resin-based dental material compounds and mercurials in human gingival fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Reichl, Franz-Xaver [Walther-Straub-Institute of Pharmacology and Toxicology, Munich (Germany); Ludwig-Maximilians-University, Department of Operative Dentistry and Periodontology, Munich (Germany); Esters, Magali; Simon, Sabine; Seiss, Mario [Walther-Straub-Institute of Pharmacology and Toxicology, Munich (Germany); Kehe, Kai [Bundeswehr Institute of Pharmacology and Toxicology, Munich (Germany); Kleinsasser, Norbert [University of Regensburg, Head and Neck Surgery, Department of Otolaryngology, Regensburg (Germany); Folwaczny, Matthias; Glas, Juergen; Hickel, Reinhard [Ludwig-Maximilians-University, Department of Operative Dentistry and Periodontology, Munich (Germany)

    2006-06-15

    In order to test the hypothesis that released dental restorative materials can reach toxic levels in human oral tissues, the cytotoxicities of the resin-based dental (co)monomers hydroxyethylmethacrylate (HEMA), triethyleneglycoldimethacrylate (TEGDMA), urethanedimethacrylate (UDMA), and bisglycidylmethacrylate (BisGMA) compared with methyl mercury chloride (MeHgCl) and the amalgam component mercuric chloride (HgCl{sub 2}) were investigated on human gingival fibroblasts (HGF) using two different test systems: (1) the modified XTT-test and (2) the modified H 33342 staining assay. The HGF were exposed to various concentrations of the test-substances in all test systems for 24 h. All tested (co)monomers and mercury compounds significantly (P<0.05) decreased the formazan formation in the XTT-test. EC{sub 50} values in the XTT assay were obtained as half-maximum-effect concentrations from fitted curves. Following EC{sub 50} values were found (mean [mmol/l]; s.e.m. in parentheses; n=12; * significantly different to HEMA): HEMA 11.530 (0.600); TEGDMA* 3.460 (0.200); UDMA* 0.106 (0.005); BisGMA* 0.087 (0.001); HgCl{sub 2}* 0.013 (0.001); MeHgCl* 0.005 (0.001). Following relative toxicities were found: HEMA 1; TEGDMA 3; UDMA 109; BisGMA 133; HgCl{sub 2} 887; MeHgCl 2306. A significant (P<0.05) increase of the toxicity of (co)monomers and mercurials was found in the XTT-test in the following order: HEMA < TEGDMA < UDMA < BisGMA < HgCl{sub 2} < MeHgCl. TEGDMA and MeHgCl induced mainly apoptotic cell death. HEMA, UDMA, BisGMA, and HgCl{sub 2} induced mainly necrotic cell death. The results of this study indicate that resin composite components have a lower toxicity than mercury from amalgam in HGF. HEMA, BisGMA, UDMA, and HgCl{sub 2} induced mainly necrosis, but it is rather unlikely that eluted substances (solely) can reach concentrations, which might induce necrotic cell death in the human physiological situation, indicating that other (additional) factors may be involved in

  19. Interleukin-6 expression on inflamed rat dental pulp tissue after capped with Trigona sp. propolis from south Sulawesi, Indonesia

    Directory of Open Access Journals (Sweden)

    Ardo Sabir

    2017-07-01

    Full Text Available Background: Propolis is a natural product of plant resins collected by honeybees from various plant sources. It is used as a remedy in folk medicine since ancient times because of its several biological and pharmacological properties. Recently, propolis has been used by dentist to treat various oral diseases. It was always mentioned as an anti-inflammatory agent. Cytokines are proteins that provide communication between cells and play a critical role in a wide variety of processes. It released from cells in an inflammatory process that active, mediate or potential actions of other cells or tissues. When dental pulp has inflammation, several pro-inflammatory cytokines including Interleukin-6 (IL-6 was released by innate immune cells. Objective: To analyse the expression of IL-6 on inflamed rat dental pulp tissue following application of propolis. Material and methods: Trigona sp. propolis was obtained from Luwu Regency, south Sulawesi Province, Indonesia. Flavonoid and non-flavonoid extracts were purified from propolis using thin layer chromatography. The study was applied on 80 male Sprague Dawley rats, 10–12 weeks of age, divided randomly and equally into 5 groups. Group I, as negative control group was not conducted any treatment. At group II, III, IV and V. A Class I cavity (Black Classification were made on the occlusal surface of right maxillary first molar. The dental pulp was perforated using dental explorer and allowed in the oral environment for 1 h, after that, Ethanolic Extract Propolis (EEP (Group II, Extract Flavonoid-Propolis (EFP (Group III, Extract Non-Flavonoid Propolis (ENFP (Group IV, or Calcium Hydroxide (Ca(OH2 (Group V were applied on dental pulp. All cavities were then filled with Glass Ionomer Cement as permanent filling. The rats being sacrificed in 6 h, 2 days, 4 days and 7 days. Sample biopsy were obtained, IL-6 expression was detected by using immunohistochemistry method. Data was analyzed statistically using

  20. Interleukin-6 expression on inflamed rat dental pulp tissue after capped withTrigonasp. propolis from south Sulawesi, Indonesia.

    Science.gov (United States)

    Sabir, Ardo; Sumidarti, Andi

    2017-07-01

    Background: Propolis is a natural product of plant resins collected by honeybees from various plant sources. It is used as a remedy in folk medicine since ancient times because of its several biological and pharmacological properties. Recently, propolis has been used by dentist to treat various oral diseases. It was always mentioned as an anti-inflammatory agent. Cytokines are proteins that provide communication between cells and play a critical role in a wide variety of processes. It released from cells in an inflammatory process that active, mediate or potential actions of other cells or tissues. When dental pulp has inflammation, several pro-inflammatory cytokines including Interleukin-6 (IL-6) was released by innate immune cells. Objective: To analyse the expression of IL-6 on inflamed rat dental pulp tissue following application of propolis. Material and methods: Trigona sp. propolis was obtained from Luwu Regency, south Sulawesi Province, Indonesia. Flavonoid and non-flavonoid extracts were purified from propolis using thin layer chromatography. The study was applied on 80 male Sprague Dawley rats, 10-12 weeks of age, divided randomly and equally into 5 groups. Group I, as negative control group was not conducted any treatment. At group II, III, IV and V. A Class I cavity (Black Classification) were made on the occlusal surface of right maxillary first molar. The dental pulp was perforated using dental explorer and allowed in the oral environment for 1 h, after that, Ethanolic Extract Propolis (EEP) (Group II), Extract Flavonoid-Propolis (EFP) (Group III), Extract Non-Flavonoid Propolis (ENFP) (Group IV), or Calcium Hydroxide (Ca(OH) 2 ) (Group V) were applied on dental pulp. All cavities were then filled with Glass Ionomer Cement as permanent filling. The rats being sacrificed in 6 h, 2 days, 4 days and 7 days. Sample biopsy were obtained, IL-6 expression was detected by using immunohistochemistry method. Data was analyzed statistically using Freidman

  1. Dental Calculus Stimulates Interleukin-1β Secretion by Activating NLRP3 Inflammasome in Human and Mouse Phagocytes.

    Science.gov (United States)

    Montenegro Raudales, Jorge Luis; Yoshimura, Atsutoshi; Sm, Ziauddin; Kaneko, Takashi; Ozaki, Yukio; Ukai, Takashi; Miyazaki, Toshihiro; Latz, Eicke; Hara, Yoshitaka

    2016-01-01

    Dental calculus is a mineralized deposit associated with periodontitis. The bacterial components contained in dental calculus can be recognized by host immune sensors, such as Toll-like receptors (TLRs), and induce transcription of proinflammatory cytokines, such as IL-1β. Studies have shown that cellular uptake of crystalline particles may trigger NLRP3 inflammasome activation, leading to the cleavage of the IL-1β precursor to its mature form. Phagocytosis of dental calculus in the periodontal pocket may therefore lead to the secretion of IL-1β, promoting inflammatory responses in periodontal tissues. However, the capacity of dental calculus to induce IL-1β secretion in human phagocytes has not been explored. To study this, we stimulated human polymorphonuclear leukocytes (PMNs) and peripheral blood mononuclear cells (PBMCs) with dental calculus collected from periodontitis patients, and measured IL-1β secretion by ELISA. We found that calculus induced IL-1β secretion in both human PMNs and PBMCs. Calculus also induced IL-1β in macrophages from wild-type mice, but not in macrophages from NLRP3- and ASC-deficient mice, indicating the involvement of NLRP3 and ASC. IL-1β induction was inhibited by polymyxin B, suggesting that LPS is one of the components of calculus that induces pro-IL-1β transcription. To analyze the effect of the inorganic structure, we baked calculus at 250°C for 1 h. This baked calculus failed to induce pro-IL-1β transcription. However, it did induce IL-1β secretion in lipid A-primed cells, indicating that the crystalline structure of calculus induces inflammasome activation. Furthermore, hydroxyapatite crystals, a component of dental calculus, induced IL-1β in mouse macrophages, and baked calculus induced IL-1β in lipid A-primed human PMNs and PBMCs. These results indicate that dental calculus stimulates IL-1β secretion via NLRP3 inflammasome in human and mouse phagocytes, and that the crystalline structure has a partial role in

  2. Dental Calculus Stimulates Interleukin-1β Secretion by Activating NLRP3 Inflammasome in Human and Mouse Phagocytes.

    Directory of Open Access Journals (Sweden)

    Jorge Luis Montenegro Raudales

    Full Text Available Dental calculus is a mineralized deposit associated with periodontitis. The bacterial components contained in dental calculus can be recognized by host immune sensors, such as Toll-like receptors (TLRs, and induce transcription of proinflammatory cytokines, such as IL-1β. Studies have shown that cellular uptake of crystalline particles may trigger NLRP3 inflammasome activation, leading to the cleavage of the IL-1β precursor to its mature form. Phagocytosis of dental calculus in the periodontal pocket may therefore lead to the secretion of IL-1β, promoting inflammatory responses in periodontal tissues. However, the capacity of dental calculus to induce IL-1β secretion in human phagocytes has not been explored. To study this, we stimulated human polymorphonuclear leukocytes (PMNs and peripheral blood mononuclear cells (PBMCs with dental calculus collected from periodontitis patients, and measured IL-1β secretion by ELISA. We found that calculus induced IL-1β secretion in both human PMNs and PBMCs. Calculus also induced IL-1β in macrophages from wild-type mice, but not in macrophages from NLRP3- and ASC-deficient mice, indicating the involvement of NLRP3 and ASC. IL-1β induction was inhibited by polymyxin B, suggesting that LPS is one of the components of calculus that induces pro-IL-1β transcription. To analyze the effect of the inorganic structure, we baked calculus at 250°C for 1 h. This baked calculus failed to induce pro-IL-1β transcription. However, it did induce IL-1β secretion in lipid A-primed cells, indicating that the crystalline structure of calculus induces inflammasome activation. Furthermore, hydroxyapatite crystals, a component of dental calculus, induced IL-1β in mouse macrophages, and baked calculus induced IL-1β in lipid A-primed human PMNs and PBMCs. These results indicate that dental calculus stimulates IL-1β secretion via NLRP3 inflammasome in human and mouse phagocytes, and that the crystalline structure has a

  3. Influence of different types of pulp treatment during isolation in the obtention of human dental pulp stem cells

    OpenAIRE

    Viña Almunia, José; Borrás Blasco, Consuelo; Gambini Ricapa, Juan; El Alami, Marya; Peñarrocha Diago, Miguel; Viña Ribes, José

    2016-01-01

    Background Different methods have been used in order to isolate dental pulp stem cells. The aim of this study was to study the effect of different types of pulp treatment during isolation, under 3% O2 conditions, in the time needed and the efficacy for obtaining dental pulp stem cells. Material and Methods One hundred and twenty dental pulps were used to isolate dental pulp stem cells treating the pulp tissue during isolation using 9 different methods, using digestive, disgregation, or mechan...

  4. Novel approach for transient protein expression in primary cultures of human dental pulp-derived cells.

    Science.gov (United States)

    Suguro, Hisashi; Mikami, Yoshikazu; Koshi, Rieko; Ogiso, Bunnai; Watanabe, Eri; Watanabe, Nobukazu; Honda, Masaki J; Asano, Masatake; Komiyama, Kazuo

    2011-08-01

    Transfection is a powerful method for investigating variable biological functions of desired genes. However, the efficiency of transfection into primary cultures of dental pulp-derived cells (DPDC) is low. Therefore, using a recombinant vaccinia virus (vTF7-3), which contains T7 RNA polymerase, we have established a transient protein expression system in DPDCs. In this study, we used the human polymeric immunoglobulin receptor (pIgR) cDNA as a model gene. pIgR expression by the vTF7-3 expression system was confirmed by flow cytometry analysis and Western blotting. Furthermore, exogenous pIgR protein localized at the cell surface in DPDCs and formed a secretory component (SC). This suggests that exogenous pIgR protein expressed by the vTF7-3 expression system acts like endogenous pIgR protein. These results indicate the applicability of the method for cells outgrown from dental pulp tissue. In addition, as protein expression could be detected shortly after transfection (approximately 5h), this experimental system has been used intensely for experiments examining very early steps in protein exocytosis. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Cellular Responses in Human Dental Pulp Stem Cells Treated with Three Endodontic Materials

    Directory of Open Access Journals (Sweden)

    Alejandro Victoria-Escandell

    2017-01-01

    Full Text Available Human dental pulp stem cells (HDPSCs are of special relevance in future regenerative dental therapies. Characterizing cytotoxicity and genotoxicity produced by endodontic materials is required to evaluate the potential for regeneration of injured tissues in future strategies combining regenerative and root canal therapies. This study explores the cytotoxicity and genotoxicity mediated by oxidative stress of three endodontic materials that are widely used on HDPSCs: a mineral trioxide aggregate (MTA-Angelus white, an epoxy resin sealant (AH-Plus cement, and an MTA-based cement sealer (MTA-Fillapex. Cell viability and cell death rate were assessed by flow cytometry. Oxidative stress was measured by OxyBlot. Levels of antioxidant enzymes were evaluated by Western blot. Genotoxicity was studied by quantifying the expression levels of DNA damage sensors such as ATM and RAD53 genes and DNA damage repair sensors such as RAD51 and PARP-1. Results indicate that AH-Plus increased apoptosis, oxidative stress, and genotoxicity markers in HDPSCs. MTA-Fillapex was the most cytotoxic oxidative stress inductor and genotoxic material for HDPSCs at longer times in preincubated cell culture medium, and MTA-Angelus was less cytotoxic and genotoxic than AH-Plus and MTA-Fillapex at all times assayed.

  6. Capacity of Human Dental Follicle Cells to Differentiate into Neural Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Shingo Kanao

    2017-01-01

    Full Text Available The dental follicle is an ectomesenchymal tissue surrounding the developing tooth germ. Human dental follicle cells (hDFCs have the capacity to commit to differentiation into multiple cell types. Here we investigated the capacity of hDFCs to differentiate into neural cells and the efficiency of a two-step strategy involving floating neurosphere-like bodies for neural differentiation. Undifferentiated hDFCs showed a spindle-like morphology and were positive for neural markers such as nestin, β-III-tubulin, and S100β. The cellular morphology of several cells was neuronal-like including branched dendrite-like processes and neurites. Next, hDFCs were used for neurosphere formation in serum-free medium containing basic fibroblast growth factor, epidermal growth factor, and B27 supplement. The number of cells with neuronal-like morphology and that were strongly positive for neural markers increased with sphere formation. Gene expression of neural markers also increased in hDFCs with sphere formation. Next, gene expression of neural markers was examined in hDFCs during neuronal differentiation after sphere formation. Expression of Musashi-1 and Musashi-2, MAP2, GFAP, MBP, and SOX10 was upregulated in hDFCs undergoing neuronal differentiation via neurospheres, whereas expression of nestin and β-III-tubulin was downregulated. In conclusion, hDFCs may be another optimal source of neural/glial cells for cell-based therapies to treat neurological diseases.

  7. A Comparison of Culture Characteristics between Human Amniotic Mesenchymal Stem Cells and Dental Stem Cells.

    Science.gov (United States)

    Yusoff, Nurul Hidayat; Alshehadat, Saaid Ayesh; Azlina, Ahmad; Kannan, Thirumulu Ponnuraj; Hamid, Suzina Sheikh Abdul

    2015-04-01

    In the past decade, the field of stem cell biology is of major interest among researchers due to its broad therapeutic potential. Stem cells are a class of undifferentiated cells that are able to differentiate into specialised cell types. Stem cells can be classified into two main types: adult stem cells (adult tissues) and embryonic stem cells (embryos formed during the blastocyst phase of embryological development). This review will discuss two types of adult mesenchymal stem cells, dental stem cells and amniotic stem cells, with respect to their differentiation lineages, passage numbers and animal model studies. Amniotic stem cells have a greater number of differentiation lineages than dental stem cells. On the contrary, dental stem cells showed the highest number of passages compared to amniotic stem cells. For tissue regeneration based on animal studies, amniotic stem cells showed the shortest time to regenerate in comparison with dental stem cells.

  8. Human Cell and Tissue Establishment Registration Public Query

    Data.gov (United States)

    U.S. Department of Health & Human Services — This application provides Human Cell and Tissue registration information for registered, inactive, and pre-registered firms. Query options are by Establishment Name,...

  9. Expression of Ecto-ATPase NTPDase2 in Human Dental Pulp

    Science.gov (United States)

    Yu, L.; Wang, Q.; Pelletier, J.; Fausther, M.; Sévigny, J.; Malmström, H.S.; Dirksen, R.T.; Ren, Y.-F.

    2012-01-01

    Dental pulpal nerve fibers express ionotropic adenosine triphosphate (ATP) receptors, suggesting that ATP signaling participates in the process of dental nociception. In this study, we investigated if the principal enzymes responsible for extracellular ATP hydrolysis, namely, nucleoside triphosphate diphosphohydrolases (NTPDases), are present in human dental pulp. Immunohistochemical and immunofluorescence experiments showed that NTPDase2 was predominantly expressed in pulpal nerve bundles, Raschkow’s nerve plexus, and in the odontoblast layer. NTPDase2 was expressed in pulpal Schwann cells, with processes accompanying the nerve fibers and projecting into the odontoblast layer. Odontoblasts expressed the gap junction protein, connexin43, which can form transmembrane hemichannels for ATP release. NTPDase2 was localized close to connexin43 within the odontoblast layer. These findings provide evidence for the existence of an apparatus for ATP release and degradation in human dental pulp, consistent with the involvement of ATP signaling in the process of dentin sensitivity and dental pain. PMID:22173326

  10. The effect of TRPM7 suppression on the proliferation, migration and osteogenic differentiation of human dental pulp stem cells.

    Science.gov (United States)

    Cui, L; Xu, S M; Ma, D D; Wu, B L

    2014-06-01

    To investigate the role of the Ca(2+) -Mg(2+) ion channel TRPM7 in the proliferation, migration and osteogenic differentiation of human dental pulp stem cells (hDPSCs). Immunohistochemistry was used to localize expression of TRPM7 in human dental pulp tissues and in cultured hDPSCs. Isolated hDPSCs were infected with recombinant lentiviruses expressing short hairpin RNA (shRNA) specific for TRPM7, or control shRNA, in order to suppress TRPM7 mRNA expression and investigate its functional role. The proliferation of the shRNA-infected hDPSCs was evaluated using both an MTT assay to measure viable cell numbers and cell cycle analysis. Cell migration was assessed using a transwell assay. The dynamic mRNA expression of TRPM7 during osteogenic differentiation of hDPSCs and the effect of shRNA specific for TRPM7 on hDPSC osteogenic differentiation were evaluated by real-time PCR. TRPM7 expression was widespread in human dental pulp tissue and was detected mainly in the cytomembrane and cytoplasm of hDPSCs. Suppression of TRPM7 inhibited both the proliferation and the migratory capacity of hDPSCs. TRPM7 mRNA expression was elevated during osteogenic differentiation of hDPSCs. TRPM7-specific shRNA inhibited osteogenic differentiation of hDPSCs, with downregulated mRNA expression of the osteogenic markers alkaline phosphatase (ALP), dentine sialophosphoprotein (DSPP), bone sialoprotein (BSP), runt-related transcription factor (RUNX2) and osterix (OSX). TRPM7 was involved in the regulation of hDPSC proliferation, migration and osteogenic differentiation and may play a role in the dental pulp repair process. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  11. Passive immunization against dental caries and periodontal disease: development of recombinant and human monoclonal antibodies.

    Science.gov (United States)

    Abiko, Y

    2000-01-01

    Indigenous micro-organisms in the oral cavity can cause two major diseases, dental caries and periodontal diseases. There is neither agreement nor consensus as to the actual mechanisms of pathogenesis of the specific virulence factors of these micro-organisms. The complexity of the bacterial community in dental plaque has made it difficult for the single bacterial agent of dental caries to be determined. However, there is considerable evidence that Streptococcus mutans is implicated as the primary causative organism of dental caries, and the cell-surface protein antigen (SA I/II) as well as glucosyltransferases (GTFs) produced by S. mutans appear to be major colonization factors. Various forms of periodontal diseases are closely associated with specific subgingival bacteria. Porphyromonas gingivalis has been implicated as an important etiological agent of adult periodontitis. Adherence of bacteria to host tissues is a prerequisite for colonization and one of the important steps in the disease process. Bacterial coaggregation factors and hemagglutinins likely play major roles in colonization in the subgingival area. Emerging evidence suggests that inhibition of these virulence factors may protect the host against caries and periodontal disease. Active and passive immunization approaches have been developed for immunotherapy of these diseases. Recent advances in mucosal immunology and the introduction of novel strategies for inducing mucosal immune responses now raise the possibility that effective and safe vaccines can be constructed. In this regard, some successful results have been reported in animal experimental models. Nevertheless, since the public at large might be skeptical about the seriousness of oral diseases, immunotherapy must be carried out with absolute safety. For this goal to be achieved, the development of safe antibodies for passive immunization is significant and important. In this review, salient advances in passive immunization against caries

  12. The use of animal tissues alongside human tissue: Cultural and ethical considerations.

    Science.gov (United States)

    Kaw, Anu; Jones, D Gareth; Zhang, Ming

    2016-01-01

    Teaching and research facilities often use cadaveric material alongside animal tissues, although there appear to be differences in the way we handle, treat, and dispose of human cadaveric material compared to animal tissue. This study sought to analyze cultural and ethical considerations and provides policy recommendations on the use of animal tissues alongside human tissue. The status of human and animal remains and the respect because of human and animal tissues were compared and analyzed from ethical, legal, and cultural perspectives. The use of animal organs and tissues is carried out within the context of understanding human anatomy and function. Consequently, the interests of human donors are to be pre-eminent in any policies that are enunciated, so that if any donors find the presence of animal remains unacceptable, the latter should not be employed. The major differences appear to lie in differences in our perceptions of their respective intrinsic and instrumental values. Animals are considered to have lesser intrinsic value and greater instrumental value than humans. These differences stem from the role played by culture and ethical considerations, and are manifested in the resulting legal frameworks. In light of this discussion, six policy recommendations are proposed, encompassing the nature of consent, respect for animal tissues as well as human remains, and appropriate separation of both sets of tissues in preparation and display. © 2015 Wiley Periodicals, Inc.

  13. Data Fitting to Study Ablated Hard Dental Tissues by Nanosecond Laser Irradiation.

    Directory of Open Access Journals (Sweden)

    Y Al-Hadeethi

    Full Text Available Laser ablation of dental hard tissues is one of the most important laser applications in dentistry. Many works have reported the interaction of laser radiations with tooth material to optimize laser parameters such as wavelength, energy density, etc. This work has focused on determining the relationship between energy density and ablation thresholds using pulsed, 5 nanosecond, neodymium-doped yttrium aluminum garnet; Nd:Y3Al5O12 (Nd:YAG laser at 1064 nanometer. For enamel and dentin tissues, the ablations have been performed using laser-induced breakdown spectroscopy (LIBS technique. The ablation thresholds and relationship between energy densities and peak areas of calcium lines, which appeared in LIBS, were determined using data fitting. Furthermore, the morphological changes were studied using Scanning Electron Microscope (SEM. Moreover, the chemical stability of the tooth material after ablation has been studied using Energy-Dispersive X-Ray Spectroscopy (EDX. The differences between carbon atomic % of non-irradiated and irradiated samples were tested using statistical t-test. Results revealed that the best fitting between energy densities and peak areas of calcium lines were exponential and linear for enamel and dentin, respectively. In addition, the ablation threshold of Nd:YAG lasers in enamel was higher than that of dentin. The morphology of the surrounded ablated region of enamel showed thermal damages. For enamel, the EDX quantitative analysis showed that the atomic % of carbon increased significantly when laser energy density increased.

  14. Data Fitting to Study Ablated Hard Dental Tissues by Nanosecond Laser Irradiation.

    Science.gov (United States)

    Al-Hadeethi, Y; Al-Jedani, S; Razvi, M A N; Saeed, A; Abdel-Daiem, A M; Ansari, M Shahnawaze; Babkair, Saeed S; Salah, Numan A; Al-Mujtaba, A

    2016-01-01

    Laser ablation of dental hard tissues is one of the most important laser applications in dentistry. Many works have reported the interaction of laser radiations with tooth material to optimize laser parameters such as wavelength, energy density, etc. This work has focused on determining the relationship between energy density and ablation thresholds using pulsed, 5 nanosecond, neodymium-doped yttrium aluminum garnet; Nd:Y3Al5O12 (Nd:YAG) laser at 1064 nanometer. For enamel and dentin tissues, the ablations have been performed using laser-induced breakdown spectroscopy (LIBS) technique. The ablation thresholds and relationship between energy densities and peak areas of calcium lines, which appeared in LIBS, were determined using data fitting. Furthermore, the morphological changes were studied using Scanning Electron Microscope (SEM). Moreover, the chemical stability of the tooth material after ablation has been studied using Energy-Dispersive X-Ray Spectroscopy (EDX). The differences between carbon atomic % of non-irradiated and irradiated samples were tested using statistical t-test. Results revealed that the best fitting between energy densities and peak areas of calcium lines were exponential and linear for enamel and dentin, respectively. In addition, the ablation threshold of Nd:YAG lasers in enamel was higher than that of dentin. The morphology of the surrounded ablated region of enamel showed thermal damages. For enamel, the EDX quantitative analysis showed that the atomic % of carbon increased significantly when laser energy density increased.

  15. Necessity of keratinized tissues for dental implants: a clinical, immunological, and radiographic study.

    Science.gov (United States)

    Buyukozdemir Askin, Sezen; Berker, Ezel; Akincibay, Hakan; Uysal, Serdar; Erman, Baran; Tezcan, İlhan; Karabulut, Erdem

    2015-02-01

    Necessity of keratinized tissues (KTs) for maintaining health around dental implants (DIs) remains as a controversial issue. The aim of this study was to investigate the effects of KT width (KTW) on peri-implant tissues by evaluating peri-implant clinical and inflammatory parameters. Sixty DIs were included in this 6-month longitudinal study. After classifying DI based on the presence of KTs at the buccal aspect as with adequate/inadequate KTW, DIs were randomly assigned into three study groups. In the first group, while free gingival graft (FGG) was performed, DIs in maintenance (M) group were followed up by standardized maintenance procedures at baseline, first, third, and sixth months as with DI with adequate KTW (Control). Clinical parameters, peri-implant sulcular fluid (PISF) volume, PISF Interleukin 1β concentration, and bone loss were analyzed. Significant improvements in clinical and immunological parameters were noted only for FGG for the whole study period. Statistical differences detected between the treatment groups (FGG vs M) were for gingival index at all time points and for PISF volume at sixth month. For the other parameters evaluated, while lower values were observed for FGG, statistically no differences were noted between the groups. Based on the results of this study, it can be suggested that FGG performed around DIs lacking KT is a reliable method, leading to significant improvements in clinical and inflammatory parameters. Further long-term studies including more DIs are needed to clarify the role of KT on maintenance of DIs. © 2013 Wiley Periodicals, Inc.

  16. Local aromatase activity in human breast tissues.

    Science.gov (United States)

    Thijssen, J H; Daroszewski, J; Milewicz, A; Blankenstein, M A

    1993-03-01

    The presence of oestradiol in malignant breast cells is considered to be an important factor in the promotion of growth of the tumor. Therefore the regulation of the local high intra-tissue oestradiol concentrations, regardless of plasma concentrations, has been investigated. Experimental evidence suggests that in situ biosynthesis of oestrogens is at least partly responsible for the local accumulation of these steroids. In this paper we report further data on measurements in fatty and tumor tissues of local aromatase activities and of concentrations of substrates and products of this enzyme. Data are given on localization of aromatase and on steroid concentrations in tumors and in adipose tissues dissected from different quadrants of breasts with malignant tumors. In adipose tissues small variations in steroid concentrations in fatty tissues were found. No tumor-directed gradients in the adipose tissue-concentrations of the androgens dehydro-epiandrosterone, 5-androstene-3 beta, 17 beta-diol, 4-androstene-3,17-dione and testosterone and of the oestrogens oestradiol, oestrone and their sulfates could be detected. Furthermore no consistent pattern could be recognized in the aromatase activities in the fatty tissues dissected from tumor-bearing and non-affected quadrants of the same breast. No correlations between aromatase activity measured in vitro and product concentrations in vivo were found. Therefore the mechanisms for regulation of the local oestradiol levels in breast tissues remain unknown.

  17. Ceftibuten concentrations in human tonsillar tissue.

    Science.gov (United States)

    Scaglione, F; Pintucci, J P; Demartini, G; Dugnani, S

    1996-12-01

    In a study designed to determine ceftibuten concentrations in tonsillar tissue, subjects scheduled to undergo tonsillectomy were administered 400 mg of ceftibuten in a single oral dose. Between 2 and 24 h after the dose was given, tonsillar tissue samples were taken during surgery and assayed for ceftibuten. Mean concentrations in tonsillar tissue 4.4 h and 24.6 h after the 400 mg dose were 5.3 +/- 2.7 and 0.3 +/- mg/g, respectively. Concurrent mean serum concentrations were 7.42 +/- 1.66 and 0.15 +/- 0.13 mg/ml, respectively. The apparent half-life of drug in the tissue was 5.3 h. The presence of high ceftibuten concentrations in tonsillar tissue suggests that a once-daily regimen may be effective in treating tonsillitis and pharyngitis.

  18. Human Adult Dental Pulp Stem Cells Enhance Poststroke Functional Recovery Through Non‐Neural Replacement Mechanisms

    National Research Council Canada - National Science Library

    Leong, Wai Khay; Henshall, Tanya L; Arthur, Agnes; Kremer, Karlea L; Lewis, Martin D; Helps, Stephen C; Field, John; Hamilton-Bruce, Monica A; Warming, Scott; Manavis, Jim; Vink, Robert; Gronthos, Stan; Koblar, Simon A

    2012-01-01

    Human adult dental pulp stem cells (DPSCs), derived from third molar teeth, are multipotent and have the capacity to differentiate into neurons under inductive conditions both in vitro and following transplantation into the avian embryo...

  19. Dental caries vaccine.

    Science.gov (United States)

    Shivakumar, K M; Vidya, S K; Chandu, G N

    2009-01-01

    Dental caries is one of the most common diseases in humans. In modern times, it has reached epidemic proportions. Dental caries is an infectious microbiologic disease of the teeth that results in localized dissolution and destruction of the calcified tissue. Dental caries is a mulitifactorial disease, which is caused by host, agent, and environmental factors. The time factor is important for the development and progression of dental caries. A wide group of microorganisms are identified from carious lesions of which S. mutans , Lactobacillus acidophilus , and Actinomyces viscosus are the main pathogenic species involved in the initiation and development of dental caries. In India, surveys done on school children showed caries prevalence of approximately 58%. Surveys among the U.S. population showed an incidence of 45.3% in children and 93.8% in adults with either past or present coronal caries. Huge amounts of money and time are spent in treating dental caries. Hence, the prevention and control of dental caries is the main aim of public health, eventually the ultimate objective of public health is the elimination of the disease itself. Recently, dental caries vaccines have been developed for the prevention of dental caries. These dental caries vaccines are still in the early stages.

  20. Dental caries vaccine

    Directory of Open Access Journals (Sweden)

    Shivakumar K

    2009-01-01

    Full Text Available Dental caries is one of the most common diseases in humans. In modern times, it has reached epidemic proportions. Dental caries is an infectious microbiologic disease of the teeth that results in localized dissolution and destruction of the calcified tissue. Dental caries is a mulitifactorial disease, which is caused by host, agent, and environmental factors. The time factor is important for the development and progression of dental caries. A wide group of microorganisms are identified from carious lesions of which S. mutans , Lactobacillus acidophilus , and Actinomyces viscosus are the main pathogenic species involved in the initiation and development of dental caries. In India, surveys done on school children showed caries prevalence of approximately 58%. Surveys among the U.S. population showed an incidence of 45.3% in children and 93.8% in adults with either past or present coronal caries. Huge amounts of money and time are spent in treating dental caries. Hence, the prevention and control of dental caries is the main aim of public health, eventually the ultimate objective of public health is the elimination of the disease itself. Recently, dental caries vaccines have been developed for the prevention of dental caries. These dental caries vaccines are still in the early stages.

  1. Effect of hydralazine on duration of soft tissue local anesthesia following dental treatment: a randomized clinical trial.

    Science.gov (United States)

    Fakheran Esfahani, Omid; Pouraboutaleb, Mohammad Fazel; Khorami, Behnam

    2015-01-01

    Prolonged numbness following routine dental treatments can cause difficulties in speaking and swallowing and may result in inadvertent biting of soft tissues. Local injection of vasodilator agents may represent a solution to this problem. The aim of this study was to evaluate the effect of submucosal injection of hydralazine hydrochloride (HCl) on the duration of oral soft tissue anesthesia after routine dental treatment. This randomized, single-blinded, controlled clinical trial included 50 patients who received inferior alveolar nerve block (2% lidocaine with 1:100,000 epinephrine) for simple restorative treatment. Upon completion of the dental treatment, patients randomly received a hydralazine HCl or sham injection in the same site as the local anesthetic injection. The reversal time to normal sensation of soft tissues (lips, tongue, and perioral skin) was evaluated and reported every 5 minutes by the patients, who followed an assessment protocol that they were taught in advance of treatment. Median recovery times in the hydralazine group and the sham group were 81.4 (SD, 3.6) and 221.8 (SD, 6.3) minutes, respectively. Based on Kaplan-Meier survival analysis, the duration of soft tissue anesthesia in the 2 groups was significantly different (P local anesthetic-induced soft tissue numbness and the related functional problems.

  2. Human tissue legislation in South Africa: Focus on stem cell ...

    African Journals Online (AJOL)

    2015-08-04

    Aug 4, 2015 ... under the Human Tissue Act 65 of 1983, which was repealed with the enactment of the final sections of the NHA in 2012.[5]. Chapter 8 of the NHA covers seven areas that are relevant to human tissues. These include: • Blood and blood products. • Assisted reproductive technology. • Cell-based therapy.

  3. Partial relief from the regulatory vacuum involving human tissues ...

    African Journals Online (AJOL)

    Human tissue legislation in South. Africa. Concerning human tissue legislation, the law has traditionally struggled to match the pace of scientific and technological advances.1. In this respect, the National Health Act2 (NHA) assented to by the. President on 18 July 2004 came into force on 2 May 2005. At that time matters ...

  4. Investigations of the damage mechanisms during ultrashort pulse laser ablation of dental tissue

    Science.gov (United States)

    Domke, Matthias; Wick, Sebastian; Laible, Maike; Rapp, Stephan; Kuznetsova, Julia; Homann, Christian; Huber, Heinz P.; Sroka, Ronald

    2015-07-01

    Several investigations of dental tissue ablation with ultrashort pulsed lasers suggest that these lasers enable precise and selective material removal and reduce the formation of micro cracks and thermal effects, when compared to ns-pulses. In this study, two damage mechanisms are presented occurring during ablation of dentin using a laser emitting pulses of a duration of 380 fs at a wavelength of 1040 nm. First, it was found that nano cracks appear around the craters after single fs-pulse ablation. These cracks are directed to the crater and cross the dentinal tubules. Transient investigation of the single fs-pulse ablation process by pump-probe microscopy suggest that the driving mechanism could be a pressure wave that is released after stress confinement. Second, squared ablation holes were created by moving the laser focus at scan speeds between 0.5 mm/s and 2.0 m/s and fluences up to 14 J/cm2. It was found that deep cracks appear at the edges of the squared holes, if the scan speed is about 0.5 m/s. The fluence has only a minor impact on the crack formation. The crack propagation was investigated in the depth using x-ray micro tomography and optical coherence tomography. It was found that these cracks appear in the depth down to the dental pulp. These findings suggest that fast scanning of the laser beam is the key for damage free processing using ultrashort pulse lasers. Then, ablation rates of about 2.5 - 3.5 mm3/min/W can be achieved in dentine with pulse durations of 380 fs.

  5. Mesenchymal stem cells derived from inflamed dental pulpal and gingival tissue: a potential application for bone formation.

    Science.gov (United States)

    Tomasello, Laura; Mauceri, Rodolfo; Coppola, Antonina; Pitrone, Maria; Pizzo, Giuseppe; Campisi, Giuseppina; Pizzolanti, Giuseppe; Giordano, Carla

    2017-08-01

    Chronic periodontal disease is an infectious disease consisting of prolonged inflammation of the supporting tooth tissue and resulting in bone loss. Guided bone regeneration procedures have become common and safe treatments in dentistry, and in this context dental stem cells would represent the ideal solution as autologous cells. In this study, we verified the ability of dental pulp mesenchymal stem cells (DPSCs) and gingival mesenchymal stem cells (GMSCs) harvested from periodontally affected teeth to produce new mineralized bone tissue in vitro, and compared this to cells from healthy teeth. To characterize DPSCs and GMSCs, we assessed colony-forming assay, immunophenotyping, mesenchymal/stem cell phenotyping, stem gene profiling by means of flow cytometry, and quantitative polymerase chain reaction (qPCR). The effects of proinflammatory cytokines on mesenchymal stem cell (MSC) proliferation and differentiation potential were investigated. We also observed participation of several heat shock proteins (HSPs) and actin-depolymerizing factors (ADFs) during osteogenic differentiation. DPSCs and GMSCs were successfully isolated both from periodontally affected dental tissue and controls. Periodontally affected dental MSCs proliferated faster, and the inflamed environment did not affect MSC marker expressions. The calcium deposition was higher in periodontally affected MSCs than in the control group. Proinflammatory cytokines activate a cytoskeleton remodeling, interacting with HSPs including HSP90 and HSPA9, thioredoxin-1, and ADFs such as as profilin-1, cofilin-1, and vinculin that probably mediate the increased acquisition in the inflamed environment. Our findings provide evidence that periodontally affected dental tissue (both pulp and gingiva) can be used as a source of MSCs with intact stem cell properties. Moreover, we demonstrated that the osteogenic capability of DPSCs and GMSCs in the test group was not only preserved but increased by the overexpression of

  6. Transplantation of Human Dental Pulp-Derived Stem Cells or Differentiated Neuronal Cells from Human Dental Pulp-Derived Stem Cells Identically Enhances Regeneration of the Injured Peripheral Nerve.

    Science.gov (United States)

    Ullah, Imran; Park, Ju-Mi; Kang, Young-Hoon; Byun, June-Ho; Kim, Dae-Geon; Kim, Joo-Heon; Kang, Dong-Ho; Rho, Gyu-Jin; Park, Bong-Wook

    2017-09-01

    Human dental mesenchymal stem cells isolated from the dental follicle, pulp, and root apical papilla of extracted wisdom teeth have been known to exhibit successful and potent neurogenic differentiation capacity. In particular, human dental pulp-derived stem cells (hDPSCs) stand out as the most prominent source for in vitro neuronal differentiation. In this study, to evaluate the in vivo peripheral nerve regeneration potential of hDPSCs and differentiated neuronal cells from DPSCs (DF-DPSCs), a total of 1 × 106 hDPSCs or DF-hDPSCs labeled with PKH26 tracking dye and supplemented with fibrin glue scaffold and collagen tubulization were transplanted into the sciatic nerve resection (5-mm gap) of rat models. At 12 weeks after cell transplantation, both hDPSC and DF-hDPSC groups showed notably increased behavioral activities and higher muscle contraction forces compared with those in the non-cell transplanted control group. In immunohistochemical analysis of regenerated nerve specimens, specific markers for angiogenesis, axonal fiber, and myelin sheath increased in both the cell transplantation groups. Pretransplanted labeled PKH26 were also distinctly detected in the regenerated nerve tissues, indicating that transplanted cells were well-preserved and differentiated into nerve cells. Furthermore, no difference was observed in the nerve regeneration potential between the hDPSC and DF-hDPSC transplanted groups. These results demonstrate that dental pulp tissue is an excellent stem cell source for nerve regeneration, and in vivo transplantation of the undifferentiated hDPSCs could exhibit sufficient and excellent peripheral nerve regeneration potential.

  7. Lipolysis in human adipose tissue during exercise

    DEFF Research Database (Denmark)

    Lange, Kai Henrik Wiborg; Lorentsen, Jeanne; Isaksson, Fredrik

    2002-01-01

    Subcutaneous adipose tissue lipolysis was studied in vivo by Fick's arteriovenous (a-v) principle using either calculated (microdialysis) or directly measured (catheterization) adipose tissue venous glycerol concentration. We compared results during steady-state (rest and prolonged continuous...... exercise), as well as during non-steady-state (onset of exercise and early exercise) experimental settings. Fourteen healthy women [age: 74 +/- 1 (SE) yr] were studied at rest and during 60-min continuous bicycling at 60% of peak O(2) uptake. Calculated and measured subcutaneous abdominal adipose tissue...

  8. Human Dental Pulp Stem Cells Improve Left Ventricular Function, Induce Angiogenesis, and Reduce Infarct Size in Rats with Acute Myocardial Infarction

    National Research Council Canada - National Science Library

    Gandia, Carolina; Armiñan, Ana; García‐Verdugo, Jose Manuel; Lledó, Elisa; Ruiz, Amparo; Miñana, M Dolores; Sanchez‐Torrijos, Jorge; Payá, Rafael; Mirabet, Vicente; Carbonell‐Uberos, Francisco; Llop, Mauro; Montero, Jose Anastasio; Sepúlveda, Pilar

    2008-01-01

    Human dental pulp contains precursor cells termed dental pulp stem cells (DPSC) that show self‐renewal and multilineage differentiation and also secrete multiple proangiogenic and antiapoptotic factors...

  9. The use of functional human tissues in drug development.

    Science.gov (United States)

    Bunton, David

    2010-12-01

    Drug development currently depends on animal models to provide an accurate prediction of human physiology and pathophysiology. However, as is clear from clinical trial failures during phases II and III, such in vivo models do not always predict the effects that a drug can elicit in humans. Tests with human tissues, which are obviously considered to be the closest model of human in vivo function, could fill the gap between animal-based tests and trials in patients. Despite clear advantages, logistical and ethical barriers prevent fresh human tissues from being widely used during drug development. Biopta is aiming to make human tissue testing a regular element of drug development, and works to lower the barriers surrounding the availability of tissue and practicalities of experimental work. 2010 FRAME.

  10. Optimization of treatment with recombinant FGF-2 for proliferation and differentiation of human dental stem cells, mesenchymal stem cells, and osteoblasts.

    Science.gov (United States)

    Lee, Tae-Hyung; Kim, Won-Tae; Ryu, Chun Jeih; Jang, Young-Joo

    2015-08-01

    Basic fibroblast growth factor (bFGF or FGF-2) is widely used to modulate the proliferation and differentiation of certain cell types. An expression and purification system for recombinant human FGF-2 in Escherichia coli was established for the purpose of securing a continuous supply of this protein. The purified recombinant FGF-2 significantly increased the population of human embryonic stem cells. The optimal concentrations of FGF-2 for cell proliferative induction in various adult stem cells including human dental pulp stem cells, full term human periodontal ligament stem cells, human gingival fibroblasts, mesenchymal stem cells, and osteogenic oseosarcoma were established in a dose-dependent manner. When cells were treated with recombinant FGF-2 for 6 days before osteogenic induction, the mRNA expression of the bone markers was upregulated in cells originated from human dental pulp tissue, indicating that pretreatment with FGF-2 during culture increase stem cell/progenitor population and osteogenic potential.

  11. Isolation and morphology of Stem Cells from Deciduous Tooth (SHED) and Human Dental Pulp Stem Cells (hDPSC)

    Science.gov (United States)

    Ariffin, Shahrul Hisham Zainal; Manogaran, Thanaletchumi; Abidin, Intan Zarina Zainol; Senafi, Sahidan; Wahab, Rohaya Megat Abdul

    2016-11-01

    Dental pulp is a tissue obtained from pulp chamber of deciduous and permanent tooth which contain stem cells. Stem cell isolation procedure is performed to obtain cells from tissue using enzymatic digestion. The aim of this study is to isolate and observe the morphology of stem cells during passage 0 and passage 3. Dental pulp from deciduous and permanent tooth was enzymatically digested using collagenase Type I and cells obtained were cultured in DMEM-KO that contains 10% fetal bovine serum, 1% antibiotic-antimycotic solution and 0.001× GlutaMax®. During culture, cell morphology was observed under the microscope on day 3, 16 and 33 and captured using cellB software. Giemsa staining was conducted on cells at passage 3. Cells attached at the bottom of the flask on day 3 and started forming small colonies. Cells became confluent after approximately 4 weeks. Both Stem Cells from Deciduous Tooth (SHED) and Human Dental Pulp Stem Cells (hDPSC) exhibited fibroblast-like morphology during passage 0 and passage 3. Meanwhile, Giemsa staining at passage 3 revealed single intact nucleus surrounded by fibroblastic cytoplasm structure. It can be concluded that SHED and hDPSC showed consistent fibroblast-like morphology throughout culture period.

  12. Evidence of the protein content of bovine and human dental pulps by the action of endodontic irrigation solutions through electrophoretic patterns

    Directory of Open Access Journals (Sweden)

    María E López

    2013-01-01

    Full Text Available Background: Sodium dodecyl sulfate polyacrylamide gel electrophoresis let to show the protein content of different tissues. Dental pulp contains connective tissue which is removed during the endodontic treatment. Many studies consider bovine rather than human pulp tissue because of its size. Aim: To evidence the protein content of bovine and human dental pulps and the action of endodontic irrigation solutions through electrophoretic patterns. Materials and Methods: Extracts of human and bovine dental pulps were prepared. Sodium hypochlorite, calcium hydroxide, chlorhexidine and ethylenediamine tetraacetic acid were used as irrigating solutions. Results: Bovine and human pulps have a small difference in two bands of proteins present between 74 kDa and 80 kDa. The denaturizing capacity of sodium hypochlorite and the washing action of calcium hydroxide and chlorhexidine were evidenced. Ethylenediamine tetraacetic acid solution was shown to contain proteins continuously during the endodontic root canal washing. Conclusions: Differences in pulp tissues and the action of irrigating solutions on their protein content would help on the understanding of the biological process of the endodontic treatment.

  13. A retrospective study on traumatic dental and soft-tissue injuries in preschool children in Zagreb, Croatia.

    Science.gov (United States)

    Vuletić, Marko; Škaričić, Josip; Batinjan, Goran; Trampuš, Zdenko; Čuković Bagić, Ivana; Jurić, Hrvoje

    2014-02-01

    The purpose of this study was to analyze data according to gender, age, cause, number of traumatized teeth, time elapsed before treatment and type of tooth from the records of traumatized children. A retrospective study was conducted in the Department of Paediatric Dentistry at the University Dental Clinic in Zagreb, Croatia using the documentation of 128 patients (61 males and 67 females) aged 1 month to 6 years with injuries of primary teeth between February 2009 and January 2013. Trauma was seen in 217 primary teeth, which implies that the number of injured primary teeth was 1.69 per child. The maxillary central incisors were the most frequently affected teeth (81.1%), they were followed by maxillary lateral incisors, while the least affected were mandibular central incisors. Traumatic dental injuries involved periodontal tissue 2.82 times more frequently than hard dental and pulp tissue. The main cause of teeth injury was fall (67.2%) and the majority of injuries occurred at home (51.6%) (ptissue injuries. The distribution of soft-tissue injuries by gender (35 males, 36 females) was not statistically significant. Comparing children with soft-tissue injuries and those without them, a statistically significant difference was found in the time of arrival (ptrauma injuries.

  14. Humanism in Dental Education: A Comparison of Theory, Intention, and Stakeholder Perceptions at a North American Dental School.

    Science.gov (United States)

    Lyon, Lucinda; Itaya, Lisa E; Hoover, Terry; Booth, Mark T; Nadershahi, Nader

    2017-08-01

    In today's dental education environment, a humanistic culture is an expectation for all U.S. dental schools, codified in 2013 by its inclusion in the Commission on Dental Accreditation's standards for accreditation. The University of the Pacific Arthur A. Dugoni School of Dentistry has made an active commitment to humanism since the mid-1970s. The aim of this study was to determine how well the school's students and faculty and staff members perceived the school was living up to its formal aspirational values and who was benefitting from the humanistic culture. Using an electronic survey, data were collected from a total of 195 students, faculty members, and staff members in 2014. Respondents were 15% of the 492 full- and part-time faculty members; 9% of the total student population of 540; and 29% of 255 staff members. In the responses, humanism was described as manifest by attributes such as caring, understanding, respect, and compassion. Although the findings confirmed the value of a humanistic culture, some portions of the school's formal definition and goals, such as good work ethic, professional responsibility, high ethical standards, increasing independence, and attainment of competence, appeared less frequently in responses. Authentic assessment of institutional culture proved challenging. Focus groups offered additional ways to assess how effectively the school lives its core value of humanism. There was recognition that more varied, robust methods were needed to assess institutional alignment with stated goals for a humanistic learning environment.

  15. A retrospective study on traumatic dental and soft-tissue injuries in preschool children in Zagreb, Croatia

    Directory of Open Access Journals (Sweden)

    Marko Vuletić

    2014-05-01

    Full Text Available The purpose of this study was to analyze data according to gender, age, cause, number of traumatized teeth, time elapsed before treatment and type of tooth from the records of traumatized children. A retrospective study was conducted in the Department of Paediatric Dentistry at the University Dental Clinic in Zagreb, Croatia using the documentation of 128 patients (61 males and 67 females aged 1 month to 6 years with injuries of primary teeth between February 2009 and January 2013. Trauma was seen in 217 primary teeth, which implies that the number of injured primary teeth was 1.69 per child. The maxillary central incisors were the most frequently affected teeth (81.1%, they were followed by maxillary lateral incisors, while the least affected were mandibular central incisors. Traumatic dental injuries involved periodontal tissue 2.82 times more frequently than hard dental and pulp tissue. The main cause of teeth injury was fall (67.2% and the majority of injuriesoccurred at home (51.6% (p<0.05. Of 128 patients who received treatment 71 (55.5% also had soft-tissue injuries. The distribution of soft-tissue injuries by gender (35 males, 36 females was not statistically significant. Comparing children with soft-tissue injuries and those without them, a statistically significant difference was found in the time of arrival (p<0.01. The results of this study showed the need of informing about preventive measures against falls at home and the methods of providing first aid in dental trauma injuries.

  16. A Dental Radiograph Recognition System Using Phase-Only Correlation for Human Identification

    Science.gov (United States)

    Ito, Koichi; Nikaido, Akira; Aoki, Takafumi; Kosuge, Eiko; Kawamata, Ryota; Kashima, Isamu

    In mass disasters such as earthquakes, fire disasters, tsunami, and terrorism, dental records have been used for identifying victims due to their processing time and accuracy. The greater the number of victims, the more time the identification tasks require, since a manual comparison between the dental radiograph records is done by forensic experts. Addressing this problem, this paper presents an efficient dental radiograph recognition system using Phase-Only Correlation (POC) for human identification. The use of phase components in 2D (two-dimensional) discrete Fourier transforms of dental radiograph images makes possible to achieve highly robust image registration and recognition. Experimental evaluation using a set of dental radiographs indicates that the proposed system exhibits efficient recognition performance for low-quality images.

  17. Morphological changes in hard dental tissues prepared by Er:YAG laser (LiteTouch, Syneron), Carisolv and rotary instruments. A scanning electron microscopy evaluation.

    Science.gov (United States)

    Tsanova, Snejana Ts; Tomov, Georgi T

    2010-01-01

    This in vitro investigation aimed to study by means of scanning electron microscope the morphological changes in hard dental tissues after using several different methods for caries removal and cavity preparation. Twenty freshly extracted human teeth with carious lesions were used in the study. They were assigned to four groups depending on the method used for preparation: Group 1--Cavity preparation using Er: YAG laser (LiteTouch, Syneron, Israel). Group 2--Chemomechanical preparation using colourless Carisolv gel (MediTeam AB, Savedalen, Sweden). Group 3--Mechanical rotary preparation using diamond burs and air turbine. Group 4--Mechanical rotary preparation using by steel burs and micromotor. The preparations were performed strictly according to the manufacturer's instructions for proper use of instruments. The teeth samples were prepared for histological study and investigated by a scanning electron microscope at different magnification; the morphological changes in the tissues were registered and compared. There were considerable differences in the surface characteristics of the dental tissues when we analysed the photomicrographs of the specimens obtained using scanning electron microscopy (SEM). The surface after laser treatment remained highly retentive with no residual smear layer; the second best results in this respect were registered when teeth were chemomechanically excavated with Carisolv gel. The mechanical methods of cavity preparation resulted in surfaces with a smear layer of dentin without any microretentions. The scanning electron microscopy of hard dental tissues prepared using steel and diamond burs showed surfaces covered with a thick smear layer that may be relevant to the subsequent bonding of adhesive restorative materials to the prepared cavity. In preparing the surface using a turbine with diamond burs the smear layer was thinner and part of the dentinal tubules orifices were open in the area of water turbulence. SEM analysis of hard

  18. A Miniature Swine Model for Stem Cell-Based De Novo Regeneration of Dental Pulp and Dentin-Like Tissue.

    Science.gov (United States)

    Zhu, Xiaofei; Liu, Jie; Yu, Zongdong; Chen, Chao-An; Aksel, Hacer; Azim, Adham A; Huang, George T-J

    2018-01-03

    The goal of this study was to establish mini-swine as a large animal model for stem cell-based pulp regeneration studies. Swine dental pulp stem cells (sDPSCs) were isolated from mini-swine and characterized in vitro. For in vivo studies, we first employed both ectopic and semi-orthotopic study models using severe combined immunodeficiency mice. One is hydroxyapatite-tricalcium phosphate (HA/TCP) model for pulp-dentin complex formation, and the other is tooth fragment model for complete pulp regeneration with new dentin depositing along the canal walls. We found that sDPSCs are similar to their human counterparts exhibiting mesenchymal stem cell characteristics with ability to form colony forming unit-fibroblastic and odontogenic differentiation potential. sDPSCs formed pulp-dentin complex in the HA/TCP model and showed pulp regeneration capacity in the tooth fragment model. We then tested orthotopic pulp regeneration on mini-swine including the use of multi-rooted teeth. Using autologous sDPSCs carried by hydrogel and transplanted into the mini-swine root canal space, we observed regeneration of vascularized pulp-like tissue with a layer of newly deposited dentin-like (rD) tissue or osteodentin along the canal walls. In some cases, dentin bridge-like structure was observed. Immunohistochemical analysis detected the expression of nestin, dentin sialophosphoprotein, dentin matrix protein 1, and bone sialoprotein in odontoblast-like cells lining against the produced rD. We also tested the use of allogeneic sDPSCs for the same procedures. Similar findings were observed in allogeneic transplantation. This study is the first to show an establishment of mini-swine as a suitable large animal model utilizing multi-rooted teeth for further cell-based pulp regeneration studies.

  19. A Novel Strategy to Engineer Pre-Vascularized Full-Length Dental Pulp-like Tissue Constructs.

    Science.gov (United States)

    Athirasala, Avathamsa; Lins, Fernanda; Tahayeri, Anthony; Hinds, Monica; Smith, Anthony J; Sedgley, Christine; Ferracane, Jack; Bertassoni, Luiz E

    2017-06-12

    The requirement for immediate vascularization of engineered dental pulp poses a major hurdle towards successful implementation of pulp regeneration as an effective therapeutic strategy for root canal therapy, especially in adult teeth. Here, we demonstrate a novel strategy to engineer pre-vascularized, cell-laden hydrogel pulp-like tissue constructs in full-length root canals for dental pulp regeneration. We utilized gelatin methacryloyl (GelMA) hydrogels with tunable physical and mechanical properties to determine the microenvironmental conditions (microstructure, degradation, swelling and elastic modulus) that enhanced viability, spreading and proliferation of encapsulated odontoblast-like cells (OD21), and the formation of endothelial monolayers by endothelial colony forming cells (ECFCs). GelMA hydrogels with higher polymer concentration (15% w/v) and stiffness enhanced OD21 cell viability, spreading and proliferation, as well as endothelial cell spreading and monolayer formation. We then fabricated pre-vascularized, full-length, dental pulp-like tissue constructs by dispensing OD21 cell-laden GelMA hydrogel prepolymer in root canals of extracted teeth and fabricating 500 µm channels throughout the root canals. ECFCs seeded into the microchannels successfully formed monolayers and underwent angiogenic sprouting within 7 days in culture. In summary, the proposed approach is a simple and effective strategy for engineering of pre-vascularized dental pulp constructs offering potentially beneficial translational outcomes.

  20. Effects of SOX2 on Proliferation, Migration and Adhesion of Human Dental Pulp Stem Cells.

    Directory of Open Access Journals (Sweden)

    Pengfei Liu

    Full Text Available As a key factor for cell pluripotent and self-renewing phenotypes, SOX2 has attracted scientists' attention gradually in recent years. However, its exact effects in dental pulp stem cells (DPSCs are still unclear. In this study, we mainly investigated whether SOX2 could affect some biological functions of DPSCs. DPSCs were isolated from the dental pulp of human impacted third molar. SOX2 overexpressing DPSCs (DPSCs-SOX2 were established through retroviral infection. The effect of SOX2 on cell proliferation, migration and adhesion ability was evaluated with CCK-8, trans-well system and fibronectin-induced cell attachment experiment respectively. Whole genome expression of DPSCs-SOX2 was analyzed with RNA microarray. Furthermore, a rescue experiment was performed with SOX2-siRNA in DPSC-SOX2 to confirm the effect of SOX2 overexpression in DPSCs. We found that SOX2 overexpression could result in the enhancement of cell proliferation, migration, and adhesion in DPSCs obviously. RNA microarray analysis indicated that some key genes in the signal pathways associated with cell cycle, migration and adhesion were upregulated in different degree, and the results were further confirmed with qPCR and western-blot. Finally, DPSC-SOX2 transfected with SOX2-siRNA showed a decrease of cell proliferation, migration and adhesion ability, which further confirmed the biological effect of SOX2 in human DPSCs. This study indicated that SOX2 could improve the cell proliferation, migration and adhesion ability of DPSCs through regulating gene expression about cell cycle, migration and adhesion, and provided a novel strategy to develop seed cells with strong proliferation, migration and adhesion ability for tissue engineering.

  1. Rapid ablation of dental hard tissue using promoter-assisted pulsed Nd:YAG laser

    Science.gov (United States)

    Frederickson, Christopher J.; Lu, Quiang; Hayes, Donald J.; Wallace, David B.; Grove, Michael E.; Bell, Brent A.; Motamedi, Massoud; Rastegar, Sohi; Wright, C. G.; Arcoria, Charles J.

    1997-05-01

    Nd:YAG lasers have been used previously for selective removal of various material from teeth. To permit ablation of healthy enamel with the Nd:YAG laser, we have adopted a strategy in which micro-drops of photoabsorptive 'promoters' are placed on the enamel to enhance absorption of individual laser pulses. Ink-jet technology dispenses the micro-drops with micron- and millisecond-scale precision. Various promoters using drug and cosmetic dyes, indocyanine green, or carbon-black pigments have been studied. Typical ablation parameters are 1.064 micrometers ; 20-180 mJ per pulse; 100 microsecond(s) ; 10-30 pulses/sec; 0.2-2.0 nl drops. Recent results from the program include: (1) For a variety of promoters, a monotonic relationship obtains between absorption coefficient at 1.064 micrometers and the efficiency of ablation of enamel. (2) With different promoter volumes, the efficiency of ablation rises, plateaus, then falls with increasing volume. (3) At drilling rates of 30 pulses/sec, ablation efficiency approaches rates of 0.1 mm3/sec. LM and SEM observations show a glassy 'pebbled' crater surface indicative of hydroxyapatite that has cooled, condensed, and solidified on the crater walls. Together these results favor the view that a micro-drop promoter-assisted Nd:YAG drill can five clinically useful ablations hard dental tissue.

  2. Determinants of human adipose tissue gene expression

    DEFF Research Database (Denmark)

    Viguerie, Nathalie; Montastier, Emilie; Maoret, Jean-José

    2012-01-01

    Weight control diets favorably affect parameters of the metabolic syndrome and delay the onset of diabetic complications. The adaptations occurring in adipose tissue (AT) are likely to have a profound impact on the whole body response as AT is a key target of dietary intervention. Identification ...

  3. Absence of lymphatic vessels in human dental pulp: a morphological study.

    Science.gov (United States)

    Gerli, Renato; Secciani, Ilaria; Sozio, Francesca; Rossi, Antonella; Weber, Elisabetta; Lorenzini, Guido

    2010-04-01

    Few and controversial data are available in the literature regarding the presence of lymphatic vessels in the human dental pulp. The present study was designed to examine morphologically the existence of a lymph drainage system in human dental pulp. Human dental pulp and skin sections were immunohistochemically stained with specific antibodies for lymphatic endothelium (D2-40, LYVE-1, VEGFR-3 [vascular endothelial growth factor receptor-3], and Prox-1), with the pan-endothelial markers CD31 and von Willebrand factor (vWF), and with the blood-specific marker CD34. Several blood vessels were identified in human pulps and skin. Lymphatic vessels were found in all human skin samples but in none of the pulps examined. Western blotting performed on human dermis and on pulps treated with collagenase (to remove odontoblasts) confirmed these results. Transmission electron microscopy indicated that vessels which, by light microscopy, appeared to be initial lymphatic vessels had no anchoring filaments or discontinuous basement membrane, both of which are typical ultrastructural characteristics of lymphatic vessels. These results suggest that under normal conditions human dental pulp does not contain true lymphatic vessels. The various theories about dental pulp interstitial fluid circulation should be revised accordingly.

  4. [Three dimensional bioprinting technology of human dental pulp cells mixtures].

    Science.gov (United States)

    Xue, Shi-hua; Lv, Pei-jun; Wang, Yong; Zhao, Yu; Zhang, Ting

    2013-02-18

    To explore the three dimensional(3D)bioprinting technology, using human dental pulp cells (hDPCs) mixture as bioink and to lay initial foundations for the application of the 3D bioprinting technology in tooth regeneration. Imageware 11.0 computer software was used to aid the design of the 3D biological printing blueprint. Sodium alginate-gelatin hydrosol was prepared and mixed with in vitro isolated hDPCs. The mixture contained 20 g/L sodium alginate and 80 g/L gelatin with cell density of 1×10(6)/mL. The bioprinting of hDPCs mixture was carried out according to certain parameters; the 3D constructs obtained by printing were examined; the viability of hDPCs after printing by staining the constructs with calcein-AM and propidium iodide dye and scanning of laser scanning confocal microscope was evaluated. The in vitro constructs obtained by the bioprinting were cultured, and the proliferation of hDPCs in the constructs detected. By using Imageware 11.0 software, the 3D constructs with the grid structure composed of the accumulation of staggered cylindrical microfilament layers were obtained. According to certain parameters, the hDPCs-sodium alginate-gelatin blends were printed by the 3D bioprinting technology. The self-defined shape and dimension of 3D constructs with the cell survival rate of 87%± 2% were constructed. The hDPCs could proliferate in 3D constructs after printing. In this study, the 3D bioprinting of hDPCs mixtures was realized, thus laying initial foundations for the application of the 3D bioprinting technology in tooth regeneration.

  5. Human dental pulp stem cells and gingival fibroblasts seeded into silk fibroin scaffolds have the same ability in attracting vessels

    Directory of Open Access Journals (Sweden)

    Anna eWoloszyk

    2016-04-01

    Full Text Available Neovascularization is one of the most important processes during tissue repair and regeneration. Current healing approaches based on the use of biomaterials combined with stem cells in critical-size bone defects fail due to the insufficient implant vascularization and integration into the host tissues. Therefore, here we studied the attraction, ingrowth, and distribution of blood vessels from the chicken embryo chorioallantoic membrane into implanted silk fibroin scaffolds seeded with either human dental pulp stem cells or human gingival fibroblasts. Perfusion capacity was evaluated by non-invasive in vivo Magnetic Resonance Imaging while the number and density of blood vessels were measured by histomorphometry. Our results demonstrate that human dental pulp stem cells and gingival fibroblasts possess equal abilities in attracting vessels within silk fibroin scaffolds. Additionally, the prolonged in vitro pre-incubation period of these two cell populations favors the homogeneous distribution of vessels within silk fibroin scaffolds, which further improves implant survival and guarantees successful healing and regeneration.

  6. Effects of gamma radiation on hard dental tissues of albino rats using scanning electron microscope - Part 1

    Science.gov (United States)

    El-Faramawy, Nabil; Ameen, Reham; El-Haddad, Khaled; Maghraby, Ahmed; El-Zainy, Medhat

    2011-12-01

    In the present study, 40 adult male albino rats were used to study the effect of gamma radiation on the hard dental tissues (enamel surface, dentinal tubules and the cementum surface). The rats were irradiated at 0.2, 0.5, 1.0, 2.0, 4.0 and 6.0 Gy gamma doses. The effects of irradiated hard dental tissues samples were investigated using a scanning electron microscope. For doses up to 0.5 Gy, there was no evidence of the existence of cracks on the enamel surface. With 1 Gy irradiation dose, cracks were clearly observed with localized erosive areas. At 2 Gy irradiation dose, the enamel showed morphological alterations as disturbed prismatic and interprismatic areas. An increase in dentinal tubules diameter and a contemporary inter-tubular dentine volume decrease were observed with higher irradiation dose. Concerning cementum, low doses,teeth.

  7. French legal framework relating to human tissues and cells.

    Science.gov (United States)

    Pascal, P; Damour, O; Colpart, J J; Braye, F

    2000-03-01

    Thousands of patients receive human tissue grafts every year. Developments in cell and tissue engineering have also increased considerably the number of available products of human origin. France has very strict regulations, in part stimulated by problems of public health and ethics that have emerged in recent years and also in part as a result of a report by the 'Inspection Générale des Affaires Sociales' on the removal and grafting of human tissues in May 1993. These have resulted in two laws on bio-ethics being passed, in July 1994, that are the basis of current legislation and represent the first steps in differentiating between organs and tissues or cells. Henceforth, the French legal framework covering tissues and cells of human origin has been increased to include a large number of legislative texts and regulations. The fundamental ethical principles that are consent, free donation, anonymity, no publicity and respect for public health have become a major ethical imperative that applies to all products originating from the human body including tissue and cells. In addition, specific provisions have been made covering: removal (conditions for removal and system for authorization); conservation, transformation, distribution, packaging, import and export of tissues and cells; and tissue and cell grafts. Finally, penal and administrative sanctions have been foreseen where there is non-compliance with these regulations.

  8. Distribution of a major connective tissue protein, fibronectin, in normal human tissues.

    Science.gov (United States)

    Stenman, S; Vaheri, A

    1978-04-01

    Fibronectin is a major surface-associated glycoprotein of cultured fibroblasts and it is also present in human plasma. Antiserum specific for human fibronectin was used to study the distribution of fibronectin in normal adult human tissues. The protein was detected (a) characteristically in various basement membranes including capillary walls: (b) around individual smooth muscle cells and in the sarcolemma of striated muscle fibers; and (c) in the stroma of lymphatic tissue and as thin fibers in loose connective tissue. The distribution of fibronectin was distinct from that of collagen and elastic fibers, but was very similar to reticulin, as demonstrated by conventional histological staining. The results indicate that fibronectin is a major component of connective tissue matrix. The distribution also indicates that most types of adherent cells abut fibronectin-containing structures. This supports the possible role of fibronectin in cell-cell and cell-matrix interactions in tissues.

  9. A High-Resolution Proteomic Landscaping of Primary Human Dental Stem Cells: Identification of SHED- and PDLSC-Specific Biomarkers.

    Science.gov (United States)

    Taraslia, Vasiliki; Lymperi, Stefania; Pantazopoulou, Vasiliki; Anagnostopoulos, Athanasios K; Papassideri, Issidora S; Basdra, Efthimia K; Bei, Marianna; Kontakiotis, Evangelos G; Tsangaris, George Th; Stravopodis, Dimitrios J; Anastasiadou, Ema

    2018-01-05

    Dental stem cells (DSCs) have emerged as a promising tool for basic research and clinical practice. A variety of adult stem cell (ASC) populations can be isolated from different areas within the dental tissue, which, due to their cellular and molecular characteristics, could give rise to different outcomes when used in potential applications. In this study, we performed a high-throughput molecular comparison of two primary human adult dental stem cell (hADSC) sub-populations: Stem Cells from Human Exfoliated Deciduous Teeth (SHEDs) and Periodontal Ligament Stem Cells (PDLSCs). A detailed proteomic mapping of SHEDs and PDLSCs, via employment of nano-LC tandem-mass spectrometry (MS/MS) revealed 2032 identified proteins in SHEDs and 3235 in PDLSCs. In total, 1516 proteins were expressed in both populations, while 517 were unique for SHEDs and 1721 were exclusively expressed in PDLSCs. Further analysis of the recorded proteins suggested that SHEDs predominantly expressed molecules that are involved in organizing the cytoskeletal network, cellular migration and adhesion, whereas PDLSCs are highly energy-producing cells, vastly expressing proteins that are implicated in various aspects of cell metabolism and proliferation. Applying the Rho-GDI signaling pathway as a paradigm, we propose potential biomarkers for SHEDs and for PDLSCs, reflecting their unique features, properties and engaged molecular pathways.

  10. A High-Resolution Proteomic Landscaping of Primary Human Dental Stem Cells: Identification of SHED- and PDLSC-Specific Biomarkers

    Directory of Open Access Journals (Sweden)

    Vasiliki Taraslia

    2018-01-01

    Full Text Available Dental stem cells (DSCs have emerged as a promising tool for basic research and clinical practice. A variety of adult stem cell (ASC populations can be isolated from different areas within the dental tissue, which, due to their cellular and molecular characteristics, could give rise to different outcomes when used in potential applications. In this study, we performed a high-throughput molecular comparison of two primary human adult dental stem cell (hADSC sub-populations: Stem Cells from Human Exfoliated Deciduous Teeth (SHEDs and Periodontal Ligament Stem Cells (PDLSCs. A detailed proteomic mapping of SHEDs and PDLSCs, via employment of nano-LC tandem-mass spectrometry (MS/MS revealed 2032 identified proteins in SHEDs and 3235 in PDLSCs. In total, 1516 proteins were expressed in both populations, while 517 were unique for SHEDs and 1721 were exclusively expressed in PDLSCs. Further analysis of the recorded proteins suggested that SHEDs predominantly expressed molecules that are involved in organizing the cytoskeletal network, cellular migration and adhesion, whereas PDLSCs are highly energy-producing cells, vastly expressing proteins that are implicated in various aspects of cell metabolism and proliferation. Applying the Rho-GDI signaling pathway as a paradigm, we propose potential biomarkers for SHEDs and for PDLSCs, reflecting their unique features, properties and engaged molecular pathways.

  11. Construction of retroviral recombinant containing human tissue ...

    African Journals Online (AJOL)

    Correct orientation was verified by restriction endonuclease digestion. Human full length TIMP-2 gene was ligated into a plasmid, which was then transfected into PA317 cell line. G418-resistant individual clones were selected to transfect human SGC-7901 cell line. Cell proliferation, cell electrophoresis, soft agar colony ...

  12. The effects of platelet-rich plasma derived from human umbilical cord blood on the osteogenic differentiation of human dental stem cells.

    Science.gov (United States)

    Lee, Jung-Yeon; Nam, Hyun; Park, Yoon-Jeong; Lee, Seung-Jin; Chung, Chong-Pyoung; Han, Soo-Boo; Lee, Gene

    2011-02-01

    Platelet-rich plasma (PRP) is an emerging therapeutic application because PRP contains various growth factors that have beneficial effects on tissue regeneration and engineering. Mesenchymal stem cells and PRP derived from peripheral blood have been well studied. In this study, we investigated the effects of PRP derived from human umbilical cord blood (UCB-PRP) on proliferation, alkaline phosphatase (ALP) activity, and osteogenic differentiation of stem cells from human exfoliated deciduous teeth (SHEDs), dental pulp stem cells (DPSCs), and periodontal ligament stem cells (PDLSCs). Three types of dental stem cells were primarily isolated and characterized by flow cytometric analysis. Dental stem cells were exposed to various concentrations of UCB-PRP, which resulted in the proliferation of dental stem cells. Treatment with 2% UCB-PRP resulted in the highest level of proliferation. The ALP activity of DPSCs and PDLSCs increased following treatment with UCB-PRP in a dose-dependent manner up to a concentration of 2%. ALP activity decreased with higher concentration of UCB-PRP. The effects of UCB-PRP on calcium deposition were similar to those on proliferation and ALP activity. Treatment with 2% UCB-PRP resulted in the highest calcium depositions in DPSCs and PDLSCs; however, treatment with 1% UCB-PRP resulted in the highest calcium deposition in SHEDs. The concentrations of platelet-derived growth factor-AB and transforming growth factor-β1 in UCB-PRP were investigated and found to be comparable to the amounts in peripheral blood. Overall, UCB-PRP had beneficial effects on the proliferation and osteogenic differentiation of dental stem cells. Determination of the optimal concentration of UCB-PRP requires further investigation for clinical applications.

  13. Explant culture: An advantageous method for isolation of mesenchymal stem cells from human tissues.

    Science.gov (United States)

    Hendijani, Fatemeh

    2017-04-01

    Mesenchymal stem cell (MSC) research progressively moves towards clinical phases. Accordingly, a wide range of different procedures were presented in the literature for MSC isolation from human tissues; however, there is not yet any close focus on the details to offer precise information for best method selection. Choosing a proper isolation method is a critical step in obtaining cells with optimal quality and yield in companion with clinical and economical considerations. In this concern, current review widely discusses advantages of omitting proteolysis step in isolation process and presence of tissue pieces in primary culture of MSCs, including removal of lytic stress on cells, reduction of in vivo to in vitro transition stress for migrated/isolated cells, reduction of price, processing time and labour, removal of viral contamination risk, and addition of supporting functions of extracellular matrix and released growth factors from tissue explant. In next sections, it provides an overall report of technical highlights and molecular events of explant culture method for isolation of MSCs from human tissues including adipose tissue, bone marrow, dental pulp, hair follicle, cornea, umbilical cord and placenta. Focusing on informative collection of molecular and methodological data about explant methods can make it easy for researchers to choose an optimal method for their experiments/clinical studies and also stimulate them to investigate and optimize more efficient procedures according to clinical and economical benefits. © 2017 John Wiley & Sons Ltd.

  14. Natural Rubber Nanocomposite with Human-Tissue-Like Mechanical Characteristic

    Science.gov (United States)

    Murniati, Riri; Novita, Nanda; Sutisna; Wibowo, Edy; Iskandar, Ferry; Abdullah, Mikrajuddin

    2017-07-01

    The blends of synthetic rubber and natural rubber with nanosilica were prepared using a blending technique in presence of different filler volume fraction. The effect of filler on morphological and mechanical characteristics was studied. Utilization of human cadaver in means of medical study has been commonly used primarily as tools of medical teaching and training such as surgery. Nonetheless, human cadaver brought inevitable problems. So it is necessary to find a substitute material that can be used to replace cadavers. In orthopaedics, the materials that resemble in mechanical properties to biological tissues are elastomers such as natural rubber (latex) and synthetic rubber (polyurethanes, silicones). This substitution material needs to consider the potential of Indonesia to help the development of the nation. Indonesia is the second largest country producer of natural rubber in the world. This paper aims to contribute to adjusting the mechanical properties of tissue-mimicking materials (TMMs) to the recommended range of biological tissue value and thus allow the development of phantoms with greater stability and similarity to human tissues. Repeatability for the phantom fabrication process was also explored. Characteristics were then compared to the control and mechanical characteristics of different human body part tissue. Nanosilica is the best filler to produce the best nanocomposite similarities with human tissue. We produced composites that approaching the properties of human internal tissues.

  15. Study of dental occlusion in ancient human remains: a methodological approach.

    Science.gov (United States)

    Fiorin, Elena; Cadafalch, Joan; Ceperuelo, Dolors; Adserias Adserias, Maria José; Chimenos-Küstner, Eduard; Malgosa, Assumpció

    2014-09-01

    The anthropological dental and maxillary study in human skeletal remains usually refers to alterations or conditions of the oral cavity. These alterations could have repercussions on life style, dietary habits and diseases. In this particular context, dental occlusion is not often analyzed due to the fragmented condition of the remains, and especially due to the lack of methodology adapted to study ancient remains. The aim of this study is to propose an anthropological method based on clinical dental practice. In the method presented in this work, odontological parameters such as overjet, overbite, and Angle's Classification of Malocclusion, are evaluated.

  16. [Metabolism of ornithine in human gingival tissue].

    Science.gov (United States)

    Pinna, G G; Chessa, G; Luglié, P F; Trova, R; Sisini, A

    1989-11-01

    The behavior of two enzymes of the ornithine pathway, leading to the formation of proline and, eventually, of collagen, arginase and ornithine oxo-acid aminotransferase has been investigated in normal and inflamed gingival tissue. Both enzymatic activities show a statistically significant decrease in pathological samples as compared to normal ones. The data on arginase activity may be in agreement with the already documented low level of urea in pathological gingival fluid, while a decrease of the ornithine aminotransferase activity could be linked to the phenomenon of gingival retraction, i.e. the lack of complete regeneration of gingival tissue usually observed in chronically inflamed subjects, that would be reasonably parallel to a decreased proline/collagen synthesis.

  17. Three-Dimensionally Engineered Normal Human Broncho-epithelial Tissue-Like Assemblies: Target Tissues for Human Respiratory Viral Infections

    Science.gov (United States)

    Goodwin, T. J.; McCarthy, M.; Lin, Y-H

    2006-01-01

    In vitro three-dimensional (3D) human broncho-epithelial (HBE) tissue-like assemblies (3D HBE TLAs) from this point forward referred to as TLAs were engineered in Rotating Wall Vessel (RWV) technology to mimic the characteristics of in vivo tissues thus providing a tool to study human respiratory viruses and host cell interactions. The TLAs were bioengineered onto collagen-coated cyclodextran microcarriers using primary human mesenchymal bronchial-tracheal cells (HBTC) as the foundation matrix and an adult human bronchial epithelial immortalized cell line (BEAS-2B) as the overlying component. The resulting TLAs share significant characteristics with in vivo human respiratory epithelium including polarization, tight junctions, desmosomes, and microvilli. The presence of tissue-like differentiation markers including villin, keratins, and specific lung epithelium markers, as well as the production of tissue mucin, further confirm these TLAs differentiated into tissues functionally similar to in vivo tissues. Increasing virus titers for human respiratory syncytial virus (wtRSVA2) and parainfluenza virus type 3 (wtPIV3 JS) and the detection of membrane bound glycoproteins over time confirm productive infections with both viruses. Therefore, TLAs mimic aspects of the human respiratory epithelium and provide a unique capability to study the interactions of respiratory viruses and their primary target tissue independent of the host's immune system.

  18. Three-Dimensionally Engineered Normal Human Lung Tissue-Like Assemblies: Target Tissues for Human Respiratory Viral Infections

    Science.gov (United States)

    Goodwin, Thomas J.; McCarthy, M.; Lin, Y-H.; Deatly, A. M.

    2008-01-01

    In vitro three-dimensional (3D) human lung epithelio-mesenchymal tissue-like assemblies (3D hLEM TLAs) from this point forward referred to as TLAs were engineered in Rotating Wall Vessel (RWV) technology to mimic the characteristics of in vivo tissues thus providing a tool to study human respiratory viruses and host cell interactions. The TLAs were bioengineered onto collagen-coated cyclodextran microcarriers using primary human mesenchymal bronchial-tracheal cells (HBTC) as the foundation matrix and an adult human bronchial epithelial immortalized cell line (BEAS-2B) as the overlying component. The resulting TLAs share significant characteristics with in vivo human respiratory epithelium including polarization, tight junctions, desmosomes, and microvilli. The presence of tissue-like differentiation markers including villin, keratins, and specific lung epithelium markers, as well as the production of tissue mucin, further confirm these TLAs differentiated into tissues functionally similar to in vivo tissues. Increasing virus titers for human respiratory syncytial virus (wtRSVA2) and the detection of membrane bound glycoproteins over time confirm productive infection with the virus. Therefore, we assert TLAs mimic aspects of the human respiratory epithelium and provide a unique capability to study the interactions of respiratory viruses and their primary target tissue independent of the host s immune system.

  19. Genome-wide transcriptomic alterations induced by ethanol treatment in human dental pulp stem cells (DPSCs)

    OpenAIRE

    Omar Khalid; Kim, Jeffrey J.; Lewei Duan; Michael Hoang; David Elashoff; Yong Kim

    2014-01-01

    Human dental pulp stem cells (DPSCs) isolated from adult dental pulp are multipotent mesenchymal stem cells that can be directed to differentiate into osteogenic/odontogenic cells and also trans-differentiate into neuronal cells. The utility of DPSC has been explored in odontogenic differentiation for tooth regeneration. Alcohol abuse appears to lead to periodontal disease, tooth decay and mouth sores that are potentially precancerous. Persons who abuse alcohol are at high risk of having seri...

  20. The prevalence, pattern and clinical presentation of developmental dental hard-tissue anomalies in children with primary and mix dentition from Ile-Ife, Nigeria

    National Research Council Canada - National Science Library

    Temilola, Dada Oluwaseyi; Folayan, Morenike Oluwatoyin; Fatusi, Olawunmi; Chukwumah, Nneka Maureen; Onyejaka, Nneka; Oziegbe, Elizabeth; Oyedele, Titus; Kolawole, Kikelomo Adebanke; Agbaje, Hakeem

    2014-01-01

    .... The objective of this study is to determine the prevalence and pattern of presentation of dental hard-tissue developmental anomalies in the mix dentition of children residing in Ile-Ife, a suburban region of Nigeria...

  1. Clinicopathological evaluation of 164 dental follicles and dentigerous cysts with emphasis on the presence of odontogenic epithelium in the connective tissue. The hypothesis of "focal ameloblastoma"

    NARCIS (Netherlands)

    Meleti, M.; van der Waal, I.

    2013-01-01

    Objectives: Some ameloblastomas presumably originate from odontogenic epithelium within the connective tissue of dental follicles and dentigerous cysts. Therefore, it would seem reasonable to discuss as whether odontogenic epithelium proliferations, frankly displaying ameloblastomatous features

  2. Awareness and Knowledge of Undergraduate Dental Students about Sterilization/Disinfection Methods of Extracted Human Teeth.

    Science.gov (United States)

    Deogade, S C; Mantri, S S; Saxena, S; Sumathi, K

    2016-01-01

    Dental undergraduate students work on extracted human teeth in preclinical practical's to learn technical skills before entering the clinics and delivering dental care to the patients. The aim of the present investigation was to assess the awareness and knowledge toward sterilization/disinfection methods of extracted human teeth in a selected group of Indian dental students. In this descriptive cross-sectional study, the participants consisted of 2 nd -, 3 rd -, 4 th -, and 5 th -year dental students. Data were collected by questionnaires and analyzed by Mann-Whitney U-test and Kruskal-Wallis test using SPSS software version 16 for Windows (SPSS Inc., Chicago, IL, USA). In this study, 235 dental students participated in the study. The average awareness and knowledge score was 7.27 (1.92). Based on the opinion of 57% (134/235) students, hydrogen peroxide was selected as the suitable material for sterilization and 24.6% (58/235) students believed that autoclave sterilization is a good way for the purpose. The results of this investigation indicated that awareness and knowledge of undergraduate dental students in relation to sterilization/disinfection methods of extracted human teeth were good. However, deficiencies were observed in relation to teaching the material and methods suitable for sterilization.

  3. Microwave non-contact imaging of subcutaneous human body tissues

    Science.gov (United States)

    Chernokalov, Alexander; Khripkov, Alexander; Cho, Jaegeol; Druchinin, Sergey

    2015-01-01

    A small-size microwave sensor is developed for non-contact imaging of a human body structure in 2D, enabling fitness and health monitoring using mobile devices. A method for human body tissue structure imaging is developed and experimentally validated. Subcutaneous fat tissue reconstruction depth of up to 70 mm and maximum fat thickness measurement error below 2 mm are demonstrated by measurements with a human body phantom and human subjects. Electrically small antennas are developed for integration of the microwave sensor into a mobile device. Usability of the developed microwave sensor for fitness applications, healthcare, and body weight management is demonstrated. PMID:26609415

  4. Microwave non-contact imaging of subcutaneous human body tissues.

    Science.gov (United States)

    Kletsov, Andrey; Chernokalov, Alexander; Khripkov, Alexander; Cho, Jaegeol; Druchinin, Sergey

    2015-10-01

    A small-size microwave sensor is developed for non-contact imaging of a human body structure in 2D, enabling fitness and health monitoring using mobile devices. A method for human body tissue structure imaging is developed and experimentally validated. Subcutaneous fat tissue reconstruction depth of up to 70 mm and maximum fat thickness measurement error below 2 mm are demonstrated by measurements with a human body phantom and human subjects. Electrically small antennas are developed for integration of the microwave sensor into a mobile device. Usability of the developed microwave sensor for fitness applications, healthcare, and body weight management is demonstrated.

  5. Modern views on the pathogenesis of hard dental tissues and periodontium lesions and means of their treatment in children with chronic diseases of the gastrointestinal tract

    OpenAIRE

    Krupey V.Y.

    2014-01-01

    Changes in the mouth covity often reflect regularities of pathogenesis of a number of disease states, and primarily from the digestive tract. Therefore, the purpose of the study was to clarify pathogenesis of certain lesions of hard dental tissues and periodontal tissues in children with chronic diseases of the gastrointestinal tract and development of schemes for their treatment. The study observed 441 children aged from 7 to 15 years with dental caries and generalized chronic catarrhal ging...

  6. The Role of Nephronectin on Proliferation and Differentiation in Human Dental Pulp Stem Cells

    Directory of Open Access Journals (Sweden)

    Jia Tang

    2017-01-01

    Full Text Available Aim. The purpose of the current study was to investigate the effects of nephronectin (Npnt in human dental pulp stem cells (hDPSCs. Methodology. Npnt was coated to nontissue culture-treated polystyrene (non-PS plates. The presence of immobilized protein on the surface was detected by polyclonal rabbit primary anti-Npnt antibody. Then the cell number was counted and compared with PBS-, bovine serum albumin- (BSA-, fish scale type I collagen- (FCOL1-, and human fibronectin- (Fn- coated wells. Cell proliferation was assessed using CCK-8 assay. Cell morphology was observed under light microscopy and fluorescence microscopy. Lastly, the mRNA expression profiles of integrins, dentin sialophosphoprotein (DSPP, bone sialoprotein (BSP, and mineralization capacity of hDPSCs were investigated by real time RT-PCR and alizarin red staining, respectively. Results. Npnt mediates hDPSC adhesion and spreading partially via the Arg-Gly-Asp (RGD motif. Npnt enhanced the mRNA expression of ITGA1, ITGA4, ITGA7, and ITGB1 on day five. Npnt downregulated DSPP but significantly upregulated BSP mRNA expression at day 28. Further, Npnt and FCOL1 accelerated the matrix mineralization in hDPSCs. Conclusions. The current findings implicate that Npnt would be favorable to recruit hDPSCs and conducive to mineralization in hDPSCs. The combination of Npnt with hDPSCs may offer a promising approach for hard tissue regeneration.

  7. Inflammatory response of human dental pulp to at-home and in-office tooth bleaching.

    Science.gov (United States)

    Vaz, Maysa Magalhães; Lopes, Lawrence Gonzaga; Cardoso, Paula Carvalho; Souza, João Batista de; Batista, Aline Carvalho; Costa, Nádia Lago; Torres, Érica Miranda; Estrela, Carlos

    2016-01-01

    This study evaluated the inflammatory responses of human dental pulp after the use of two bleaching techniques. Pulp samples were collected from human third molars extracted for orthodontic reasons and divided into three groups: control - no tooth bleaching (CG) (n=7); at-home bleaching with 15% carbamide peroxide (AH) (n = 10), and in-office bleaching with 38% hydrogen peroxide (IO) (n=12). Pulps were removed and stained with hematoxylin-eosin for microscopic analysis of inflammation intensity, collagen degradation, and pulp tissue organization. Immunohistochemistry was used to detect mast cells (tryptase+), blood vessels (CD31+), and macrophages (CD68+). Chi-square, Kruskal-Wallis, and Mann Whitney tests were used for statistical analysis. The level of significance was set at p0.05). No mast cells were found in the pulp samples analyzed. In-office bleaching with 38% hydrogen peroxide resulted in more intense inflammation, higher macrophages migration, and greater pulp damage then at-home bleaching with 15% carbamide peroxide, however, these bleaching techniques did not induce migration of mast cells and increased the number of blood vessels.

  8. Investigation of functional activity human dental pulp stem cells at acute and chronic pulpitis.

    Science.gov (United States)

    Ustiashvili, M; Kordzaia, D; Mamaladze, M; Jangavadze, M; Sanodze, L

    2014-09-01

    It is already recognized that together with the other connective tissues organ-specific progenic stem cells are also found in postnatal dental pulp. This group of undifferentiated cells is only 1% of total cell population of the pulp. The aim of the study was the identification of stem cells in human dental pulp, detection of their localization and assessment of functional activity during inflammation process and/or at norm. The obtained results showed that at acute pulpitis the pulp stroma is hypocellular in comparison with the norm but cells proliferative activity is low. CD 133 and NCAM (CD 56) positive stem cells were found in perivascularl space of the pulp stroma and in Hohle layer. At process prolongation and transition to the chronic phase pulp stroma is hypercellular, the cells with large, rounded or oval-shaped nuclei with clear chromatin appear together with fibroblasts. They are distributed as about entire thickness of the stroma as especially Hohle layer. In such cells higher proliferative activity (Ki67 expression) was observed. The cells in the mentioned proliferation phase are intensively marked by CD133, the rate of which is high in Hohle layer and along it. A large number of NCAM (CD 56) positive cells appear in pulp stroma. During pulpitis an involvement of stem cells into the process of reparative dentinogenesis should be conducted stepwise. In acute cases of the disease, stem cell perivascularl mobilization and proliferation and its migration to Hohle layer occur in response to irritation /stimulation. Chronification of the process leads not only to the migration of stem cells to the periphery of the pulp but also s their В«maturationВ» (increase of NCAM expression in the stem cells), which causes an increase the number of dentin producing active odontoblasts and initiation of reparative dentinogenesis.

  9. Odontogenic stimulation of human dental pulp cells with bioactive nanocomposite fiber.

    Science.gov (United States)

    Kim, Ga-Hyun; Park, Yong-Duk; Lee, So-Youn; El-Fiqi, Ahmed; Kim, Jung-Ju; Lee, Eun-Jung; Kim, Hae-Won; Kim, Eun-Cheol

    2015-01-01

    The aim of the present study was to investigate the effects of a composite nanofibrous matrix made of biopolymer blend polycaprolactone-gelatin (BP) and mesoporous bioactive glass nanoparticles (BGNs) on the odontogenic differentiation of human dental pulp cells (HDPCs). BGN-BP nanomatrices, with BGN content of up to 20 wt%, were produced via electrospinning. The differentiation of the HDPCs was evaluated by using an ALP activity assay, calcified nodule formation, and mRNA expression for markers. Integrin and its underlying signal pathways were assessed via reverse transcriptase-polymerase chain reaction and Western blot analysis. Although cell growth and attachment on the BGN-BP nanomatrix was similar to that on BP, ALP activity, mineralized nodule formation, and mRNA, expressions involving ALP, osteocalcin, osteopontin, dentin sialophosphoprotein, and dentin matrix protein-1 were greater on BGN-BP. BGN-BP upregulated the key adhesion receptors (integrin components α1, α2, α5, and β1) and activated integrin downstream pathways, such as phosphorylated-focal adhesion kinase (p-FAK), and p-paxillin. In addition, BGN-BP activated BMP receptors, BMP-2 mRNA, and p-Smad 1/5/8, and such activation was blocked by the BMP antagonist, noggin. Furthermore, BGN-BP induced phosphorylation of extracellular signal-regulated kinase, protein kinase 38, and c-Jun-N-terminal kinase mitogen-activated protein kinases and activated expression of the transcription factors Runx2 and Osterix in HDPCs. Collectively, the results indicated for the first time that a BGN-BP composite nanomatrix promoted odontogenic differentiation of HDPCs through the integrin, BMP, and mitogen-activated protein kinases signaling pathway. Moreover, the nanomatrix is considered to be promising scaffolds for the culture of HDPCs and dental tissue engineering. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  10. Overexpression of Receptor for Advanced Glycation End Products and High-Mobility Group Box 1 in Human Dental Pulp Inflammation

    Directory of Open Access Journals (Sweden)

    Salunya Tancharoen

    2014-01-01

    Full Text Available High mobility group box 1 (HMGB1, a nonhistone DNA-binding protein, is released into the extracellular space and promotes inflammation. HMGB1 binds to related cell signaling transduction receptors, including receptor for advanced glycation end products (RAGE, which actively participate in vascular and inflammatory diseases. The aim of this study was to examine whether RAGE and HMGB1 are involved in the pathogenesis of pulpitis and investigate the effect of Prevotella intermedia (P. intermedia lipopolysaccharide (LPS on RAGE and HMGB1 expression in odontoblast-like cells (OLC-1. RAGE and HMGB1 expression levels in clinically inflamed dental pulp were higher than those in healthy dental pulp. Upregulated expression of RAGE was observed in odontoblasts, stromal pulp fibroblasts-like cells, and endothelial-like cell lining human pulpitis tissue. Strong cytoplasmic HMGB1 immunoreactivity was noted in odontoblasts, whereas nuclear HMGB1 immunoreactivity was seen in stromal pulp fibroblasts-like cells in human pulpitis tissue. LPS stimulated OLC-1 cells produced HMGB1 in a dose-dependent manner through RAGE. HMGB1 translocation towards the cytoplasm and secretion from OLC-1 in response to LPS was inhibited by TPCA-1, an inhibitor of NF-κB activation. These findings suggest that RAGE and HMGB1 play an important role in the pulpal immune response to oral bacterial infection.

  11. Overexpression of Receptor for Advanced Glycation End Products and High-Mobility Group Box 1 in Human Dental Pulp Inflammation

    Science.gov (United States)

    Tancharoen, Salunya; Tengrungsun, Tassanee; Suddhasthira, Theeralaksna; Kikuchi, Kiyoshi; Vechvongvan, Nuttavun; Maruyama, Ikuro

    2014-01-01

    High mobility group box 1 (HMGB1), a nonhistone DNA-binding protein, is released into the extracellular space and promotes inflammation. HMGB1 binds to related cell signaling transduction receptors, including receptor for advanced glycation end products (RAGE), which actively participate in vascular and inflammatory diseases. The aim of this study was to examine whether RAGE and HMGB1 are involved in the pathogenesis of pulpitis and investigate the effect of Prevotella intermedia (P. intermedia) lipopolysaccharide (LPS) on RAGE and HMGB1 expression in odontoblast-like cells (OLC-1). RAGE and HMGB1 expression levels in clinically inflamed dental pulp were higher than those in healthy dental pulp. Upregulated expression of RAGE was observed in odontoblasts, stromal pulp fibroblasts-like cells, and endothelial-like cell lining human pulpitis tissue. Strong cytoplasmic HMGB1 immunoreactivity was noted in odontoblasts, whereas nuclear HMGB1 immunoreactivity was seen in stromal pulp fibroblasts-like cells in human pulpitis tissue. LPS stimulated OLC-1 cells produced HMGB1 in a dose-dependent manner through RAGE. HMGB1 translocation towards the cytoplasm and secretion from OLC-1 in response to LPS was inhibited by TPCA-1, an inhibitor of NF-κB activation. These findings suggest that RAGE and HMGB1 play an important role in the pulpal immune response to oral bacterial infection. PMID:25114379

  12. Modulation of human dermal microvascular endothelial cell and human gingival fibroblast behavior by micropatterned silica coating surfaces for zirconia dental implant applications

    Directory of Open Access Journals (Sweden)

    Marta S Laranjeira

    2014-03-01

    Full Text Available Dental ceramic implants have shown superior esthetic behavior and the absence of induced allergic disorders when compared to titanium implants. Zirconia may become a potential candidate to be used as an alternative to titanium dental implants if surface modifications are introduced. In this work, bioactive micropatterned silica coatings were produced on zirconia substrates, using a combined methodology of sol–gel processing and soft lithography. The aim of the work was to compare the in vitro behavior of human gingival fibroblasts (HGFs and human dermal microvascular endothelial cells (HDMECs on three types of silica-coated zirconia surfaces: flat and micropatterned (with pillars and with parallel grooves. Our results showed that cells had a higher metabolic activity (HGF, HDMEC and increased gene expression levels of fibroblast-specific protein-1 (FSP-1 and collagen type I (COL I on surfaces with pillars. Nevertheless, parallel grooved surfaces were able to guide cell growth. Even capillary tube-like networks of HDMEC were oriented according to the surface geometry. Zirconia and silica with different topographies have shown to be blood compatible and silica coating reduced bacteria adhesion. All together, the results indicated that microstructured bioactive coating seems to be an efficient strategy to improve soft tissue integration on zirconia implants, protecting implants from peri-implant inflammation and improving long-term implant stabilization. This new approach of micropatterned silica coating on zirconia substrates can generate promising novel dental implants, with surfaces that provide physical cues to guide cells and enhance their behavior.

  13. Modulation of human dermal microvascular endothelial cell and human gingival fibroblast behavior by micropatterned silica coating surfaces for zirconia dental implant applications

    Science.gov (United States)

    Laranjeira, Marta S.; Carvalho, Ângela; Pelaez-Vargas, Alejandro; Hansford, Derek; Ferraz, Maria Pia; Coimbra, Susana; Costa, Elísio; Santos-Silva, Alice; Fernandes, Maria Helena; Monteiro, Fernando Jorge

    2014-04-01

    Dental ceramic implants have shown superior esthetic behavior and the absence of induced allergic disorders when compared to titanium implants. Zirconia may become a potential candidate to be used as an alternative to titanium dental implants if surface modifications are introduced. In this work, bioactive micropatterned silica coatings were produced on zirconia substrates, using a combined methodology of sol-gel processing and soft lithography. The aim of the work was to compare the in vitro behavior of human gingival fibroblasts (HGFs) and human dermal microvascular endothelial cells (HDMECs) on three types of silica-coated zirconia surfaces: flat and micropatterned (with pillars and with parallel grooves). Our results showed that cells had a higher metabolic activity (HGF, HDMEC) and increased gene expression levels of fibroblast-specific protein-1 (FSP-1) and collagen type I (COL I) on surfaces with pillars. Nevertheless, parallel grooved surfaces were able to guide cell growth. Even capillary tube-like networks of HDMEC were oriented according to the surface geometry. Zirconia and silica with different topographies have shown to be blood compatible and silica coating reduced bacteria adhesion. All together, the results indicated that microstructured bioactive coating seems to be an efficient strategy to improve soft tissue integration on zirconia implants, protecting implants from peri-implant inflammation and improving long-term implant stabilization. This new approach of micropatterned silica coating on zirconia substrates can generate promising novel dental implants, with surfaces that provide physical cues to guide cells and enhance their behavior.

  14. Human tissue models in cancer research: looking beyond the mouse

    Directory of Open Access Journals (Sweden)

    Samuel J. Jackson

    2017-08-01

    Full Text Available Mouse models, including patient-derived xenograft mice, are widely used to address questions in cancer research. However, there are documented flaws in these models that can result in the misrepresentation of human tumour biology and limit the suitability of the model for translational research. A coordinated effort to promote the more widespread development and use of ‘non-animal human tissue’ models could provide a clinically relevant platform for many cancer studies, maximising the opportunities presented by human tissue resources such as biobanks. A number of key factors limit the wide adoption of non-animal human tissue models in cancer research, including deficiencies in the infrastructure and the technical tools required to collect, transport, store and maintain human tissue for lab use. Another obstacle is the long-standing cultural reliance on animal models, which can make researchers resistant to change, often because of concerns about historical data compatibility and losing ground in a competitive environment while new approaches are embedded in lab practice. There are a wide range of initiatives that aim to address these issues by facilitating data sharing and promoting collaborations between organisations and researchers who work with human tissue. The importance of coordinating biobanks and introducing quality standards is gaining momentum. There is an exciting opportunity to transform cancer drug discovery by optimising the use of human tissue and reducing the reliance on potentially less predictive animal models.

  15. Dental OCT

    Science.gov (United States)

    Wilder-Smith, Petra; Otis, Linda; Zhang, Jun; Chen, Zhongping

    This chapter describes the applications of OCT for imaging in vivo dental and oral tissue. The oral cavity is a diverse environment that includes oral mucosa, gingival tissues, teeth and their supporting structures. Because OCT can image both hard and soft tissues of the oral cavity at high resolution, it offers the unique capacity to identity dental disease before destructive changes have progressed. OCT images depict clinically important anatomical features such as the location of soft tissue attachments, morphological changes in gingival tissue, tooth decay, enamel thickness and decay, as well as the structural integrity of dental restorations. OCT imaging allows for earlier intervention than is possible with current diagnostic modalities.

  16. Is hard tissue formation in the dental pulp after the death of the primary odontoblasts a regenerative or a reparative process?

    Science.gov (United States)

    Ricucci, Domenico; Loghin, Simona; Lin, Louis M; Spångberg, Larz S W; Tay, Franklin R

    2014-09-01

    Conceptually, two types of tertiary dentine may be produced in response to caries and environmental irritations: "reactionary dentine" that is secreted by existing primary odontoblasts and "reparative dentine", formed after the death of the odontoblasts by proliferation and differentiation of progenitor cells into odontoblast-like cells. Because histologic evidence for tubular dentine generated by newly differentiated odontoblast-like cells is lacking in human teeth, the present study examined pulpal cellular changes associated with caries/restorations, in the presence or absence of pulpal exposures. Ninety-six extracted human teeth were histologically processed and serial sectioned for light microscopy: 65 contained untreated enamel/dentine caries; 20 were heavily restored and 11 had carious exposures managed by direct pulp-capping. Sparsely distributed, irregularly arranged dentinal tubules were identified from the tertiary dentine formed in teeth with unexposed medium/deep caries and in restored teeth; those tubules were continuous with the tubules of secondary dentine; in some cases, tubules were absent. The palisade odontoblast layer was reduced to a single layer of flattened cells. In direct pulp-capping of pulp exposures, the defects were repaired by the deposition of an amorphous dystrophic calcified tissue that resembled pulp stones more than dentine, sometimes entrapping pulpal remnants. This atubular hard tissue was lined by fibroblasts and collagen fibrils. Histological evidence from the present study indicates that reparative dentinogenesis cannot be considered as a regenerative process since the so-formed hard tissue lacks tubular features characteristic of genuine dentine. Rather, this process represents a repair response that produces calcified scar tissues by pulpal fibroblasts. Formation of hard tissue in the dental pulp after the death of the primary odontoblasts has often been regarded by clinicians as regeneration of dentine. If the objective

  17. Chemical Probes for Visualizing Intact Animal and Human Brain Tissue.

    Science.gov (United States)

    Lai, Hei Ming; Ng, Wai-Lung; Gentleman, Steve M; Wu, Wutian

    2017-06-22

    Newly developed tissue clearing techniques can be used to render intact tissues transparent. When combined with fluorescent labeling technologies and optical sectioning microscopy, this allows visualization of fine structure in three dimensions. Gene-transfection techniques have proved very useful in visualizing cellular structures in animal models, but they are not applicable to human brain tissue. Here, we discuss the characteristics of an ideal chemical fluorescent probe for use in brain and other cleared tissues, and offer a comprehensive overview of currently available chemical probes. We describe their working principles and compare their performance with the goal of simplifying probe selection for neuropathologists and stimulating probe development by chemists. We propose several approaches for the development of innovative chemical labeling methods which, when combined with tissue clearing, have the potential to revolutionize how we study the structure and function of the human brain. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. A family of hyperelastic models for human brain tissue

    Science.gov (United States)

    Mihai, L. Angela; Budday, Silvia; Holzapfel, Gerhard A.; Kuhl, Ellen; Goriely, Alain

    2017-09-01

    Experiments on brain samples under multiaxial loading have shown that human brain tissue is both extremely soft when compared to other biological tissues and characterized by a peculiar elastic response under combined shear and compression/tension: there is a significant increase in shear stress with increasing axial compression compared to a moderate increase with increasing axial tension. Recent studies have revealed that many widely used constitutive models for soft biological tissues fail to capture this characteristic response. Here, guided by experiments of human brain tissue, we develop a family of modeling approaches that capture the elasticity of brain tissue under varying simple shear superposed on varying axial stretch by exploiting key observations about the behavior of the nonlinear shear modulus, which can be obtained directly from the experimental data.

  19. Schwann Cell Phenotype Changes in Aging Human Dental Pulp.

    Science.gov (United States)

    Couve, E; Lovera, M; Suzuki, K; Schmachtenberg, O

    2017-10-01

    Schwann cells are glial cells that support axonal development, maintenance, defense, and regeneration in the peripheral nervous system. There is limited knowledge regarding the organization, plasticity, and aging of Schwann cells within the dental pulp in adult permanent teeth. The present study sought to relate changes in the pattern of Schwann cell phenotypes between young and old adult teeth with neuronal, immune, and vascular components of the dental pulp. Schwann cells are shown to form a prominent glial network at the dentin-pulp interface, consisting of nonmyelinating and myelinating phenotypes, forming a multicellular neuroimmune interface in association with nerve fibers and dendritic cells. Schwann cell phenotypes are recognized by the expression of S100, glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), Sox10, GAP43, and p75NTR markers. In young adult teeth, a dense population of nonmyelinating Schwann cells projects processes in close association with sensory nerve terminals through the odontoblast layer, reaching the adjacent predentin/dentin domain. While GAP43 and p75NTR are highly expressed in nonmyelinating Schwann cells from young adult teeth, the presence of these markers declines significantly in old adult teeth. Myelinated axons, identified by MBP expression, are mainly present at the Raschkow plexus and within nerve bundles in the dental pulp, but their density is significantly reduced in old adult versus young adult teeth. These data reveal age-related changes within the glial network of the dental pulp, in association with a reduction of coronal dental pulp innervation in old adult versus young adult teeth. The prominence of Schwann cells as a cellular component at the dentin-pulp interface supports the notion that their association with sensory nerve terminals and immune system components forms part of an integrated multicellular barrier for defense against pathogens and dentin repair.

  20. Dental Fluorosis and Catalase Immunoreactivity of the Brain Tissues in Rats Exposed to High Fluoride Pre- and Postnatally.

    Science.gov (United States)

    Güner, Şirin; Uyar-Bozkurt, Süheyla; Haznedaroğlu, Eda; Menteş, Ali

    2016-11-01

    This study evaluated dental fluorosis of the incisors and immunoreactivity in the brain tissues of rats given chronic fluoride doses pre- and postnatally. Female rats were given drinking water with 0, 30 or 100 ppm fluoride ad libitum throughout gestation and the nursing period. In addition, 63 male offspring were treated with the same water regimens as the mothers after weaning and were followed for 1, 3 or 5 months. The upper and lower incisors were collected, and all teeth were examined under a stereomicroscope and scored by two blinded examiners using a modified rodent enamel fluorosis index. Cortical, hippocampal and cerebellar brain samples were evaluated morphologically and immunohistochemically. All fluoride-treated pups were born with low body weight (p = 0.001). All animals from the fluoride groups had enamel fluorosis with defects of various degrees. The increase in the dental fluorosis scores in the fluoride treatment groups was significant (p dental fluorosis had catalase immunoreactivity in the brain tissues, which may reflect the neurobehavioral toxicity of fluoride.

  1. Transplantation of human immature dental pulp stem cell in dogs with chronic spinal cord injury.

    Science.gov (United States)

    Feitosa, Matheus Levi Tajra; Sarmento, Carlos Alberto Palmeira; Bocabello, Renato Zonzini; Beltrão-Braga, Patrícia Cristina Baleeiro; Pignatari, Graciela Conceição; Giglio, Robson Fortes; Miglino, Maria Angelica; Orlandin, Jéssica Rodrigues; Ambrósio, Carlos Eduardo

    2017-07-01

    To investigate the therapeutic potential of human immature dental pulp stem cells in the treatment of chronic spinal cord injury in dogs. Three dogs of different breeds with chronic SCI were presented as animal clinical cases. Human immature dental pulp stem cells were injected at three points into the spinal cord, and the animals were evaluated by limb function and magnetic resonance imaging (MRI) pre and post-operative. There was significant improvement from the limb function evaluated by Olby Scale, though it was not supported by the imaging data provided by MRI and clinical sign and evaluation. Human dental pulp stem cell therapy presents promising clinical results in dogs with chronic spinal cord injuries, if used in association with physical therapy.

  2. Global surveillance of DDT and DDE levels in human tissues.

    Science.gov (United States)

    Jaga, Kushik; Dharmani, Chandrabhan

    2003-01-01

    The organochlorine insecticide dichlorodiphenyltrichloroethane (DDT) was initially introduced for control of vector-borne discases It was banned in the United States by the Environmental Protection Agency in 1972 because of potential harmful effects on humans, wildlife and the environment. Since it is a potential human carcinogen, the United Nations Environmental Program (UNEP) has recently restricted the use of DDT in developing countries until alternative methods of vector control are sought. DDT and its metabolite, dichlorodiphenyltrichloroethylene (DDE) are lipid soluble, and bioaccumulate more in human adipose tissue, than breast milk and serum. This article is a review of DDT and DDE levels in human tissues from different countries in the world. Data on p,p'-DDT and p,p'-DDE levels in human adipose tissue, breast milk and serum were selected from more recent literature. It was discovered that countries in Africa, Asia, and Latin America with more recent exposure to DDT and DDE have higher levels in human tissue than in Europe and the United States. The global concern for DDT and DDE is the environmental spread and persistence in the food chain. Hypothetically, there is a potential risk of harmful effects of DDT and DDE to human health. UNEP has cautiously taken action to protect human health, the environment and the earth from further destruction by persistent organic pollutants. Further exposure to DDT should be prevented to achieve this goal.

  3. Genetic effects on gene expression across human tissues

    NARCIS (Netherlands)

    Battle, Alexis; Brown, Christopher D.; Engelhardt, Barbara E.; Montgomery, Stephen B.; Aguet, François; Ardlie, Kristin G.; Cummings, Beryl B.; Gelfand, Ellen T.; Getz, Gad; Hadley, Kane; Handsaker, Robert E.; Huang, Katherine H.; Kashin, Seva; Karczewski, Konrad J.; Lek, Monkol; Li, Xiao; MacArthur, Daniel G.; Nedzel, Jared L.; Nguyen, Duyen T.; Noble, Michael S.; Segrè, Ayellet V.; Trowbridge, Casandra A.; Tukiainen, Taru; Abell, Nathan S.; Balliu, Brunilda; Barshir, Ruth; Basha, Omer; Bogu, Gireesh K.; Brown, Andrew; Castel, Stephane E.; Chen, Lin S.; Chiang, Colby; Conrad, Donald F.; Cox, Nancy J.; Damani, Farhan N.; Davis, Joe R.; Delaneau, Olivier; Dermitzakis, Emmanouil T.; Eskin, Eleazar; Ferreira, Pedro G.; Frésard, Laure; Gamazon, Eric R.; Garrido-Martín, Diego; Gewirtz, Ariel D. H.; Gliner, Genna; Gloudemans, Michael J.; Guigo, Roderic; Hall, Ira M.; Han, Buhm; He, Yuan; Hormozdiari, Farhad; Howald, Cedric; Kyung Im, Hae; Jo, Brian; Yong Kang, Eun; Kim, Yungil; Kim-Hellmuth, Sarah; Lappalainen, Tuuli; Li, Gen; Li, Xin; Liu, Boxiang; Mangul, Serghei; McCarthy, Mark I.; McDowell, Ian C.; Mohammadi, Pejman; Monlong, Jean; Muñoz-Aguirre, Manuel; Ndungu, Anne W.; Nicolae, Dan L.; Nobel, Andrew B.; Oliva, Meritxell; Ongen, Halit; Palowitch, John J.; Panousis, Nikolaos; Papasaikas, Panagiotis; Park, Yoson; Parsana, Princy; Payne, Anthony J.; Peterson, Christine B.; Quan, Jie; Reverter, Ferran; Sabatti, Chiara; Saha, Ashis; Sammeth, Michael; Scott, Alexandra J.; Shabalin, Andrey A.; Sodaei, Reza; Stephens, Matthew; Stranger, Barbara E.; Strober, Benjamin J.; Sul, Jae Hoon; Tsang, Emily K.; Urbut, Sarah; van de Bunt, Martijn; Wang, Gao; Wen, Xiaoquan; Wright, Fred A.; Xi, Hualin S.; Yeger-Lotem, Esti; Zappala, Zachary; Zaugg, Judith B.; Zhou, Yi-Hui; Akey, Joshua M.; Bates, Daniel; Chan, Joanne; Claussnitzer, Melina; Demanelis, Kathryn; Diegel, Morgan; Doherty, Jennifer A.; Feinberg, Andrew P.; Fernando, Marian S.; Halow, Jessica; Hansen, Kasper D.; Haugen, Eric; Hickey, Peter F.; Hou, Lei; Jasmine, Farzana; Jian, Ruiqi; Jiang, Lihua; Johnson, Audra; Kaul, Rajinder; Kellis, Manolis; Kibriya, Muhammad G.; Lee, Kristen; Billy Li, Jin; Li, Qin; Lin, Jessica; Lin, Shin; Linder, Sandra; Linke, Caroline; Liu, Yaping; Maurano, Matthew T.; Molinie, Benoit; Nelson, Jemma; Neri, Fidencio J.; Park, Yongjin; Pierce, Brandon L.; Rinaldi, Nicola J.; Rizzardi, Lindsay F.; Sandstrom, Richard; Skol, Andrew; Smith, Kevin S.; Snyder, Michael P.; Stamatoyannopoulos, John; Tang, Hua; Wang, Li; Wang, Meng; van Wittenberghe, Nicholas; Wu, Fan; Zhang, Rui; Nierras, Concepcion R.; Branton, Philip A.; Carithers, Latarsha J.; Guan, Ping; Moore, Helen M.; Rao, Abhi; Vaught, Jimmie B.; Gould, Sarah E.; Lockart, Nicole C.; Martin, Casey; Struewing, Jeffery P.; Volpi, Simona; Addington, Anjene M.; Koester, Susan E.; Little, A. Roger; Brigham, Lori E.; Hasz, Richard; Hunter, Marcus; Johns, Christopher; Johnson, Mark; Kopen, Gene; Leinweber, William F.; Lonsdale, John T.; McDonald, Alisa; Mestichelli, Bernadette; Myer, Kevin; Roe, Brian; Salvatore, Michael; Shad, Saboor; Thomas, Jeffrey A.; Walters, Gary; Washington, Michael; Wheeler, Joseph; Bridge, Jason; Foster, Barbara A.; Gillard, Bryan M.; Karasik, Ellen; Kumar, Rachna; Miklos, Mark; Moser, Michael T.; Jewell, Scott D.; Montroy, Robert G.; Rohrer, Daniel C.; Valley, Dana R.; Davis, David A.; Mash, Deborah C.; Undale, Anita H.; Smith, Anna M.; Tabor, David E.; Roche, Nancy V.; McLean, Jeffrey A.; Vatanian, Negin; Robinson, Karna L.; Sobin, Leslie; Barcus, Mary E.; Valentino, Kimberly M.; Qi, Liqun; Hunter, Steven; Hariharan, Pushpa; Singh, Shilpi; Um, Ki Sung; Matose, Takunda; Tomaszewski, Maria M.; Barker, Laura K.; Mosavel, Maghboeba; Siminoff, Laura A.; Traino, Heather M.; Flicek, Paul; Juettemann, Thomas; Ruffier, Magali; Sheppard, Dan; Taylor, Kieron; Trevanion, Stephen J.; Zerbino, Daniel R.; Craft, Brian; Goldman, Mary; Haeussler, Maximilian; Kent, W. James; Lee, Christopher M.; Paten, Benedict; Rosenbloom, Kate R.; Vivian, John; Zhu, Jingchun; Brown, Andrew A.; Nguyen, Duyen Y.; Sullivan, Timothy J.; Addington, Anjene; Koester, Susan; Lockhart, Nicole C.; Roe, Bryan; Valley, Dana; He, Amy Z.; Kang, Eun Yong; Quon, Gerald; Ripke, Stephan; Shimko, Tyler C.; Teran, Nicole A.; Zhang, Hailei; Bustamante, Carlos D.; Guigó, Roderic

    2017-01-01

    Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression

  4. A feasibility study of an in vitro differentiation potential toward insulin-producing cells by dental tissue-derived mesenchymal stem cells.

    Science.gov (United States)

    Sawangmake, Chenphop; Nowwarote, Nunthawan; Pavasant, Prasit; Chansiripornchai, Piyarat; Osathanon, Thanaphum

    2014-09-26

    Dental tissue-derived mesenchymal stem cells have been proposed as an alternative source for mesenchymal stem cells. Here, we investigated the differentiation ability toward insulin producing cells (IPCs) of human dental pulp stem cells (hDPSCs) and human periodontal ligament stem cells (hPDLSCs). These cells expressed mesenchymal stem cell surface markers and were able to differentiate toward osteogenic and adipogenic lineages. Upon 3 step-IPCs induction, hDPSCs exhibited more colony number than hPDLSCs. The mRNA upregulation of pancreatic endoderm/islet markers was noted. However, the significant increase was noted only for PDX-1, NGN-3, and INSULIN mRNA expression of hDPSCs. The hDPSCs-derived IPCs expressed PRO-INSULIN and released C-PEPTIDE upon glucose stimulation in dose-dependent manner. After IPCs induction, the Notch target, HES-1 and HEY-1, mRNA expression was markedly noted. Notch inhibition during the last induction step or throughout the protocol disturbed the ability of C-PEPTIDE release upon glucose stimulation. The results suggested that hDPSCs had better differentiation potential toward IPCs than hPDLSCs. In addition, the Notch signalling might involve in the differentiation regulation of hDPSCs into IPCs. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Iloprost up-regulates vascular endothelial growth factor expression in human dental pulp cells in vitro and enhances pulpal blood flow in vivo.

    Science.gov (United States)

    Limjeerajarus, Chalida Nakalekha; Osathanon, Thanaphum; Manokawinchoke, Jeeranan; Pavasant, Prasit

    2014-07-01

    Prostacyclin (PGI2) is a biomolecule capable of enhancing angiogenesis and cellular proliferation. We investigated the influence of a PGI2 analogue (iloprost) on dental pulp revascularization in vitro and in vivo by using human dental pulp cells (HDPCs) and a rat tooth injury model, respectively. Iloprost stimulated the human dental pulp cell mRNA expression of vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), and platelet-derived growth factor (PDGF) in a significant dose-dependent manner. This mRNA up-regulation was significantly inhibited by pretreatment with a PGI2 receptor antagonist and forskolin (a protein kinase A activator). In contrast, a protein kinase A inhibitor significantly enhanced the iloprost-induced mRNA expression of VEGF, FGF-2, and PDGF. Pretreatment with a fibroblast growth factor receptor inhibitor attenuated the VEGF, FGF-2, and PDGF mRNA expression, indicating opposing regulatory mechanisms. The effect of iloprost on the dental pulp was investigated in vivo by using a rat molar pulp injury model. The iloprost-treated group exhibited a significant increase in pulpal blood flow at 72 hours compared with control. The present study indicates that iloprost may be a candidate agent to promote neovascularization in dental pulp tissue, suggesting the potential clinical use of iloprost in vital pulp therapy. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  6. Cell proliferation-inducing protein 52/mitofilin is a surface antigen on undifferentiated human dental pulp stem cells.

    Science.gov (United States)

    Hwang, Hyo-In; Lee, Tae-Hyong; Jang, Young-Joo

    2015-06-01

    Dental pulp is a soft tissue located inside the hard part of a tooth and it contains a stem cell population that can regenerate damaged dentin and/or pulp itself. Human dental pulp stem cells (hDPSCs) are multipotent adult stem cells that have the potential to be differentiated into a variety of cell types. Although cells cultured primarily from pulp tissue show heterogeneous phenotypes and variable efficiency in their dentinogenic differentiation, proper selection markers, which are specific to hDPSCs, are essential for the osteo/dentinogenic study of human dental pulp cells. We had previously screened a set of undifferentiation-specific cell surface antibodies of hDPSCs through decoy immunization. In this study, we show that one of these surface monoclonal antibodies, 3C4, is bound to intact pulp cells in a highly undifferentiation-specific manner. The surface antigen protein bound specifically to 3C4 antibody was identified through direct immunoprecipitation and liquid chromatography-tandem mass spectrometry as the cell proliferation-inducing protein 52/Mitofilin, which is a protein of the inner mitochondrial membrane and is a possible antagonist to maintaining mitochondrial activation during differentiation. The expression of mitofilin/3C4 antigen dramatically decreased during differentiation, and the depletion of mitofilin/3C4 antigen induced the expression of osteogenic/dentinogenic markers earlier than during normal differentiation. The 3C4-positive cells isolated by a magnetic-activated cell sorting system were differentiated with a higher efficiency than 3C4-negative cells. These results indicate that finding mitochondria-related stem cell markers is valuable to be able to identify and isolate primitive stem cells.

  7. Immunolocalization of transforming growth factor alpha in normal human tissues

    DEFF Research Database (Denmark)

    Christensen, M E; Poulsen, Steen Seier

    1996-01-01

    anchorage-independent growth of normal cells and was, therefore, considered as an "oncogenic" growth factor. Later, its immunohistochemical presence in normal human cells as well as its biological effects in normal human tissues have been demonstrated. The aim of the present investigation was to elucidate...... the distribution of the growth factor in a broad spectrum of normal human tissues. Indirect immunoenzymatic staining methods were used. The polypeptide was detected with a polyclonal as well as a monoclonal antibody. The polyclonal and monoclonal antibodies demonstrated almost identical immunoreactivity. TGF......-alpha was found to be widely distributed in cells of normal human tissues derived from all three germ layers, most often in differentiated cells. In epithelial cells, three different kinds of staining patterns were observed, either diffuse cytoplasmic, cytoplasmic in the basal parts of the cells, or distinctly...

  8. Guided tissue regeneration ensures osseointegration of dental implants placed into extraction sockets. An experimental study in monkeys

    DEFF Research Database (Denmark)

    Warrer, L; Gotfredsen, K; Hjørting-Hansen, E

    1991-01-01

    The aim of the present study was to explore the possibility of achieving osseointegration of dental titanium implants, inserted into alveoli immediately after tooth extraction, by covering the recipient site with a teflon membrane. In each of 7 monkeys, mucoperiosteal flaps were raised...... present between the implant and the socket walls. In one side of the jaw, a membrane (Gore-Tex Augmentation Material) was adjusted to cover the implant. The implant in the other side of the jaw served as control and was only covered by the tissue flaps. Microscopic analysis after 3 months of healing...... on the buccal and palatal aspects of the maxillary molars in both sides of the jaw. The second molars were then extracted and self tapping titanium implants of the screw type (Astra Dental Implants) were inserted into the sockets of the largest roots. In the coronal portion of the sockets, a void was always...

  9. Human natural killer cell development in secondary lymphoid tissues

    Science.gov (United States)

    Freud, Aharon G.; Yu, Jianhua; Caligiuri, Michael A.

    2014-01-01

    For nearly a decade it has been appreciated that critical steps in human natural killer (NK) cell development likely occur outside of the bone marrow and potentially necessitate distinct microenvironments within extramedullary tissues. The latter include the liver and gravid uterus as well as secondary lymphoid tissues such as tonsils and lymph nodes. For as yet unknown reasons these tissues are naturally enriched with NK cell developmental intermediates (NKDI) that span a maturation continuum starting from an oligopotent CD34+CD45RA+ hematopoietic precursor cell to a cytolytic mature NK cell. Indeed despite the detection of NKDI within the aforementioned tissues, relatively little is known about how, why, and when these tissues may be most suited to support NK cell maturation and how this process fits in with other components of the human immune system. With the discovery of other innate lymphoid subsets whose immunophenotypes overlap with those of NKDI, there is also need to revisit and potentially re-characterize the basic immunophenotypes of the stages of the human NK cell developmental pathway in vivo. In this review, we provide an overview of human NK cell development in secondary lymphoid tissues and discuss the many questions that remain to be answered in this exciting field. PMID:24661538

  10. Ultrastructural Changes in Human Trabecular Meshwork Tissue after Laser Trabeculoplasty

    Directory of Open Access Journals (Sweden)

    Jeffrey R. SooHoo

    2015-01-01

    Full Text Available Purpose. To compare morphologic changes in human trabecular meshwork (TM after selective laser trabeculoplasty (SLT and argon laser trabeculoplasty (ALT. Design. Laboratory evaluation of ex vivo human eye TM after laser trabeculoplasty. Methods. Corneoscleral rims from human cadaver eyes were sectioned and treated with varying powers of either SLT or ALT. Specimens were examined using light microscopy, scanning electron microscopy (SEM, and transmission electron microscopy (TEM. Results. TEM of SLT at all powers resulted in disrupted TM cells with cracked and extracellular pigment granules. SEM of SLT samples treated at high power revealed tissue destruction with scrolling of trabecular beams. SEM of ALT-treated tissue showed increasing destruction with exposure to higher power. The presence or absence of “champagne” bubbles during SLT did not alter the histologic findings. Conclusions. SLT-treated human TM revealed disruption of TM cells with cracked, extracellular pigment granules, particularly at higher treatment powers. Tissue scrolling was noted at very high SLT energy levels. ALT-treated tissue showed significant damage to both the superficial and deeper TM tissues in a dose-dependent fashion. Further studies are needed to guide titration of treatment power to maximize the IOP-lowering effect while minimizing both energy delivered and damage to target tissues.

  11. Dental occlusion modifies gaze and posture stabilization in human subjects.

    Science.gov (United States)

    Gangloff, P; Louis, J P; Perrin, P P

    2000-11-03

    Repercussion of dental occlusion was tested upon postural and gaze stabilization, the latter with a visuo-motor task evaluated by shooting performances. Eighteen permit holders shooters and 18 controls were enrolled in this study. Postural control was evaluated in both groups according to four mandibular positions imposed by interocclusal splints: (i) intercuspal occlusion (IO), (ii) centric relation (CR), (iii) physiological side lateral occlusion and (iv) controlateral occlusion, in order to appreciate the impact of the splints upon orthostatism. Postural control and gaze stabilization quality decreased, from the best to the worst, with splints in CR, IO and lateral occlusion. In shooters, the improvement in postural control was parallel to superior shooting performance. A repercussion of dental occlusion upon proprioception and visual stabilization is suggested by these data.

  12. Evidence for xylitol 5-P production in human dental plaque

    Energy Technology Data Exchange (ETDEWEB)

    Waaler, S.M. (Department of Preclinical Techniques and Material Sciences and Department of Pedodontics, Dental Faculty, University of Oslo, Oslo (Norway))

    1992-01-01

    The Turku sugar studies indicated that xylitol may possess a caries-therapeutic effect. More recent data show that xylotol exhibits a bacteriostatic activity on a wide range of bacteria based on uptake and expulsion of xylitol. Intracellular xylitol 5-P appears to be a key substance associated with inhibition of bacterial metabolism by xylitol. This has been shown in studies with pure strains of bacteria, mainly Streptococcus mutans. The aim of the present study was to examine if production of xylitol 5-P occurs in freshly collected dental plaque which is exposed to labeled xylitol. Plaque extracts were analyzed by thin-layer chromatography combined with autoradiography and high performance liquid chromatography. Strong indications were obtained that xylitol 5-P is readily produced by dental plaque. No other significant xylitol metabolites were identified. The bacteriostatic properties of xylitol in plaque are a mechanism which may well account for the caries-therapeutic effect of xylitol. (au).

  13. The in vitro and in vivo influence of 4-META/MMA-TBB resin components on dental pulp tissues.

    Science.gov (United States)

    Inoue, T; Miyakoshi, S; Shimono, M

    2001-08-01

    The purpose of this study was to qualitate the penetration of the major components of 4-META/MMA-TBB adhesive resin (4-META resin) and to characterize their influence on the in vitro and in vivo wound healing of dental pulp tissues. Fresh 4-META resin was applied to rabbit mesentery; its components penetrated the mesentery to form three of layers, depending on the amounts of monomer components in the tissue. The superficial layer was a soft-tissue hybrid layer (STHL), the intermediate layer contained small particles of polymerized 4-META resin, while the deepest layer contained unpolymerized monomer components including MMA and butanol, which were detected by gas chromatography (GC). To characterize the in vivo effects of the deepest layer, we immersed the pulp tissue in MMA or in 5% 4-META/MMA and autotransplanted it to placement beneath a rabbit kidney capsule. The MMA-immersed pulp was positive for osteocalcin and presented osteodentin formation at 7 days, as did the untreated control pulp tissue. In contrast, the 5% 4-META/MMA-immersed pulp collapsed into the cell-deficient fibrous connective tissue, with slight calcification by 7 days and less osteodentin formation at 14 days. Analysis of these data suggests that MMA does not inhibit osteogenic activity of pulp tissue, while 5% 4-META/MMA does inhibit osteogenic activity to some extent.

  14. Identification of early microbial colonizers in human dental biofilm.

    Science.gov (United States)

    Li, J; Helmerhorst, E J; Leone, C W; Troxler, R F; Yaskell, T; Haffajee, A D; Socransky, S S; Oppenheim, F G

    2004-01-01

    To elucidate the first colonizers within in vivo dental biofilm and to establish potential population shifts that occur during the early phases of biofilm formation. A 'checkerboard' DNA-DNA hybridization assay was employed to identify 40 different bacterial strains. Dental biofilm samples were collected from 15 healthy subjects, 0, 2, 4 and 6 h after tooth cleaning and the composition of these samples was compared with that of whole saliva collected from the same individuals. The bacterial distribution in biofilm samples was distinct from that in saliva, confirming the selectivity of the adhesion process. In the very early stages, the predominant tooth colonizers were found to be Actinomyces species. The relative proportion of streptococci, in particular Streptococcus mitis and S. oralis, increased at the expense of Actinomyces species between 2 and 6 h while the absolute level of Actinomyces remained unaltered. Periodontal pathogens such as Tannerella forsythensis(Bacteroides forsythus), Porphyromonas gingivalis and Treponema denticola as well as Actinobacillus actinomycetemcomitans were present in extremely low levels at all the examined time intervals in this healthy group of subjects. The data provide a detailed insight into the bacterial population shifts occurring within the first few hours of biofilm formation and show that the early colonizers of the tooth surface predominantly consist of beneficial micro-organisms. The early colonizers of dental plaque are of great importance in the succession stages of biofilm formation and its overall effect on the oral health of the host.

  15. Diverse splicing patterns of exonized Alu elements in human tissues.

    Directory of Open Access Journals (Sweden)

    Lan Lin

    2008-10-01

    Full Text Available Exonization of Alu elements is a major mechanism for birth of new exons in primate genomes. Prior analyses of expressed sequence tags show that almost all Alu-derived exons are alternatively spliced, and the vast majority of these exons have low transcript inclusion levels. In this work, we provide genomic and experimental evidence for diverse splicing patterns of exonized Alu elements in human tissues. Using Exon array data of 330 Alu-derived exons in 11 human tissues and detailed RT-PCR analyses of 38 exons, we show that some Alu-derived exons are constitutively spliced in a broad range of human tissues, and some display strong tissue-specific switch in their transcript inclusion levels. Most of such exons are derived from ancient Alu elements in the genome. In SEPN1, mutations of which are linked to a form of congenital muscular dystrophy, the muscle-specific inclusion of an Alu-derived exon may be important for regulating SEPN1 activity in muscle. Realtime qPCR analysis of this SEPN1 exon in macaque and chimpanzee tissues indicates human-specific increase in its transcript inclusion level and muscle specificity after the divergence of humans and chimpanzees. Our results imply that some Alu exonization events may have acquired adaptive benefits during the evolution of primate transcriptomes.

  16. Predicting Tissue-Specific Enhancers in the Human Genome

    Energy Technology Data Exchange (ETDEWEB)

    Pennacchio, Len A.; Loots, Gabriela G.; Nobrega, Marcelo A.; Ovcharenko, Ivan

    2006-07-01

    Determining how transcriptional regulatory signals areencoded in vertebrate genomes is essential for understanding the originsof multi-cellular complexity; yet the genetic code of vertebrate generegulation remains poorly understood. In an attempt to elucidate thiscode, we synergistically combined genome-wide gene expression profiling,vertebrate genome comparisons, and transcription factor binding siteanalysis to define sequence signatures characteristic of candidatetissue-specific enhancers in the human genome. We applied this strategyto microarray-based gene expression profiles from 79 human tissues andidentified 7,187 candidate enhancers that defined their flanking geneexpression, the majority of which were located outside of knownpromoters. We cross-validated this method for its ability to de novopredict tissue-specific gene expression and confirmed its reliability in57 of the 79 available human tissues, with an average precision inenhancer recognition ranging from 32 percent to 63 percent, and asensitivity of 47 percent. We used the sequence signatures identified bythis approach to assign tissue-specific predictions to ~;328,000human-mouse conserved noncoding elements in the human genome. Byoverlapping these genome-wide predictions with a large in vivo dataset ofenhancers validated in transgenic mice, we confirmed our results with a28 percent sensitivity and 50 percent precision. These results indicatethe power of combining complementary genomic datasets as an initialcomputational foray into the global view of tissue-specific generegulation in vertebrates.

  17. In vitro proliferation and osteogenic differentiation of human dental pulp stem cells in injectable thermo-sensitive chitosan/β-glycerophosphate/hydroxyapatite hydrogel.

    Science.gov (United States)

    Chen, Yantian; Zhang, Fengli; Fu, Qiang; Liu, Yong; Wang, Zejian; Qi, Nianmin

    2016-09-01

    Injectable thermo-sensitive hydrogels have a potential application in bone tissue engineering for their sensitivities and minimal invasive properties. Human dental pulp stem cells have been considered a promising tool for tissue reconstruction. The objective of this study was to investigate the proliferation and osteogenic differentiation of dental pulp stem cells in injectable thermo-sensitive chitosan/β-glycerophosphate/hydroxyapatite hydrogel in vitro. The chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel were prepared using the sol-gel method. The injectability of chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel was measured using a commercial disposable syringe. Scanning electron microscopy was used to observe the inner structure of hydrogels. Then dental pulp stem cells were seeded in chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel, respectively. The growth of dental pulp stem cells was periodically observed under an inverted microscope. The proliferation of dental pulp stem cells was detected by using an Alamar Blue kit, while cell apoptosis was determined by using a Live/Dead Viability/Cytotoxicity kit. The osteogenic differentiations of dental pulp stem cells in chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel were evaluated by alkaline phosphatase activity assay and mRNA expression of osteogenesis gene for 21 days in osteogenic medium. The results indicated that there was no significant difference between chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel in injectability. Cells within the chitosan/β-glycerophosphate/hydroxyapatite hydrogel displayed a typical adherent cell morphology and rapid proliferation with high cellular viability after 14 days of culture. Dental pulp stem cells seeded in chitosan

  18. Mechanical changes in human dental pulp stem cells during early odontogenic differentiation.

    Science.gov (United States)

    Jones, Taneka D; Naimipour, Hamed; Sun, Shan; Cho, Michael; Alapati, Satish B

    2015-01-01

    Cell adhesion and migration in bioactive scaffolds require actin cytoskeleton remodeling and focal adhesion formation. Additionally, human dental pulp stem cells (hDPSCs) undergo several changes in their mechanical properties during odontogenic differentiation. The effect of factors essential for odontogenesis on actin stress fiber elasticity and focal adhesion formation is not known. Live hDPSCs cultured in odontogenic media were imaged for cytoskeleton changes using an atomic force microscope. The Young's modulus (kPa) of the cytoskeleton was recorded as a function of culture medium for 10 days. Focal adhesion formation was assessed using immunofluorescence. Cultured hDPSCs were incubated with a monoclonal vinculin antibody, and filamentous actins were visualized using 0.5 μmol/L phalloidin. Cytoskeletal elasticity significantly increased in response to odontogenic media. Both the number and physical size of focal adhesions in hDPSCs also increased. Up-regulation of vinculin expression was evident. The increase in the formation of focal adhesions was consistent with actin remodeling to stress fibers. Our findings suggest that hDPSCs firmly attach to the glass substrate in response to odontogenic media. Successful regeneration of pulp-dentin tissue using biomimetic scaffolds will likely require cell-extracellular matrix interactions influenced by biochemical induction factors. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Synchrotron X-ray diffraction characterization of healthy and fluorotic human dental enamel

    Science.gov (United States)

    Colaço, M. V.; Barroso, R. C.; Porto, I. M.; Gerlach, R. F.; Costa, F. N.; Braz, D.; Droppa, R.; de Sousa, F. B.

    2012-10-01

    With the introduction of fluoride as the main anticaries agent used in preventive dentistry, and perhaps an increase in fluoride in our food chain, dental fluorosis has become an increasing world-wide problem. Visible signs of fluorosis begin to become obvious on the enamel surface as opacities, implying some porosity in the tissue. The mechanisms that conduct the formation of fluorotic enamel are unknown, but should involve modifications in the basic physical-chemistry reactions of demineralization and remineralisation of the enamel of the teeth, which is the same reaction of formation of the enamel's hydroxyapatite (HAp) in the maturation phase. The increase of the amount of fluoride inside of the apatite will result in gradual increase of the lattice parameters. The aim of this work is to characterize the healthy and fluorotic enamel in human tooth using Synchrotron X-ray diffraction. All the scattering profile measurements were carried out at the X-ray diffraction beamline (XRD1) at the Brazilian Synchrotron Light Laboratory—LNLS, Campinas, Brazil. X-ray diffraction experiments were performed both in powder samples and polished surfaces. The powder samples were analyzed to obtain the characterization of a typical healthy enamel pattern. The polished surfaces were analyzed in specific areas that have been identified as fluorotic ones. X-ray diffraction data were obtained for all samples and these data were compared with the control samples and also with the literature data.

  20. Tissue engineering and surgery: from translational studies to human trials

    Directory of Open Access Journals (Sweden)

    Vranckx Jan Jeroen

    2017-06-01

    Full Text Available Tissue engineering was introduced as an innovative and promising field in the mid-1980s. The capacity of cells to migrate and proliferate in growth-inducing medium induced great expectancies on generating custom-shaped bioconstructs for tissue regeneration. Tissue engineering represents a unique multidisciplinary translational forum where the principles of biomaterial engineering, the molecular biology of cells and genes, and the clinical sciences of reconstruction would interact intensively through the combined efforts of scientists, engineers, and clinicians. The anticipated possibilities of cell engineering, matrix development, and growth factor therapies are extensive and would largely expand our clinical reconstructive armamentarium. Application of proangiogenic proteins may stimulate wound repair, restore avascular wound beds, or reverse hypoxia in flaps. Autologous cells procured from biopsies may generate an ‘autologous’ dermal and epidermal laminated cover on extensive burn wounds. Three-dimensional printing may generate ‘custom-made’ preshaped scaffolds – shaped as a nose, an ear, or a mandible – in which these cells can be seeded. The paucity of optimal donor tissues may be solved with off-the-shelf tissues using tissue engineering strategies. However, despite the expectations, the speed of translation of in vitro tissue engineering sciences into clinical reality is very slow due to the intrinsic complexity of human tissues. This review focuses on the transition from translational protocols towards current clinical applications of tissue engineering strategies in surgery.

  1. Comparative gene-expression analysis of the dental follicle and periodontal ligament in humans.

    Directory of Open Access Journals (Sweden)

    Hyo-Seol Lee

    Full Text Available The human dental follicle partially differentiates into the periodontal ligament (PDL, but their biological functions are different. The gene-expression profiles of the dental follicle and PDL were compared using the cDNA microarray technique. Microarray analysis identified 490 genes with a twofold or greater difference in expression, 365 and 125 of which were more abundant in the dental follicle and PDL, respectively. The most strongly expressed genes in the dental follicle were those related to bone development and remodeling (EGFL6, MMP8, FRZB, and NELL1, apoptosis and chemotaxis (Nox4, CXCL13, and CCL2, and tooth and embryo development (WNT2, PAX3, FGF7, AMBN, AMTN, and SLC4A4, while in the PDL it was the tumor-suppressor gene WIF1. Genes related to bone development and remodeling (STMN2, IBSP, BMP8A, BGLAP, ACP5, OPN, BMP3, and TM7SF4 and wound healing (IL1, IL8, MMP3, and MMP9 were also more strongly expressed in the PDL than in the dental follicle. In selected genes, a comparison among cDNA microarray, real-time reverse-transcription polymerase chain reaction, and immunohistochemical staining confirmed similar relative gene expressions. The gene-expression profiles presented here identify candidate genes that may enable differentiation between the dental follicle and PDL.

  2. Variability in responses observed in human white adipose tissue models.

    Science.gov (United States)

    Abbott, Rosalyn D; Borowsky, Francis E; Alonzo, Carlo A; Zieba, Adam; Georgakoudi, Irene; Kaplan, David L

    2017-09-06

    Obesity is a risk factor for a myriad of diseases including diabetes, cardiovascular dysfunction, cirrhosis, and cancer, and there is a need for new systems to study how excess adipose tissue relates to the onset of disease processes. This study provides proof-of-concept patient-specific tissue models of human white adipose tissue to accommodate the variability in human samples. Our 3D tissue engineering approach established lipolytic responses and changes in insulin-stimulated glucose uptake from small volumes of human lipoaspirate, making this methodology useful for patient specific sample source assessments of treatment strategies, drug responses, disease mechanisms, and other responses that vary between patients. Mature unilocular cells were maintained ex vivo in silk porous scaffolds for up to a month of culture and imaged non-invasively with coherent anti-Stokes Raman scattering. Interestingly, differences in responsiveness between tissues were observed in terms of magnitude of lipolysis, ability to suppress lipolysis, differences in glucose uptake, and lipid droplet size. Body mass index was not a factor in determining tissue responsiveness; rather, it is speculated that other unknown variables in the backgrounds of different patients (ethnicity, athleticism, disease history, lifestyle choices, etc.) likely had a more significant effect on the observed differences. This study reinforces the need to account for the variability in backgrounds and genetics within the human population to determine adipose tissue responsiveness. In the future, this tissue system could be used to inform individualized care strategies-enhancing therapeutic precision, improving patient outcomes, and reducing clinical costs. Copyright © 2017 John Wiley & Sons, Ltd.

  3. Engineered human broncho-epithelial tissue-like assemblies

    Science.gov (United States)

    Goodwin, Thomas J. (Inventor)

    2012-01-01

    Three-dimensional human broncho-epithelial tissue-like assemblies (TLAs) are produced in a rotating wall vessel (RWV) with microcarriers by coculturing mesenchymal bronchial-tracheal cells (BTC) and bronchial epithelium cells (BEC). These TLAs display structural characteristics and express markers of in vivo respiratory epithelia. TLAs are useful for screening compounds active in lung tissues such as antiviral compounds, cystic fibrosis treatments, allergens, and cytotoxic compounds.

  4. Human Papilloma Virus (HPV) Oral Prevalence in Scotland (HOPSCOTCH): A Feasibility Study in Dental Settings

    Science.gov (United States)

    Conway, David I.; Robertson, Chris; Gray, Heather; Young, Linda; McDaid, Lisa M.; Winter, Andrew J.; Campbell, Christine; Pan, Jiafeng; Kavanagh, Kimberley; Kean, Sharon; Bhatia, Ramya; Cubie, Heather; Clarkson, Jan E.; Bagg, Jeremy; Pollock, Kevin G.; Cuschieri, Kate

    2016-01-01

    The purpose of this study was to test the feasibility of undertaking a full population investigation into the prevalence, incidence, and persistence of oral Human Papilloma Virus (HPV) in Scotland via dental settings. Male and female patients aged 16–69 years were recruited by Research Nurses in 3 primary care and dental outreach teaching centres and 2 General Dental Practices (GDPs), and by Dental Care Teams in 2 further GDPs. Participants completed a questionnaire (via an online tablet computer or paper) with socioeconomic, lifestyle, and sexual history items; and were followed up at 6-months for further questionnaire through appointment or post/online. Saline oral gargle/rinse samples, collected at baseline and follow-up, were subject to molecular HPV genotyping centrally. 1213 dental patients were approached and 402 individuals consented (participation rate 33.1%). 390 completed the baseline questionnaire and 380 provided a baseline oral specimen. Follow-up rate was 61.6% at 6 months. While recruitment was no different in Research Nurse vs Dental Care Team models the Nurse model ensured more rapid recruitment. There were relatively few missing responses in the questionnaire and high levels of disclosure of risk behaviours (99% answered some of the sexual history questions). Data linkage of participant data to routine health records including HPV vaccination data was successful with 99.1% matching. Oral rinse/gargle sample collection and subsequent HPV testing was feasible. Preliminary analyses found over 95% of samples to be valid for molecular HPV detection prevalence of oral HPV infection of 5.5% (95%CI 3.7, 8.3). It is feasible to recruit and follow-up dental patients largely representative / reflective of the wider population, suggesting it would be possible to undertake a study to investigate the prevalence, incidence, and determinants of oral HPV infection in dental settings. PMID:27861508

  5. Human Papilloma Virus (HPV) Oral Prevalence in Scotland (HOPSCOTCH): A Feasibility Study in Dental Settings.

    Science.gov (United States)

    Conway, David I; Robertson, Chris; Gray, Heather; Young, Linda; McDaid, Lisa M; Winter, Andrew J; Campbell, Christine; Pan, Jiafeng; Kavanagh, Kimberley; Kean, Sharon; Bhatia, Ramya; Cubie, Heather; Clarkson, Jan E; Bagg, Jeremy; Pollock, Kevin G; Cuschieri, Kate

    2016-01-01

    The purpose of this study was to test the feasibility of undertaking a full population investigation into the prevalence, incidence, and persistence of oral Human Papilloma Virus (HPV) in Scotland via dental settings. Male and female patients aged 16-69 years were recruited by Research Nurses in 3 primary care and dental outreach teaching centres and 2 General Dental Practices (GDPs), and by Dental Care Teams in 2 further GDPs. Participants completed a questionnaire (via an online tablet computer or paper) with socioeconomic, lifestyle, and sexual history items; and were followed up at 6-months for further questionnaire through appointment or post/online. Saline oral gargle/rinse samples, collected at baseline and follow-up, were subject to molecular HPV genotyping centrally. 1213 dental patients were approached and 402 individuals consented (participation rate 33.1%). 390 completed the baseline questionnaire and 380 provided a baseline oral specimen. Follow-up rate was 61.6% at 6 months. While recruitment was no different in Research Nurse vs Dental Care Team models the Nurse model ensured more rapid recruitment. There were relatively few missing responses in the questionnaire and high levels of disclosure of risk behaviours (99% answered some of the sexual history questions). Data linkage of participant data to routine health records including HPV vaccination data was successful with 99.1% matching. Oral rinse/gargle sample collection and subsequent HPV testing was feasible. Preliminary analyses found over 95% of samples to be valid for molecular HPV detection prevalence of oral HPV infection of 5.5% (95%CI 3.7, 8.3). It is feasible to recruit and follow-up dental patients largely representative / reflective of the wider population, suggesting it would be possible to undertake a study to investigate the prevalence, incidence, and determinants of oral HPV infection in dental settings.

  6. Nigerian dental technology students and human immunodeficiency virus infection: knowledge, misconceptions and willingness to care.

    Science.gov (United States)

    Azodo, Cc; Omili, Ma; Akeredolu, Pa

    2014-05-01

    The rehabilitative dental care is important for maintaining adequate nutrition, guarding against wasting syndrome and malnutrition among human immunodeficiency virus (HIV)-infected individuals. The aim of this study is to determine the Nigerian dental technology students' knowledge and misconceptions about HIV infection and their willingness to care for HIV-infected patients. This descriptive cross-sectional study of dental technology students of Federal School of Dental Therapy and Technology Enugu, Nigeria was conducted in 2010. Data was subjected to descriptive, non-parametric and parametric statistics using the statistical package for the social sciences (SPSS) version 17.0 (Chicago Illinois, USA). P misconceptions. Specifically, the misconceptions about HIV transmission through a mosquito bite (P = 0.02) and shaking of hands (P = 0.03) were higher among respondents in the higher class than those in lower class. However, 10.6% (21/198), 6.1% (12/198) and 4.0% (8/198) of the respondents erroneous described HIV as harmless, self-limitation and antibiotics responsive infection respectively. Of the respondents, 78.8% (156/198) and 83.3% (165/198) of them expressed willingness to care for HIV-infected patients and expressed need for training in the clinical care of HIV-infected patients respectively. Overall, the respondents opined that the dental therapists are the most suitable dental professional to pass HIV-related information to patients in the dental setting ahead of dentists and dental surgery assistants. The expressed willingness to care for HIV-infected patients, knowledge about the mode of HIV transmission and prevention among the respondents were high with existent misconceptions. There were no significant differences in the knowledge about HIV infection and willingness to care for HIV-infected patients among respondents in the lower class and those in upper class.

  7. Sodium channel Nav1.7 immunoreactivity in painful human dental pulp and burning mouth syndrome

    Directory of Open Access Journals (Sweden)

    Yiangou Yiangos

    2010-06-01

    Full Text Available Abstract Background Voltage gated sodium channels Nav1.7 are involved in nociceptor nerve action potentials and are known to affect pain sensitivity in clinical genetic disorders. Aims and Objectives To study Nav1.7 levels in dental pulpitis pain, an inflammatory condition, and burning mouth syndrome (BMS, considered a neuropathic orofacial pain disorder. Methods Two groups of patients were recruited for this study. One group consisted of patients with dental pulpitis pain (n = 5 and controls (n = 12, and the other patients with BMS (n = 7 and controls (n = 10. BMS patients were diagnosed according to the International Association for the Study of Pain criteria; a pain history was collected, including the visual analogue scale (VAS. Immunohistochemistry with visual intensity and computer image analysis were used to evaluate levels of Nav1.7 in dental pulp tissue samples from the dental pulpitis group, and tongue biopsies from the BMS group. Results There was a significantly increased visual intensity score for Nav1.7 in nerve fibres in the painful dental pulp specimens, compared to controls. Image analysis showed a trend for an increase of the Nav1.7 immunoreactive % area in the painful pulp group, but this was not statistically significant. When expressed as a ratio of the neurofilament % area, there was a strong trend for an increase of Nav1.7 in the painful pulp group. Nav1.7 immunoreactive fibres were seen in abundance in the sub-mucosal layer of tongue biopsies, with no significant difference between BMS and controls. Conclusion Nav1.7 sodium channel may play a significant role in inflammatory dental pain. Clinical trials with selective Nav1.7 channel blockers should prioritise dental pulp pain rather than BMS.

  8. Advancing biomaterials of human origin for tissue engineering

    Science.gov (United States)

    Chen, Fa-Ming; Liu, Xiaohua

    2015-01-01

    Biomaterials have played an increasingly prominent role in the success of biomedical devices and in the development of tissue engineering, which seeks to unlock the regenerative potential innate to human tissues/organs in a state of deterioration and to restore or reestablish normal bodily function. Advances in our understanding of regenerative biomaterials and their roles in new tissue formation can potentially open a new frontier in the fast-growing field of regenerative medicine. Taking inspiration from the role and multi-component construction of native extracellular matrices (ECMs) for cell accommodation, the synthetic biomaterials produced today routinely incorporate biologically active components to define an artificial in vivo milieu with complex and dynamic interactions that foster and regulate stem cells, similar to the events occurring in a natural cellular microenvironment. The range and degree of biomaterial sophistication have also dramatically increased as more knowledge has accumulated through materials science, matrix biology and tissue engineering. However, achieving clinical translation and commercial success requires regenerative biomaterials to be not only efficacious and safe but also cost-effective and convenient for use and production. Utilizing biomaterials of human origin as building blocks for therapeutic purposes has provided a facilitated approach that closely mimics the critical aspects of natural tissue with regard to its physical and chemical properties for the orchestration of wound healing and tissue regeneration. In addition to directly using tissue transfers and transplants for repair, new applications of human-derived biomaterials are now focusing on the use of naturally occurring biomacromolecules, decellularized ECM scaffolds and autologous preparations rich in growth factors/non-expanded stem cells to either target acceleration/magnification of the body's own repair capacity or use nature's paradigms to create new tissues for

  9. Advancing biomaterials of human origin for tissue engineering.

    Science.gov (United States)

    Chen, Fa-Ming; Liu, Xiaohua

    2016-02-01

    Biomaterials have played an increasingly prominent role in the success of biomedical devices and in the development of tissue engineering, which seeks to unlock the regenerative potential innate to human tissues/organs in a state of deterioration and to restore or reestablish normal bodily function. Advances in our understanding of regenerative biomaterials and their roles in new tissue formation can potentially open a new frontier in the fast-growing field of regenerative medicine. Taking inspiration from the role and multi-component construction of native extracellular matrices (ECMs) for cell accommodation, the synthetic biomaterials produced today routinely incorporate biologically active components to define an artificial in vivo milieu with complex and dynamic interactions that foster and regulate stem cells, similar to the events occurring in a natural cellular microenvironment. The range and degree of biomaterial sophistication have also dramatically increased as more knowledge has accumulated through materials science, matrix biology and tissue engineering. However, achieving clinical translation and commercial success requires regenerative biomaterials to be not only efficacious and safe but also cost-effective and convenient for use and production. Utilizing biomaterials of human origin as building blocks for therapeutic purposes has provided a facilitated approach that closely mimics the critical aspects of natural tissue with regard to its physical and chemical properties for the orchestration of wound healing and tissue regeneration. In addition to directly using tissue transfers and transplants for repair, new applications of human-derived biomaterials are now focusing on the use of naturally occurring biomacromolecules, decellularized ECM scaffolds and autologous preparations rich in growth factors/non-expanded stem cells to either target acceleration/magnification of the body's own repair capacity or use nature's paradigms to create new tissues for

  10. [Emdogain regulates the expression of bone sialoprotein gene in human dental pulp cells].

    Science.gov (United States)

    Chen, Zhen; Wang, Shuang; Wang, Ying-hui; Gao, Ping

    2013-09-01

    To analyze the effects of emdogain(EMD) on the expression of the bone sialoprotein(BSP) gene in human dental pulp cells and to elucidate the molecular mechanism of BSP gene regulated by EMD. Human dental pulp was harvested from premolars freshly extracted for orthodontic purpose and cultured. Cells were divided into different concentrations (25, 50, 100 and 250 mg/L) of EMD and control groups (Dulbecco's modified Eagle's medium). Total RNA of cells was extracted. Human BSP mRNA levels was detected with the real-time PCR. Regulations of EMD on human BSP protein levels were detected with Western blotting. In the real-time PCR, at the same time point, there were significant differences on BSP mRNA levels between 25, 50, 100 and 250 mg/L EMD groups (7 d:1.79 ± 0.03, 2.03 ± 0.10, 2.67 ± 0.08, 2.94 ± 0.07) and control group (7 d:1.06 ± 0.11) (P < 0.001); at the different time point (1, 3, 5 and 7 d), the same dose(250 mg/L) of EMD stimulated human dental pulp cells, BSP mRNA (2.30 ± 0.06, 2.65 ± 0.05, 2.76 ± 0.05, 2.94 ± 0.07) was increased (P < 0.05). Treatment of human dental pulp cells with EMD (250 mg/L) increased the protein levels. EMD increases BSP mRNA and protein levels in human dental pulp cells.

  11. OCT4B1 Regulates the Cellular Stress Response of Human Dental Pulp Cells with Inflammation

    Directory of Open Access Journals (Sweden)

    Lu Liu

    2017-01-01

    Full Text Available Introduction. Infection and apoptosis are combined triggers for inflammation in dental tissues. Octamer-binding transcription factor 4-B1 (OCT4B1, a novel spliced variant of OCT4 family, could respond to the cellular stress and possess antiapoptotic property. However, its specific role in dental pulpitis remains unknown. Methods. To investigate the effect of OCT4B1 on inflammation of dental pulp cells (DPCs, its expression in inflamed dental pulp tissues and DPCs was examined by in situ hybridization, real-time PCR, and FISH assay. OCT4B1 overexpressed DPCs model was established, confirmed by western blot and immunofluorescence staining, and then stimulated with Lipopolysaccharide (LPS. Apoptotic rate was determined by Hoechst/PI staining and FACS. Cell survival rate was calculated by CCK8 assay. Results. In situ hybridization, real-time PCR, and FISH assay revealed that OCT4B1 was extensively expressed in inflamed dental pulp tissues and DPCs with LPS stimulation. Western blot and immunofluorescence staining showed the expression of OCT4B1 and OCT4B increased after OCT4B1 transfection. Hoechst/PI staining and FACS demonstrated that less red/blue fluorescence was detected and apoptotic percentage decreased (3.45% after transfection. CCK8 demonstrated that the survival rate of pCDH-OCT4B1-flag cells increased. Conclusions. OCT4B1 plays an essential role in inflammation and apoptosis of DPCs. OCT4B might operate synergistically with OCT4B1 to reduce apoptosis.

  12. Hypoxia-Inducible Factor-1α: A Potential Factor for the Enhancement of Osseointegration between Dental Implants and Tissue-Engineered Bone

    Directory of Open Access Journals (Sweden)

    Duohong Zou

    2011-07-01

    Full Text Available Introduction: Tissue-engineered bones are widely utilized to protect healthy tissue, reduce pain, and increase the success rate of dental implants. one of the most challenging obstacles lies in obtaining effective os-seointegration between dental implants and tissue-engineered structures. Deficiencies in vascularization, osteogenic factors, oxygen, and other nutrients inside the tissue-engineered bone during the early stages following implantation all inhibit effective osseointe-gration. Oxygen is required for aerobic metabolism in bone and blood vessel tissues, but oxygen levels inside tissue-engineered bone are not suf-ficient for cell proliferation. HIF-1α is a pivotal regulator of hypoxic and ischemic vascular responses, driving transcriptional activation of hundreds of genes involved in vascular reactivity, angiogenesis, arteriogenesis, and osteogenesis.The hypothesis: Hypoxia-Inducible Factor-1α seems a potential factor for the enhancement of osseointegration between dental implants and tissue-engineered bone.Evaluation of the hypothesis: Enhancement of HIF-1α protein expression is recognized as the most promising approach for angiogenesis, because it can induce multiple angiogenic targets in a coordinated manner. Therefore, it will be a novel potential therapeutic methods targeting HIF-1α expression to enhance osseointegration be-tween dental implants and tissue-engineered bone.

  13. Application of Er:YAG and Er, Cr:YSGG lasers in cavity preparation for dental tissues: a literature review

    OpenAIRE

    Santos, Carla Raquel dos [UNESP; Tonetto, Mateus Rodrigues; Presoto, Cristina Dupim; Bandéca,Matheus Coelho; Oliveira Júnior, Osmir Batista de [UNESP; Calabrez-Filho, Saturnino [UNESP; Andrade,Marcelo Ferrarezi de

    2012-01-01

    The laser has been widely used in many specialties of dentistry and several wavelengths have been investigated as a substitute for high-speed handpiece. The purpose of this paper is to review the literature about the use of Er:YAG and Er,Cr:YSGG lasers in cavity preparation for dental tissues. Despite the differences in wavelength, pulse duration and energy, the morphological characteristics of the irradiated dentin surface with these lasers are comparable, as well as its effects as methods o...

  14. Drug-induced premature senescence model in human dental follicle stem cells.

    Science.gov (United States)

    Zhai, Yuanfen; Wei, Rongbin; Liu, Junjun; Wang, Huihui; Cai, Wenping; Zhao, Mengmeng; Hu, Yongguang; Wang, Shuwei; Yang, Tianshu; Liu, Xiaodong; Yang, Jianhua; Liu, Shangfeng

    2017-01-31

    Aging is identified by a progressive decline of physiological integrity leading to age-related degenerative diseases, but its causes is unclear. Human dental pulp stem cells (hDPSCs) has a remarkable rejuvenated capacity that relies on its resident stem cells. However, because of the lack of proper senescence models, exploration of the underlying molecular mechanisms has been hindered. Here, we established a cellular model utilizing a hydroxyurea (HU) treatment protocol and effectively induced Human dental pulp stem cells to undergo cellular senescence. Age-related phenotypic changes were identified by augmented senescence-associated-β-galactosidase (SA-β-gal) staining, declined proliferation and differentiation capacity, elevated G0/G1 cell cycle arrest, increased apoptosis and reactive oxygen species levels. Furthermore, we tested the expression of key genes in various DNA repair pathways including nonhomologous end-joining (NHEJ) and homologous recombination (HR) pathways. In addition, our results showed that Dental pulp stem cells from young donors are more resistant to apoptosis and exhibit increased non-homologous end joining activity compared to old donors. Further transcriptome analysis demonstrate that multiple pathways are involved in the HU-induced Dental pulp stem cells ageing, including genes associated with DNA damage and repair, mitochondrial dysfunction and increased reactive oxygen species levels. Taken together, the cellular model have important implications for understanding the molecular exploration of Dental pulp stem cells senescence and aging.

  15. Comparison of osteo/odontogenic differentiation of human adult dental pulp stem cells and stem cells from apical papilla in the presence of platelet lysate.

    Science.gov (United States)

    Abuarqoub, Duaa; Awidi, Abdalla; Abuharfeil, Nizar

    2015-10-01

    Human dental pulp cells (DPSCs) and stem cells from apical papilla have been used for the repair of damaged tooth tissues. Human platelet lysate (PL) has been suggested as a substitute for fetal bovine serum (FBS) for large scale expansion of dental stem cells. However, biological effects and optimal concentrations of PL for proliferation and differentiation of human dental stem cells remain to be elucidated. DPSCs and SCAP cells were isolated from impacted third molars of young healthy donors, at the stage of root development and identified by markers using flow cytometry. For comparison the cells were cultured in media containing PL (1%, 5% and 10%) and FBS, with subsequent induction for osteogenic/odontogenic differentiation. The cultures were analyzed for; morphology, growth characteristics, mineralization potential (Alizarin Red method) and differentiation markers using ELISA and real time -polymerase chain reaction (qPCR). The proliferation rates of DPSCs and SCAP significantly increased when cells were treated with 5% PL (7X doubling time) as compared to FBS. 5% PL also enhanced mineralized differentiation of DPSCs and SCAP, as indicated by the measurement of alkaline phosphatase activity, osteocalcin and osteopontin, calcium deposition and q-PCR. Our findings suggest that using 5% platelet lysate, proliferation and osteo/odontogenesis of DPSCs and SCAP for a short period of time (15 days), was significantly improved. This may imply its use as an optimum concentration for expansion of dental stem cells in bone regeneration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Transepithelial Transport of PAMAM Dendrimers Across Isolated Human Intestinal Tissue.

    Science.gov (United States)

    Hubbard, Dallin; Enda, Michael; Bond, Tanner; Moghaddam, Seyyed Pouya Hadipour; Conarton, Josh; Scaife, Courtney; Volckmann, Eric; Ghandehari, Hamidreza

    2015-11-02

    Poly(amido amine) (PAMAM) dendrimers have shown transepithelial transport across intestinal epithelial barrier in rats and across Caco-2 cell monolayers. Caco-2 models innately lack mucous barriers, and rat isolated intestinal tissue has been shown to overestimate human permeability. This study is the first report of transport of PAMAM dendrimers across isolated human intestinal epithelium. It was observed that FITC labeled G4-NH2 and G3.5-COOH PAMAM dendrimers at 1 mM concentration do not have a statistically higher permeability compared to free FITC controls in isolated human jejunum and colonic tissues. Mannitol permeability was increased at 10 mM concentrations of G3.5-COOH and G4-NH2 dendrimers. Significant histological changes in human colonic and jejunal tissues were observed at G3.5-COOH and G4-NH2 concentrations of 10 mM implying that dose limiting toxicity may occur at similar concentrations in vivo. The permeability through human isolated intestinal tissue in this study was compared to previous rat and Caco-2 permeability data. This study implicates that PAMAM dendrimer oral drug delivery may be feasible, but it may be limited to highly potent drugs.

  17. Augmentation of residual alveolar bone height with tissue engineering for dental implant placement

    Directory of Open Access Journals (Sweden)

    S M Balaji

    2014-01-01

    Full Text Available The challenge of correcting deficient vertical alveolar height for dental implant placement has been there since dental implants came in to regular clinical placement. The ability of various methods to increase the residual alveolar height has met with varying results. The primary reason is that the techniques were not quite successful in maintaining the required residual alveolar height. Use of Bone Morphogentic Protein, especially rhBMP-2 has been met with high degree of success in deficient vertical alveolar height in a mandibular ridge. The demonstration of this using a case has been presented here.

  18. Soft tissue wound healing at teeth, dental implants and the edentulous ridge when using barrier membranes, growth and differentiation factors and soft tissue substitutes.

    Science.gov (United States)

    Vignoletti, Fabio; Nunez, Javier; Sanz, Mariano

    2014-04-01

    To review the biological processes of wound healing following periodontal and periimplant plastic surgery when different technologies are used in a) the coverage of root and implant dehiscences, b) the augmentation of keratinized tissue (KT) and c) the augmentation of soft tissue volume. An electronic search from The National Library of Medicine (MEDLINE-PubMed) was performed: English articles with research focus in oral soft tissue regeneration, providing histological outcomes, either from animal experimental studies or human biopsy material were included. Barrier membranes, enamel matrix derivatives, growth factors, allogeneic and xenogeneic soft tissue substitutes have been used in soft tissue regeneration demonstrating different degrees of regeneration. In root coverage, these technologies were able to improve new attachment, although none has shown complete regeneration. In KT augmentation, tissue-engineered allogenic products and xenogeneic collagen matrixes demonstrated integration within the host connective tissue and promotion of keratinization. In soft tissue augmentation and peri-implant plastic surgery there are no histological data currently available. Soft tissue substitutes, growth differentiation factors demonstrated promising histological results in terms of soft tissue regeneration and keratinization, whereas there is a need for further studies to prove their added value in soft tissue augmentation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Differential inducibility of human and porcine dental pulp-derived cells into odontoblasts.

    Science.gov (United States)

    Tonomura, Akiko; Sumita, Yoshinori; Ando, Yusuke; Iejima, Daisuke; Kagami, Hideaki; Honda, Masaki J; Ueda, Minoru

    2007-01-01

    A robust method for generating odontoblasts from cultured dental pulp cells has not been established. In this study, efficient methods for deriving odontoblasts from cultured human and porcine dental pulp-derived cells were investigated with special attention to species differences. Cultured human cells showed relatively low alkaline phosphatase (ALP) activity in the presence of dexamethasone (Dex) and beta-glycerophosphate (beta-Gly). In contrast, the addition of 1,25-dihydroxyvitaminD(3) (VitD3) significantly increased the ALP activity. In porcine cells, beta-Gly alone or a combination of Dex and beta-Gly significantly increased ALP activity; however, addition of VitD3 reduced this activity. RT-PCR and Western blotting analysis revealed that the combination of three induction reagents on human cells significantly upregulates the expression of osteocalcin mRNA, and dentin sialoprotein. We propose that the combination of Dex, beta-Gly, and VitD3 is critical for differentiation of human dental pulp-derived cells into odontoblasts. In addition, the inducibility of dental pulp-derived cells presented remarkable species differences.

  20. The performance of human dental pulp stem cells on different three-dimensional scaffold materials.

    NARCIS (Netherlands)

    Zhang, W.; Walboomers, X.F.; Kuppevelt, A.H.M.S.M. van; Daamen, W.F.; Bian, Z.; Jansen, J.A.

    2006-01-01

    The aim of this study was to investigate the in vitro and in vivo behavior of human dental pulp stem cells (DPSCs) isolated from impacted third molars, when seeded onto different 3-dimensional (3-D) scaffold materials: i.e. a spongeous collagen, a porous ceramic, and a fibrous titanium mesh.

  1. Electrospun human keratin matrices as templates for tissue regeneration.

    Science.gov (United States)

    Sow, Wan Ting; Lui, Yuan Siang; Ng, Kee Woei

    2013-04-01

    The aim of this work was to study the feasibility of fabricating human hair keratin matrices through electrospinning and to evaluate the potential of these matrices for tissue regeneration. Keratin was extracted from human hair using Na2S and blended with poly(ethylene oxide) in the weight ratio of 60:1 for electrospinning. Physical morphology and chemical properties of the matrices were characterized using scanning electron microscopy and Fourier transform infrared spectroscopy, respectively. Cell viability and morphology of murine and human fibroblasts cultured on the matrices were evaluated through the Live/Dead(®) assay and scanning electron microscopy. Electrospun keratin matrices were successfully produced without affecting the chemical conformation of keratin. Fibroblasts cultured on keratin matrices showed healthy morphology and penetration into matrices at day 7. Electrospun human hair keratin matrices provide a bioinductive and structural environment for cell growth and are thus attractive as alternative templates for tissue regeneration.

  2. Human perception of dental porcelain translucency correlated to spectrophotometric measurements.

    Science.gov (United States)

    Liu, Min-Chieh; Aquilino, Steven A; Lund, Peter S; Vargas, Marcos A; Diaz-Arnold, Ana M; Gratton, David G; Qian, Fang

    2010-04-01

    This study evaluated the relationship between instrumental measurements and subjective visual assessment of differences in dental porcelain translucency. Unshaded feldspathic porcelain was used with controlled amounts of tin oxide to create two groups of 12-mm diameter disks with incremental changes in opacity. Contrast ratio (CR = Yb/Yw) was determined with a spectrophotometer, and used as a measure of porcelain translucency (Group A = 0.20 to 0.40; Group B = 0.6-0.8). Within each group, there were 14 specimens with 11 CRs. Three observer groups (first year dental students, residents, faculty with >10 years of shade matching experience) were recruited to assess the translucency between porcelain disks under two lighting conditions (reflected light, transmitted light). Each subject's ability to distinguish between specimens of differing translucency was determined. Descriptive statistics and three-way ANOVA followed by a post-hoc Tukey-Kramer test were used to evaluate the translucency perception threshold (TPT) of subjects (alpha= 0.05). The overall mean TPT (DeltaC) was 0.07, while 50% of the subjects could perceive a 0.06 CR difference between porcelain specimens. Three-way ANOVA revealed a significant difference in translucency perception among the observer groups (p or =10 years) significantly improved the ability to perceive differences in translucency; however, neither the viewing condition nor porcelain opacity affected the perceived translucency threshold.

  3. Magnetic studies of iron-entities in human tissues

    Energy Technology Data Exchange (ETDEWEB)

    Slawska-Waniewska, A. E-mail: slaws@ifpan.edu.pl; Mosiniewicz-Szablewska, E.; Nedelko, N.; Galazka-Friedman, J.; Friedman, A

    2004-05-01

    Iron-entities in the human liver, brain and blood tissues have been investigated by means of EPR spectroscopy and magnetization measurements over the temperature range 4-300 K. The identification of the most typical forms of iron in the human body (i.e. isolated Fe-ions bonded in hemoglobin and transferrin as well as exchange coupled Fe-ions in nanosized ferritin cores) is presented.

  4. A Simplified and Systematic Method to Isolate, Culture, and Characterize Multiple Types of Human Dental Stem Cells from a Single Tooth.

    Science.gov (United States)

    Bakkar, Mohammed; Liu, Younan; Fang, Dongdong; Stegen, Camille; Su, Xinyun; Ramamoorthi, Murali; Lin, Li-Chieh; Kawasaki, Takako; Makhoul, Nicholas; Pham, Huan; Sumita, Yoshinori; Tran, Simon D

    2017-01-01

    This chapter describes a simplified method that allows the systematic isolation of multiple types of dental stem cells such as dental pulp stem cells (DPSC), periodontal ligament stem cells (PDLSC), and stem cells of the apical papilla (SCAP) from a single tooth. Of specific interest is the modified laboratory approach to harvest/retrieve the dental pulp tissue by minimizing trauma to DPSC by continuous irrigation, reduction of frictional heat from the bur rotation, and reduction of the bur contact time with the dentin. Also, the use of a chisel and a mallet will maximize the number of live DPSC for culture. Steps demonstrating the potential for multiple cell differentiation lineages of each type of dental stem cell into either osteocytes, adipocytes, or chondrocytes are described. Flow cytometry, with a detailed strategy for cell gating and analysis, is described to verify characteristic markers of human mesenchymal multipotent stromal cells (MSC) from DPSC, PDLSC, or SCAP for subsequent experiments in cell therapy and in tissue engineering. Overall, this method can be adapted to any laboratory with a general setup for cell culture experiments.

  5. Distribution of class ii major histocompatibility complex antigenexpressing cells in human dental pulp with carious lesions

    Directory of Open Access Journals (Sweden)

    Tetiana Haniastuti

    2012-09-01

    Full Text Available Background: Dental caries is a bacterial infection which causes destruction of the hard tissues of the tooth. Exposure of the dentin to the oral environment as a result of caries inevitably results in a cellular response in the pulp. The major histocompatibility complex (MHC is a group of genes that code for cell-surface histocompatibility antigens. Cells expressing class II MHC molecules participate in the initial recognition and the processing of antigenic substances to serve as antigen-presenting cells. Purpose: The aim of the study was to elucidate the alteration in the distribution of class II MHC antigen-expressing cells in human dental pulp as carious lesions progressed toward the pulp. Methods: Fifteen third molars with caries at the occlusal site at various stages of decay and 5 intact third molars were extracted and used in this study. Before decalcifying with 10% EDTA solution (pH 7.4, all the samples were observed by micro-computed tomography to confirm the lesion condition three-dimensionally. The specimens were then processed for cryosection and immunohistochemistry using an anti-MHC class II monoclonal antibody. Results: Class II MHC antigen-expressing cells were found both in normal and carious specimens. In normal tooth, the class II MHC-immunopositive cells were observed mainly at the periphery of the pulp tissue. In teeth with caries, class II MHC-immunopositive cells were located predominantly subjacent to the carious lesions. As the caries progressed, the number of class II MHC antigen-expressing cells was increased. Conclusion: The depth of carious lesions affects the distribution of class II MHC antigen-expressing cells in the dental pulp.Latar belakang: Karies merupakan penyakit infeksi bakteri yang mengakibatkan destruksi jaringan keras gigi. Dentin yang terbuka akibat karies akan menginduksi respon imun seluler pada pulpa. Kompleks histokompatibilitas utama (MHC merupakan sekumpulan gen yang mengkode histokompatibilitas

  6. Some observations on the trace element concentrations in human dental enamel.

    Science.gov (United States)

    Lane, D W; Peach, D F

    1997-01-01

    The concentration of trace elements has been measured for dental enamel from 86 healthy human teeth using particle-induced X-ray emission (PIXE). The majority of the teeth (n = 70) were collected from dentists in the county of Oxfordshire in the United Kingdom, although a smaller group (n = 16) were collected from Cornwall. The elements K, Ca, Mn, Fe, Co, Ni, Cu, Zn, Sr, Pb, and Hg have been detected and statistically analyzed by grouping according to sex, age, and geographical location. The concentrations of Fe and Cu were found to be lower in the teeth from female donors (P apatite (HAP) within the dental enamel.

  7. Pluripotency of Stem Cells from Human Exfoliated Deciduous Teeth for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Vinicius Rosa

    2016-01-01

    Full Text Available Stem cells from human exfoliated deciduous teeth (SHED are highly proliferative pluripotent cells that can be retrieved from primary teeth. Although SHED are isolated from the dental pulp, their differentiation potential is not limited to odontoblasts only. In fact, SHED can differentiate into several cell types including neurons, osteoblasts, adipocytes, and endothelial cells. The high plasticity makes SHED an interesting stem cell model for research in several biomedical areas. This review will discuss key findings about the characterization and differentiation of SHED into odontoblasts, neurons, and hormone secreting cells (e.g., hepatocytes and islet-like cell aggregates. The outcomes of the studies presented here support the multipotency of SHED and their potential to be used for tissue engineering-based therapies.

  8. Tissue localization of human trefoil factors 1, 2, and 3

    DEFF Research Database (Denmark)

    Madsen, Jens; Nielsen, Ole; Tornøe, Ida

    2007-01-01

    pattern of the three trefoil factors analyzing mRNA from a panel of 20 human tissues by conventional reverse transcriptase (RT) PCR and, in addition, by real-time PCR. These findings were supported by immunohistochemical analysis of paraffin-embedded human tissues using rabbit polyclonal antibodies raised......Trefoil factors (TTFs) are small, compact proteins coexpressed with mucins in the gastrointestinal tract. Three trefoil factors are known in mammals: TFF1, TFF2, and TFF3. They are implicated to play diverse roles in maintenance and repair of the gastrointestinal channel. We compared the expression...... against these factors. TFF1 showed highest expression in the stomach and colon, whereas TFF2 and TFF3 showed highest expression in stomach and colon, respectively. All three TFFs were found in the ducts of pancreas. Whereas TFF2 was found to be restricted to these two tissues, the structurally more...

  9. Tissue distribution of human acetylcholinesterase and butyrylcholinesterase messenger RNA

    Energy Technology Data Exchange (ETDEWEB)

    Jbilo, O.; Barteles, C.F.; Chatonnet, A.; Toutant, J.P.; Lockridge, O.

    1994-12-31

    Tissue distribution of human acetyicholinesterase and butyryicholinesterase messenger RNA. 1 Cholinesterase inhibitors occur naturally in the calabar bean (eserine), green potatoes (solanine), insect-resistant crab apples, the coca plant (cocaine) and snake venom (fasciculin). There are also synthetic cholinesterase inhibitors, for example man-made insecticides. These inhibitors inactivate acetyicholinesterase and butyrylcholinesterase as well as other targets. From a study of the tissue distribution of acetylcholinesterase and butyrylcholinesterase mRNA by Northern blot analysis, we have found the highest levels of butyrylcholinesterase mRNA in the liver and lungs, tissues known as the principal detoxication sites of the human body. These results indicate that butyrylcholinesterase may be a first line of defense against poisons that are eaten or inhaled.

  10. Protective effects of resin sealant and flowable composite coatings against erosive and abrasive wear of dental hard tissues.

    Science.gov (United States)

    Zhao, Xiaoyi; Pan, Jie; Malmstrom, Hans S; Ren, Yan-Fang

    2016-06-01

    To test the effectiveness of sealant and flowable composite coating on eroded enamel, dentin and cementum under erosive/abrasive challenges in vitro. A total of 108 tissue sections (36 each for enamel, dentin and cementum) from third molars were assigned to three groups: Seal & Protect sealant (S&P), Tetric EvoFlow composite (TEF) and control. Erosive/abrasive lesions were created on each specimen by citric acid and brushing with toothpaste. S&P and TEF were applied to the lesions and subjected to erosive/abrasive cycling included 24 cycles of immersion in citric acid (pH 3.6) for 60min, followed by remineralization for 120min and brushing with toothpastes for 600 strokes at 150g. Erosive wear of materials or dental tissues were measured with 3D scanning microscopy and data were analyzed using ANOVA. Treatments with S&P and TEF created a protective material coating of 42.7±17.8μm and 150.8±9.9μm in thickness, respectively. After 24 cycles of erosive/abrasive challenges, tissue losses were -346.9±37.3μm for enamel, -166.5±26.3μm for dentin and -164.7±18.2μm for cementum in untreated controls, as compared to material losses of -24.4±3.3μm for S&P, and -10.8±4.4μm for TEF, respectively. Both S&P and TEF were effective in protecting enamel, dentin and cementum against erosive tooth wear (ppeeling in a third of the specimens. TEF remained intact on all three types of dental tissues at the end of the 24 cycles of erosive/abrasive challenges. A thin coating of flowable composite resin 150μm in thickness may provide long-term protection against erosive/abrasive tooth wear. Resin sealant may provide adequate protection for dental hard tissues in short-term and may require repeated applications if long-term protection is desired. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Infrared absorption of human breast tissues in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Liu Chenglin [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China); Physics Department of Yancheng Teachers' College, Yancheng 224002 (China); Zhang Yuan [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China); Yan Xiaohui [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China); Zhang Xinyi [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China) and Shanghai Research Center of Acupuncture and Meridian, Pudong, Shanghai 201203 (China)]. E-mail: xy-zhang@fudan.edu.cn; Li Chengxiang [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China); Yang Wentao [Cancer Hospital, Medical Center, Fudan University, Shanghai 200032 (China); Shi Daren [Cancer Hospital, Medical Center, Fudan University, Shanghai 200032 (China)

    2006-07-15

    The spectral characteristics of human breast tissues in normal status and during different cancerous stages have been investigated by synchrotron radiation based Fourier transform infrared (SR-FTIR) absorption spectroscopy. Thanks to the excellent synchrotron radiation infrared (IR) source, higher resolving power is achieved in SR-FTIR absorption spectra than in conventional IR absorption measurements. Obvious variations in IR absorption spectrum of breast tissues were found as they change from healthy to diseased, or say in progression to cancer. On the other hand, some specific absorption peaks were found in breast cancer tissues by SR-FTIR spectroscopic methods. These spectral characteristics of breast tissue may help us in early diagnosis of breast cancer.

  12. Comparison of Methods for Analyzing Human Adipose Tissue Macrophage Content

    DEFF Research Database (Denmark)

    Morgan-Bathke, Maria; Harteneck, Debra; Jaeger, Philippa

    2017-01-01

    OBJECTIVE: The relationship between inflammation, obesity, and adverse metabolic conditions is associated with adipose tissue macrophages (ATM). This study compared the measurements of human ATM using flow cytometry, immunohistochemistry (IHC), and real-time polymerase chain reaction (RT-PCR) of ...

  13. Human Bites of the Face with Tissue Losses in Cosmopolitan ...

    African Journals Online (AJOL)

    Dr. Milaki Asuku

    Abstract. A retrospective series of thirty-six cases of human bites to the face with tissue losses requiring reconstruction during a five-year period, January 1999 to December 2003 is presented. The unmarried female in her third decade dominated both as victim and assailant in incidences related to love affairs and love gone ...

  14. Human Bites of the Face with Tissue Losses in Cosmopolitan ...

    African Journals Online (AJOL)

    A retrospective series of thirty-six cases of human bites to the face with tissue losses requiring reconstruction during a five-year period, January 1999 to December 2003 is presented. The unmarried female in her third decade dominated both as victim and assailant in incidences related to love affairs and love gone sour.

  15. Proteome analysis of human colorectal cancer tissue using 2-D ...

    African Journals Online (AJOL)

    Proteome analysis of human colorectal cancer tissue using 2-D DIGE and tandem mass spectrometry for identification of disease-related proteins. ... African Journal of Biotechnology ... The cDNA of the differential protein was transfected into colorectal cancer cells, and the biological behavior of these cells was observed.

  16. Uncovering dental implants using a new thermo-optically powered (TOP) technology with tissue air-cooling.

    Science.gov (United States)

    Romanos, Georgios E; Belikov, Andrey V; Skrypnik, Alexei V; Feldchtein, Felix I; Smirnov, Michael Z; Altshuler, Gregory B

    2015-07-01

    Uncovering implants with lasers, while bloodless, has been associated with a risk of implant and bone overheating. The present study evaluated the effect of using a new generation of high-power diode lasers on the temperature of a dental implant and the surrounding tissues using an in vitro model. The implant temperature was measured at three locations using micro thermocouples. Collateral thermal damage of uncovered soft tissues was evaluated using NTBC stain. Implant temperature rise during and collateral thermal soft-tissue damage following implant uncovering with and without tissue air-cooling was studied using both the classic operational mode and the new thermo-optically powered (TOP) technology. For the classic surgical mode using a cork-initiated tip and constant laser power set at 3.4 W, the maximum temperature rise in the coronal and apical parts of the implant was 23.2 ± 4.1°С and 9.5 ± 1.8°С, respectively, while 1.5 ± 0.5 mm of collateral thermal damage of the soft tissue surrounding the implant model occurred. Using the TOP surgical tip with constant laser power reduced implant overheating by 30%; collateral thermal soft-tissue damage was 0.8 ± 0.2 mm. Using the TOP surgical mode with a tip temperature setting of 800°C and air-cooling reduced the implant temperature rise by more than 300%, and only 0.2 ± 0.1 mm of collateral thermal soft-tissue damage occurred, typical for optimized CO2 laser surgery. Furthermore, use of the new generation diode technology (TOP surgical mode) appeared to reduce the time required for implant uncovering by a factor of two, compared to the standard surgical mode. Use of the new generation diode technology (TOP surgical mode) may significantly reduce overheating of dental implants during uncovering and seems to be safer for the adjacent soft and hard tissues. Use of such diode lasers with air-cooling can radically reduce the rise in implant temperatures (by more than three times

  17. Assessment of permeation of lipoproteins in human carotid tissue

    Science.gov (United States)

    Ghosn, Mohamad G.; Syed, Saba H.; Leba, Michael; Morrisett, Joel D.; Tuchin, Valery V.; Larin, Kirill V.

    2010-02-01

    Cardiovascular disease is among the leading causes of death in the United States. Specifically, atherosclerosis is an increasingly devastating contributor to the tally and has been found to be a byproduct of arterial permeability irregularities in regards to lipoprotein penetration. To further explore arterial physiology and molecular transport, the imaging technique of Optical Coherence Tomography (OCT) was employed. With OCT, the permeation of glucose (MW = 180 Da), low density lipoprotein (LDL; MW = 2.1 × 106 Da), and high density lipoprotein (HDL; MW = 2.5 × 105 Da) in human carotid tissue was studied to determine the effect of different molecular characteristics on permeation in atherosclerotic tissues. The permeability rates calculated from the diffusion of the molecular agents into the abnormal carotid tissue samples is compared to those of normal, healthy tissue. The results show that in the abnormal tissue, the permeation of agents correlate to the size constraints. The larger molecules of LDL diffuse the slowest, while the smallest molecules of glucose diffuse the fastest. However, in normal tissue, LDL permeates at a faster rate than the other two agents, implying the existence of a transport mechanism that facilitates the passage of LDL molecules. These results highlight the capability of OCT as a sensitive and specific imaging technique as well as provide significant information to the understanding of atherosclerosis and its effect on tissue properties.

  18. Expression of matrix metalloproteinases in human breast cancer tissues.

    Science.gov (United States)

    Benson, Chellakkan Selvanesan; Babu, Somasundaram Dinesh; Radhakrishna, Selvi; Selvamurugan, Nagarajan; Ravi Sankar, Bhaskaran

    2013-01-01

    Breast cancer is the most common cancer affecting women in the world today. Matrix metalloproteinases (MMPs) are a family of endopeptidases that can degrade extracellular matrix proteins and promote cell invasion and metastasis. MMPs are differentially expressed and their expressions are often associated with a poor prognosis for patients. The aim of this study is to investigate and compare the expression of MMPs in different grades of human breast cancer tissues with normal breast tissues. We collected 39 breast cancer samples (24 grade II and 15 grade III) along with 16 normal breast tissues from outside the tumor margin during cancer removal surgery. The samples were analysed for the expression of all known MMPs using real-time quantitative PCR. The results indicate that mRNA expressions of MMP-1, -9,-11,-15,-24 and -25 were upregulated in breast cancer tissues when compared to normal breast tissues. But, the mRNA expressions of MMP-10 and MMP-19 were downregulated in cancer tissue. In membrane associated MMPs like MMP-15 and MMP-24 we found a grade dependent increase of their mRNA expression. Our studies demonstrate that MMPs are differentially regulated in breast cancer tissues and they might play various roles in tumor invasion, metastasis and angiogenesis. Thus, MMPs are of immense value to be studied as diagnostic markers and drug target.

  19. Knowledge and attitude of Indian clinical dental students towards the dental treatment of patients with human immunodeficiency virus (HIV)/acquired immune-deficiency syndrome (AIDS).

    Science.gov (United States)

    Oberoi, Sukhvinder Singh; Marya, Charu Mohan; Sharma, Nilima; Mohanty, Vikrant; Marwah, Mohita; Oberoi, Avneet

    2014-12-01

    Oral health care of patients with human immunodeficiency virus (HIV)/acquired immune-deficiency syndrome (AIDS) is a growing area of concern. Information on HIV- and AIDS-related knowledge among dental students provides a crucial foundation for efforts aimed at developing an appropriate dental curriculum on HIV and AIDS. The purpose of this study was to assess the knowledge and attitude of Indian clinical dental students towards the treatment of patients with HIV/AIDS and perceived sources of information regarding HIV-related issues. Data were collected from clinical dental students (third year, fourth year and internship) from three dental institutions in Delhi National Capital Region (NCR). The questions assessed the knowledge and attitude towards treatment of patients with HIV and the perceived source of information related to HIV. The willingness to treat HIV-positive patients among dental students was 67.0%, and 74.20% were confident of treating a patient with HIV/AIDS. The potential problems in rendering treatment to these patients were effect on the attitude of other patients (49.90%) and staff fears (52.50%). The correct knowledge regarding the infection-control practice (barrier technique) was found among only 15.50% of respondents. The respondents had sufficient knowledge regarding the oral manifestations of HIV/AIDS. There was no correlation between the knowledge and attitude score, demonstrating a gap between knowledge and attitude among dental students regarding treatment of HIV-infected patients. Appropriate knowledge has to be delivered through the dental education curriculum, which can instil confidence in students about their ability to manage HIV-positive patients. © 2014 FDI World Dental Federation.

  20. Profiling RNA editing in human tissues: towards the inosinome Atlas

    Science.gov (United States)

    Picardi, Ernesto; Manzari, Caterina; Mastropasqua, Francesca; Aiello, Italia; D’Erchia, Anna Maria; Pesole, Graziano

    2015-01-01

    Adenine to Inosine RNA editing is a widespread co- and post-transcriptional mechanism mediated by ADAR enzymes acting on double stranded RNA. It has a plethora of biological effects, appears to be particularly pervasive in humans with respect to other mammals, and is implicated in a number of diverse human pathologies. Here we present the first human inosinome atlas comprising 3,041,422 A-to-I events identified in six tissues from three healthy individuals. Matched directional total-RNA-Seq and whole genome sequence datasets were generated and analysed within a dedicated computational framework, also capable of detecting hyper-edited reads. Inosinome profiles are tissue specific and edited gene sets consistently show enrichment of genes involved in neurological disorders and cancer. Overall frequency of editing also varies, but is strongly correlated with ADAR expression levels. The inosinome database is available at: http://srv00.ibbe.cnr.it/editing/. PMID:26449202

  1. Zicam-induced damage to mouse and human nasal tissue.

    Directory of Open Access Journals (Sweden)

    Jae H Lim

    Full Text Available Intranasal medications are used to treat various nasal disorders. However, their effects on olfaction remain unknown. Zicam (zinc gluconate; Matrixx Initiatives, Inc, a homeopathic substance marketed to alleviate cold symptoms, has been implicated in olfactory dysfunction. Here, we investigated Zicam and several common intranasal agents for their effects on olfactory function. Zicam was the only substance that showed significant cytotoxicity in both mouse and human nasal tissue. Specifically, Zicam-treated mice had disrupted sensitivity of olfactory sensory neurons to odorant stimulation and were unable to detect novel odorants in behavioral testing. These findings were long-term as no recovery of function was observed after two months. Finally, human nasal explants treated with Zicam displayed significantly elevated extracellular lactate dehydrogenase levels compared to saline-treated controls, suggesting severe necrosis that was confirmed on histology. Our results demonstrate that Zicam use could irreversibly damage mouse and human nasal tissue and may lead to significant smell dysfunction.

  2. Effects of the enamel matrix derivative on the proliferation and odontogenic differentiation of human dental pulp cells.

    Science.gov (United States)

    Wang, Yuanyuan; Zhao, Yuming; Ge, Lihong

    2014-01-01

    The enamel matrix derivative (EMD) has a positive effect on the proliferation of human periodontal ligament cells and the healing of periodontal tissues. The aim of this study was to evaluate the effects of EMD on the proliferation and differentiation of human dental pulp cells (hDPCs) in vitro. hDPCs were isolated from human impacted third molars and cultured in vitro. After treatment with100μg/mL EMD, the proliferation of hDPCs was determined by a cell counting kit 8 (CCK8) assay. After incubation in EMD osteogenic induction medium for 14 days, the osteogenic differentiation of hDPCs was evaluated by alkaline phosphatase (ALP) activity, alizarin staining and the expression of osteogenesis-related genes. The EMD osteogenic induction medium enhanced the proliferation of hDPCs. After osteogenic induction, EMD increased the osteogenic potential of hDPCs, as measured by alkaline phosphatase activity and calcium accumulation; the expression levels of osteogenesis-related genes, such as ALP, DSPP, BMP, and OPN were also upregulated. In addition, the expression levels of odontogenesis-related transcription factors Osterix and Runx2 were upregulated. EMD could enhance the mineralization of hDPSCs upregulated the expression of markers for odontoblast/osteoblast-like cells. Further studies are required to determine if EMD can improve pulp tissue repair and regeneration. Copyright © 2013. Published by Elsevier Ltd.

  3. Slow-freezing versus vitrification for human ovarian tissue cryopreservation.

    Science.gov (United States)

    Klocke, Silke; Bündgen, Nana; Köster, Frank; Eichenlaub-Ritter, Ursula; Griesinger, Georg

    2015-02-01

    Ovarian tissue can be cryopreserved prior to chemotherapy using either the slow-freezing or the vitrification method; however, the data on the equality of the procedures are still conflicting. In this study, a comparison of the cryo-damage of human ovarian tissue induced by either vitrification or slow-freezing was performed. Ovarian tissue from 23 pre-menopausal patients was cryopreserved with either slow-freezing or vitrification. After thawing/warming, the tissue was histologically and immunohistochemically analyzed and cultured in vitro. During tissue culture the estradiol release was assessed. No significant difference was found in the proportion of high-quality follicles after thawing/warming in the slow-freezing and vitrification group, respectively (72.7 versus 66.7 %, p = 0.733). Estradiol secretion by the ovarian tissue was similar between groups during 18 days in vitro culture (area-under-the-curve 5,411 versus 13,102, p = 0.11). Addition of Sphingosine-1-Phosphate or Activin A to the culture medium did not alter estradiol release in both groups. The proportion of Activated Caspase-3 or 'Proliferating-Cell-Nuclear-Antigen' positive follicles at the end of the culture period was similar between slow-freezing and vitrification. Slow-freezing and vitrification result in similar morphological integrity after cryopreservation, a similar estradiol release in culture, and similar rates of follicular proliferation and apoptosis after culture.

  4. Biocompatibility of Accelerated Mineral Trioxide Aggregate on Stem Cells Derived from Human Dental Pulp.

    Science.gov (United States)

    Kulan, Pinar; Karabiyik, Ozge; Kose, Gamze T; Kargul, Betul

    2016-02-01

    The aim of this study was to evaluate the effects of several additives on the setting time and cytotoxicity of accelerated-set mineral trioxide aggregate (MTA) on stem cells of human dental pulp. ProRoot white MTA (WMTA) (Dentsply Tulsa Dental, Johnson City, TN) was mixed with various additives including distilled water, 2.5% disodium hydrogen phosphate (Na2HPO4) (Merck, Darmstadt, Germany), K-Y Jelly (Johnson & Johnson, Markham, ON, Canada), and 5% and 10% calcium chloride (CaCl2) (Merck). The setting times were evaluated using a Vicat apparatus (Alsa Lab, Istanbul, Turkey). Human dental pulp stem cells were isolated and seeded into 48-well plates at 2 × 10(3) cells per well and incubated with MTA samples for 24 hours, 3 days, and 7 days. Cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay. MTA mixed with 10% CaCl2 showed the lowest setting time (P cell viability at all time points (P cell viability of MTA mixed with distilled water, 5% CaCl2, 10% CaCl2, and Na2HPO4 increased significantly through time (P dental pulp stem cells in terms of cell viability. Further in vitro and in vivo investigations are required to prove the clinical applications of MTA mixed with various additives. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  5. Telomere Attrition Occurs during Ex Vivo Expansion of Human Dental Pulp Stem Cells

    Directory of Open Access Journals (Sweden)

    Jaroslav Mokry

    2010-01-01

    Full Text Available We provide a detailed characteristic of stem cells isolated and expanded from the human dental pulp. Dental pulp stem cells express mesenchymal cell markers STRO-1, vimentin, CD29, CD44, CD73, CD90, CD166, and stem cell markers Sox2, nestin, and nucleostemin. They are multipotent as shown by their osteogenic and chondrogenic potential. We measured relative telomere length in 11 dental pulp stem cell lines at different passages by quantitative real-time PCR. Despite their large proliferative capacity, stable viability, phenotype, and genotype over prolonged cultivation, human dental pulp stem cells suffer from progressive telomere shortening over time they replicate in vitro. Relative telomere length (T/S was inversely correlated with cumulative doubling time. Our findings indicate that excessive ex vivo expansion of adult stem cells should be reduced at minimum to avoid detrimental effects on telomere maintenance and measurement of telomere length should become a standard when certificating the status and replicative age of stem cells prior therapeutic applications.

  6. Comparative Analysis of Human Tissue Interactomes Reveals Factors Leading to Tissue-Specific Manifestation of Hereditary Diseases

    OpenAIRE

    Barshir, Ruth; Shwartz, Omer; Smoly, Ilan Y.; Yeger-Lotem, Esti

    2014-01-01

    An open question in human genetics is what underlies the tissue-specific manifestation of hereditary diseases, which are caused by genomic aberrations that are present in cells across the human body. Here we analyzed this phenomenon for over 300 hereditary diseases by using comparative network analysis. We created an extensive resource of protein expression and interactions in 16 main human tissues, by integrating recent data of gene and protein expression across tissues with data of protein-...

  7. Comparative analysis of human tissue interactomes reveals factors leading to tissue-specific manifestation of hereditary diseases.

    OpenAIRE

    Ruth Barshir; Omer Shwartz; Smoly, Ilan Y.; Esti Yeger-Lotem

    2014-01-01

    An open question in human genetics is what underlies the tissue-specific manifestation of hereditary diseases, which are caused by genomic aberrations that are present in cells across the human body. Here we analyzed this phenomenon for over 300 hereditary diseases by using comparative network analysis. We created an extensive resource of protein expression and interactions in 16 main human tissues, by integrating recent data of gene and protein expression across tissues with data of protein-...

  8. Effect of uncontrolled freezing on biological characteristics of human dental pulp stem cells.

    Science.gov (United States)

    Kumar, Ajay; Bhattacharyya, Shalmoli; Rattan, Vidya

    2015-12-01

    Human dental pulp stem cells (hDPSCs) hold great promise as a source of adult stem cells for utilization in regenerative medicine. Successful storage and post thaw recovery of DPSCs without loss of function is a key issue for future clinical application. Most of the cryopreservation methods use controlled rate freezing and vapor phase nitrogen to store stem cells. But these methods are both expensive and laborious. In this study, we isolated DPSCs from a patient undergoing impacted mandibular third molar extraction. We adopted eight different methods of cryopreservation at -80 °C for long term storage of the DPSC aliquots. Various parameters like proliferation, cell death, cell cycle, retention of stemness markers and differentiation potential were studied post cryopreservation period of 1 year. We observed successful recovery of stem cells in every method and a significant difference in proliferation potential and cell death between samples stored by different methods. However, post thaw, all cells retained their stemness markers. All DPSCs stored by different methods were able to differentiate into osteoblast like cells, adipocytes and neural cells. Based on these parameters we concluded that uncontrolled freezing at a temperature of -80 °C is as effective as controlled freezing using ethanol vessels and other cryopreservation methods. To the best of our knowledge, our study provides the first proof of concept that long term storage in uncontrolled freezing of cells at -80 °C in 10 % DMSO does not affect the revival capacity of hDPSCs. This implies that DPSCs may be used successfully for tissue engineering and cell based therapeutics even after long term, uncontrolled cryopreservation.

  9. An Introduction to The Royan Human Ovarian Tissue Bank

    Directory of Open Access Journals (Sweden)

    Abtahi Naeimeh Sadat

    2016-07-01

    Full Text Available From December 2000 until 2010, the researchers at Royan Institute conducted a wide range of investigations on ovarian tissue cryopreservation with the intent to provide fertility pres- ervation to cancer patients that were considered to be candidates for these services. In 2010, Royan Institute established the Royan Human Ovarian Tissue Bank as a subgroup of the Embryology Department. Since its inception, approximately 180 patients between the ages of 747 years have undergone consultations. Ovarian samples were cryopreserved from 47 patients (age: 7-35 years diagnosed with cervical adenocarcinoma (n=9; breast carcinoma (n=7, Ewing’s sarcoma (n=7, opposite side ovarian tumor (n=7, endometrial adenocarci- noma (n=4, malignant colon tumors (n=3, as well as Hodgkin’s lymphoma, major thalas- semia and acute lymphoblastic leukemia (n=1-2 patients for each disease. Additionally, two patients requested ovarian tissue transplantation after completion of their treatments.

  10. Preliminary validation of handheld X-ray fluorescence spectrometry: distinguishing osseous and dental tissue from nonbone material of similar chemical composition.

    Science.gov (United States)

    Zimmerman, Heather A; Schultz, John J; Sigman, Michael E

    2015-03-01

    One of the tasks of a forensic anthropologist is to sort human bone fragments from other materials, which can be difficult when dealing with highly fragmented and taphonomically modified material. The purpose of this research is to develop a method using handheld X-ray fluorescence (HHXRF) spectrometry to distinguish human and nonhuman bone/teeth from nonbone materials of similar chemical composition using multivariate statistical analyses. The sample materials were derived primarily from previous studies: human bone and teeth, nonhuman bone, nonbiological materials, nonbone biological materials, and taphonomically modified materials. The testing included two phases, testing both the reliability of the instrument and the accuracy of the technique. The results indicate that osseous and dental tissue can be distinguished from nonbone material of similar chemical composition with a high degree of accuracy (94%). While it was not possible to discriminate rock apatite and synthetic hydroxyapatite from bone/teeth, this technique successfully discriminated ivory and octocoral. © 2015 American Academy of Forensic Sciences.

  11. Validation of the Maslach Burnout Inventory-Human Services Survey for Estimating Burnout in Dental Students.

    Science.gov (United States)

    Montiel-Company, José María; Subirats-Roig, Cristian; Flores-Martí, Pau; Bellot-Arcís, Carlos; Almerich-Silla, José Manuel

    2016-11-01

    The aim of this study was to examine the validity and reliability of the Maslach Burnout Inventory-Human Services Survey (MBI-HSS) as a tool for assessing the prevalence and level of burnout in dental students in Spanish universities. The survey was adapted from English to Spanish. A sample of 533 dental students from 15 Spanish universities and a control group of 188 medical students self-administered the survey online, using the Google Drive service. The test-retest reliability or reproducibility showed an Intraclass Correlation Coefficient of 0.95. The internal consistency of the survey was 0.922. Testing the construct validity showed two components with an eigenvalue greater than 1.5, which explained 51.2% of the total variance. Factor I (36.6% of the variance) comprised the items that estimated emotional exhaustion and depersonalization. Factor II (14.6% of the variance) contained the items that estimated personal accomplishment. The cut-off point for the existence of burnout achieved a sensitivity of 92.2%, a specificity of 92.1%, and an area under the curve of 0.96. Comparison of the total dental students sample and the control group of medical students showed significantly higher burnout levels for the dental students (50.3% vs. 40.4%). In this study, the MBI-HSS was found to be viable, valid, and reliable for measuring burnout in dental students. Since the study also found that the dental students suffered from high levels of this syndrome, these results suggest the need for preventive burnout control programs.

  12. Autopsy Tissue Program. [Plutonium determination in selected tissues of human cadavers

    Energy Technology Data Exchange (ETDEWEB)

    Fox, T.; Tietjen, G.

    1979-01-01

    The Autopsy Tissue Program was begun in 1960. To date, tissues on 900 or more persons in 7 geographic regions have been collected and analyzed for plutonium content. The tissues generally consist of lung, liver, kidney, lymph, bone, and gonadal tissue for each individual. The original objective of the program was to determine the level of plutonium in human tissues due solely to fall-out from weapons testing. The baseline thus established was to be used to evaluate future changes. From the first, this program was beset with chemical and statistical difficulties. Many factors whose effects were not recognized and not planned for were found later to be important. Privacy and ethical considerations hindered the gathering of adequate data. Since the chemists were looking for amounts of plutonium very close to background, possible contamination was a very real problem. Widely used chemical techniques introduced a host of statistical problems. The difficulties encountered touch on areas common to large data sets, unusual outlier detection methods, minimum detection limits, problems with Aliquot sizes, and time-trends in the data. The conclusions point out areas to which the biologists will have to devote much more careful attention than was believed.

  13. Human Dental Pulp Stem Cells Suppress Alloantigen-induced Immunity by Stimulating T Cells to Release Transforming Growth Factor Beta.

    Science.gov (United States)

    Kwack, Kyu Hwan; Lee, Jung Min; Park, Sang Hyuk; Lee, Hyeon Woo

    2017-01-01

    Human dental pulp stem cells (hDPSCs) are ideal candidates for regenerating damaged dental tissue. To examine the possibility that hDPSCs may be used to regenerate pulp, we tested their in vitro effects on acute allogeneic immune responses. A peripheral blood mononuclear cell (PBMC) proliferation assay and immunoglobulin (Ig) production assay were performed to evaluate the immunosuppressive properties of hDPSCs. The mixed lymphocyte reaction was suppressed by incubation with hDPSCs. Transforming growth factor beta (TGF-β) was the major soluble factor responsible for inhibiting the allogeneic proliferation of PBMCs. The production of IgM and IgG by allogeneic activation of responder B lymphocytes was also completely abrogated by TGF-β released from hDPSCs via interferon gamma in response to activation of the responder T lymphocytes. hDPSCs inhibit acute allogeneic immune responses by their release of TGF-β as a result of allogeneic stimulation of T lymphocytes. This study provides an insight into the potential clinical use of hDPSCs for allogeneic transplantation. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. Comparison of human mesenchymal stem cells derived from bone marrow, synovial fluid, adult dental pulp, and exfoliated deciduous tooth pulp.

    Science.gov (United States)

    Isobe, Y; Koyama, N; Nakao, K; Osawa, K; Ikeno, M; Yamanaka, S; Okubo, Y; Fujimura, K; Bessho, K

    2016-01-01

    Populations of pluripotent stem cells were isolated from bone marrow, synovial fluid, adult dental pulp, and exfoliated deciduous teeth and their multipotentiality properties compared. Osteogenic, chondrogenic, adipogenic, and neurogenic differentiation potentials were examined. Bone marrow mesenchymal stem cells (BMMSCs) and synovial fluid-derived cells (SFCs) showed the highest levels of osteogenesis as expressed by alkaline phosphatase (ALP) activity (0.54±0.094 U/mg protein and 0.57±0.039 U/mg protein, respectively; P=0.60) and by osteocalcin (BGLAP; determined by real-time RT-PCR). SFCs showed the highest levels of chondrogenesis as expressed by ALP activity (1.75±0.097 U/mg protein) and of COL2A1 and COL10A1 by real-time PCR. In terms of adipogenesis, lipid vesicles were observed in the BMMSCs and SFCs. Dental pulp stem cells (DPSCs) and stem cells from human exfoliated deciduous teeth (SHED) exhibited neurogenesis potential, as shown by increases in expression of class III β-tubulin (TUBB3) and microtubule-associated protein 2 (MAP2) on RT-PCR. Variability was found in the differentiation potential corresponding to the tendency of the original tissue to differentiate. It is suggested that the cell type should be selected depending on the regenerative treatment regimen. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  15. Behaviour of human mesenchymal stem cells on chemically synthesized HA-PCL scaffolds for hard tissue regeneration.

    Science.gov (United States)

    D'Antò, Vincenzo; Raucci, Maria Grazia; Guarino, Vincenzo; Martina, Stefano; Valletta, Rosa; Ambrosio, Luigi

    2016-02-01

    Our goal was to characterize the response of human mesenchymal stem cells (hMSCs) to a novel composite scaffold for bone tissue engineering. The hydroxyapatite-polycaprolactone (HA-PCL) composite scaffolds were prepared by a sol-gel method at room temperature and the scaffold morphology was investigated by scanning electron microscopy (SEM)/energy-dispersive spectroscopy (EDS) to validate the synthesis process. The response of two different lines of hMSCs, bone-marrow-derived human mesenchymal stem cells (BMSCs) and dental pulp stem cells (DPSCs) in terms of cell proliferation and differentiation into the osteoblastic phenotype, was evaluated using Alamar blue assay, SEM, histology and alkaline phosphatase activity. Our results indicate that tissue engineering by means of composite HA-PCL scaffolds may represent a new therapeutic strategy to repair craniofacial bone defects. Copyright © 2013 John Wiley & Sons, Ltd.

  16. Spreading, proliferation and differentiation of human dental pulp stem cells on chitosan scaffolds immobilized with RGD or fibronectin.

    Science.gov (United States)

    Asghari Sana, Farzin; Çapkın Yurtsever, Merve; Kaynak Bayrak, Gökçe; Tunçay, Ekin Özge; Kiremitçi, Arlin S; Gümüşderelioğlu, Menemşe

    2017-08-01

    Nowadays, human dental pulp stem cells (hDPSCs) became more attractive for therapeutic purposes because of their high proliferation and differentiation potential. Thus, coupling the desired cellular characteristics of hDPSCs with good biomaterial properties of the chitosan scaffolds provide an interesting approach for tissue engineering applications. On the other hand, scaffold surface modification is also needed to promote stem cell adhesion since chitosan lacks adhesion motifs to support direct cell anchorage. In this study, hDPSCs were isolated from third molars of healthy female individuals (aged 16-25) with enzymatic digestion. For cell culture studies, the chitosan scaffolds which have approximately 9 mm diameter and 2 mm thickness with interconnected structure were prepared by freeze-drying. To support cellular attachment the scaffolds were covalently immobilized with either RGD (arginine-glycine-aspartic acid) or fibronectin (Fn) molecules. Cells were seeded on chitosan scaffolds with or without immobilized RGD and fibronectin. Cell attachment, spreading, adhesion behaviors and proliferation capacity were examined by scanning electron microscopy, immunofluorescence staining and PrestoBlue ® assays, respectively. In addition, differentiation potential of hDPSCs on Fn immobilized chitosan scaffolds was determined with real time reverse transcriptase polymerase chain reaction analysis. The results showed that chitosan scaffolds were not able to support stem cell attachment. hDPSCs on chitosan scaffolds formed spheroids more quickly and the size of spheroids were smaller than on chitosan-RGD while Fn-immobilized chitosan scaffolds strongly supported cellular attachment but not odontogenic differentiation. The results suggest that the Fn-immobilized chitosan scaffolds may serve as good three-dimensional substrates for dental pulp stem cell attachment and proliferation. In the case of dental regeneration, they must be supported by appropriate biosignals to

  17. Expression of the endocannabinoid receptors in human fascial tissue

    Directory of Open Access Journals (Sweden)

    C. Fede

    2016-06-01

    Full Text Available Cannabinoid receptors have been localized in the central and peripheral nervous system as well as on cells of the immune system, but recent studies on animal tissue gave evidence for the presence of cannabinoid receptors in different types of tissues. Their presence was supposed also in myofascial tissue, suggesting that the endocannabinoid system may help resolve myofascial trigger points and relieve symptoms of fibromyalgia. However, until now the expression of CB1 (cannabinoid receptor 1 and CB2 (cannabinoid receptor 2 in fasciae has not yet been established. Small samples of fascia were collected from volunteers patients during orthopedic surgery. For each sample were done a cell isolation, immunohistochemical investigation (CB1 and CB2 antibodies and real time RT-PCR to detect the expression of CB1 and CB2. Both cannabinoid receptors are expressed in human fascia and in human fascial fibroblasts culture cells, although to a lesser extent than the control gene. We can assume that the expression of mRNA and protein of CB1 and CB2 receptors in fascial tissue are concentrated into the fibroblasts. This is the first demonstration that the fibroblasts of the muscular fasciae express CB1 and CB2. The presence of these receptors could help to provide a description of cannabinoid receptors distribution and to better explain the role of fasciae as pain generator and the efficacy of some fascial treatments. Indeed the endocannabinoid receptors of fascial fibroblasts can contribute to modulate the fascial fibrosis and inflammation.

  18. Polarized spectral features of human breast tissues through wavelet ...

    Indian Academy of Sciences (India)

    Polarized spectral features of human breast tissues. 0. 5. 10. 15. 20. 25. 0. 10. 20. 30. 40. 50 patient number cancer normal. 1. 2. 3. 4. 5. 0.95. 0.96. 0.97. 0.98. 0.99. 1 levels. Normalized low pass power cancer normal. (a). (b). Figure 1. (a) Standard deviation of percentage fluctuation (of difference of intensities of parallel and ...

  19. Expression of Matrix Metalloproteinases in Human Breast Cancer Tissues

    OpenAIRE

    Benson, Chellakkan Selvanesan; Babu, Somasundaram Dinesh; Radhakrishna, Selvi; Selvamurugan, Nagarajan; Sankar, Bhaskaran Ravi

    2013-01-01

    BACKGROUND: Breast cancer is the most common cancer affecting women in the world today. Matrix metalloproteinases (MMPs) are a family of endopeptidases that can degrade extracellular matrix proteins and promote cell invasion and metastasis. MMPs are differentially expressed and their expressions are often associated with a poor prognosis for patients. OBJECTIVE: The aim of this study is to investigate and compare the expression of MMPs in different grades of human breast cancer tissues with n...

  20. Sympathetic reflex control of blood flow in human peripheral tissues

    DEFF Research Database (Denmark)

    Henriksen, O

    1991-01-01

    sympathetic vasoconstrictor reflexes are blocked. Blood flow has been measure by the local 133Xe-technique. The results indicate the presence of spinal as well as supraspinal sympathetic vasoconstrictor reflexes to human peripheral tissues. Especially is emphasized the presence of a local sympathetic veno......Sympathetic vasoconstrictor reflexes are essential for the maintenance of arterial blood pressure in upright position. It has been generally believed that supraspinal sympathetic vasoconstrictor reflexes elicited by changes in baroreceptor activity play an important role. Recent studies on human...

  1. Identification and significance of magnetite in human tissues.

    Science.gov (United States)

    Moatamed, F; Johnson, F B

    1986-07-01

    Magnetite or iron oxide has been identified in humans as well as certain animals and bacteria. With the current popularity of magnetic resonance imaging, the presence of these ferromagnetic particles in the tissues may impose biological significance. So far, identification of magnetite in tissue has been mainly based on magnetometry. Hence, a simple technique for direct identification of the magnetic particles in tissues is described. Lung tissues with abundant iron material and particles were digested in 1N sodium hydroxide solution. After rinsing, the sediments were suspended in 95% alcohol and placed on a glass slide located on a strong magnet. The iron-containing particles from the digestion procedure were aligned in a parallel manner along the north-south poles of the magnet and were confirmed to be magnetite by x-ray diffraction. No such effect was observed with hemosiderin-containing granules from the control liver tissues. The results of this experiment show that the "biological magnetite" is distinctly different from hemosiderin and has characteristic properties when subjected to a magnetic field.

  2. FTIR protein secondary structure analysis of human ascending aortic tissues.

    Science.gov (United States)

    Bonnier, Franck; Rubin, Sylvain; Debelle, Laurent; Ventéo, Lydie; Pluot, Michel; Baehrel, Bernard; Manfait, Michel; Sockalingum, Ganesh D

    2008-08-01

    The advent of moderate dilatations in ascending aortas is often accompanied by structural modifications of the main components of the aortic tissue, elastin and collagen. In this study, we have undertaken an approach based on FTIR microscopy coupled to a curve-fitting procedure to analyze secondary structure modifications in these proteins in human normal and pathological aortic tissues. We found that the outcome of the aortic pathology is strongly influenced by these proteins, which are abundant in the media of the aortic wall, and that the advent of an aortic dilatation is generally accompanied by a decrease of parallel beta-sheet structures. Elastin, essentially composed of beta-sheet structures, seems to be directly related to these changes and therefore indicative of the elastic alteration of the aortic wall. Conventional microscopy and confocal fluorescence microscopy were used to compare FTIR microscopy results with the organization of the elastic fibers present in the tissues. This in-vitro study on 6 patients (three normal and three pathologic), suggests that such a spectroscopic marker, specific to aneurismal tissue characterization, could be important information for surgeons who face the dilemma of moderate aortic tissue dilatation of the ascending aortas.

  3. Isolation of Borna Disease Virus from Human Brain Tissue

    Science.gov (United States)

    Nakamura, Yurie; Takahashi, Hirokazu; Shoya, Yuko; Nakaya, Takaaki; Watanabe, Makiko; Tomonaga, Keizo; Iwahashi, Kazuhiko; Ameno, Kiyoshi; Momiyama, Noriko; Taniyama, Hiroyuka; Sata, Tetsutaro; Kurata, Takeshi; de la Torre, Juan Carlos; Ikuta, Kazuyoshi

    2000-01-01

    Serological and molecular epidemiological studies indicate that Borna disease virus (BDV) can infect humans and is possibly associated with certain neuropsychiatric disorders. We examined brain tissue collected at autopsy from four schizophrenic patients and two healthy controls for the presence of BDV markers in 12 different brain regions. BDV RNA and antigen was detected in four brain regions of a BDV-seropositive schizophrenic patient (P2) with a very recent (2 years) onset of disease. BDV markers exhibited a regionally localized distribution. BDV RNA was found in newborn Mongolian gerbils intracranially inoculated with homogenates from BDV-positive brain regions of P2. Human oligodendroglia (OL) cells inoculated with brain homogenates from BDV-positive gerbils allowed propagation and isolation of BDVHuP2br, a human brain-derived BDV. Virus isolation was also possible by transfection of Vero cells with ribonucleoprotein complexes prepared from BDV-positive human and gerbil brain tissues. BDVHuP2br was genetically closely related to but distinct from previously reported human- and animal-derived BDV sequences. PMID:10775596

  4. Streamlined bioreactor-based production of human cartilage tissues.

    Science.gov (United States)

    Tonnarelli, B; Santoro, R; Adelaide Asnaghi, M; Wendt, D

    2016-05-27

    Engineered tissue grafts have been manufactured using methods based predominantly on traditional labour-intensive manual benchtop techniques. These methods impart significant regulatory and economic challenges, hindering the successful translation of engineered tissue products to the clinic. Alternatively, bioreactor-based production systems have the potential to overcome such limitations. In this work, we present an innovative manufacturing approach to engineer cartilage tissue within a single bioreactor system, starting from freshly isolated human primary chondrocytes, through the generation of cartilaginous tissue grafts. The limited number of primary chondrocytes that can be isolated from a small clinically-sized cartilage biopsy could be seeded and extensively expanded directly within a 3D scaffold in our perfusion bioreactor (5.4 ± 0.9 doublings in 2 weeks), bypassing conventional 2D expansion in flasks. Chondrocytes expanded in 3D scaffolds better maintained a chondrogenic phenotype than chondrocytes expanded on plastic flasks (collagen type II mRNA, 18-fold; Sox-9, 11-fold). After this "3D expansion" phase, bioreactor culture conditions were changed to subsequently support chondrogenic differentiation for two weeks. Engineered tissues based on 3D-expanded chondrocytes were more cartilaginous than tissues generated from chondrocytes previously expanded in flasks. We then demonstrated that this streamlined bioreactor-based process could be adapted to effectively generate up-scaled cartilage grafts in a size with clinical relevance (50 mm diameter). Streamlined and robust tissue engineering processes, as the one described here, may be key for the future manufacturing of grafts for clinical applications, as they facilitate the establishment of compact and closed bioreactor-based production systems, with minimal automation requirements, lower operating costs, and increased compliance to regulatory guidelines.

  5. The Role of ORAI1 in the Odontogenic Differentiation of Human Dental Pulp Stem Cells.

    Science.gov (United States)

    Sohn, S; Park, Y; Srikanth, S; Arai, A; Song, M; Yu, B; Shin, K-H; Kang, M K; Wang, C; Gwack, Y; Park, N-H; Kim, R H

    2015-11-01

    Pulp capping, or placing dental materials directly onto the vital pulp tissues of affected teeth, is a dental procedure that aims to regenerate reparative dentin. Several pulp capping materials are clinically being used, and calcium ion (Ca(2+)) released from these materials is known to mediate reparative dentin formation. ORAI1 is an essential pore subunit of store-operated Ca(2+) entry (SOCE), which is a major Ca(2+) influx pathway in most nonexcitable cells. Here, we evaluated the role of ORAI1 in mediating the odontogenic differentiation and mineralization of dental pulp stem cells (DPSCs). During the odontogenic differentiation of DPSCs, the expression of ORAI1 increased in a time-dependent manner. DPSCs knocked down with ORAI1 shRNA (DPSC/ORAI1sh) or overexpressed with dominant negative mutant ORAI1(E106Q) (DPSC/E106Q) exhibited the inhibition of Ca(2+) influx and suppression of odontogenic differentiation and mineralization as demonstrated by alkaline phosphatase (ALP) activity/staining as well as alizarin red S staining when compared with DPSCs of their respective control groups (DPSC/CTLsh and DPSC/CTL). The gene expression for odontogenic differentiation markers such as osteocalcin, bone sialoprotein, and dentin matrix protein 1 (DMP1) was also suppressed. When DPSC/CTL or DPSC/E106Q cells were subcutaneously transplanted into nude mice, DPSC/CTL cells induced mineralized tissue formation with significant increases in ALP and DMP1 staining in vivo, whereas DPSC/E106Q cells did not. Collectively, our data showed that ORAI1 plays critical roles in the odontogenic differentiation and mineralization of DPSCs by regulating Ca(2+) influx and that ORAI1 may be a therapeutic target to enhance reparative dentin formation. © International & American Associations for Dental Research 2015.

  6. Expression cartography of human tissues using self organizing maps.

    Science.gov (United States)

    Wirth, Henry; Löffler, Markus; von Bergen, Martin; Binder, Hans

    2011-07-27

    Parallel high-throughput microarray and sequencing experiments produce vast quantities of multidimensional data which must be arranged and analyzed in a concerted way. One approach to addressing this challenge is the machine learning technique known as self organizing maps (SOMs). SOMs enable a parallel sample- and gene-centered view of genomic data combined with strong visualization and second-level analysis capabilities. The paper aims at bridging the gap between the potency of SOM-machine learning to reduce dimension of high-dimensional data on one hand and practical applications with special emphasis on gene expression analysis on the other hand. The method was applied to generate a SOM characterizing the whole genome expression profiles of 67 healthy human tissues selected from ten tissue categories (adipose, endocrine, homeostasis, digestion, exocrine, epithelium, sexual reproduction, muscle, immune system and nervous tissues). SOM mapping reduces the dimension of expression data from ten of thousands of genes to a few thousand metagenes, each representing a minicluster of co-regulated single genes. Tissue-specific and common properties shared between groups of tissues emerge as a handful of localized spots in the tissue maps collecting groups of co-regulated and co-expressed metagenes. The functional context of the spots was discovered using overrepresentation analysis with respect to pre-defined gene sets of known functional impact. We found that tissue related spots typically contain enriched populations of genes related to specific molecular processes in the respective tissue. Analysis techniques normally used at the gene-level such as two-way hierarchical clustering are better represented and provide better signal-to-noise ratios if applied to the metagenes. Metagene-based clustering analyses aggregate the tissues broadly into three clusters containing nervous, immune system and the remaining tissues. The SOM technique provides a more intuitive and

  7. Effects of VEGF and FGF2 on the revascularization of severed human dental pulps.

    Science.gov (United States)

    Mullane, E M; Dong, Z; Sedgley, C M; Hu, J C-C; Botero, T M; Holland, G R; Nör, J E

    2008-12-01

    The long-term outcome of replanted avulsed permanent teeth is frequently compromised by lack of revascularization, resulting in pulp necrosis. The purpose of this study was to evaluate the effects of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF-2) on the revascularization of severed human dental pulps. Tooth slices were prepared from non-carious human molars and treated with 0-50 ng/mL rhVEGF(165) or rhFGF-2 for 7 days in vitro. Both angiogenic factors enhanced pulp microvessel density compared with untreated controls (p dental pulps and suggest that topical application of an angiogenic factor prior to replantation might be beneficial for the treatment of avulsed teeth.

  8. A feasibility of useful cell-based therapy by bone regeneration with deciduous tooth stem cells, dental pulp stem cells, or bone-marrow-derived mesenchymal stem cells for clinical study using tissue engineering technology.

    Science.gov (United States)

    Yamada, Yoichi; Nakamura, Sayaka; Ito, Kenji; Sugito, Takayuki; Yoshimi, Ryoko; Nagasaka, Tetsuro; Ueda, Minoru

    2010-06-01

    This study investigated the effect of bone regeneration with dental pulp stem cells (DPSCs), deciduous tooth stem cells (DTSCs), or bone-marrow-derived mesenchymal stem cells (BMMSCs) for clinical study on hydroxyapatite-coated osseointegrated dental implants, using tissue engineering technology. In vitro, human DPSCs and DTSCs expressed STRO-1, CD13, CD29, CD 44, CD73, and osteogenic marker genes such as alkaline phosphatase, Runx2, and osteocalcin. In vivo, prepared bone defect model was implanted using graft materials as follows: platelet-rich plasma (PRP), PRP and canine BMMSCs (cBMMSCs), PRP and canine DPSCs (cDPSCs), PRP and puppy DTSCs (pDTSCs), and control (defect only). After 8 weeks, the dental implants were installed, and 16 weeks later the sections were evaluated histologically and histometrically. The cBMMSCs/PRP, cDPSCs/PRP, and pDTSCs/PRP groups had well-formed mature bone and neovascularization. Histometrically, the bone-implant contact was significantly different between the cBMMSCs/PRP, cDPSCs/PRP, pDTSCs/PRP groups, and the control and PRP groups (p < 0.01). These results demonstrated that these stem cells with PRP have the ability to form bone, and this bone formation activity might be useful for osseointegrated hydroxyapatite-coated dental implants with good levels of bone-implant contact.

  9. Application of the Dental Hygiene Human Needs Conceptual Model and the Oral Health-Related Quality of Life Model to the dental hygiene curriculum in Japan.

    Science.gov (United States)

    Sato, Y; Saito, A; Nakamura-Miura, A; Kato, E; Cathcart, G

    2007-08-01

    This paper reports the incorporation of the Dental Hygiene Human Needs Conceptual Model (DHHN) and the Oral Health-Related Quality of Life Model (OHRQL) into a dental hygiene curriculum in Japan. A simulated patient practice was offered to 67 dental hygiene students. In the practice activity, all students were introduced to the use of an OHRQL assessment tool. A DHHN assessment tool was utilized additionally only by the experimental student group. The statistical analysis of the post-practice survey showed that the OHRQL instrument was more helpful in assessment and problem identification than the DHHN instrument. By contrast, text-based analysis of dental hygiene diagnostic statements showed that the experimental group identified more domains of patients' human needs deficits than the control group. This suggested the possibility that the DHHN model helped them to see patients from broader perspectives. However, it was difficult for students to design care plans attending to the domains of the models. Also, in considerations to the cultural issues, the validity and equivalence of the Japanese versions of both models should be further investigated. Within the limitation of the present study, the results suggested that incorporation of the combination of the DHHN and OHRQL models can be useful in a dental hygiene curriculum, as each tool helps students expand the perspective from which they view client. Further improvements in learning strategies should facilitate the effective utilization of these models.

  10. The Effect of Glass Ionomer and Adhesive Cements on Substance P Expression in Human Dental Pulp

    OpenAIRE

    Caviedes Bucheli, Javier; Ariza García, Germán; Camelo, Patricia; Mejía, Mónica; Ojeda, Karyn; Azuero Holguin, María Mercedes; Abad Coronel, Dunia; Munoz, Hugo-Roberto

    2013-01-01

    Objectives: The purpose of this study was to quantify the effect of glass ionomer and adhesive cements on SP expression in healthy human dental pulp. Study Design: Forty pulp samples were obtained from healthy premolars where extraction was indicated for orthodontic reasons. In thirty of these premolars a Class V cavity preparation was performed and teeth were equally divided in three groups: Experimental Group I: Glass Ionomer cement was placed in the cavity. Experimental Group II: Adhesive ...

  11. Effect of Biodentine™ on the proliferation, migration and adhesion of human dental pulp stem cells.

    Science.gov (United States)

    Luo, Zhirong; Li, Dongmei; Kohli, Meetu R; Yu, Qing; Kim, Syngcuk; He, Wen-Xi

    2014-04-01

    To investigate the proliferative, migratory and adhesion effect of Biodentine™, a new tricalcium silicate cement formulation, on the human dental pulp stem cells (hDPSCs). The cell cultures of hDPSCs obtained from impacted third molars were treated with Biodentine™ extract at four different concentrations: Biodentine™ 0.02mg/ml (BD 0.02), Biodentine™ 0.2mg/ml (BD 0.2), Biodentine™ 2mg/ml (BD 2) and Biodentine™ 20mg/ml (BD 20). Human dental pulp stem cells proliferation was evaluated by MTT (3-(4,5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide) and BrdU (5-bromo-2'-deoxyuridine) viability analysis at different times. Migration was investigated by microphotographs of wound healing and transwell migration assays. Adhesion assay was performed as well in presence of BD 0.2, BD 2 and blank control, while qRT-PCR (quantitative real-time reverse-transcriptase polymerase chain) was used for further analysis of the mRNA expression of chemokine and adhesion molecules in hDPSCs. Biodentine™ significantly increased proliferation of stem cells at BD 0.2 and BD 2 concentrations while decreased significantly at higher concentration of BD 20. BD 0.2 concentration had a statistically significant increased migration and adhesion abilities. In addition, qRT-PCR results showed that BD 0.2 could have effect on the mRNA expression of chemokines and adhesion molecules in human dental pulp stem cells. The data imply that Biodentine™ is a bioactive and biocompatible material capable of enhancing hDPSCs proliferation, migration and adhesion abilities. Biodentine™ when placed in direct contact with the pulp during pulp exposure can positively influence healing by enhancing the proliferation, migration and adhesion of human dental pulp stem cells. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Microscopic evaluation of the human dental pulp after full crown cementation with resin cement

    OpenAIRE

    Santiago, Luiz C.; Pegoraro, Luiz F.; Consolaro, Alberto; Valle, Accácio L. do; Bonfante, Gerson

    2010-01-01

    This study evaluated microscopically the dental pulp reactions in human premolars prepared for metaloceramic crowns cemented with different luting agents and also measured the remaining dentin thickness (RDT) of the prepared teeth. Twenty-five teeth were selected from patients that needed exodontia for orthodontic reasons and were randomly divided in three groups: group 1- five teeth were not prepared to serve as a positive control group; groups - 2, and 3 the teeth were prepared for metaloce...

  13. Direct evidence of milk consumption from ancient human dental calculus

    DEFF Research Database (Denmark)

    Warinner, C.; Hendy, J.; Speller, C.

    2014-01-01

    Milk is a major food of global economic importance, and its consumption is regarded as a classic example of gene-culture evolution. Humans have exploited animal milk as a food resource for at least 8500 years, but the origins, spread, and scale of dairying remain poorly understood. Indirect lines...... of evidence, such as lipid isotopic ratios of pottery residues, faunal mortality profiles, and lactase persistence allele frequencies, provide a partial picture of this process; however, in order to understand how, where, and when humans consumed milk products, it is necessary to link evidence of consumption...

  14. The Effects of Platelet-Derived Growth Factor-BB on Human Dental Pulp Stem Cells Mediated Dentin-Pulp Complex Regeneration.

    Science.gov (United States)

    Zhang, Maolin; Jiang, Fei; Zhang, Xiaochen; Wang, Shaoyi; Jin, Yuqin; Zhang, Wenjie; Jiang, Xinquan

    2017-12-01

    Dentin-pulp complex regeneration is a promising alternative treatment for the irreversible pulpitis caused by tooth trauma or dental caries. This process mainly relies on the recruitment of endogenous or the transplanted dental pulp stem cells (DPSCs) to guide dentin-pulp tissue formation. Platelet-derived growth factor (PDGF), a well-known potent mitogenic, angiogenic, and chemoattractive agent, has been widely used in tissue regeneration. However, the mechanisms underlying the therapeutic effects of PDGF on dentin-pulp complex regeneration are still unclear. In this study, we tested the effect of PDGF-BB on dentin-pulp tissue regeneration by establishing PDGF-BB gene-modified human dental pulp stem cells (hDPSCs) using a lentivirus. Our results showed that PDGF-BB can significantly enhance hDPSC proliferation and odontoblastic differentiation. Furthermore, PDGF-BB and vascular endothelial growth factor (VEGF) secreted by hDPSCs enhanced angiogenesis. The chemoattractive effect of PDGF-BB on hDPSCs was also confirmed using a Transwell chemotactic migration model. We further determined that PDGF-BB facilitates hDPSCs migration via the activation of the phosphatidylinositol 3 kinase (PI3K)/Akt signaling pathway. In vivo, CM-DiI-labeled hDPSCs were injected subcutaneously into mice, and our results showed that more labeled cells were recruited to the sites implanted with calcium phosphate cement scaffolds containing PDGF-BB gene-modified hDPSCs. Finally, the tissue-engineered complexes were implanted subcutaneously in mice for 12 weeks, the Lenti-PDGF group generated more dentin-like mineralized tissue which showed positive staining for the DSPP protein, similar to tooth dentin tissue, and was surrounded by highly vascularized dental pulp-like connective tissue. Taken together, our data demonstrated that the PDGF-BB possesses a powerful function in prompting stem cell-based dentin-pulp tissue regeneration. Stem Cells Translational Medicine 2017;6:2126-2134. © 2017

  15. Maintenance of fetal human pancreatic beta cells in tissue culture.

    Science.gov (United States)

    McEvoy, R C; Thomas, N M; Bowers, C; Ginsberg-Fellner, F

    1986-01-01

    Large quantities of viable human islet tissue (beta cells) are required for transplant and for investigations of the autoimmune basis of Type I diabetes. Fetal pancreas offers a potential advantage over other possible sources of beta cells in that it retains some capacity for growth in vitro. We have cultured a total of 45 human pancreata from fetuses of gestational ages from 18 to 23 weeks. Each pancreas was obtained within minutes after delivery and usually cultured within 30 minutes. Pancreata were dispersed and cultured for up to 32 days. Maintenance and growth of the beta cells was assessed by the content of insulin in extracts of cultured tissue. As has been reported by others, fetal human beta cells survived in vitro for over 4 weeks. In three experiments in which a direct comparison was made, collagenase digestion of the fetal pancreas resulted in a significantly greater loss of insulin content compared to minced tissue cultured without digestion. Storage of three pancreata in medium overnight at 4 degrees C significantly reduced the insulin content of the pancreas compared to pancreata cultured immediately. During culture, the majority of the beta cells (based on insulin content) were found in small, macroscopic clumps attached to the surface of the culture dish, and surrounded by a nearly confluent monolayer of fibroblastoid cells. There was a marked decrease in the insulin content of the tissue during culture, most of it (to less than 25% of the original) occurring over the first 4-6 days of culture.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. PVA matches human liver in needle-tissue interaction.

    Science.gov (United States)

    de Jong, Tonke L; Pluymen, Loes H; van Gerwen, Dennis J; Kleinrensink, Gert-Jan; Dankelman, Jenny; van den Dobbelsteen, John J

    2017-05-01

    Medical phantoms can be used to study needle-tissue interaction and to train medical residents. The purpose of this research is to study the suitability of polyvinyl alcohol (PVA) as a liver tissue mimicking material in terms of needle-tissue interaction. Insertions into ex-vivo human livers were used for reference. Six PVA samples were created by varying the mass percentage of PVA to water (4m% and 7m%) and the number of freeze-thaw cycles (1, 2 and 3 cycles, 16hours of freezing at -19°C, 8hours of thawing). The inner needle of an 18 Gauge trocar needle with triangular tip was inserted 13 times into each of the samples, using an insertion velocity of 5 mm/s. In addition, 39 insertions were performed in two ex-vivo human livers. Axial forces on the needle were captured during insertion and retraction and characterized by friction along the needle shaft, peak forces, and number of peak forces per unit length. The concentration of PVA and the number of freeze-thaw cycles both influenced the mechanical interaction between needle and specimen. Insertions into 4m% PVA phantoms with 2 freeze-thaw cycles were comparable to human liver in terms of estimated friction along the needle shaft and the number of peak forces.