WorldWideScience
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Autoradiographic study of 3H-proline incorporation by rat periodontal ligament, gingival connective tissue and dental pulp  

International Nuclear Information System (INIS)

The rates of 3H-proline incorporation by the rat periodontal ligament, the gingival connective tissue and the dental pulp were studied by autoradiography. The rate of 3H-proline incorporation by the periodontal ligament was 2.8 times higher than by the gingival connective tissue and 5 times higher than by the dental pulp. These differences were significant (p3H-proline incorporation by the periodontal ligament was significantly different (p3H-proline incorporation. The ratio of the rates of 3H-proline incorporation by the three tissues did not correlate with the ratio of the cellular densities in the same three tissues. (author)

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Cell survival within pulp and periodontal constructs.  

Science.gov (United States)

The purpose of this study was to measure cell survival and degradation within tissue-engineered dental constructs. Dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PLSCs) were seeded on three types of tissue engineering scaffolds: a synthetic open-cell D,D-L,L-polylactic acid (polymer) scaffold, a bovine collagen scaffold (collagen), and a calcium phosphate bioceramic (calcium phosphate) scaffold. The dental pulp and periodontal constructs (n = 144) were maintained in cell culture for between 3 and 14 days. The cell survival and degradation within the constructs were measured using histologic criteria. The DPSC and PLSC survival was optimal in the polymer and collagen constructs but not the calcium phosphate constructs, especially over longer time periods. These in vitro results suggest that both the polymer and collagen scaffolds and the DPSCs and PLSCs can be combined to create pulp and periodontal constructs for use in future regenerative dental treatments. PMID:19084127

Gebhardt, Matthew; Murray, Peter E; Namerow, Kenneth N; Kuttler, Sergio; Garcia-Godoy, Franklin

2009-01-01

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The efficiency of the in vitro osteo/dentinogenic differentiation of human dental pulp cells, periodontal ligament cells and gingival fibroblasts.  

Science.gov (United States)

Although the primary cell cultures from dental pulp and other oral tissue are frequently used to study osteogenic potential and stem cell responses, few systematic and comparative studies on stemness for the dentinogenic differentiation of these cells have been conducted. In the present study, to investigate the stemness of oral primary cells during extended culture, human adult dental pulp cells (hDPCs), periodontal ligament stem cells (hPDLSCs) and gingival fibroblasts (hGFs) were obtained and cultured from pulp tissue, periodontal ligaments, and marginal and attached gingival tissue of extracted third molars, respectively. As shown by fluorescence-activated cell sorting analysis and immunophenotyping, the mesenchymal stem cell markers, CD44, CD73, CD90, CD146 and CD166, were highly expressed in early passage hDPCs, hPDLSCs and hGFs. However, when the cells were treated with osteogenic additives, mineralization markedly increased in the hDPCs and hPDLSCs, but not in the hGFs. Moreover, the expression of dentinogenic markers, such as dentin sialophosphoprotein and dentin matrix protein-1, appeared to decrease during extended culture past passage number 8 of the hDPCs and hPDLSCs. These data suggest that hDPCs and hPDLSCs may have differentiation potential during the early passages, and that their progenitor potential is diminished during extended culture. The hGFs did not show differentiation capability during culture, even though they contained general mesenchymal stem cell surface proteins. The transcriptional expression of dentinogenic markers in hDPCs was not affected by co-culture with hPDLSCs and/or hGFs. PMID:25355399

Choi, Jung-Kwon; Hwang, Hyo-In; Jang, Young-Joo

2015-01-01

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Periodontal Ligament Stem Cell-Mediated Treatment for Periodontitis in Miniature Swine  

OpenAIRE

Periodontitis is a periodontal tissue infectious disease and the most common cause for tooth loss in adults. It has been linked to many systemic disorders, such as coronary artery disease, stroke, and diabetes. At present, there is no ideal therapeutic approach to cure periodontitis and achieve optimal periodontal tissue regeneration. In this study, we explored the potential of using autologous periodontal ligament stem cells (PDLSCs) to treat periodontal defects in a porcine model of periodo...

Liu, Yi; Zheng, Ying; Ding, Gang; Fang, Dianji; Zhang, Chunmei; Bartold, Peter Mark; Gronthos, Stan; Shi, Songtao; Wang, Songlin

2008-01-01

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Periodontal ligament stem cells: an update and perspectives.  

Science.gov (United States)

Chronic periodontitis is a serious infectious and inflammatory oral disease of humans worldwide. Conventional treatment modalities are effective for controlling periodontal disease. However, the regeneration of damaged periodontal tissues remains a major challenge in clinical practice due to the complex structure of the periodontium. Stem cell-based regenerative approaches combined with the usage of emerging biomaterials are entering a new era in periodontal regeneration. The present review updates the current knowledge of periodontal ligament stem cell-based approaches for periodontal regeneration, and elaborates on the potentials for clinical application. PMID:24610628

Chamila Prageeth Pandula, P K; Samaranayake, L P; Jin, L J; Zhang, Chengfei

2014-05-01

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Role of periodontal ligament fibroblasts in osteoclastogenesis: a review.  

Science.gov (United States)

During the last decade it has become clear that periodontal ligament fibroblasts may contribute to the in vitro differentiation of osteoclasts. We surveyed the current findings regarding their osteoclastogenesis potential. Periodontal ligament fibroblasts have the capacity to select and attract osteoclast precursors and subsequently to retract and enable migration of osteoclast precursors to the bone surface. There, fusion of precursors takes place, giving rise to osteoclasts. The RANKL-RANK-osteoprotegerin (OPG) axis is considered crucial in this process. Periodontal ligament fibroblasts produce primarily OPG, an osteoclastogenesis-inhibitory molecule. However, they may be influenced in vivo by direct or indirect interactions with bacteria or by mechanical loading. Incubation of periodontal ligament fibroblasts with bacteria or bacterial components causes an increased expression of RANKL and other osteoclastogenesis-stimulating molecules, such as tumor necrosis factor-? and macrophage-colony stimulating factor. Similar results are observed after the application of mechanical loading to these fibroblasts. Periodontal ligament fibroblasts may be considered to play an important role in the remodelling of alveolar bone. In vitro experiments have demonstrated that periodontal ligament fibroblasts adapt to bacterial and mechanical stimuli by synthesizing higher levels of osteoclastogenesis-stimulating molecules. Therefore, they probably contribute to the enhanced osteoclast formation observed during periodontitis and to orthodontic tooth movement. PMID:24862732

Sokos, D; Everts, V; de Vries, T J

2014-05-24

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Decellularized periodontal ligament cell sheets with recellularization potential.  

Science.gov (United States)

The periodontal ligament is the key tissue facilitating periodontal regeneration. This study aimed to fabricate decellularized human periodontal ligament cell sheets for subsequent periodontal tissue engineering applications. The decellularization protocol involved the transfer of intact human periodontal ligament cell sheets onto melt electrospun polycaprolactone membranes and subsequent bi-directional perfusion with NH4OH/Triton X-100 and DNase solutions. The protocol was shown to remove 92% of DNA content. The structural integrity of the decellularized cell sheets was confirmed by a collagen quantification assay, immunostaining of human collagen type I and fibronectin, and scanning electron microscopy. ELISA was used to demonstrate the presence of residual basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), and hepatocyte growth factor (HGF) in the decellularized cell sheet constructs. The decellularized cell sheets were shown to have the ability to support recellularization by allogenic human periodontal ligament cells. This study describes the fabrication of decellularized periodontal ligament cell sheets that retain an intact extracellular matrix and resident growth factors and can support repopulation by allogenic cells. The decellularized hPDL cell sheet concept has the potential to be utilized in future "off-the-shelf" periodontal tissue engineering strategies. PMID:25270757

Farag, A; Vaquette, C; Theodoropoulos, C; Hamlet, S M; Hutmacher, D W; Ivanovski, S

2014-12-01

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Immunomodulatory properties of human periodontal ligament stem cells.  

Science.gov (United States)

Tissue engineering utilizing periodontal ligament stem cells (PDLSCs) has recently been proposed for the development of new periodontal regenerative therapies. Although the use of autologous PDLSC transplantation eliminates the potential of a significant host immune response against the donor cells, it is often difficult to generate enough PDLSCs from one donor source due to the variation of stem cell potential between donors and disease state of each patient. In this study, we examined the immunomodulatory properties of PDLSCs as candidates for new allogeneic stem cell-based therapies. Human PDLSCs displayed cell surface marker characteristics and differentiation potential similar to bone marrow stromal stem cells (BMSSCs) and dental pulp stem cells (DPSCs). PDLSCs, BMSSCs, and DPSCs inhibited peripheral blood mononuclear cell (PBMNC) proliferation stimulated with mitogen or in an allogeneic mixed lymphocyte reaction (MLR). Interestingly, gingival fibroblasts (GFs) also suppressed allogeneic PBMNC proliferation under both assay conditions. PDLSCs, BMSSCs, DPSCs, and GFs exhibited non-cell contact dependent suppression of PBMNC proliferation in co-cultures using transwells. Furthermore, conditioned media (CM) derived from each cell type pretreated with IFN-gamma partially suppressed PBMNC proliferation when compared to CMs without IFN-gamma stimulation. In all of these mesenchymal cell types cultured with activated PBMNCs, the expression of TGF-beta1, hepatocyte growth factor (HGF) and indoleamine 2, 3-dioxygenase (IDO) was upregulated while IDO expression was upregulated following stimulation with IFN-gamma. These results suggest that PDLSCs, BMSSCs, DPSCs, and GFs possess immunosuppressive properties mediated, in part, by soluble factors, produced by activated PBMNCs. J. Cell. Physiol. 219: 667-676, 2009. (c) 2009 Wiley-Liss, Inc. PMID:19160415

Wada, Naohisa; Menicanin, Danijela; Shi, Songtao; Bartold, P Mark; Gronthos, Stan

2009-06-01

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Progenitor cell populations in the periodontal ligament of mice  

International Nuclear Information System (INIS)

Stem cells in a variety of renewal tissues exhibit a slow rate of cell proliferation. The periodontal ligament of mouse molars was examined for the presence of slowly cycling progenitor cells to provide evidence for the existence of stem cells in this tissue. A pulse injection of 3H-thymidine was administered and mice were sacrificed between 1 hour and 14 days after injection. Analysis of radioautographs using percentage of labeled cells and grain counts demonstrated that a population of label-retaining cells within 10 micron of blood vessels traversed the cell cycle more slowly than proliferating cells located greater than 10 micron from blood vessels. These data suggest that there is a slowly dividing population of progenitor cells in paravascular sites in mouse molar periodontal ligament which may be stem cells

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Trial analysis of swine's periodontal ligament with Bragg grating sensors  

Science.gov (United States)

In this work it is reported the measurement of the differential strain between the dental and bone tissues under effect of an applied load. Slices of swine mandible, containing the premolar tooth, are cut and measured in fresh condition. The strain is measured using fibre Bragg grating sensors glued to both tissues. In the measured range the results show a linear behaviour and confirm the importance of the periodontal ligament in the load transfer mechanism.

Menegotto, G. F.; Grabarski, L.; Kalinowski, H. J.; Simões, J. A.

2009-10-01

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Fibroblast cell proliferation in the mouse molar periodontal ligament.  

OpenAIRE

Cytogenesis of the developing molar periodontal ligament was studied by determining labelling indices in 4 groups of young mice. Autoradiographs were made using paraffin sections of demineralised specimens from 10 days, 12 days, 16 days and 20 days old mice allowed to survive a varying period (1--96 hours) after the administration of [3H]thymidine. Labelled fibroblasts in number per unit area were counted over three different zones (apical, middle and cervical) of the sections and labelling i...

Perera, K. A.; Tonge, C. H.

1981-01-01

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Mesenchymal stem cells isolated from human periodontal ligament  

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Full Text Available Mesenchymal stem cells (MSCs were isolated from human periodontal ligament (hPDL-MSCs and characterized by their morphology, clonogenic efficiency, proliferation and differentiation capabilities. hPDL-MSCs, derived from normal impacted third molars, possessed all of the properties of MSC, including clonogenic ability, high proliferation rate and multi-lineage (osteogenic, chondrogenic, adipogenic, myogenic differentiation potential. Moreover, hPDL-MSCs expressed a typical MSC epitope profile, being positive for mesenchymal cell markers (CD44H, CD90, CD105, CD73, CD29, Stro-1, fibronectin, vimentin, ?-SMA, and negative for hematopoietic stem cell markers (CD34, CD11b, CD45, Glycophorin-CD235a. Additionally, hPDL-MSCs, as primitive and highly multipotent cells, showed high expression of embryonic markers (Nanog, Sox2, SSEA4. The data obtained provided yet further proof that cells with mesenchymal properties can be obtained from periodontal ligament tissue. Although these cells should be further investigated to determine their clinical significance, hPDL-MSCs are believed to provide a renewable and promising cell source for new therapeutic strategies in the treatment of periodontal defects. [Projekat Ministarstva nauke Republike Srbije, br. 175062 i br. III 41011

Mileti? Maja

2014-01-01

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Periodontal Ligament Cell Sheet Engineering: A new Possible Strategy to Promote Periodontal Regeneration  

OpenAIRE

Introduction: Osseointegration represents a direct structural and functional connection between ordered, living bone and the surface of a load-carrying implant without the periodontium. As a result, im-plant fracture or aggressive bone loss sometime occurs because the patient cannot feel the mechanical overloads exerted on the implant. Until now, no available method has been used to solve this problem.The hypothesis: Periodontal ligament (PDL) cells are a desirable cell population capable of ...

Dong-sheng Zhang; Sheng-yun Huang

2010-01-01

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Capturing the Regenerative Potential of Periodontal Ligament Fibroblasts  

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Full Text Available The cell population within the periodontal ligament (PDL tissue is remarkably heterogeneous1. Fibroblasts, a mixed population of cells, are the main cellular component of the PDL and the cell type most often studied for periodontal regeneration. Osteoblasts and osteoclasts are found on the bone side, while fibroblasts, macrophages, undifferentiated adult/mesenchymal stem cells, neural elements, and endothelial cells are found throughout the PDL. Epithelial rests of Malassez cells and cementoblasts are focused near the root surface. PDL tissue also includes loose connective tissue between dense fiber bundles that contain branches of the periodontal blood vessels and nerves2. The complexity of the PDL tissue, with its various cell types and cell progenitor components, explains the challenges involved in therapies to restore tissue following periodontal disease. Cementoblasts, osteoblasts, and endothelial cells must migrate, differentiate, and coordinately interact with a variety of soluble mediators to regenerate the periodontium3. Stem cells located in the PDL tissue are key contributors to this process4. Stem cells in the PDL are important not only for formation and maintenance of the tissue but also for repair, remodeling, and regeneration of adjacent alveolar bone and cementum5. Our laboratory has shown that progenitor cells isolated from PDL tissue by selection with cell surface markers STRO-1+ and CD146+ are capable of differentiating into chondrogenic, osteogenic, and adipogenic phenotypes under appropriate culture conditions6.

Christina Springstead Scanlon

2011-01-01

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A periodontal ligament driven remodeling algorithm for orthodontic tooth movement.  

Science.gov (United States)

While orthodontic tooth movement (OTM) gains considerable popularity and clinical success, the roles played by relevant tissues involved, particularly periodontal ligament (PDL), remain an open question in biomechanics. This paper develops a soft-tissue induced external (surface) remodeling procedure in a form of power law formulation by correlating time-dependent simulation in silico with clinical data in vivo (pprocedure. This algorithm was found rather indicative and effective to simulate OTM under different loading conditions, which is of considerable potential to predict therapeutical outcomes and develop a surgical plan for sophisticated orthodontic treatment. PMID:24703301

Chen, Junning; Li, Wei; Swain, Michael V; Ali Darendeliler, M; Li, Qing

2014-05-01

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The Immunomodulatory Properties of Periodontal Ligament Stem Cells Isolated from Inflamed Periodontal Granulation.  

Science.gov (United States)

Periodontitis is currently the main cause of tooth loss and as yet there is no appropriate method for establishing a functional and predictable periodontal regeneration. Tissue engineering involving seed cells provides a new prospect for periodontal regeneration. While periodontal ligament stem cells (PDLSCs) are a good choice for seed cells, it is not always possible to obtain the patients' own PDLSCs. We and others have found a type of stromal cells from inflamed periodontal granulation. These cells displayed similar differentiation properties to PDLSCs. Inflammation has a profound influence on the immunomodulatory properties of mesenchymal stem cells, which may affect therapeutic outcome. In this study, we assessed the immunomodulatory characteristics of these inflamed human (ih)PDLSCs. Along with the similarity in cell surface marker expressions, they also displayed immunomodulatory properties comparable to those in healthy human (hh)PDLSCs. Both hhPDLSCs and ihPDLSCs can suppress the proliferation and secretion of IFN-? in peripheral blood mononuclear cells by indirect soluble mediators and direct cell-cell contact. Albeit with some quantitative variances, the gene expressions of inducible nitric oxide synthases, indoleamine 2,3 dioxygenase, cyclooxygenase-2, TNF-?-induced protein 6 and IL-10 in ihPDLSCs displayed similar patterns as those in hhPDLSCs. Taken together, our results suggest that ihPDLSCs can provide a promising alternative to hhPDLSCs in terms of evident similarities in immunomodulatory properties as well as their easier accessibility and availability. © 2014 S. Karger AG, Basel. PMID:25471814

Li, Chenghua; Wang, Xinwen; Tan, Jun; Wang, Tao; Wang, Qintao

2014-11-29

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Periodontal Ligament Cell Sheet Engineering: A new Possible Strategy to Promote Periodontal Regeneration  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction: Osseointegration represents a direct structural and functional connection between ordered, living bone and the surface of a load-carrying implant without the periodontium. As a result, im-plant fracture or aggressive bone loss sometime occurs because the patient cannot feel the mechanical overloads exerted on the implant. Until now, no available method has been used to solve this problem.The hypothesis: Periodontal ligament (PDL cells are a desirable cell population capable of regenerating a functional periodontal at-tachment apparatus. Cell sheet engineering has emerged as a novel alternative approach for periodontal tissue engineering without the disruption of both critical cell surface proteins such as ion channels, growth factor receptors and cell-to-cell junction proteins. PDL cells can be isolated from an extracted tooth and can be cultured on temperature-responsive culture dishes at 37°C. Transplantable cell sheets can be harvested by reducing the temperature to 20°C, and would be transplanted into the implant beds before insertion of the implant.Evaluation of the hypothesis: Controlling the differentiation of PDL cell sheets to different functional peri-implant periodontal tissues is very difficult. Further studies are required to determine the fate of implanted cells. Fluorescence protein-labeled cell sheets would be a good approach to investigate the fate of the grafted cell sheet.

Dong-sheng Zhang

2010-06-01

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Effect of Therapeutic Ultrasound on Human Periodontal Ligament Cells for Dental and Periodontal Tissue Engineering  

OpenAIRE

The objective of this study was to investigate whether low intensity pulsed ultrasound (LIPUS) has anabolic effects on human periodontal ligament (PDL) cells. The PDL cells were plated in 48-well plates and cultured at 37°C in an atmosphere of 5% CO2 in air, in a humidified incubator until confluent. The cells were divided into three groups including control, 5 min and 10 min ultrasound application. The LIPUS was applied using a 2.5 transducer that produces an incident intensity of 30 mW/cm2...

El-bialy, Tarek; Alhadlaq, Adel; Lam, Brian

2012-01-01

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Function of Chemokine (CXC Motif) Ligand 12 in Periodontal Ligament Fibroblasts  

OpenAIRE

The periodontal ligament (PDL) is one of the connective tissues located between the tooth and bone. It is characterized by rapid turnover. Periodontal ligament fibroblasts (PDLFs) play major roles in the rapid turnover of the PDL. Microarray analysis of human PDLFs (HPDLFs) and human dermal fibroblasts (HDFs) demonstrated markedly high expression of chemokine (CXC motif) ligand 12 (CXCL12) in the HPDLFs. CXCL12 plays an important role in the migration of mesenchymal stem cells (MSCs). The fun...

Yashiro, Yuichi; Nomura, Yoshiaki; Kanazashi, Mikimoto; Noda, Koji; Hanada, Nobuhiro; Nakamura, Yoshiki

2014-01-01

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Dental trauma involving root fracture and periodontal ligament injury: a 10-year retrospective study  

OpenAIRE

The purpose of this retrospective study was to analyze the cases of traumatic dental injuries involving root fracture and/or periodontal ligament injury (except avulsion) treated at the Discipline of Integrated Clinic, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Brazil, from January 1992 to December 2002. Clinical and radiographic records from 161 patients with 287 traumatized teeth that had sustained root fracture and/or injuries to the periodontal ligament were e...

Sônia Regina Panzarini; Denise Pedrini; Wilson Roberto Poi; Celso Koogi Sonoda; Daniela Atili Brandini; José Carlos Monteiro de Castro

2008-01-01

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Stereological Analysis of the Dental Pulp in Patients with Advanced Periodontitis  

OpenAIRE

Background: The adverse effects of periodontitis on dental pulp have long been argued. The purpose of this study was to investigate stereological indices of dental pulp in patients with advanced periodontitis compared with healthy people. Materials and Methods: In this case-control study, 15 single-rooted permanent teeth of patients with advanced periodontal diseases and that of people with healthy periodontium, as control group, were investigated. All teeth were intact, and without filling a...

Zahra Heidari; Eshagh Ali Saberi; Hamidreza Mahmoudzadeh-Sagheb; Narges Farhad-Mollashahi; Firouz Zadfatah

2013-01-01

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Effect of storage media on the proliferation of periodontal ligament fibroblasts  

International Nuclear Information System (INIS)

The effect of storage media, which are routinely used in replantation, upon the proliferative capacity of periodontal ligament fibroblasts, was compared with the effect of a tissue culture medium. The periodontal tissue was obtained from mandibular central incisors of White New Zealand rabbits. The experiments were performed in fibroblasts derived during second subculture. The storage media were physiologic salt solution, Ringer's solution and Rivanol; the tissue culture medium was alpha-minimum essential medium without nucleosides. The incubation period was 1 hour. [3H]-thymidine incorporation and cell counts were taken to indicate changes in the proliferative capacity of the fibroblasts. The tissue culture experiments showed that the proliferative ability of the periodontal ligament fibroblasts was dependent upon the composition of the storage medium. Physiologic salt solution, Ringer's solution and Rivanol were unable to maintain the metabolism of the fibroblasts. alpha-MEM medium, however, was capable of stimulating proliferation of the periodontal ligament fibroblasts

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Morinda citrifolia leaves enhance osteogenic differentiation and mineralization of human periodontal ligament cells.  

Science.gov (United States)

This present study investigated the potential of Morinda citrifolia leaf aqueous extract to induce osteogenic differentiation and matrix mineralization of human periodontal ligament (hPDL) cells. Human periodontal ligament cells were cultured in complete medium, ascorbic acid with ?-glycerophosphate, or Morinda citrifolia leaf aqueous extract. Morinda citrifolia leaf aqueous extract significantly increased alkaline phosphatase activity compared to culturing in complete medium or ascorbic acid with ?-glycerophosphate. Matrixcontaining mineralized nodules were formed only when the cells were cultured in the presence of Morinda citrifolia leaf aqueous extract. These nodules showed positive alizarin red S staining and were rich in calcium and phosphorus according to energy dispersive X-ray analysis. In conclusion, Morinda citrifolia leaf extract promoted osteogenic differentiation and matrix mineralization in human periodontal ligament cells, a clear indication of the therapeutic potential of Morinda citrifolia leaves in bone and periodontal tissue regeneration. PMID:24682022

Boonanantanasarn, Kanitsak; Janebodin, Kajohnkiart; Suppakpatana, Prapan; Arayapisit, Tawepong; Rodsutthi, Jit-aree; Chunhabundit, Panjit; Boonanuntanasarn, Surintorn; Sripairojthikoon, Wanida

2014-01-01

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Chondrogenesis of periodontal ligament stem cells by transforming growth factor-?3 and bone morphogenetic protein-6 in a normal healthy impacted third molar  

OpenAIRE

The periodontal ligament-derived mesenchymal stem cell is regarded as a source of adult stem cells due to its multipotency. However, the proof of chondrogenic potential of the cells is scarce. Therefore, we investigated the chondrogenic differentiation capacity of periodontal ligament derived mesenchymal stem cells induced by transforming growth factor (TGF)-?3 and bone morphogenetic protein (BMP)-6. After isolation of periodontal ligament stem cells (PDLSCs) from human periodontal ligament,...

Choi, Sunyoung; Cho, Tae-jun; Kwon, Soon-keun; Lee, Gene; Cho, Jaejin

2013-01-01

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An immunohistochemical, histological, and electron-microscopic study of the human periodontal ligament during orthodontic treatment.  

Science.gov (United States)

The periodontal ligament lies between the hard tissues of alveolar bone and cementum of teeth and serves to anchor the tooth to the alveolus and functions as a cushion between these hard tissues to migrate occlusal force during mastication. This tissue is always exposed to mechanical stress during mastication. When occlusal forces exceed the adaptive capacity of the periodontal ligament, the periodontal ligament tissue will be injured and then occlusal trauma will occur. The different modifications of periodontal ligament during load deformation can be monitored by analysis of the expression of different collagen types and fibronectin, with immunohistochemical techniques, and by morphological study of ligament, with light- and transmission electron-microscopic techniques. The use of continued and light orthodontic force generates a pressure of ligament with ejection of parodontal fluid externally and partial closing of vessels. On these basis we performed a study in order to evaluate periodontal ligament collagen types I and IV and the fibronectin modifications induced by application of a precalibrated orthodontic strength. We integrated these results, with light and transmission electron-microscopic observations, in order to evaluate the morphological modifications of periodontal tissue. Our observations showed that the type I collagen immunofluorescence staining is increased in the pressure side; in the tension side, it shows prior to treatment an increase, and after 72 h of treatment, a diminution of the staining pattern. Type IV collagen staining is reduced in both sides, but increased gradually after 7 days from treatment; finally, fibronectin staining pattern is gradually increased in the pressure side and reduced in the tension side. In light and transmission electron-microscopic observations it is possible to show a reduction of vessels at 72 h from treatment, and an increase of vessels after 7 days from treatment. The Malassez's epithelial residues are decreased at 72 h, while they are increased after 7 days from treatment. The modifications of immunofluorescence staining patterns of tested proteins revealed angiogenesis and reparative processes, and a thickening of fibrillar matrix as a defensive reply to mechanical stress. The modification of normal staining patterns of tested protein in our observations, could be determined by variation of scaffold geometry of periodontal ligament. The reduced movements of contraction and relaxation of periodontal ligament, due to orthodontic treatment, provoke a loss of mechanical stresses transmitted over ligament surface. Mechanical signals, therefore, could be integrated with other environmental signals and transduced into biochemical signals through force-dependent changes in scaffold geometry. Physical forces of gravity, hemodynamic stresses, and movement play a critical role in tissues, since the cells use tensegrity architecture for their structural organization. PMID:18425345

Anastasi, Giuseppe; Cordasco, Giancarlo; Matarese, Giovanni; Rizzo, Giuseppina; Nucera, Riccardo; Mazza, Manuela; Militi, Angela; Portelli, Marco; Cutroneo, Giuseppina; Favaloro, Angelo

2008-05-01

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Dental trauma involving root fracture and periodontal ligament injury: a 10-year retrospective study  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The purpose of this retrospective study was to analyze the cases of traumatic dental injuries involving root fracture and/or periodontal ligament injury (except avulsion) treated at the Discipline of Integrated Clinic, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Brazil, fro [...] m January 1992 to December 2002. Clinical and radiographic records from 161 patients with 287 traumatized teeth that had sustained root fracture and/or injuries to the periodontal ligament were examined. The results of this survey revealed that subluxation (25.09%) was the most common type of periodontal ligament injury, followed by extrusive luxation (19.86%). There was a predominance of young male patients and most of them did not present systemic alterations. Among the etiologic factors, the most frequent causes were falls and bicycle accidents. Injuries on extraoral soft tissues were mostly laceration and abrasion, while gingival and lip mucosa lacerations prevailed on intraoral soft tissues injuries. Radiographically, the most common finding was an increase of the periodontal ligament space. The most commonly performed treatment was root canal therapy. Within the limits of this study, it can be concluded that traumatic dental injuries occur more frequently in young male individuals, due to falls and bicycle accidents. Subluxation was the most common type of periodontal ligament injury. Root canal therapy was the type of treatment most commonly planned and performed.

Sônia Regina, Panzarini; Denise, Pedrini; Wilson Roberto, Poi; Celso Koogi, Sonoda; Daniela Atili, Brandini; José Carlos Monteiro de, Castro.

2008-09-01

27

Dental trauma involving root fracture and periodontal ligament injury: a 10-year retrospective study  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this retrospective study was to analyze the cases of traumatic dental injuries involving root fracture and/or periodontal ligament injury (except avulsion treated at the Discipline of Integrated Clinic, School of Dentistry of Araçatuba, São Paulo State University (UNESP, Brazil, from January 1992 to December 2002. Clinical and radiographic records from 161 patients with 287 traumatized teeth that had sustained root fracture and/or injuries to the periodontal ligament were examined. The results of this survey revealed that subluxation (25.09% was the most common type of periodontal ligament injury, followed by extrusive luxation (19.86%. There was a predominance of young male patients and most of them did not present systemic alterations. Among the etiologic factors, the most frequent causes were falls and bicycle accidents. Injuries on extraoral soft tissues were mostly laceration and abrasion, while gingival and lip mucosa lacerations prevailed on intraoral soft tissues injuries. Radiographically, the most common finding was an increase of the periodontal ligament space. The most commonly performed treatment was root canal therapy. Within the limits of this study, it can be concluded that traumatic dental injuries occur more frequently in young male individuals, due to falls and bicycle accidents. Subluxation was the most common type of periodontal ligament injury. Root canal therapy was the type of treatment most commonly planned and performed.

Sônia Regina Panzarini

2008-09-01

28

Stress-relaxation and microscopic dynamics of rabbit periodontal ligament.  

Science.gov (United States)

The aim of the present study was to examine the structural basis for the stress-relaxation behaviour of the periodontal ligament (PDL). Seventeen 4-month-old rabbits were used. A tooth-PDL-bone segment was cut in a rectangular prism from the incisor of a dissected mandible. The specimen was mounted in a testing machine built on a video stereomicroscope. Following preconditioning, each specimen was stretched to a deformation of 35 microm and then the deformation was kept constant for 300 s to obtain a stress-relaxation curve. Thereafter, stress-relaxation tests were repeated sequentially at deformations of 55, 75, and 95 microm. Polarised-light video-stereomicroscopic images of the specimens were simultaneously recorded and analysed with the stress-relaxation curves. The image analysis revealed that during stress-relaxation, the brightness of the birefringent fibres tended to initially increase rapidly and then do so gradually. There were negative correlations between the brightness and relaxation modulus at the four deformations. The decreases of normalised relaxation modulus for 300 s were less at greater deformation levels. The stress-relaxation process was well described by a function with three exponential decay terms and a constant. These findings suggest that during stress-relaxation of the PDL, the alignment of the collagen molecules and fibrils within the stretched fibres may occur, which could be driven by the strain energy imparted to the specimen on initial stretching. PMID:16564051

Komatsu, K; Sanctuary, C; Shibata, T; Shimada, A; Botsis, J

2007-01-01

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Degenerative alterations of the cementum-periodontal ligament complex and early tooth loss in a young patient with periodontal disease.  

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Premature exfoliation of primary or permanent teeth in children or adolescents is extremely rare and it can be a manifestation of an underlying systemic disease. This study aims to present the histological aspects associated with early tooth loss in a case of periodontal disease developed without local inflammation and with minimal periodontal pockets and attachment loss. The maxillary left second premolar was extracted together with a gingival collar attached to the root surface. The histological analysis recorded the resorption of the cementum in multiple areas of the entire root surface with the connective tissue of the desmodontium invading the lacunae defects. The connective tissue rich in cells occupied the periodontal ligamentar space and the resorptive areas. No inflammation was obvious in the periodontal ligament connective tissue. This report may warn clinicians about the possibility of the association of cemental abnormalities with early tooth loss. PMID:23303038

Petru?iu, S A; Buiga, Petronela; Roman, Alexandra; Danciu, Theodora; Mihu, Carmen Mihaela; Mihu, D

2012-01-01

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Effect of F-spondin on cementoblastic differentiation of human periodontal ligament cells  

International Nuclear Information System (INIS)

Cementum is a mineralized tissue produced by cementoblasts covering the roots of teeth that provides for the attachment of periodontal ligament to roots and surrounding alveolar bone. To study the mechanism of proliferation and differentiation of cementoblasts is important for understanding periodontal physiology and pathology including periodontal tissue regeneration. However, the detailed mechanism of the proliferation and differentiation of human cementoblasts is still unclear. We previously established human cementoblast-like (HCEM) cell lines. We thought that comparing the transcriptional profiles of HCEM cells and human periodontal ligament (HPL) cells derived from the same teeth could be a good approach to identify genes that influence the nature of cementoblasts. We identified F-spondin as the gene demonstrating the high fold change expression in HCEM cells. Interestingly, F-spondin highly expressing HPL cells showed similar phenotype of cementoblasts, such as up-regulation of mineralized-related genes. Overall, we identified F-spondin as a promoting factor for cementoblastic differentiation

31

The Effect of Cultured Autologous Periodontal Ligament Cells on the Healing of Delayed Autotransplanted Dog's Teeth  

OpenAIRE

Introduction: The regeneration of the periodontal structure for avulsed teeth extended dry times has been a goal of dentists. The aim of this study was to investigate a new strategy of delayed replantation for avulsed teeth that were not suitable for immediate replantation. Methods: Extracted dog's premolar teeth were maintained in a dry environment for a month after isolation and proliferation of the periodontal ligament (PDL) cells. Then, tooth roots coated with 1 × 106 cultured autologous...

Wang, Y.; Cheung, Gsp; Xu, X.; Zhao, S.; Zhang, C.

2010-01-01

32

EVALUATION OF HISTOPATHOLOGIC CHANGES OF DENTAL PULP IN ADVANCED PERIODONTAL DISEASES  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract- The adverse effects of periodontal disease on dental pulp has been debated for many years. This case- control study was performed to assess the possible effects of advanced periodontal disease on the structure of dental pulp. Fifty-two permanent teeth extracted because of advanced periodontitis with ? 5mm attachment loss and grade III mobility were compared to fifty-two control teeth, obtained from systemically healthy adults. Two groups were matched for age and teeth types. Inflammation, fibrosis, calcification and necrosis were observed in the (27.8- 40%, (0-59.4%, (0-26.4% and (0-20.9% of the different sections of the study group, and (0%, (9.7-50%, (0-11.6% and (0% of the control group (P < 0.05. Abnormal pulp tissue was observed in the (33.3-88.1% and (12.9-50.5% of different sections of the study and control groups respectively (P < 0.05. Complete necrosis of dental pulp occurred only when depth of adjacent periodontal pocket reached the apical third of the root. There was an increase in frequency of pathologic changes as the depth of periodontal pocket increased (P = 0.00. We conclude that advanced periodontal disease can affect the dental pulp, although not necessarily leading to complete pulp disintegration. Careful consideration of diagnostic and treatment planning in patients with endodontic-periodontal involvement is recommended. Fibrosis and diffuse calcification of dental pulp in teeth with advanced periodontal involvement may endanger root canal therapy; if needed.

M. S. Sheykhrezaee

2007-05-01

33

An experimental study on the effect of irradiation on deciduous dental pulp and periodontal membrane  

International Nuclear Information System (INIS)

Left mandibular third deciduous molars of young dogs were irradiated for 3,000 R with 200 kVp X-ray and the effect on the dental pulp and periodontal membrane was investigated histopathologically. 1. From 3rd to 7th days after irradiation, localized inflammatory cell infiltration was observed in part in the dental pulp tissue. No abnormal findings were observed in the periodontal membrane. 2. On 14th day after irradiation in the coronal dental pulp, cells decreased; karyopycnosis occurred; cells were connected only by cellular processes, and large and small reticular networks were formed. In the periodontal membrane, fibers ran irregularly although in part and findings of atrophy were seen. Fibroblasts showed a decreasing tendency. 3. In the cases from 1 to 2 months after irradiation, the pulp tissue showed marked atrophy of odontoblasts and the dental pulp showed hyalinization-like changes. In the periodontal membrane, Sharpey's fibers ran irregularly or became indistinct, and fibroblasts decreased extensively. The periodontal membrane in general showed hyalinization. 4. In the cases of 4 months after irradiation, the pulp tissue on the whole showed marked atrophy and disappearance of odontoblast layers. In the periodontal membrane, inflammatory cell infiltration was seen in part and membrane fibers, as those in 2nd month, showed marked atrophy, became enlarged, and presented findings of hyalinization. 5. At 8th month, the necleoli nearly disappeared in the pulp tissue from the crown to the root and the cells were connected like filaments by cellular processes. Nearly all the blood vessels and fibers disappeared. In the periodontal membrane, most of Sharpey's fibers disappeared. Fibroblasts showed marked atrophy and disappearance, and few normal fibloblasts could be found. (J.P.N.)

34

Stereological Analysis of the Dental Pulp in Patients with Advanced Periodontitis  

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Full Text Available Background: The adverse effects of periodontitis on dental pulp have long been argued. The purpose of this study was to investigate stereological indices of dental pulp in patients with advanced periodontitis compared with healthy people. Materials and Methods: In this case-control study, 15 single-rooted permanent teeth of patients with advanced periodontal diseases and that of people with healthy periodontium, as control group, were investigated. All teeth were intact, and without filling and decay. After tissue processing, longitudinal serial sections of the tooth were prepared and stained by Masson’s trichrome. A grid containing organized points superimposed on the images of each section randomly. Then, the points hit with each subject were counted. The volume of pulp and its components in both groups were estimated, using Cavalieri’s principle. Data were analyzed using Mann-Whitney U test. The significance level was considered as p<0.05.Results: No significant difference was observed between the groups in terms of inflammation and calcification intensity (p<0.05. Microscopic evaluations of tissue sections showed significant increase in predentin thickness in periodontitis group than control group (p<0.05. In addition, statistically significant reduction was observed in periodontitis group with respect to pulp absolute volume, volume density, odontoblastic layer absolute volume, collagen fibers absolute volume, and absolute pulp blood vessels volume, compared with control group (p<0.05.Conclusion: Results showed periodontal disease affects stereological parameters of pulp. Because of reduction of pulp volume and narrowing of root canal, precise diagnostic and therapeutic considerations are recommended during treatment of those teeth.

Zahra Heidari

2013-07-01

35

Advanced glycation end products (AGEs) and their receptor (RAGE) induce apoptosis of periodontal ligament fibroblasts  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Diabetics have an increased prevalence of periodontitis, and diabetes is one of the causative factors of severe periodontitis. Apoptosis is thought to be involved in this pathogenic relationship. The aim of this study was to investigate apoptosis in human periodontal ligament (PDL) fibroblasts induc [...] ed by advanced glycation end products (AGEs) and their receptor (RAGE). We examined the roles of apoptosis, AGEs, and RAGE during periodontitis in diabetes mellitus using cultured PDL fibroblasts that were treated by AGE-modified bovine serum albumin (AGE-BSA), bovine serum albumin (BSA) alone, or given no treatment (control). Microscopy and real-time quantitative PCR indicated that PDL fibroblasts treated with AGE-BSA were deformed and expressed higher levels of RAGE and caspase 3. Cell viability assays and flow cytometry indicated that AGE-BSA reduced cell viability (69.80±5.50%, P

D.X., Li; T.Z., Deng; J., Lv; J., Ke.

2014-09-19

36

Advanced glycation end products (AGEs) and their receptor (RAGE) induce apoptosis of periodontal ligament fibroblasts  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Diabetics have an increased prevalence of periodontitis, and diabetes is one of the causative factors of severe periodontitis. Apoptosis is thought to be involved in this pathogenic relationship. The aim of this study was to investigate apoptosis in human periodontal ligament (PDL) fibroblasts induc [...] ed by advanced glycation end products (AGEs) and their receptor (RAGE). We examined the roles of apoptosis, AGEs, and RAGE during periodontitis in diabetes mellitus using cultured PDL fibroblasts that were treated by AGE-modified bovine serum albumin (AGE-BSA), bovine serum albumin (BSA) alone, or given no treatment (control). Microscopy and real-time quantitative PCR indicated that PDL fibroblasts treated with AGE-BSA were deformed and expressed higher levels of RAGE and caspase 3. Cell viability assays and flow cytometry indicated that AGE-BSA reduced cell viability (69.80±5.50%, P

D.X., Li; T.Z., Deng; J., Lv; J., Ke.

1036-10-01

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Effect of root and bone morphology on the stress distribution in the periodontal ligament.  

Science.gov (United States)

To achieve predictable and physiologic orthodontic tooth movement, estimating the axis of rotation of a tooth and the level and location of maximum stress distributed in the periodontal ligament is essential. An extracted upper canine was scanned into a computer 2-dimensionally and divided into 80 nodes along the long axis of the tooth. A mathematical formula was derived, and stress was calculated on each node. The purpose of this study was to reveal the center of resistance, axis of rotation, and an ideal force magnitude associated with various periodontal conditions, such as potential root resorption, alveolar bone loss, and varying anatomic root shape by analyzing the stress distribution in the periodontal ligament. The study demonstrates that the location of center of resistance changes significantly with variation of shape and length of the root embedded in alveolar bone. In contrast, in response to alveolar bone loss, the relative location of the center of resistance to total root length remains constant. Analysis of the stress distribution pattern in our 2-dimensional model reveals that the relationship between location of force and axis of rotation is determined by s(2) (that is) a constant depends on shape and length of a root in alveolar bone. Tapered and short roots that result from alveolar bone loss or apical root resorption are prone to tipping. The optimal orthodontic force may vary depending on the maximum stress in the periodontal ligament. PMID:10629526

Choy, K; Pae, E K; Park, Y; Kim, K H; Burstone, C J

2000-01-01

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A low-level diode laser therapy reduces the lipopolysaccharide (LPS)-induced periodontal ligament cell inflammation  

Science.gov (United States)

The purpose of this study was to investigate the cytologic effects of inflammatory periodontal ligament cells in vitro after low-level laser therapy. Human periodontal ligament cells were cultured, exposed to lipopolysaccharide and subjected to low-level laser treatment of 5?J?cm?2 or 10?J?cm?2 using a 920?nm diode laser. A periodontal ligament cell attachment was observed under a microscope, and the cell viability was quantified by a mitochondrial colorimetric assay. Lipopolysaccharide-treated periodontal ligament cells were irradiated with the low-level laser, and the expression levels of several inflammatory markers, iNOS, TNF-? and IL-1, and pErk kinase, were analyzed by reverse transcription polymerase chain reaction and western blot. The data were collected and analyzed by one-way analysis of variance; p low-level laser treatment of periodontal ligament cells increased their ability to attach and survive. After irradiation, the expression levels of iNOS, TNF-? and IL-1 in lipopolysaccharide-exposed periodontal ligament cells decreased over time (p low-level diode laser treatment increased the cells’ proliferative ability and decreased the expression of the examined inflammatory mediators.

Huang, T. H.; Chen, C. C.; Liu, S. L.; Lu, Y. C.; Kao, C. T.

2014-07-01

39

Crucial role of Notch signaling in osteogenic differentiation of periodontal ligament stem cells in osteoporotic rats.  

Science.gov (United States)

Estrogen deficiency-induced osteoporosis typically occurs in postmenopausal women and has been strongly associated with periodontal diseases. Periodontal ligament stem cells (PDLSCs) isolated from the periodontal ligament can differentiate into many types of specialized cells, including osteoblast-like cells that contribute to periodontal tissue repair. The Notch signaling pathway is highly conserved and associated with self-renewal potential and cell-fate determination. Recently, several studies have focused on the relationship between Notch signaling and osteogenic differentiation. However, the precise mechanisms underlying this relationship are largely unknown. We have successfully isolated PDLSCs from both ovariectomized (OVX) and sham-operated rats. Both the mRNA and protein levels of Notch1 and Jagged1 were upregulated when PDLSCs were cultured in osteogenic induction media. Mineralization assays showed decreased calcium deposits in OVX-PDLSCs treated with a ?-secretase inhibitor compared with control cells. Thus Notch signaling is important in maintaining the osteogenic differentiation of PDLSCs in osteoporotic rats, which help in the development of a potential therapeutic strategy for periodontal disease in postmenopausal women. PMID:24677709

Li, Ying; Li, S Q; Gao, Y M; Li, Jin; Zhang, Bin

2014-06-01

40

Proliferation of the human periodontal ligament fibroblast by laser biostimulation: an in vitro study  

Science.gov (United States)

Laser produces a monochormatic collimated and coherent radiation. In dentistry, diode lasers have been used predominantly for application which are broadly termed "Low level laser therapy (LLLT) or biostimulation (L.J. Walch 1997)". Periodontal ligament fibroblast (PDLF) have a key function in periodontal regeneration. Stimulatory effects on the proliferation of these cells could therefore be beneficial for the reestablishment of connective tissue attachment. The aim of this in vitro study was to evaluate the potential stimulatory effect of low level laser irradiation on the proliferation of PDLF.

Shelly, Ahuja; Shaila, Kothiwale; Kishore, Bhat

2006-02-01

41

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

Science.gov (United States)

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 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 < 0.05). Again, increased periodontal destruction was not necessarily followed by a decrease in the amount of dentin- and pulp-like tissue formed. These findings provide preliminary evidence that periodontally compromised teeth might contain putative stem cells with certain MSC properties, as long as the vitality of the pulp has not been totally damaged. Whether these cells can serve as a source of autologous multipotent MSCs for clinical regenerative therapies warrants further investigation with larger sample sizes and various types of periodontitis. PMID:25172527

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

42

In vitro human periodontal ligament-like tissue formation with porous poly-L-lactide matrix  

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This study aimed to establish an in vitro human periodontal ligament-like tissue (HPdLLT) by three-dimensional culturing of human periodontal ligament fibroblasts (HPdLFs) in a porous poly-L-lactide (PLLA) matrix modified hydrophilically with ammonia solution. After ammonia modification, the surface roughness and culture-medium-soaking-up ability of the PLLA matrix increased, whereas the contact angle of water drops decreased. The thickness, porosity, and pore size of the PLLA matrix were 400 ± 50 ?m, 83.3%, and 75–150 ?m, respectively. HPdLFs (1 × 10{sup 5} cells) were seeded on the modified PLLA matrix and centrifuged to facilitate seeding into its interior and cultured for 14 days. Scanning electron microscope (SEM) observation, proliferation assay, picrosirius-red staining, and real-time polymerase chain reaction (RT-PCR) for type-1 collagen (COL1), periodontal ligament associated protein-1 (PLAP-1), fibroblast growth factor-2 (FGF-2), and alkaline phosphatase (ALP) mRNA were conducted on days 1, 3, 7, and 14. HPdLFs were observed entirely from the surface to the rear side of the matrix. Cell proliferation analysis, SEM observation, and picrosirius-red staining showed both progressive growth of 3D-cultured HPdLFs and extracellular matrix maturation by the secretion of COL1 and type 3 collagen (COL3) from days 1 to 14. Expressions of COL1, PLAP-1, and FGF-2 mRNA suggested the formation of cellular components and supplementation of extracellular components. Expressions of ALP, COL1, and PLAP-1 mRNA suggested the osteogenic potential of the HPdLLT. The results indicated in vitro HPdLLT formation, and it could be used in future periodontal ligament tissue engineering to achieve optimal periodontal regeneration. - Highlights: • First report on ammonia treated PLLA matrix for in vitro human periodontal ligament-like tissue generation. • Good combination of matrix thickness, pore size, and porosity. • Biodegradable PLLA is also possible to be used in vivo.

Liao, Wen [Graduate School of Dentistry, Department of Orthodontics, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata-shi, Osaka-fu 573-1121 (Japan); Okada, Masahiro [Department of Biomaterials, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata-shi, Osaka-fu 573-1121 (Japan); Sakamoto, Fumito; Okita, Naoya [Graduate School of Dentistry, Department of Orthodontics, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata-shi, Osaka-fu 573-1121 (Japan); Inami, Kaoru; Nishiura, Aki [Department of Orthodontics, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata-shi, Osaka-fu 573-1121 (Japan); Hashimoto, Yoshiya, E-mail: yoshiya@cc.osaka-dent.ac.jp [Department of Biomaterials, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata-shi, Osaka-fu 573-1121 (Japan); Matsumoto, Naoyuki [Department of Orthodontics, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata-shi, Osaka-fu 573-1121 (Japan)

2013-08-01

43

In vitro human periodontal ligament-like tissue formation with porous poly-L-lactide matrix  

International Nuclear Information System (INIS)

This study aimed to establish an in vitro human periodontal ligament-like tissue (HPdLLT) by three-dimensional culturing of human periodontal ligament fibroblasts (HPdLFs) in a porous poly-L-lactide (PLLA) matrix modified hydrophilically with ammonia solution. After ammonia modification, the surface roughness and culture-medium-soaking-up ability of the PLLA matrix increased, whereas the contact angle of water drops decreased. The thickness, porosity, and pore size of the PLLA matrix were 400 ± 50 ?m, 83.3%, and 75–150 ?m, respectively. HPdLFs (1 × 105 cells) were seeded on the modified PLLA matrix and centrifuged to facilitate seeding into its interior and cultured for 14 days. Scanning electron microscope (SEM) observation, proliferation assay, picrosirius-red staining, and real-time polymerase chain reaction (RT-PCR) for type-1 collagen (COL1), periodontal ligament associated protein-1 (PLAP-1), fibroblast growth factor-2 (FGF-2), and alkaline phosphatase (ALP) mRNA were conducted on days 1, 3, 7, and 14. HPdLFs were observed entirely from the surface to the rear side of the matrix. Cell proliferation analysis, SEM observation, and picrosirius-red staining showed both progressive growth of 3D-cultured HPdLFs and extracellular matrix maturation by the secretion of COL1 and type 3 collagen (COL3) from days 1 to 14. Expressions of COL1, PLAP-1, and FGF-2 mRNA suggested the formation of cellular components and supplementation of extracellular components. Expressions of ALP, COL1, and PLAP-1 mRNA suggested the osteogenic potential of the HPdLLT. The results indicated in vitro HPdLLT formation, and it could be used in future periodontal ligament tissue engineering to achieve optimal periodontal regeneration. - Highlights: • First report on ammonia treated PLLA matrix for in vitro human periodontal ligament-like tissue generation. • Good combination of matrix thickness, pore size, and porosity. • Biodegradable PLLA is also possible to be used in vivo

44

Comparative gene expression analysis of the human periodontal ligament in deciduous and permanent teeth  

OpenAIRE

There are histological and functional differences between human deciduous and permanent periodontal ligament (PDL) tissues. The aim of this study was to determine the differences between these two types of tissue at the molecular level by comparing their gene expression patterns. PDL samples were obtained from permanent premolars (n?=?38) and anterior deciduous teeth (n?=?31) extracted from 40 healthy persons. Comparative cDNA microarray analysis revealed several differences in gene e...

Song, Je Seon; Hwang, Dong Hwan; Kim, Seong-oh; Jeon, Mijeong; Choi, Byung-jai; Jung, Han-sung; Moon, Seok Jun; Park, Wonse; Choi, Hyung-jun

2013-01-01

45

Proliferation and osteogenic differentiation of human periodontal ligament cells on akermanite and ?-TCP bioceramics  

OpenAIRE

The purpose of this study was to investigate the effects of akermanite as compared to ?-TCP on attachment, proliferation, and osteogenic differentiation of human periodontal ligament cells (hPDLCs). Scanning electron microscopy (SEM) and actin filament labeling were used to reveal attachment and growth of hPDLCs seeded on ?-TCP and akermanite ceramic. Cell proliferation was tested by lactic acid production and MTT analysis, while osteogenic differentiation was assayed by alkaline phosphatas...

Xia, L.; Zhang, Z.; Chen, L.; Zhang, W.; Zeng, D.; Zhang, X.; Chang, J.; Jiang, X.

2011-01-01

46

Comparative Gene-Expression Analysis of the Dental Follicle and Periodontal Ligament in Humans  

OpenAIRE

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 relat...

Lee, Hyo-seol; Lee, Jongeun; Kim, Seong-oh; Song, Je-seon; Lee, Jae-ho; Lee, Syng-ill; Jung, Han-sung; Choi, Byung-jai

2013-01-01

47

Experimentally Determined Mechanical Properties of, and Models for, the Periodontal Ligament: Critical Review of Current Literature  

OpenAIRE

Introduction. This review is intended to highlight and discuss discrepancies in the literature of the periodontal ligament's (PDL) mechanical properties and the various experimental approaches used to measure them. Methods. Searches were performed on biomechanical and orthodontic publications (in databases: Compendex, EMBASE, MEDLINE, PubMed, ScienceDirect, and Scopus). Results. The review revealed that significant variations exist, some on the order of six orders of magnitude, in the...

Fill, Ted S.; Carey, Jason P.; Toogood, Roger W.; Major, Paul W.

2011-01-01

48

Experimental study on the effect of x-irradiation in the rat periodontal ligament  

International Nuclear Information System (INIS)

The author studied on the effects of X-ray irradiation to the development of periodontal ligament in gestation rats. They were irradiated in their abdomen with 100, 200 and 300 rads respectively in one shot irradiation with deep radiation therapy equipment(MAXIMAR 250-III). In 7th, 14th, 21th and 28th day after delivery, those new born rats were respectively sacrificed with ether anesthesia and removed of their mandibles. After removal, those mandibles were fixed in 10% neutral buffer formalin, decalcified with 5% trichloroacetic acid for 5 days and embedded with paraffin. Staining was performed with H-E, Van Gieson, Mallory azan, Bielshowsky-Gomori silver stain and Halmi's oxytalan fiber stain. The results were as follows: 1. Before tooth eruption, all the fiber components in dental sac were almost always oriented near the outer enamel epithelial layer. But in irradiated new born rats, those collagen fiber orientation was more irregular than those of control groups, and this phenomenon was more severe in proportion to the amount of irradiation in the gestation period. 2. Before tooth eruption, the connective tissue fibers in periodontal ligament were stained with lighter in the irradiated groups than those of control groups. Oxytalan fibers of irradiated groups were thin and splitting pattern of their fiber morphology to compare with those of control groups. 3. After tooth eruption, the periodontal ligament fibers of irradiated groups were oriented functionally and ted groups were oriented functionally and their morphology was thick, fine and heavy staining. Oxytalan fibers were revealed with oblique parallel arrangement in the periodontal ligament of irradiated groups.

49

Function of chemokine (CXC motif) ligand 12 in periodontal ligament fibroblasts.  

Science.gov (United States)

The periodontal ligament (PDL) is one of the connective tissues located between the tooth and bone. It is characterized by rapid turnover. Periodontal ligament fibroblasts (PDLFs) play major roles in the rapid turnover of the PDL. Microarray analysis of human PDLFs (HPDLFs) and human dermal fibroblasts (HDFs) demonstrated markedly high expression of chemokine (CXC motif) ligand 12 (CXCL12) in the HPDLFs. CXCL12 plays an important role in the migration of mesenchymal stem cells (MSCs). The function of CXCL12 in the periodontal ligament was investigated in HPDLFs. Expression of CXCL12 in HPDLFs and HDFs was examined by RT-PCR, qRT-PCR and ELISA. Chemotactic ability of CXCL12 was evaluated in both PDLFs and HDFs by migration assay of MSCs. CXCL12 was also immunohistochemically examined in the PDL in vivo. Expression of CXCL12 in the HPDLFs was much higher than that in HDFs in vitro. Migration assay demonstrated that the number of migrated MSCs by HPDLFs was significantly higher than that by HDFs. In addition, the migrated MSCs also expressed CXCL12 and several genes that are familiar to fibroblasts. CXCL12 was immunohistochemically localized in the fibroblasts in the PDL of rat molars. The results suggest that PDLFs synthesize and secrete CXCL12 protein and that CXCL12 induces migration of MSCs in the PDL in order to maintain rapid turnover of the PDL. PMID:24806431

Yashiro, Yuichi; Nomura, Yoshiaki; Kanazashi, Mikimoto; Noda, Koji; Hanada, Nobuhiro; Nakamura, Yoshiki

2014-01-01

50

Dentists' level of knowledge of the treatment plans for periodontal ligament injuries after dentoalveolar trauma  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english This study investigated the level of knowledge held by dentists about the possible treatment plan procedures for periodontal ligament injuries after dentoalveolar trauma. A 5-item self-applied questionnaire was prepared with questions referring to the professional profile of the interviewees and to [...] the treatment plan they would propose for periodontal ligament injuries secondary to dentoalveolar trauma. The questionnaires were filled out by 693 dentists attending the 23rd Annual Meeting of the Brazilian Society for Dental Research, and the data obtained were subjected to descriptive analysis. Either the chi-square test or Fisher's exact test was applied to assess associations among variables, at a 5% level of significance. The results revealed that dentists experienced difficulty in establishing a treatment plan for subluxation, and for extrusive, lateral and intrusive luxations. In general, holding a dental specialty degree had no influence on the knowledge about treatment plan procedures for the most severe injuries. It could be concluded that the dentists participating in this study, whether specialists or not, did not have sufficient knowledge to treat most of the periodontal ligament injuries resulting from dentoalveolar trauma adequately.

Denise, Pedrini; Sônia Regina, Panzarini; Wilson Roberto, Poi; Maria Lúcia Marçal Mazza, Sundefeld; Adelisa Rodolfo Ferreira, Tiveron.

2011-08-01

51

Dentists' level of knowledge of the treatment plans for periodontal ligament injuries after dentoalveolar trauma  

Directory of Open Access Journals (Sweden)

Full Text Available This study investigated the level of knowledge held by dentists about the possible treatment plan procedures for periodontal ligament injuries after dentoalveolar trauma. A 5-item self-applied questionnaire was prepared with questions referring to the professional profile of the interviewees and to the treatment plan they would propose for periodontal ligament injuries secondary to dentoalveolar trauma. The questionnaires were filled out by 693 dentists attending the 23rd Annual Meeting of the Brazilian Society for Dental Research, and the data obtained were subjected to descriptive analysis. Either the chi-square test or Fisher's exact test was applied to assess associations among variables, at a 5% level of significance. The results revealed that dentists experienced difficulty in establishing a treatment plan for subluxation, and for extrusive, lateral and intrusive luxations. In general, holding a dental specialty degree had no influence on the knowledge about treatment plan procedures for the most severe injuries. It could be concluded that the dentists participating in this study, whether specialists or not, did not have sufficient knowledge to treat most of the periodontal ligament injuries resulting from dentoalveolar trauma adequately.

Denise Pedrini

2011-08-01

52

Proliferation of human periodontal ligament mesenchymal cells on polished and plasma nitriding titanium surfaces  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english AIM: To evaluate the proliferative capacity of mesenchymal cells derived from human periodontal ligament on polished and plasma-treated titanium surfaces. METHODS: Eighteen titanium disks were polished and half of them (n=9) were submitted to plasma nitriding using the cathodic cage technique. Mesen [...] chymal cells were isolated from periodontal ligament of impacted third molars (n=2) and cultured on titanium disks (polished and nitrided) and on a plastic surface as a positive control of cell proliferation. Cell proliferation was analyzed and growth curves were constructed for the different groups by determining the number of cells adhered to the different surfaces at 24, 48 and 72 h after plating. RESULTS: Higher cell number was observed for the nitrided surface at 24 and 48 h. However, no statistically significant difference in cell proliferation was observed between the two different surface treatments (p>0.05). CONCLUSIONS: We concluded that plasma nitriding produced surfaces that permitted the proliferation of human periodontal ligament mesenchymal cells. Associated to other physical and chemical properties, it is possible to assume the feasibility of plasma nitriding method and its positive effect on the early cellular events of osseointegration.

Rodrigo Alves, Ribeiro; Rodrigo Gadelha, Vasconcelos; Fernanda, Ginani; José Sandro Pereira da, Silva; Clodomiro, Alves-Júnior; Carlos Augusto Galvão, Barboza.

2013-06-01

53

In vitro cytotoxicity of white MTA, MTA Fillapex® and Portland cement on human periodontal ligament fibroblasts.  

Science.gov (United States)

The aim of this study was to compare the in vitro cytotoxicity of white mineral trioxide aggregate (MTA), MTA Fillapex® and Portland cement (PC) on human cultured periodontal ligament fibroblasts. Periodontal ligament fibroblast culture was established and the cells were used for cytotoxic tests after the fourth passage. Cell density was set at 1.25 X10 4 cells/well in 96-well plates. Endodontic material extracts were prepared by placing sealer/cement specimens (5x3mm) in 1mL of culture medium for 72 h. The extracts were then serially two-fold diluted and inserted into the cell-seeded wells for 24, 48 and 72 h. MTT assay was employed for analysis of cell viability. Cell supernatants were tested for nitric oxide using the Griess reagent system. MTA presented cytotoxic effect in undiluted extracts at 24 and 72 h. MTA Fillapex® presented the highest cytotoxic levels with important cell viability reduction for pure extracts and at ½ and ¼ dilutions. In this study, PC did not induce alterations in fibroblast viability. Nitric oxide was detected in extract-treated cell supernatants and also in the extracts only, suggesting presence of nitrite in the soluble content of the tested materials. In the present study, MTA Fillapex displayed the highest cytotoxic effect on periodontal ligament fibroblasts followed by white MTA and PC. PMID:23780362

Yoshino, Patrícia; Nishiyama, Celso Kenji; Modena, Karin Cristina da Silva; Santos, Carlos Ferreira; Sipert, Carla Renata

2013-01-01

54

Brain-Derived Neurotrophic Factor in Chronic Periodontitis  

OpenAIRE

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophic factor family. Outside the nervous system, BDNF has been shown to be expressed in various nonneural tissues, such as periodontal ligament, dental pulp, and odontoblasts. Although a role for BDNF in periodontal regeneration has been suggested, a function for BDNF in periodontal disease has not yet been studied. The aim of this study was to analyze the BDNF levels in periodontal tissues of patients with chronic periodontit...

Corre?a, Jo?ice Dias; Pereira, Daniele Sirineu; Madeira, Mila Fernandes Moreira; Queiroz-junior, Celso Martins; Souza, Danielle Glo?ria; Teixeira, Mauro Martins; Costa, Jose? Eusta?quio; Teixeira, Anto?nio Lu?cio; Da Silva, Tarci?lia Aparecida

2014-01-01

55

Cell proliferation and 3H-proline incorporation in periodontal ligament exposed to mechanical stress  

International Nuclear Information System (INIS)

In order to study the metabolic processes induced in the periodontal ligament by mechanical influences, a tension spring was implanted in rats between the incisor and the first maxillary molar on the right-hand side, while the left maxilla of these animals as well as non-operated rats served as controls. Under such mechanical stress, there occurred at 3, 10 and 21 days after implantation a significant increase in the 3H-thymidine labelling index, which was demonstrate histoautoradiographically. A change in cell density was not discovered. Therefore, the increase in S-phase fraction as equally recorded in both pressure and tension zones is regarded as an expression of an enhanced cell turnover. Cell renewal in the periodontal ligament can be modified by inflammatory processes within the gingival region. There is a slight enlargement of the periodontal space in the tension zone. Under experimental conditions, no change occurs in the silver grain number per cell after 3H-proline administration. The results indicate that, following the impact of orthodontic forces, the reactivity of periodontal cell proliferation as compared to collagen synthesis is enhanced. (author)

56

Influence of periodontal ligament simulation on bond strength and fracture resistance of roots restored with fiber posts  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Objective: Considering that periodontal ligament simulation may influence the stress distribution over teeth restored with intraradicular retainers, this study aimed to assess the combined effect of mechanical cycling and periodontal ligament simulation on both the bond strength between fiber posts [...] and root dentin and the fracture resistance of teeth restored using glass fiber posts. Material and Methods: Ninety roots were randomly distributed into 3 groups (n=10) (C-MC: control; P-MC: polyether; AS-MC: addition silicone) to test bond strength and 6 groups (n=10) (C: control; P: polyether; AS: addition silicone, without mechanical cycling, and C-MC, P-MC and AS-MC with mechanical cycling) to test fracture strength, according to the material used to simulate the periodontal ligament. For the bond strength test, fiber posts were cemented, cores were built, mechanical cycling was applied (2×106 cycles, 88 N, 2.2 Hz, and 45º incline), and the teeth cut into 3 slices (2 mm), which were then subjected to the push-out test at 1 mm/min. For the fracture strength test, fiber posts were cemented, cores were built, and half of the groups received mechanical cycling, followed by the compressive strength (45° to the long axis and 1 mm/min) performed on all groups. Results: Periodontal ligament simulation did not affect the bond strength (p=0.244) between post and dentin. Simulation of periodontal ligament (p=0.153) and application of mechanical cycling (p=0.97) did not affect fracture resistance. Conclusions: The materials used to simulate the periodontal ligament did not affect fracture or bond strength, therefore periodontal ligament simulation using the tested materials could be considered optional in the conditions of the study.

Ana Maria Estivalete, MARCHIONATTI; Vinícius Felipe, WANDSCHER; Juliana, BROCH; César Dalmolin, BERGOLI; Juliana, MAIER; Luiz Felipe, VALANDRO; Osvaldo Bazzan, KAIZER.

2014-10-01

57

Periodontal ligament and gingival fibroblasts participate in the production of TGF-?, interleukin (IL)-8 and IL-10  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The aim of this study was to quantify and compare the production of transforming growth factor beta (TGF-?), interleukin (IL)-8 and IL-10 by human cultured periodontal ligament and gingival fibroblasts both obtained from the same donors challenged with lipopolysaccharide (LPS) from Porphyromonas gin [...] givalis. Fibroblasts were exposed to 0.1-10 µg/mL of LPS from P. gingivalis and after 24 h the supernatants were collected and analyzed by enzyme-linked immunosorbent assay (ELISA). TGF-? protein production was upregulated in a concentration-dependent manner, mainly in gingival fibroblasts, which was statistically significant when challenged by 10 µg/mL LPS. Additionally, at this concentration, gingival fibroblasts had almost a two-fold increase in the amount of TGF-? when compared to periodontal ligament fibroblasts. Both periodontal ligament and gingival fibroblasts showed an increase in IL-8 production when challenged with 1 µg/mL and 10 µg/mL LPS. IL-10 production remained unaffected when challenged by any of the LPS concentrations tested in either periodontal ligament or gingival fibroblasts. Our results demonstrate that periodontal ligament and gingival fibroblasts when challenged by LPS from P. gingivalis with 24 h may play a critical role in producing TGF-? and IL-8 but not IL-10.

Ana Carolina de Faria, Morandini; Carla Renata, Sipert; Erivan Schnaider, Ramos-Junior; Daniel Thomas, Brozoski; Carlos Ferreira, Santos.

2011-04-01

58

Periodontal ligament, cementum, and alveolar bone in the oldest herbivorous tetrapods, and their evolutionary significance.  

Science.gov (United States)

Tooth implantation provides important phylogenetic and functional information about the dentitions of amniotes. Traditionally, only mammals and crocodilians have been considered truly thecodont, because their tooth roots are coated in layers of cementum for anchorage of the periodontal ligament, which is in turn attached to the bone lining the alveolus, the alveolar bone. The histological properties and developmental origins of these three periodontal tissues have been studied extensively in mammals and crocodilians, but the identities of the periodontal tissues in other amniotes remain poorly studied. Early work on dental histology of basal amniotes concluded that most possess a simplified tooth attachment in which the tooth root is ankylosed to a pedestal composed of "bone of attachment", which is in turn fused to the jaw. More recent studies have concluded that stereotypically thecodont tissues are also present in non-mammalian, non-crocodilian amniotes, but these studies were limited to crown groups or secondarily aquatic reptiles. As the sister group to Amniota, and the first tetrapods to exhibit dental occlusion, diadectids are the ideal candidates for studies of dental evolution among terrestrial vertebrates because they can be used to test hypotheses of development and homology in deep time. Our study of Permo-Carboniferous diadectid tetrapod teeth and dental tissues reveal the presence of two types of cementum, periodontal ligament, and alveolar bone, and therefore the earliest record of true thecodonty in a tetrapod. These discoveries in a stem amniote allow us to hypothesize that the ability to produce the tissues that characterize thecodonty in mammals and crocodilians is very ancient and plesiomorphic for Amniota. Consequently, all other forms of tooth implantation in crown amniotes are derived arrangements of one or more of these periodontal tissues and not simply ankylosis of teeth to the jaw by plesiomorphically retaining "bone of attachment", as previously suggested. PMID:24023957

LeBlanc, Aaron R H; Reisz, Robert R

2013-01-01

59

Advanced Glycation end Products Up-regulate the Endoplasmic Reticulum Stress in Human Periodontal Ligament Cells.  

Science.gov (United States)

Background: The accumulation of advanced glycation end products (AGEs) appears to be the main factors responsible for modulating periodontal inflammation in diabetes. The aim of the study is to examine the effects of AGEs on human periodontal ligament cells inflammation and to investigate the mechanism with a specific emphasis on the role of endoplasmic reticulum stress induced NF-?B pathway. Material and Methods: Cytotoxicity was measured by MTT assay. The protein expressions of endoplasmic reticulum markers and NF-?B were examined by western blot analysis. The translocation of NF-?B was observed by immunofluorescence assay. Pro-inflammatory chemokine production was determined by enzyme-linked immunosorbent assays. Results: Treatment with AGEs reduced cell viability in a concentration- and time- dependent manner. AGEs induced ER stress, as evidenced by survival molecules, such as glucose-regulated protein-78 (GRP78), double-stranded RNA-activated protein kinase-like endoplasmic reticulum kinase (PERK), and activating transcription factor 6 (ATF-6), and apoptotic molecules, such as CAAT/enhancer binding protein homologous protein (CHOP) and Caspase-12. AGEs upregulated the nucleoprotein expression of NF-?B, enhanced translocation of NF-?B from the cytoplasm to the nucleus, and increased the production of pro-inflammatory chemokine (IL-6 and IL-8). Conclusion: AGEs mediated human periodontal ligament cells inflammation via the endoplasmic reticulum stress-induced NF-?B pathway. PMID:25415248

Xu, Jie; Xiong, Ming; Huang, Bin; Chen, Huangqin

2014-11-21

60

Movement of fibroblasts in the periodontal ligament of the mouse incisor is related to eruption  

International Nuclear Information System (INIS)

Movement of fibroblasts in the periodontal ligament of the lower incisor of the mouse was studied by pulse-labeling with tritiated thymidine and proline. 3H-Thymidine was administered to mark the nuclei of the cells in the proliferative compartment near the basal end of the tooth; 3H-proline gave rise to a narrow band of radioactivity in the dentin, which served as a reference line for measurement of eruption. One or three weeks after injection in each animal, the lower right incisor was prevented from further eruption by being pinned to its alveolar process. The animals were killed 0, 1, or 2 weeks later, and their mandibles processed for LM-radioautography. It was found that in the left incisors, which were not inhibited in their eruption, labeled cells in the tooth-half of the periodontal ligament moved incisally at a rate similar to the eruption rate. In the pinned incisors, no further incisal migration could be established. It is concluded that fibroblast migration in the tooth-half of the ligament is strictly coupled to the eruptive process

61

Periodontal Plastic Surgery  

Science.gov (United States)

Periodontal plastic surgery is designed to restore form and function to the gum tissue, periodontal ligament, and the bone that ... with conservative behavioral changes and extending to periodontal plastic surgery. Treating Periodontal Disease Periodontal disease does not always ...

62

Effect of metronidazole and modulation of cytokine production on human periodontal ligament cells.  

Science.gov (United States)

Periodontitis is a multifactorial polymicrobial infection characterized by a destructive inflammatory process affecting tooth-supporting tissues and resulting in periodontal pocket formation, alveolar bone resorption and, eventually, tooth loss. The continuous challenge of host immune and resident cells by periodontopathogens and their virulence factors, such as lipopolysaccharide (LPS), results in enhanced and uncontrolled secretion of cytokines. The latter directly or indirectly participate in tissue destruction and bone resorption. Metronidazole (MTZ) is a widely used antimicrobial agent. The immunomodulatory effects of antibiotics might influence the degree of the local response to infection on the human periodontal ligament cell (HPLC). HPLCs play a role in the immune response of the oral cavity. In addition, HPLC can produce cytokines that increase the inflammatory response and that supply for normal communication. MTZ has also been proposed in the field of periodontal therapy either with a systemic administration or with local biodegradable sustained-release agents. The local administration of MTZ in the form of gel significantly reduces the systemic side effects. The aim of the present study, was to simulate the in vivo conditions occurring in diseased periodontal sites, and to evaluate the effects of MTZ on the viability of isolated HPLCs. The ability of MTZ to modulate the release of interleukin (IL)-1beta, IL-6, IL-8, IL-12 and tumor necrosis factor alpha (TNF-alpha) in HPLC, treated or not with LPS of Porphyromonas gingivalis was also evaluated. The results obtained showed that MTZ had no cytotoxic effect on HPLC and was able to inhibit the production of pro-inflammatory cytokines analyzed. The ability of MTZ to determine immunomodulatory effects could provide possible therapeutic applications in the field of periodontal research. PMID:20399284

Rizzo, Antonietta; Paolillo, Rossella; Guida, Luigi; Annunziata, Marco; Bevilacqua, Nazario; Tufano, Maria Antonietta

2010-07-01

63

Study of tension in the periodontal ligament using the finite elements method  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Orthodontic movement is process of transformation of a physical stimulation into a force applied to a tooth, with a biological response identified as bone remodelling. Although it is possible to measure the force applied on a tooth, its distribution around the root is irregular forming areas of high [...] er concentration of tensions, which do not correspond to the force initially applied. To evaluate the behavior of the periodontal ligament after the application of an external action and to prove which would be the areas of higher tension generated in the periodontium, the Finite Elements Method (FEM) was used in comparison to the results obtained in vivo on experimental models in rat. To test the error susceptibility of the technique used in the experimental model, the force application was simulated in three different heights on the mesial surface of the molar. The resulting histological analysis was compared with the result obtained for the computational code and disclosed that the greater focus of osteoclasts in activity had coincided with the compressed areas of the periodontal ligament. The alteration of points of force application generated areas of more extensive deformations in the periodontal ligament, as the point of application was more distant of the initial point, the horizontal force vector became bigger. These results demonstrate that the FEM is an adequate tool to study the distribution of orthodontic forces. The sensitivity of the experimental model used was also observed in relation to the installation of the dental movement device, which should be considered depending on the objective of the research.

Eliziane, Cossetin; Selma Hissae S. da, Nóbrega; Maria Goretti Freire de, Carvalho.

2012-02-01

64

Anti-inflammatory and antiosteoclastogenic activities of parthenolide on human periodontal ligament cells in vitro.  

Science.gov (United States)

Periodontitis is an inflammatory disease that causes osteolysis and tooth loss. It is known that the nuclear factor kappa B (NF-?B) signalling pathway plays a key role in the progression of inflammation and osteoclastogenesis in periodontitis. Parthenolide (PTL), a sesquiterpene lactone extracted from the shoots of Tanacetum parthenium, has been shown to possess anti-inflammatory properties in various diseases. In the study reported herein, we investigated the effects of PTL on the inflammatory and osteoclastogenic response of human periodontal ligament-derived cells (hPDLCs) and revealed the signalling pathways in this process. Our results showed that PTL decreased NF-?B activation, I-?B degradation, and ERK activation in hPDLCs. PTL significantly reduced the expression of inflammatory (IL-1?, IL-6, and TNF-?) and osteoclastogenic (RANKL, OPG, and M-CSF) genes in LPS-stimulated hPDLCs. In addition, PTL attenuated hPDLC-induced osteoclastogenic differentiation of macrophages (RAW264.7 cells), as well as reducing gene expression of osteoclast-related markers in RAW264.7 cells in an hPDLC-macrophage coculture model. Taken together, these results demonstrate the anti-inflammatory and antiosteoclastogenic activities of PTL in hPDLCs in vitro. These data offer fundamental evidence supporting the potential use of PTL in periodontitis treatment. PMID:25610476

Zhang, Xufang; Fan, Chen; Xiao, Yin; Mao, Xueli

2014-01-01

65

Establishment of immortalized periodontal ligament progenitor cell line and its behavioural analysis on smooth and rough titanium surface  

OpenAIRE

Periodontal ligament (PDL) can be obtained from patients undergoing orthodontic treatment. PDL contains progenitor cells that can be expanded and differentiated towards several mesenchymal lineages in vitro. Furthermore, PDL-derived cells have been shown to generate bone- and PDL-like structures in vivo. Thus, PDL cells, combined with suitable biomaterials, represent a promising tool for periodontitis-related research and PDL engineering.Here, a new PDL cell line using lentiviral gene transfe...

Docheva, D.; Padula, D.; Popov, C.; Weishaupt, P.; Pra?gert, M.; Miosge, N.; Hickel, R.; Bo?cker, W.; Clausen-schaumann, H.; Schieker, M.

2010-01-01

66

Impact of Nanotopography and/or Functional Groups on Periodontal Ligament Cell Growth  

Science.gov (United States)

The main purpose of this contribution was to obtain COOH functionalities and/or nanotopographic changes on the surface of 3D, non-woven polyester fabric (NWPF) discs (12.5 mm in diameter) by using low pressure water/O2 plasma assisted treatments. The prepared discs were characterized by various methods after the plasma treatment. Periodontal ligament (PDL) fibroblasts were used in cell culture studies. The cell culture results showed that plasma treated 3D NWPF discs are favorable for PDL cell spreading, growth and viability due to the presence of functional groups and/or the nanotopography of their surfaces.

?a?mazel, Hilal Türko?lu; Manolache, S.; Gümü?derel?o?lu, M.

67

Pulp revascularization of an immature permanent tooth with apical periodontitis: A case report  

OpenAIRE

The present case report analyzes the outcome of revascularization treatment of an immature permanent tooth with necrotic pulp and apical periodontitis. The canal was disinfected with copious irrigation and application of triple antibiotic paste. After the disinfection protocol was completed, apical bleeding was induced in the canal resulting in the formation of a blood clot. An absorbable scaffold was placed over it followed by an adequate triple coronal seal. After nine months follow-u...

Makkar Sameer; Kaler Nisha; Mann Navjot

2013-01-01

68

Osteoblast-like properties of human periodontal ligament cells: an in vitro analysis.  

Science.gov (United States)

Identifying the biological properties of the cells residing within the periodontal ligament (PDL) will help in understanding the role that these cells play in the various functions of the periodontal ligament, and will improve the success of clinical procedures such as orthodontic tooth movement. For this purpose, fibroblasts isolated from human periodontium were cultured and characterized both histochemically and biochemically with respect to their putative osteoblast-like properties. Histochemically, cultured PDL fibroblasts showed an intense staining for alkaline phosphatase (ALP). Biochemically, the basal ALP activity increased in culture over time. ALP levels after stimulation with 1 alpha, 25-dihydroxyvitamin D3 were significantly higher than those of control cultures. Moreover, immunofluorescence against osteocalcin (a highly reliable osteoblastic marker) was strongly positive. Von Kossa staining of the cell cultures revealed the formation of mineral-like nodules. These results indicate that human PDL fibroblasts exhibit in vitro phenotypic characteristics consistent with osteoblast-like cells, thus suggesting that such cells have the potential to differentiate into osteoblasts and/or cementoblasts. PMID:9458594

Basdra, E K; Komposch, G

1997-12-01

69

The Study of Dose- Response Mitogenic Effect of L-dopa on the Human Periodontal Ligament Fibroblasts Cells  

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Full Text Available Statement of Problem: Avulsion is one of the most serious emergencies in dental office.Avulsed teeth should be stored in a medium that supports the periodontal ligament cells viability. In some clinical situations, preserving media, contained growth factors and mitogenic products may be used for repair of traumatized (Periodontal Ligament tissues. It has been previously reported that levodopa (L-dopa accelerates healing by increasing the growth hormone level.Purpose: In this study, the local effect of L-dopa, on human periodontal ligament fibroblast (HPLF cells was evaluated.Materials and Methods: Samples were taken from impacted or semi-impacted third molar teeth, which didn’t show inflammatory reaction. The cells obtained from periodontal ligament of these teeth, were cultured in appropriate medium. The passage number between3-6 was taken for further experiments. The viability of HPLF cells, which treated, by Ldopa were evaluated by trypan blue dye exclusion and neutral red assay.Results: Results indicate that low concentration of L-dopa produces significant increase in number of these cells in comparison with control group. These results confirmed previous study about direct action of L-dopa on the viability of HPLF cells.Conclusion: On the basis of this study and previous reports, presence of L-dopa in preserving media may be useful in increasing the self-life transferring HPLF cells.

M. Zarabian

2004-09-01

70

In Vitro Cytotoxicity of White MTA, MTA Fillapex® and Portland Cement on Human Periodontal Ligament Fibroblasts  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Resumo O objetivo deste estudo foi comparar a citotoxicidade in vitro de agregado trióxido mineral (MTA) branco, MTA Fillapex® e cimento Portland (PC) em cultura de fibroblastos de ligamento periodontal humano. A cultura de fibroblastos de ligamento periodontal foi estabelecida e as célul [...] as foram utilizadas para os testes citotóxicos após a quarta passagem. A densidade celular foi ajustada em 1,25X10 4 células/poço em placas de 96 poços. Extratos dos materiais endodônticos foram preparados por meio da inserção de corpos de prova dos cimentos (5 X 3 mm) em 1 mL de meio de cultura durante 72 h. Os extratos foram diluídos serialmente na razão de ½ e inseridos aos poços contendo as células por 24, 48 e 72 h. Ensaio de MTT foi realizado para a avaliação da viabilidade celular. O sobrenadante das células foi testado em relação à presença de óxido nítrico utilizando o sistema de reagentes de Griess. O MTA apresentou efeito citotóxico quando o extrato era aplicado sem diluição durante 24 e 72 h. O MTA Fillapex apresentou os maiores níveis de citotoxicidade com importante redução da viabilidade celular quando o extrato foi aplicado puro e em diluições de ½ e ¼. Neste estudo, PC não induziu alterações na viabilidade de fibroblastos. Óxido nítrico foi detectado no sobrenadante de células tratadas com os extratos e ainda nos extratos somente, o que sugere a presença de nitrito no conteúdo solúvel dos materiais testados. No presente estudo, MTA Fillapex foi o material que demonstrou o maior efeito citotóxico sobre fibroblastos de ligamento periodontal seguido do MTA branco e do PC. Abstract in english The aim of this study was to compare the in vitro cytotoxicity of white mineral trioxide aggregate (MTA), MTA Fillapex® and Portland cement (PC) on human cultured periodontal ligament fibroblasts. Periodontal ligament fibroblast culture was established and the cells were used for cytotoxic tests aft [...] er the fourth passage. Cell density was set at 1.25 X10 4 cells/well in 96-well plates. Endodontic material extracts were prepared by placing sealer/cement specimens (5X3mm) in 1mL of culture medium for 72 h. The extracts were then serially two-fold diluted and inserted into the cell-seeded wells for 24, 48 and 72 h. MTT assay was employed for analysis of cell viability. Cell supernatants were tested for nitric oxide using the Griess reagent system. MTA presented cytotoxic effect in undiluted extracts at 24 and 72 h. MTA Fillapex® presented the highest cytotoxic levels with important cell viability reduction for pure extracts and at ½ and ¼ dilutions. In this study, PC did not induce alterations in fibroblast viability. Nitric oxide was detected in extract-treated cell supernatants and also in the extracts only, suggesting presence of nitrite in the soluble content of the tested materials. In the present study, MTA Fillapex displayed the highest cytotoxic effect on periodontal ligament fibroblasts followed by white MTA and PC.

Patrícia, Yoshino; Celso Kenji, Nishiyama; Karin Cristina da Silva, Modena; Carlos Ferreira, Santos; Carla Renata, Sipert.

2013-04-01

71

Modificações no periodonto de ratos diabéticos após a movimentação ortodôntica Periodontal ligament changes after induced dental movement in diabetic rats  

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Full Text Available OBJETIVOS: o objetivo deste trabalho foi avaliar as modificações do ligamento periodontal de incisivos de ratos diabéticos submetidos a forças ortodônticas. MÉTODOS: vinte ratos machos Wistar (Rattus norvegicus com 105 dias de idade foram empregados. Os ratos foram divididos em quatro grupos: C - animais normoglicêmicos não submetidos à movimentação dentária; CAO - animais normoglicêmicos submetidos à movimentação dentária; D - animais diabéticos não submetidos à movimentação dentária; DAO - animais diabéticos submetidos à movimentação dentária. Os animais permaneceram com o dispositivo de movimentação dentária por 5 dias. Foram avaliados o número de vasos sangüíneos e a espessura do ligamento periodontal nos terços cervical, médio e apical dos cortes histológicos. RESULTADOS E CONCLUSÕES: no lado de tensão, a movimentação dentária nos animais do grupo CAO resultou em um ligamento periodontal mais espesso (17,64% no terço apical, 39,28% no terço médio e 51,35% na região cervical, quando comparado ao grupo C (p 0,05. Ainda no lado de tensão, foram observadas lacunas de reabsorção nos animais dos grupos CAO, D e DAO. O lado de pressão não foi examinado nesta fase do estudo.AIM: The aim of this study was to evaluate the periodontal ligament changes after induced dental movement of the upper incisor in diabetic rats. METHODS: Twenty Wistar rats (Rattus norvegicus with 105 days of age were used. The rats were divided in four groups: C - normoglicemic animals not submitted to dental movement; CAO - normoglicemic animals submitted to dental movement; D - diabetic animals not submitted the dental movement; DAO - diabetic animals submitted to dental movement. The animals had remained with dental movement devices during 5 days. The number of sanguine vessels and the thickness of the periodontal ligament were evaluated at cervical, medium and apical histological cut regions. RESULTS AND CONCLUSION: At tension side, the dental movement in the animals of group CAO resulted in a thicker periodontal ligament (17.64% apical, 39.28% medium, 51.35% cervical when compared to C group (p < 0.05 for medium and cervical area. Group DAO exhibited an increase of periodontal ligament thickness of 50.55% (apical, 48.14% (average and 50% (cervical when compared to group D (p < 0.05. The periodontal ligament sanguine vessels number did not differed significantly for all groups (p < 0.05. At tension side, bone reabsorption lacunae were observed in CAO, D and DAO groups. The pressure side was not examined in this study phase.

Luis Alberto Sabino Vila Real

2009-02-01

72

Electrospun fibrous scaffolds combined with nanoscale hydroxyapatite induce osteogenic differentiation of human periodontal ligament cells  

Science.gov (United States)

Periodontal repair is a complex process in which regeneration of alveolar bone is a vital component. The aim of this study was to develop a biodegradable scaffold with good biocompatibility and osteoinductive ability. Two types of composite fibrous scaffolds were produced by electrospinning, ie, type I collagen/poly(?-caprolactone) (COL/PCL) and type I collagen/poly(?-caprolactone)/nanoscale hydroxyapatite (COL/PCL/nHA) with an average fiber diameter of about 377 nm. After a simulated body fluid (SBF) immersion test, the COL/PCL/nHA-SBF scaffold developed a rough surface because of the calcium phosphate deposited on the fibers, suggesting that the presence of nHA promoted the mineralization potential of the scaffold. Energy dispersive X-ray spectroscopy clearly showed the calcium and phosphorus content in the COL/PCL/nHA and COL/PCL/nHA-SBF scaffolds, confirming the findings of nHA and calcium phosphate precipitation on scanning electron micrographs. Water contact analysis revealed that nHA could improve the hydrophilic nature of the COL/PCL/nHA-SBF scaffold. The morphology of periodontal ligament cells cultured on COL/PCL-SBF and COL/PCL/nHA-SBF was evaluated by scanning electron microscopy. The results showed that cells adhered to either type of scaffold and were slightly spindle-shaped in the beginning, then extended gradually with stretched filopodia, indicating an ability to fill the fiber pores. A Cell Counting Kit-8 assay showed that both scaffolds supported cell proliferation. However, real-time quantitative polymerase chain reaction analysis showed that expression of the bone-related markers, alkaline phosphatase and osteocalcin, was upregulated only on the COL/PCL/nHA-SBF scaffold, indicating that this scaffold had the ability to induce osteogenic differentiation of periodontal ligament cells. In this study, COL/PCL/nHA-SBF produced by electrospinning followed by biomimetic mineralization had combined electrospun fibers with nHA in it. This scaffold has good biocompatibility and osteoinductive ability as a result of the characteristics of nHA, so could be innovatively applied to periodontal tissue engineering as a potential scaffold. PMID:25206304

Wu, Xiaonan; Miao, Leiying; Yao, Yingfang; Wu, Wenlei; Liu, Yu; Chen, Xiaofeng; Sun, Weibin

2014-01-01

73

Application of the iodide clearance technique to monitor local changes in periodontal ligament blood flow  

International Nuclear Information System (INIS)

The present study was undertaken to validate a newly developed technique for monitoring blood flow changes with local clearance of 125I in the periodontal ligament (PDL). The tracer substance was allowed to diffuse into the intact PDL via a cavity that was drilled from the root canal out towards the root surface. Electric stimulation of the cervical sympathetic trunk caused a reduction in the clearance rate of the tracer from the cavity in a frequency-dependent manner. Intra-arterial infusions of noradrenaline also induced decreases in clearance rate. Intra-arterial infusions of the vasodilators substance P and vasoactive intestinal peptide induced increases in clearance rate. The present technique makes it possible to monitor local blood flow changes in the intact PDL during both decreases and increases in blood flow

74

Pulp revascularization of an immature permanent tooth with apical periodontitis: A case report  

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Full Text Available The present case report analyzes the outcome of revascularization treatment of an immature permanent tooth with necrotic pulp and apical periodontitis. The canal was disinfected with copious irrigation and application of triple antibiotic paste. After the disinfection protocol was completed, apical bleeding was induced in the canal resulting in the formation of a blood clot. An absorbable scaffold was placed over it followed by an adequate triple coronal seal. After nine months follow-up, increased thickening of dentinal walls with intact lamina dura and complete apical closure was reported radiographically. Therefore, revascularization therapy could be recommended as an alternative treatment option.

Makkar Sameer

2013-01-01

75

Electrospun fibrous scaffolds combined with nanoscale hydroxyapatite induce osteogenic differentiation of human periodontal ligament cells  

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Full Text Available Xiaonan Wu,1 Leiying Miao,2,# Yingfang Yao,3 Wenlei Wu,1 Yu Liu,1 Xiaofeng Chen,1 Weibin Sun1,# 1Department of Periodontology, Hospital of Stomatology, Medical School of Nanjing University, Nanjing, People’s Republic of China; 2Department of Cariology and Endodontics, Hospital of Stomatology, Medical School of Nanjing University, Nanjing, People’s Republic of China; 3Eco-materials and Renewable Energy Research Center, Department of Materials Science and Engineering, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing, People’s Republic of China #These authors contributed equally to this work Abstract: Periodontal repair is a complex process in which regeneration of alveolar bone is a vital component. The aim of this study was to develop a biodegradable scaffold with good biocompatibility and osteoinductive ability. Two types of composite fibrous scaffolds were produced by electrospinning, ie, type I collagen/poly(?-caprolactone (COL/PCL and type I collagen/poly(?-caprolactone/nanoscale hydroxyapatite (COL/PCL/nHA with an average fiber diameter of about 377 nm. After a simulated body fluid (SBF immersion test, the COL/PCL/nHA-SBF scaffold developed a rough surface because of the calcium phosphate deposited on the fibers, suggesting that the presence of nHA promoted the mineralization potential of the scaffold. Energy dispersive X-ray spectroscopy clearly showed the calcium and phosphorus content in the COL/PCL/nHA and COL/PCL/nHA-SBF scaffolds, confirming the findings of nHA and calcium phosphate precipitation on scanning electron micrographs. Water contact analysis revealed that nHA could improve the hydrophilic nature of the COL/PCL/nHA-SBF scaffold. The morphology of periodontal ligament cells cultured on COL/PCL-SBF and COL/PCL/nHA-SBF was evaluated by scanning electron microscopy. The results showed that cells adhered to either type of scaffold and were slightly spindle-shaped in the beginning, then extended gradually with stretched filopodia, indicating an ability to fill the fiber pores. A Cell Counting Kit-8 assay showed that both scaffolds supported cell proliferation. However, real-time quantitative polymerase chain reaction analysis showed that expression of the bone-related markers, alkaline phosphatase and osteocalcin, was upregulated only on the COL/PCL/nHA-SBF scaffold, indicating that this scaffold had the ability to induce osteogenic differentiation of periodontal ligament cells. In this study, COL/PCL/nHA-SBF produced by electrospinning followed by biomimetic mineralization had combined electrospun fibers with nHA in it. This scaffold has good biocompatibility and osteoinductive ability as a result of the characteristics of nHA, so could be innovatively applied to periodontal tissue engineering as a potential scaffold. Keywords: nanoscale hydroxyapatite, electrospinning, periodontal ligament cells 

Wu XN

2014-08-01

76

Appropriateness of viscoelastic soft materials as in vitro simulators of the periodontal ligament.  

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The periodontal ligament is a viscoelastic soft tissue that connects the tooth to the alveolar bone. This tissue should be simulated in numerical as well as in laboratory models. The mechanical properties of this tissue were previously determined ex vivo and in vivo. The aim of the study was to analyse the appropriateness of impression and reline materials used in dentistry to simulate viscoelastic behaviour of the periodontal ligament. Two reline [Durabase (Reliance Dental MFG, Co.) and Soft Liner (GC Corporation)] and two impression [President Plus (Coltene) and Prestige L (Vanini Dental Industry)] materials were examined in recovery and tensile relaxation tests. Recovery: This experiment simulated in vivo test. Roots of a pair of plastic maxillary premolar teeth were covered with each test material and embedded in acryl while maintaining the contact point. A 0·1-mm stainless steel strip, inserted at the contact point and maintained for 10 s, was used to tip the teeth. After removal, the tightness of dental contact point was measured over 30 min by determining the force needed to insert a 0·05-mm metal strip. Tensile relaxation: strips were elongated to 120%, 140% and 160% of their initial length and maintained at that length for 30 min. Two-phase decay function was applied. The results showed that elastic modulus and relaxation behaviour were significantly different between materials. Elastic modulus values were in the same range of those reported in the literature. However, the recovery values and behaviour showed that impression materials, especially President, are the materials of choice for this purpose because they simulated better the in vivo test. PMID:21707697

Brosh, T; Porat, N; Vardimon, A D; Pilo, R

2011-12-01

77

In vitro viability of human periodontal ligament cells in green tea extract  

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Context: Delayed replantation of avulsed teeth may be successful if the majority of periodontal ligament cells (PDL) survive. A proper transport medium is required when immediate replantation is not possible. Green tea extract (GTE) may be effective in preserving the cells because of its special properties. Aims: This study was done to evaluate the potential of GTE in periodontal ligament cells preservation. Materials and Methods: Fifty-four extracted human teeth with closed apices were randomly divided into three groups each with 18 teeth as follow: GTE, water (negative control), and Hank's balanced salt solution (HBSS) (positive control). The specimens were immersed in the media for 1, 3, and 15 hours at 4°C (n = 6) and treated with collagenase 1A for 45 minutes. Cell viability was determined using the trypan blue exclusion technique. Statistical Analysis: Data were analyzed by one-way analysis of variance (ANOVA), post hoc Tukey and paired t-test at significance level of P < 0.05. Results: Means (standard deviation, SD) of viable cells in HBSS, water, and GTE were estimated 348.33 ± 88.49, 101 ± 14.18, and 310.56 ± 56.97 at 1 hours; 273.4 ± 44.80, 64.16 ± 16.44, and 310.2 ± 11.21 at 3 hours; and 373.72 ± 67.81, 14.41 ± 2.88 and 315.24 ± 34.48 at 15 hours; respectively. No significant differences were found between HBSS and GTE at all the time intervals. Both these solutions could preserve the cells more than water significantly. Conclusion: GTE and HBSS were equally effective in preserving the cells and were significantly superior to water.

Ghasempour, Maryam; Moghadamnia, Ali Akbar; Abedian, Zeynab; Amir, Mahdi Pour; Feizi, Farideh; Gharekhani, Samane

2015-01-01

78

Force-induced Adrb2 in periodontal ligament cells promotes tooth movement.  

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The sympathetic nervous system (SNS) regulates bone resorption through ?-2 adrenergic receptor (Adrb2). In orthodontic tooth movement (OTM), mechanical force induces and regulates alveolar bone remodeling. Compressive force-associated osteoclast differentiation and alveolar bone resorption are the rate-limiting steps of tooth movement. However, whether mechanical force can activate Adrb2 and thus contribute to OTM remains unknown. In this study, orthodontic nickel-titanium springs were applied to the upper first molars of rats and Adrb1/2(-/-) mice to confirm the role of SNS and Adrb2 in OTM. The results showed that blockage of SNS activity in the jawbones of rats by means of superior cervical ganglion ectomy reduced OTM distance from 860 to 540 ?m after 14 d of force application. In addition, the injection of nonselective Adrb2 agonist isoproterenol activated the downstream signaling of SNS to accelerate OTM from 300 to 540 ?m after 7 d of force application. Adrb1/2(-/-) mice showed significantly reduced OTM distance (19.5 ?m) compared with the wild-type mice (107.6 ?m) after 7 d of force application. Histopathologic analysis showed that the number of Adrb2-positive cells increased in the compressive region of periodontal ligament after orthodontic force was applied on rats. Mechanistically, mechanical compressive force upregulated Adrb2 expression in primary-cultured human periodontal ligament cells (PDLCs) through the elevation of intracellular Ca(2+) concentration. Activation of Adrb2 in PDLCs increased the RANKL/OPG ratio and promoted the peripheral blood mononuclear cell differentiation to osteoclasts in the cocultured system. Upregulation of Adrb2 in PDLCs promoted osteoclastogenesis, which accelerated OTM through Adrb2-enhanced bone resorption. In summary, this study suggests that mechanical force-induced Adrb2 activation in PDLCs contributes to SNS-regulated OTM. PMID:25252876

Cao, H; Kou, X; Yang, R; Liu, D; Wang, X; Song, Y; Feng, L; He, D; Gan, Y; Zhou, Y

2014-11-01

79

Effects of Continuous and Interrupted Forces on Gene Transcription in Periodontal Ligament Cells in Vitro  

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Full Text Available The biological mechanisms of tooth movement are based on the response of periodontal tissues to mechanical forces. The final result of these responses is remodeling of the extracellular matrix. Tissue reactions may vary depending upon the type, magnitude and duration of the applied forces. The purpose of the present study was to analyze the effects of centrifugal force on the transcription of collagen type-I (Col-I, matrix metalloproteinase-1 (MMP-1, and tissue inhibitor of metalloproteinase- 1 (TIMP-1 genes in human periodontal ligament (PDL fibroblasts. Human fibroblasts obtained from the PDL were cultured and subjected to centrifugal forces (36.3 g/cm2 for 30, 60 and 90 min continuously. This was also carried out interruptedly, three times for 30 min and six times for 15 min. The mRNAs encoding for Col-I, MMP-1, and TIMP-1 were quantified using RT-PCR. The mRNA levels of Col-I and MMP-1 were increased when continuous force was applied for 30 min and 60 min respectively. The interrupted force had almost no effect on Col-I, MMP-1 and TIMP-1 genes. These results indicate that continuous forces may have a greater effect in inducing gene expression during the remodeling process of PDL compared to interrupted forces with short rest periods.

Seyed Nasser Ostad

2011-10-01

80

Cigarette smoking hinders human periodontal ligament-derived stem cell proliferation, migration and differentiation potentials.  

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Cigarette smoking contributes to the development of destructive periodontal diseases and delays its healing process. Our previous study demonstrated that nicotine, a major constituent in the cigarette smoke, inhibits the regenerative potentials of human periodontal ligament-derived stem cells (PDLSC) through microRNA (miRNA) regulation. In this study, we hypothesized that the delayed healing in cigarette smokers is caused by the afflicted regenerative potential of smoker PDLSC. We cultured PDLSC from teeth extracted from smokers and non-smokers. In smoker PDLSC, we found significantly reduced proliferation rate and retarded migration capabilities. Moreover, alkaline phosphatase activity, calcium deposition and acidic polysaccharide staining were reduced after BMP2-induced differentiation. In contrast, more lipid deposition was observed in adipogenic-induced smoker PDLSC. Furthermore, two nicotine-related miRNAs, hsa-miR-1305 (22.08 folds, p = 0.040) and hsa-miR-18b (15.56 folds, p = 0.018), were significantly upregulated in smoker PDLSC, suggesting these miRNAs might play an important role in the deteriorative effects on stem cells by cigarette smoke. Results of this study provide further evidences that cigarette smoking affects the regenerative potentials of human adult stem cells. PMID:25591783

Ng, Tsz Kin; Huang, Li; Cao, Di; Yip, Yolanda Wong-Ying; Tsang, Wai Ming; Yam, Gary Hin-Fai; Pang, Chi Pui; Cheung, Herman S

2015-01-01

81

Immunohistochemical Localization of Versican, Link Protein and Hyaluronic Acid Binding Protein in the Human Periodontal Ligament  

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Full Text Available The purpose of the present study was to histopathologically and immunohistochemically investigate the distribution of proteoglycans in human periodontal ligament (PDL. Specimens from osteotomy and tooth extraction having healthy PDL were studied. Histologically, PDL consisted of fibrous tissues, involving a compact arrangement area and edematous or myxoid area. Immuno-histochemically, versican binding region (12C5, versican link protein (8A4 and biotinylated hyaluronic acid binding protein (B-HABP were distributed in PDL. In addition, positive immunore-activity for 12C5 and 8A4 was stronger in the compact arrangement area than in the edematous or myxoid area. Reactivity for B-HABP was stronger in the edematous or myxoid area than in the compact fibrous area. These results suggest that versican and link protein are associated with fibrous tissues, whereas hyaluronic acid is related to the formation of edematous and/or myxoid tissue in human PDL. These substances may play a role in periodontal homeostasis by protecting against mechanical stress.

Tadahiko Utsunomiya

2014-08-01

82

[Stress distribution in the periodontal ligament induced by orthodontic forces. Use of finite-element method].  

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This study was designed to investigate the stress levels induced in the periodontal tissue by orthodontic forces using the three-dimensional finite element method. The three-dimensional finite element model of the lower first premolar was constructed on the basis of average anatomic morphology and consisted of 240 isoparametric elements. Principal stresses were determined at the root, alveolar bone, and periodontal ligament (PDL). In all loading cases for the buccolingually directed forces, three principal stresses in the PDL were very similar. At the surface of the root and the alveolar bone, large bending stresses acting almost parallel to the root were generally observed. During tipping movement, stresses nonuniformly varied with a large difference from the cervix to the apex of the root. On the other hand, in case of movement approaching translation, the stresses induced were either tensile or compressive at all occlusogingival levels with some difference of the stress from the cervix to the apex. The pattern and magnitude of stresses in the periodontium from a given magnitude of force were markedly different, depending on the center of rotation of the tooth. PMID:2639866

Tanne, K; Bantleon, H P

1989-01-01

83

Assessment of an efficient xeno-free culture system of human periodontal ligament stem cells.  

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The possibility of transplanting adult stem cells into damaged organs has opened new prospects for the treatment of several human pathologies. The purpose of this study was to develop a culture system for the expansion and production of human Periodontal Ligament Stem Cells (hPDLSCs) using a new xeno-free media formulation and ensuring the maintenance of the stem cells features comprising the multiple passage expansion, mesengenic lineage differentiation, cellular phenotype, and genomic stability, essential elements for conforming to translation to cell therapy. Somatic stem cells were isolated from the human periodontium using a minimally invasive periodontal access flap surgery in healthy donors. Expanded hPDLSCs in a xeno-free culture showed the morphological features of stem cells, expressed the markers associated with pluripotency, and a normal karyotype. Under appropriate culture conditions, hPDLSCs presented adipogenic and osteogenic potential; indeed, a very high accumulation of lipid droplets was evident in the cytoplasm of adipogenic-induced cells, and indisputable evidence of osteogenic differentiation, investigated by transmission electron microscopy, and analyzed for gene expression analysis has been shown. Based on these data, the novel xeno-free culture method might provide the basis for Good Manufacturing Procedure culture of autologous stem cells, readily accessible from human periodontium, and can be a resource to facilitate their use in human clinical studies for potential therapeutic regeneration. PMID:24787358

Trubiani, Oriana; Piattelli, Adriano; Gatta, Valentina; Marchisio, Marco; Diomede, Francesca; D'Aurora, Marco; Merciaro, Ilaria; Pierdomenico, Laura; Maraldi, Nadir Mario; Zini, Nicoletta

2015-01-01

84

Finite element simulation of the behavior of the periodontal ligament: a validated nonlinear contact model.  

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Due to its significance in tooth movement, the stress/deformation field of periodontium and the alveolar bone remodeling process, periodontal ligament (PDL) cannot be excluded from the studies investigating dental biomechanics regarding its excessive deformability. Therefore, many analytical and numerical researches are carried out to simulate its response and to create a constitutive model via experiments intending to discover the material properties of PDL. The aim of this study is to formulate a user specified contact model that can be used in conjunction with finite element (FE) software and reflects PDL's influence on neighboring structures based on the currently available information, without requiring an actual volumetric finite element mesh of ligament. The results show good agreement with available experimental tooth mobility data. Smooth stress fields are obtained on the tooth root and alveolar bone, which is a significant aspect in bone-remodeling studies. The advantage of simulating PDL as a contact model at the interface of tooth root and the alveolar process instead of a solid-meshed FE model with poor geometric morphology and/or very dense mesh is expected to save pre/post-processing workforce, to increase the accuracy and to contribute to the smoothness of interface stress distributions. PMID:25110168

Tuna, Meral; Sunbuloglu, Emin; Bozdag, Ergun

2014-09-22

85

Low-intensity pulsed ultrasound stimulation facilitates osteogenic differentiation of human periodontal ligament cells.  

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Human periodontal ligament cells (hPDLCs) possess stem cell properties, which play a key role in periodontal regeneration. Physical stimulation at appropriate intensities such as low-intensity pulsed ultrasound (LIPUS) enhances cell proliferation and osteogenic differentiation of mesechymal stem cells. However, the impacts of LIPUS on osteogenic differentiation of hPDLCs in vitro and its molecular mechanism are unknown. This study was undertaken to investigate the effects of LIPUS on osteogenic differentiation of hPDLCs. HPDLCs were isolated from premolars of adolescents for orthodontic reasons, and exposed to LIPUS at different intensities to determine an optimal LIPUS treatment dosage. Dynamic changes of alkaline phosphatase (ALP) activities in the cultured cells and supernatants, and osteocalcin production in the supernatants after treatment were analyzed. Runx2 and integrin ?1 mRNA levels were assessed by reverse transcription polymerase chain reaction analysis after LIPUS stimulation. Blocking antibody against integrin?1 was used to assess the effects of integrin?1 inhibitor on LIPUS-induced ALP activity, osteocalcin production as well as calcium deposition. Our data showed that LIPUS at the intensity of 90 mW/cm2 with 20 min/day was more effective. The ALP activities in lysates and supernatants of LIPUS-treated cells started to increase at days 3 and 7, respectively, and peaked at day 11. LIPUS treatment significantly augmented the production of osteocalcin after day 5. LIPUS caused a significant increase in the mRNA expression of Runx2 and integrin ?1, while a significant decline when the integrin?1 inhibitor was used. Moreover, ALP activity, osteocalcin production as well as calcium nodules of cells treated with both daily LIPUS stimulation and integrin?1 antibody were less than those in the LIPUS-treated group. In conclusion, LIPUS promotes osteogenic differentiation of hPDLCs, which is associated with upregulation of Runx2 and integrin ?1, which may thus provide therapeutic benefits in periodontal tissue regeneration. PMID:24743551

Hu, Bo; Zhang, Yuanyuan; Zhou, Jie; Li, Jing; Deng, Feng; Wang, Zhibiao; Song, Jinlin

2014-01-01

86

Enhanced compatibility of chemically modified titanium surface with periodontal ligament cells  

International Nuclear Information System (INIS)

Highlights: ? Cell-adhesive molecules were covalently immobilized on a Ti surface. ? Immobilized cell-adhesive molecules maintained native function on the Ti surface. ? Immobilized collagen enhanced adhesion of periodontal ligament cells to the Ti. - Abstract: A simple chemical modification method was developed to immobilize cell-adhesive molecules on a titanium surface to improve its compatibility with human periodontal ligament cells (HPDLCs).The polished titanium disk was immersed in 1% (v/v) p-vinylbenzoic acid solution for 2 h to introduce carboxyl groups onto the surface. After rinsing with distilled deionized water, the titanium disk was dipped into 1.47% 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide solution containing 0.1 mg/ml Gly-Arg-Gly-Asp-Ser (GRGDS), human plasma fibronectin (pFN), or type I collagen from calf skin (Col) to covalently immobilize the cell-adhesive molecules on the titanium surface via formation of peptide bonds. X-ray photoelectron spectroscopy analyses revealed that cell-adhesive molecules were successfully immobilized on the titanium surfaces. The Col-immobilized titanium surface revealed higher values regarding nano rough characteristics than the as-polished titanium surface under scanning probe microscopy. The number of HPDLCs attached to both the pFN- and Col-immobilized titanium surfaces was twice that attached to the as-polished titanium surfaces. The cells were larger with the cellular processes that stretched to a greaterrocesses that stretched to a greater extent on the pFN- and Col-immobilized titanium surfaces than on the as-polished titanium surface (p < 0.05). HPDLCs on the Col-immobilized titanium surfaces showed more extensive expression of vinculin at the tips of cell projections and more contiguously along the cell outline than on the as-polished, GRGDS-immobilized and pFN-immobilized titanium surfaces. It was concluded that cell-adhesive molecules successfully immobilized on the titanium surface and improved the compatibility of the surface with HPDLCs. The Col-immobilized titanium surface could be used for forming ligament-like tissues around titanium dental implants.

87

"THE STUDY OF DOSE-RESPONSE MITOGENIC EFFECT OF L-DOPA ON THE HUMAN PERIODONTAL LIGAMENT FIBROBLAST CELLS"  

OpenAIRE

Avulsion is one of the most serious emergencies in dental office. In the event of any problem, the tooth should be stored in a medium that supports the periodontal ligament cell viability. In other clinical situations, preserving media, growth factors and mitogenic products may be useful in repairing the traumatized tissues. It has been previously reported that levodopa (L-dopa) accelerates healing by increasing the growth hormone level. In this study, the local effect of L-dopa, as a mitogen...

Zarabian, M.; Ostad, F. Salehipour S. N.

2004-01-01

88

Effect of the simulated periodontal ligament on cast post-and-core removal using an ultrasonic device  

OpenAIRE

ABSTRACT OBJECTIVE: The aim of this study was to evaluate the effect of simulated periodontal ligament (SPDL) on custom cast dowel and core removal by ultrasonic vibration. MATERIAL AND METHODS: Thirty-two human maxillary canines were included in resin cylinders with or without SPDL made from polyether impression material. In order to allow tensile testing, the roots included in resin cylinders with SPDL were fixed to cylinders with two stainless steel wires. Post-holes were prepared by stand...

Manoel Brito-Junior; Neilor Mateus Antunes Braga; Danilo Costa Rodrigues; Carla Cristina Camilo; André Luis Faria-e-Silva

2010-01-01

89

Differential Expression of Osteo-Modulatory Molecules in Periodontal Ligament Stem Cells in Response to Modified Titanium Surfaces  

OpenAIRE

This study assessed differential gene expression of signaling molecules involved in osteogenic differentiation of periodontal ligament stem cells (PDLSCs) subjected to different titanium (Ti) surface types. PDLSCs were cultured on tissue culture polystyrene (TCPS), and four types of Ti discs (PT, SLA, hydrophilic PT (pmodPT), and hydrophilic SLA (modSLA)) with no osteoinductive factor and then osteogenic activity, including alkaline phosphatase (ALP) activity, mRNA expression of runt-related ...

So Yeon Kim; Ji-Yeon Yoo; Joo-Young Ohe; Jung-Woo Lee; Ji-Hoi Moon; Yong-Dae Kwon; Jung Sun Heo

2014-01-01

90

Strontium-containing mesoporous bioactive glass scaffolds with improved osteogenic/cementogenic differentiation of periodontal ligament cells for periodontal tissue engineering.  

Science.gov (United States)

To achieve the ultimate goal of periodontal tissue engineering, it is of great importance to develop bioactive scaffolds which can stimulate the osteogenic/cementogenic differentiation of periodontal ligament cells (PDLCs) for the favorable regeneration of alveolar bone, root cementum and periodontal ligament. Strontium (Sr) and Sr-containing biomaterials have been found to induce osteoblast activity. However, there has been no systematic report about the interaction between Sr or Sr-containing biomaterials and PDLCs for periodontal tissue engineering. The aims of this study were to prepare Sr-containing mesoporous bioactive glass (Sr-MBG) scaffolds and investigate whether the addition of Sr could stimulate osteogenic/cementogenic differentiation of PDLCs in a tissue-engineering scaffold system. The composition, microstructure and mesopore properties (specific surface area, nanopore volume and nanopore distribution) of Sr-MBG scaffolds were characterized. The proliferation, alkaline phosphatase (ALP) activity and osteogenesis/cementogenesis-related gene expression (ALP, Runx2, Col I, OPN and CEMP1) of PDLCs on different kinds of Sr-MBG scaffolds were systematically investigated. The results show that Sr plays an important role in influencing the mesoporous structure of MBG scaffolds in which high contents of Sr decreased the well-ordered mesopores as well as their surface area/pore volume. Sr(2+) ions could be released from Sr-MBG scaffolds in a controlled way. The incorporation of Sr into MBG scaffolds has significantly stimulated ALP activity and osteogenesis/cementogenesis-related gene expression of PDLCs. Furthermore, Sr-MBG scaffolds in a simulated body fluid environment still maintained excellent apatite-mineralization ability. The study suggests that the incorporation of Sr into MBG scaffolds is a viable way to stimulate the biological response of PDLCs. Sr-MBG scaffolds are a promising bioactive material for periodontal tissue-engineering applications. PMID:22750735

Wu, Chengtie; Zhou, Yinghong; Lin, Chucheng; Chang, Jiang; Xiao, Yin

2012-10-01

91

Porphyromonas gingivalis GroEL Induces Osteoclastogenesis of Periodontal Ligament Cells and Enhances Alveolar Bone Resorption in Rats  

Science.gov (United States)

Porphyromonas gingivalis is a major periodontal pathogen that contains a variety of virulence factors. The antibody titer to P. gingivalis GroEL, a homologue of HSP60, is significantly higher in periodontitis patients than in healthy control subjects, suggesting that P. gingivalis GroEL is a potential stimulator of periodontal disease. However, the specific role of GroEL in periodontal disease remains unclear. Here, we investigated the effect of P. gingivalis GroEL on human periodontal ligament (PDL) cells in vitro, as well as its effect on alveolar bone resorption in rats in vivo. First, we found that stimulation of PDL cells with recombinant GroEL increased the secretion of the bone resorption-associated cytokines interleukin (IL)-6 and IL-8, potentially via NF-?B activation. Furthermore, GroEL could effectively stimulate PDL cell migration, possibly through activation of integrin ?1 and ?2 mRNA expression as well as cytoskeletal reorganization. Additionally, GroEL may be involved in osteoclastogenesis via receptor activator of nuclear factor ?-B ligand (RANKL) activation and alkaline phosphatase (ALP) mRNA inhibition in PDL cells. Finally, we inoculated GroEL into rat gingiva, and the results of microcomputed tomography (micro-CT) and histomorphometric assays indicated that the administration of GroEL significantly increased inflammation and bone loss. In conclusion, P. gingivalis GroEL may act as a potent virulence factor, contributing to osteoclastogenesis of PDL cells and resulting in periodontal disease with alveolar bone resorption. PMID:25058444

Lin, Feng-Yen; Hsiao, Fung-Ping; Huang, Chun-Yao; Shih, Chun-Ming; Tsao, Nai-Wen; Tsai, Chien-Sung; Yang, Shue-Fen; Chang, Nen-Chung; Hung, Shan-Ling; Lin, Yi-Wen

2014-01-01

92

An electron microscopic radioautographic study of collagen secretion in periodontal ligament fibroblasts of the mouse: I. Normal fibroblasts  

International Nuclear Information System (INIS)

Analysis of electron microscopic radioautographs revealed a maximum labeling with 3H-proline of rough endoplasmic reticulum (RER) at 3 minutes, Golgi saccules 1 and 2 at 10 minutes, Golgi saccules type 3 at 20 minutes, and presecretory and secretory granules at 30 minutes. Labeling of the extra-cellular collagen matrix occurred at 30 minutes and increased with time. These observations suggest that pro-a-chains of collagen in periodontal ligament fibroblasts are synthesized in the RER and transported to the Golgi apparatus within 10 minutes. These chains then undergo parallel alignment in Golgi saccules type 2 and form segment-long-spacing-like crystallites in Golgi saccules type 3 between 10 and 20 minutes. The peak labeling of presecretory granules and mature secretory granules in small amounts at 30 minutes and the rapid increase in labeling of extracellular collagen matrix which begins at 30 minutes, indicates that the formation of secretory granules requires approximately 30 minutes and that a rapid system of secretory granule translocation exists in periodontal ligament fibroblasts. This evidence further supports the previously published morphologic evidence for a microtubule-dependent system of collagen secretion in periodontal ligament fibroblasts

93

Proliferation and osteogenic differentiation of human periodontal ligament cells on akermanite and ?-TCP bioceramics  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this study was to investigate the effects of akermanite as compared to ?-TCP on attachment, proliferation, and osteogenic differentiation of human periodontal ligament cells (hPDLCs. Scanning electron microscopy (SEM and actin filament labeling were used to reveal attachment and growth of hPDLCs seeded on ?-TCP and akermanite ceramic. Cell proliferation was tested by lactic acid production and MTT analysis, while osteogenic differentiation was assayed by alkaline phosphatase (ALP expression and real-time polymerase chain reaction (PCR analysis on markers of osteopontin (OPN, dentin matrix acidic phosphoprotein-1 (DMP-1, and osteocalcin (OCN, and further detected by enzyme-linked immunosorbent analysis (ELISA analysis for OCN expression. Besides, the ions released from akermanite and their effect on hPDLCs was also measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES, MTT analysis, ALP expression and real-time PCR analysis. hPDLCs attached well on both ceramics, but showed better spreading on akermanite. hPDLCs proliferated more rapidly on akermanite than ?-TCP. Importantly, osteogenic differentiation of hPDLCs was enhanced on akermanite compared to ?-TCP. Besides, Ca, Mg and Si ions were released from akermanite, while only Ca ions were released from ?-TCP. Moreover, more pronounced proliferation and higher osteogenic gene expression for hPDLCs cultured with akermanite extract were detected as compared to cells cultured on akermanite. Therefore, akermanite ceramic showed an enhanced effect on proliferation and osteogenic differentiation of hPDLCs, which might be attributed to the release of ions containing Ca, Mg and Si from the material. It is suggested that akermanite ceramics may serve as a potential material for periodontal bone regeneration.

L Xia

2011-07-01

94

Immunolocalization of FGF-2 and VEGF in rat periodontal ligament during experimental tooth movement  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o objetivo desse estudo foi identificar a expressão do fator de crescimento de fibroblastos 2 (FGF-2) e do fator de crescimento vascular endotelial (VEGF) nos lados de tensão e pressão do ligamento periodontal de ratos, durante movimento ortodôntico experimental, em diferentes períodos d [...] e tempo. MÉTODOS: uma força ortodôntica de 0,5N foi aplicada no primeiro molar superior direito de 18 ratos Wistar machos, por períodos de 3 (grupo I), 7 (grupo II) e 14 dias (grupo III). O primeiro molar do lado oposto foi utilizado como controle. Os animais foram sacrificados nos períodos de tempo mencionados, sendo a arcada superior removida e fixada. Após a desmineralização, os espécimes foram processados histologicamente e embebidos em parafina. A expressão do FGF-2 e do VEGF foram estudadas por meio de análise imuno-histoquímica. RESULTADOS: o ligamento periodontal dos dentes submetidos à movimentação ortodôntica mostraram maior expressão tanto de FGF-2 quanto de VEGF, em todos os grupos experimentais, quando comparados com os dentes do lado controle (p Abstract in english OBJECTIVE: This article aimed at identifying the expression of fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF) in the tension and pressure areas of rat periodontal ligament, in different periods of experimental orthodontic tooth movement. METHODS: An orthodonti [...] c force of 0.5 N was applied to the upper right first molar of 18 male Wistar rats for periods of 3 (group I), 7 (group II) and 14 days (group III). The counter-side first molar was used as a control. The animals were euthanized at the aforementioned time periods, and their maxillary bone was removed and fixed. After demineralization, the specimens were histologically processed and embedded in paraffin. FGF-2 and VEGF expressions were studied through immunohistochemistry and morphological analysis. RESULTS: The experimental side showed a higher expression of both FGF-2 and VEGF in all groups, when compared with the control side (P

Milene Freitas Lima, Salomão; Sílvia Regina de Almeida, Reis; Vera Lúcia Costa, Vale; Cintia de Vasconcellos, Machado; Roberto, Meyer; Ivana Lucia Oliveira, Nascimento.

2014-06-01

95

Zanthoxylum schinifolium enhances the osteogenic potential of periodontal ligament stem cells.  

Science.gov (United States)

The present study demonstrates the osteogenic effect of Zanthoxylum schinifolium on periodontal ligament stem cells (PDLSCs). The dried herb of Z. schinifolium was first extracted with 70% ethanol and subsequently fractionated into five parts: n-hexane, methylene chloride (MC), ethyl acetate (EA), n-butanol (BuOH), and water fractions. The proliferation of PDLSCs was first assessed and increased by hexane, EA, or BuOH fraction of Z. schinifolium. We evaluated the osteogenic differentiation of PDLSCs by alkaline phosphatase (ALP) activity, messenger RNA (mRNA) expression of runt-related transcription factor 2 (RUNX2), osterix (OSX), FOSB, and FRA-1 as osteogenic transcription factors, and protein levels of osteopontin (OPN) and RUNX2 in response to each hexane, MC, EA, BuOH, or water fraction of Z. schinifolium. The significant ALP activity appeared in PDLSCs treated with hexane, EA, or BuOH fraction. The mRNA expression of osteogenic transcription factors was also increased by hexane, EA, or BuOH fraction with doses of 5, 10, 25, and 50 ?g/ml compared to control group. We further assessed immunofluorescence staining with OPN and RUNX2 confirmed that the treatment of hexane, EA, or BuOH fraction enhances PDLSC osteogenic differentiation. In conclusion, these data suggest that fractions from Z. schinifolium differentially regulate PDLSC function. Among them, proliferation and osteogenic potential of PDLSCs were enhanced by hexane, EA, or BuOH fraction. PMID:25303944

Kim, So Yeon; An, Seong Yeong; Lee, Jeong Seok; Heo, Jung Sun

2014-10-11

96

Biodegradable polymer scaffolds loaded with low-dose BMP-2 stimulate periodontal ligament cell differentiation.  

Science.gov (United States)

Poly(l-lactide)-co-(epsilon-caprolactone) [poly(LLA-co-CL)] and poly(l-lactide)-co-(1,5-dioxepan-2-one) [poly(LLA-co-DXO)] are being considered candidate scaffolds for bone tissue engineering. We evaluated the bioactive potential of poly(LLA-co-CL) and poly(LLA-co-DXO) scaffolds loaded with low-dose bone morphogenetic protein-2 (BMP-2). Periodontal ligament (PDL) cells were cultured onto the various scaffolds loaded with 1 µg BMP-2 or without BMP-2 (control). Cell viability, attachment, and proliferation were determined using a methylthiazol tetrazolium (MTT) colorimetric assay at day 1, 3, and 7. Scanning electron microscopy was used to analyze cell morphology at day 7. Cell differentiation was evaluated assaying alkaline phosphatase (ALP) activity at day 7, 14, and 21. Real-time PCR was used to evaluate the mRNA expression of periostin, ALP, type I collagen, bone sialoprotein and BMP-2. A commercially available enzyme-linked immunosorbent assay was used to assess BMP-2 production. Surface analysis disclosed excellent cell attachment, spread, and penetration into the porous scaffolds. The MTT assay indicated that scaffolds loaded with low concentration of BMP-2 did not influence the viability of cells. Cells grown on the modified scaffolds expressed higher levels of osteogenic markers than the nonmodified scaffolds (p?BMP-2 exhibited a significant effect stimulating PDL differentiation suggesting a continued evaluation in relevant in vivo models. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2014. PMID:25231842

Skodje, Anders; Idris, Shaza Bushra M; Sun, Yang; Bartaula, Sushma; Mustafa, Kamal; Finne-Wistrand, Anna; Wikesjö, Ulf M E; Leknes, Knut N

2014-09-18

97

Mechanical Strength and Viscoelastic Response of the Periodontal Ligament in Relation to Structure  

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Full Text Available The mechanical strength of the periodontal ligament (PDL was first measured as force required to extract a tooth from its socket using human specimens. Thereafter, tooth-PDL-bone preparations have extensively been used for measurement of the mechanical response of the PDL. In vitro treatments of such specimens with specific enzymes allowed one to investigate into the roles of the structural components in the mechanical support of the PDL. The viscoelastic responses of the PDL may be examined by analysis of the stress-relaxation. Video polarised microscopy suggested that the collagen molecules and fibrils in the stretched fibre bundles progressively align along the deformation direction during the relaxation. The stress-relaxation process of the PDL can be well expressed by a function with three exponential decay terms. Analysis after in vitro digestion of the collagen fibres by collagenase revealed that the collagen fibre components may play an important role in the long-term relaxation component of the stress-relaxation process of the PDL. The dynamic measurements of the viscoelastic properties of the PDL have recently suggested that the PDL can absorb more energy in compression than in shear and tension. These viscoelastic mechanisms of the PDL tissue could reduce the risk of injury to the PDL.

Koichiro Komatsu

2010-01-01

98

Osteogenesis induction of periodontal ligament cells onto bone morphogenic protein-2 immobilized PCL fibers.  

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The purpose of this study was to develop bone morphogenic protein-2 (BMP-2) immobilized PCL fibers to induce osteogenic differentiation of periodontal ligament cells (PDLCs). The PCL fiber surface was modified with heparin-dopamine (Hep-DOPA) (Hep-PCL) and further immobilized with BMP-2 (BMP-2/Hep-PCL). PCL fibers and surface-modified PCL fibers (Hep-PCL and BMP-2/Hep-PCL) were characterized by X-ray photoelectron spectroscopy (XPS) and contact angle. Osteogenic differentiation of PDLCs was demonstrated by alkaline phosphatase (ALP) activity, calcium deposition, and gene expression. The results of XPS and contact angle revealed that Hep-DOPA and BMP-2 were successfully immobilized onto the PCL surface and that the BMP-2/Hep-PCL fibers have more hydrophilic surface properties than PCL fibers alone. ALP activity, calcium deposition, and gene expression on BMP-2/Hep-PCL fibers showed significantly induced osteogenic differentiation relative to PCL fibers. Therefore, we suggest that BMP-2/Hep-PCL fibers have the potential to effectively induce osteogenic differentiation of PDLCs. PMID:24274561

Kim, Sung Eun; Yun, Young-Pil; Han, Yun-Kyung; Lee, Deok-Won; Ohe, Joo-Young; Lee, Baek-Soo; Song, Hae-Ryong; Park, Kyeongsoon; Choi, Byung-Joon

2014-01-01

99

Effects of non-thermal atmospheric plasma on human periodontal ligament mesenchymal stem cells  

International Nuclear Information System (INIS)

Here we investigate the influences of non-thermal atmospheric plasma on human mesenchymal stem cells isolated from periodontal ligament (hPDL-MSCs). A specially redesigned plasma needle was used as the source of low-temperature plasma and its effects on different hPDL-MSC functions were investigated. Cell cultures were obtained from extracted normal impacted third molars and characterized for their phenotype and multi-potential differentiation. The hPDL-MSCs possessed all the typical MSC properties, including clonogenic ability, high proliferation rate, specific phenotype and multilineage differentiation. The data regarding the interaction of plasma with hPDL-MSCs demonstrated that plasma treatment inhibited the migration of hPDL-MSCs and induced some detachment, while not affecting their viability. Additionally, plasma significantly attenuated hPDL-MSCs' proliferation, but promoted their osteogenic differentiation. The results of this study indicated that a non-thermal plasma offers specific activity with non-destructive properties that can be advantageous for future dental applications. (paper)

100

Effects of non-thermal atmospheric plasma on human periodontal ligament mesenchymal stem cells  

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Here we investigate the influences of non-thermal atmospheric plasma on human mesenchymal stem cells isolated from periodontal ligament (hPDL-MSCs). A specially redesigned plasma needle was used as the source of low-temperature plasma and its effects on different hPDL-MSC functions were investigated. Cell cultures were obtained from extracted normal impacted third molars and characterized for their phenotype and multi-potential differentiation. The hPDL-MSCs possessed all the typical MSC properties, including clonogenic ability, high proliferation rate, specific phenotype and multilineage differentiation. The data regarding the interaction of plasma with hPDL-MSCs demonstrated that plasma treatment inhibited the migration of hPDL-MSCs and induced some detachment, while not affecting their viability. Additionally, plasma significantly attenuated hPDL-MSCs' proliferation, but promoted their osteogenic differentiation. The results of this study indicated that a non-thermal plasma offers specific activity with non-destructive properties that can be advantageous for future dental applications.

Mileti?, M.; Mojsilovi?, S.; Oki? ?or?evi?, I.; Maleti?, D.; Pua?, N.; Lazovi?, S.; Malovi?, G.; Milenkovi?, P.; Petrovi?, Z. Lj; Bugarski, D.

2013-08-01

101

Comparative gene-expression analysis of the dental follicle and periodontal ligament in humans.  

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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. PMID:24376796

Lee, Hyo-Seol; Lee, Jongeun; Kim, Seong-Oh; Song, Je-Seon; Lee, Jae-Ho; Lee, Syng-Ill; Jung, Han-Sung; Choi, Byung-Jai

2013-01-01

102

Determination of periodontal ligament cell viability in long shelf-life milk.  

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The purpose of this study was to determine the ability of long shelf-life milk to serve as a temporary storage medium for the maintenance of periodontal ligament (PDL) cell viability on avulsed teeth. PDL cells were plated onto 24-well culture plates and allowed to attach for 24 h. Minimal Essential Medium was replaced with regular pasteurized milk (refrigerated milk), long shelf-life milk (Parmalat), or Save-A-Tooth. Tap water served as the negative control, and Minimal Essential Medium served as the positive control. The tissue culture plates were incubated at 37 degrees C for 1, 2, 4, or 8 h. Cell viability was determined using a cell proliferation assay (CellTiter 96 AQ Assay) and absorbance read at 490 nm. ANOVA indicated that all media performed significantly better than tap water at all time periods. At 8 h, PDL cell viability in regular pasteurized milk and long shelf-life milk were significantly greater than in Save-A-Tooth (p < or = 0.001). There was no significant difference between regular pasteurized milk and long shelf-life milk at any time period. These results suggest that long shelf-life milk, which has the advantage of not requiring refrigeration, is as effective a storage medium for avulsed teeth as regular pasteurized milk and more effective than Save-A-Tooth. PMID:11471636

Marino, T G; West, L A; Liewehr, F R; Mailhot, J M; Buxton, T B; Runner, R R; McPherson, J C

2000-12-01

103

SSEA-4 is a marker of human deciduous periodontal ligament stem cells.  

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Although human deciduous teeth are an ideal source of adult stem cells, no method for identifying deciduous periodontal ligament (D-PDL) stem cells has so far been developed. In the present study, we investigated whether stage-specific embryonic antigen (SSEA)-4 is a marker that could be used to isolate D-PDL stem cells. The isolated D-PDL cells met the minimum criteria for mesenchymal stem cells (MSCs): They showed plastic adherence, specific-surface antigen expression, and multipotent differentiation potential. SSEA-4+ D-PDL cells were detected in vitro and in vivo. A flow cytometric analysis demonstrated that 22.7% of the D-PDL cells were positive for SSEA-4. SSEA-4+ clonal D-PDL cells displayed multilineage differentiation potential: They were able to differentiate into adipocytes, osteoblasts, and chondrocytes in vitro. A clonal assay demonstrated that 61.5% of the SSEA-4+ D-PDL cells had adipogenic, osteogenic, and chondrogenic potential. Our present study demonstrated that SSEA-4+ D-PDL cells are a subset of multipotent stem cells. Hence, SSEA-4 is a specific marker that can be used to identify D-PDL stem cells. PMID:22895512

Fukushima, H; Kawanabe, N; Murata, S; Ishihara, Y; Yanagita, T; Balam, T A; Yamashiro, T

2012-10-01

104

Effect of storage in media with different ion strengths and osmolalities on human periodontal ligament cells  

International Nuclear Information System (INIS)

The viability of the periodontal ligament (PDL) cells is critical for a successful healing of replanted exarticulated teeth. It is mainly dependent on the duration of the extra-alveolar time and the storage medium. Saliva has usually been recommended as the most suitable storage medium, but recent experimental studies indicate that milk is preferable. In the present study the effect on cultured PDL cells of saliva and milk has been compared with some reference media such as tap water or saline by means of a 3H-uridine leakage test. Storage in milk or saline was found to cause much less 3H-uridine leakage than storage in saliva or tap water. Cells stored in milk for 60-180 min showed about the same leakage as cells stored in saline or Hanks' balanced salt solution. Osmolality measurements showed that saliva was hypotonic, while the osmolality of milk ranged within physiological limits. When the osmolality of saliva was increased by addition of NaCl the leakage of the stored cells decreased to the level of cells stored in 0.9% NaCl or milk. (author)

105

Enhanced compatibility of chemically modified titanium surface with periodontal ligament cells  

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A simple chemical modification method was developed to immobilize cell-adhesive molecules on a titanium surface to improve its compatibility with human periodontal ligament cells (HPDLCs).The polished titanium disk was immersed in 1% (v/v) p-vinylbenzoic acid solution for 2 h to introduce carboxyl groups onto the surface. After rinsing with distilled deionized water, the titanium disk was dipped into 1.47% 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide solution containing 0.1 mg/ml Gly-Arg-Gly-Asp-Ser (GRGDS), human plasma fibronectin (pFN), or type I collagen from calf skin (Col) to covalently immobilize the cell-adhesive molecules on the titanium surface via formation of peptide bonds. X-ray photoelectron spectroscopy analyses revealed that cell-adhesive molecules were successfully immobilized on the titanium surfaces. The Col-immobilized titanium surface revealed higher values regarding nano rough characteristics than the as-polished titanium surface under scanning probe microscopy. The number of HPDLCs attached to both the pFN- and Col-immobilized titanium surfaces was twice that attached to the as-polished titanium surfaces. The cells were larger with the cellular processes that stretched to a greater extent on the pFN- and Col-immobilized titanium surfaces than on the as-polished titanium surface (p implants.

Kado, T.; Hidaka, T.; Aita, H.; Endo, K.; Furuichi, Y.

2012-12-01

106

The biomechanical behaviour of the hyalinized periodontal ligament in dogs during experimental orthodontic tooth movement.  

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During orthodontic tooth movement, the mechanical behaviour of the extracellular matrix of the periodontal ligament (PDL) determines the cellular processes involved in turnover of the PDL and alveolar bone. This mechanical behaviour is the basis for finite element (FE) models and FE analyses. Five young adult male beagle dogs were used to test the null hypothesis that the mechanical behaviour of the PDL is identical in normal and hyalinized PDL. Therefore, tooth transposition was measured after standardized force application by super-elastic nickel titanium (NiTi) coil springs, exerting a constant force of 100 cN for 5 hours in both conditions. A rapid transposition during the first few seconds was found. However, it was significantly less for hyalinized than for non-hyalinized PDL. Subsequently, a short-lived creep movement was found for hyalinized PDL, while creep persisted at the non-hyalinized sides (analysis of variance and Tukey's multiple comparisons post hoc tests). The results showed substantial biomechanical differences between hyalinized and non-hyalinized PDL at different time points (Mann-Whitney). This indicates that FE models in the study of long-term orthodontic tooth movement, which are based solely on the characteristics of normal PDL should be reconsidered. PMID:21478299

Jónsdóttir, S H; Giesen, E B W; Maltha, J C

2012-10-01

107

Mechanical response of periodontal ligament: effects of specimen geometry, preconditioning cycles and time lapse.  

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This study was conducted as part of research line addressing the mechanical response of periodontal ligament (PDL) to tensile-compressive sinusoidal loading. The aim of the present project was to determine the effect of three potential sources of variability: (1) specimen geometry, (2) tissue preconditioning and (3) tissue structural degradation over time. For the three conditions, selected mechanical parameters were evaluated and compared. (1) Standard flat specimens (obtained by sequentially slicing portions of bone, PDL and dentin using a precision band saw) and new cylindrical specimens (extracted with a diamond-coated trephine drill) were obtained from bovine mandibular first molars and subjected to a sinusoidal load profile. (2) Specimens were loaded with up to 2000 cycles. (3) Specimens were immersed in saline and tested after 0, 30 and 60 min. From the data generated, the following was concluded: (1) specimen geometry and preparation technique do not influence the mechanical response of the PDL; (2) the mechanical response stabilizes after approximately 1000 cycles; and (3) no major structural degradation occurs when PDL is immersed in saline for a time lapse up to 60 min. PMID:19665135

Bergomi, Marzio; Anselm Wiskott, H W; Botsis, John; Shibata, Tatsuya; Belser, Urs C

2009-10-16

108

Attachment and proliferation of human periodontal ligament fibroblasts on bioactive glass modified ceramics.  

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In this study, six groups of modified ceramic specimens were constructed and were studied comparatively with dental porcelain (P:control) for their ability to support human periodontal ligament fibroblasts attachment and proliferation. The dental porcelain was initially coated with bioactive glass (PCB) or with a mixture of porcelain and bioactive glass (PCBP) and then calcium-phosphate rich (Ca-P) or hydroxy-carbonate apatite (HCAp) layers were bio-mimetically developed on both surfaces (PCB and PCBP) after immersion in simulated body fluid. The development and characterization of Ca-P and HCAp layers on PCBCa-P, PCBHCAp, PCBPCa-P, PCBPHCAp specimens' surfaces were evaluated by Scanning Electron Microscopy (SEM) and further confirmed by Fourier Transform Infrared Spectroscopy (FTIR). The modified ceramics differed from their controls concerning their surface morphology as evaluated by SEM, and their surface chemical composition (Al, P, Si, Ca, Na and K) as evaluated by Energy Dispersive Spectroscopy (EDS). Almost all modified specimens supported cell attachment, spreading and proliferation at higher extent than the control porcelain specimens. The additional layers of Ca-P or HCAp on PCBP and PCB specimens were found to positively affect cell attachment and proliferation. The highest cell population, of all specimens tested, was observed on PCBPCa-P and PCBPHCAp. The Ca-P particles present on all Ca-P and HCAp coated specimens seemed to be involved in cell adhesion. PMID:17207079

Kontonasaki, E; Sivropoulou, A; Papadopoulou, L; Garefis, P; Paraskevopoulos, K; Koidis, P

2007-01-01

109

Modificações no periodonto de ratos diabéticos após a movimentação ortodôntica / Periodontal ligament changes after induced dental movement in diabetic rats  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVOS: o objetivo deste trabalho foi avaliar as modificações do ligamento periodontal de incisivos de ratos diabéticos submetidos a forças ortodônticas. MÉTODOS: vinte ratos machos Wistar (Rattus norvegicus) com 105 dias de idade foram empregados. Os ratos foram divididos em quatro grupos: C - a [...] nimais normoglicêmicos não submetidos à movimentação dentária; CAO - animais normoglicêmicos submetidos à movimentação dentária; D - animais diabéticos não submetidos à movimentação dentária; DAO - animais diabéticos submetidos à movimentação dentária. Os animais permaneceram com o dispositivo de movimentação dentária por 5 dias. Foram avaliados o número de vasos sangüíneos e a espessura do ligamento periodontal nos terços cervical, médio e apical dos cortes histológicos. RESULTADOS E CONCLUSÕES: no lado de tensão, a movimentação dentária nos animais do grupo CAO resultou em um ligamento periodontal mais espesso (17,64% no terço apical, 39,28% no terço médio e 51,35% na região cervical), quando comparado ao grupo C (p 0,05). Ainda no lado de tensão, foram observadas lacunas de reabsorção nos animais dos grupos CAO, D e DAO. O lado de pressão não foi examinado nesta fase do estudo. Abstract in english AIM: The aim of this study was to evaluate the periodontal ligament changes after induced dental movement of the upper incisor in diabetic rats. METHODS: Twenty Wistar rats (Rattus norvegicus) with 105 days of age were used. The rats were divided in four groups: C - normoglicemic animals not submitt [...] ed to dental movement; CAO - normoglicemic animals submitted to dental movement; D - diabetic animals not submitted the dental movement; DAO - diabetic animals submitted to dental movement. The animals had remained with dental movement devices during 5 days. The number of sanguine vessels and the thickness of the periodontal ligament were evaluated at cervical, medium and apical histological cut regions. RESULTS AND CONCLUSION: At tension side, the dental movement in the animals of group CAO resulted in a thicker periodontal ligament (17.64% apical, 39.28% medium, 51.35% cervical) when compared to C group (p

Luis Alberto Sabino Vila, Real; Adilson Luiz, Ramos; Jacqueline Nelisis, Zanoni.

2009-02-01

110

Expresión de la osteocalcina en el ligamento periodontal al inducir fuerzas ortodóncicas / Osteocalcin expression in periodontal ligament when inducing orthodontic forces  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish La osteocalcina es una proteína no colágena presente en hueso alveolar, cemento radicular y subpoblaciones del ligamento periodontal. Esta proteína juega un papel importante en la biomineralización y en la matriz extracelular regulando la maduración de los cristales de hidroxiapatita y en el recluta [...] miento de los osteoclastos participando en la remodelación ósea. La remodelación y la nueva formación de tejido periodontal es parte esencial durante los movimientos ortodóncicos, los cuales al aplicar fuerzas causan tensión en las células provocando una adaptación que se traduce en respuestas celulares y moleculares que pueden afectar la matriz extracelular. Por ello, el propósito de esta investigación fue determinar la expresión de la osteocalcina asociada a la remodelación periodontal cuando se aplican fuerzas ortodóncicas. En primeros premolares superiores e inferiores se colocó aparatología fija prescripción Roth 0.022 con un arco NiTi 0.016, la cual se aplicó a todos los dientes de ambas arcadas con excepción de los premolares superiores e inferiores izquierdos. Los premolares sin aparatología (t = 0) y en presencia de aparatología para inducir movimientos ortodóncicos durante 1, 3, 5, 7 y 9 días; fueron extraídos para analizar la expresión de la osteocalcina en la matriz extracelular del ligamento periodontal. Para determinar la expresión temporal y espacial de los mensajeros de la osteocalcina en el ligamento periodontal se llevó a cabo la técnica RT-PCR. La expresión de la osteocalcina en el grupo experimental estuvo presente en todos los días de prueba, sugiriendo que los movimientos ortodónticos generan cambios que son susceptibles en las concentraciones del mensajero de la proteína osteocalcina. Abstract in english Osteocalcin is a non-collagenous protein located in alveolar bone, root cementum and subpopulations of periodontal ligament cells. This protein plays an important role in the biomineralization process and in the extra-cellular matrix, regulating maturation of hydroxyapatite and osteoclast recruitmen [...] t which participate in bone remodeling. Periodontal tissue new formation and remodeling is a vital part of the process during orthodontic movements. These movements, when force is exerted, cause tension in the cells, provoking adaptation which results in molecular and cellular responses which, in turn, can affect the extracellular matrix. Due to the aforementioned facts, the aim of the present research was to determine osteocalcin expression associated to periodontal remodeling when orthodontic forces are applied. Roth 0.022 " fixed brackets with a NiTi 0.016" archwire were applied to first upper and lower bicuspids. This was applied to all teeth of both arches except to left lower and upper bicuspids. Bicuspids without brackets (t = 0) as well as with brackets to elicit orthodontic movements during 1, 3, 5, 7 and 9 days were extracted to assess osteocalcin expression in the extra-cellular matrix of the periodontal ligament. The RT-PCR technique was followed to determine temporal and spatial expression of osteocalcin messengers. Osteocalcin expression in the experimental group was present in all test days, suggesting thus the fact that orthodontic movements elicit changes that are susceptible in osteocalcin protein messenger concentrations.

Maritere, Villarreal Brito; Marco Antonio, Álvarez Pérez; Francisco Javier, Marichi Rodríguez.

2013-09-01

111

Combination of platelet-rich plasma within periodontal ligament stem cell sheets enhances cell differentiation and matrix production.  

Science.gov (United States)

The longstanding goal of periodontal therapy is to regenerate periodontal tissues. Although platelet-rich plasma (PRP) has been gaining increasing popularity for use in the orofacial region, whether PRP is useful for periodontal regeneration is still unknown. The purpose of this study was to determine whether a mixture of periodontal ligament stem cell (PDLSC) sheets and PRP promoted bone regeneration, one of the most important measurement indices of periodontal tissue regenerative capability in vitro and in vivo. In this study, we evaluated the effects of different doses of PRP on the differentiation of human PDLSCs. Then cell sheet formation, extracellular matrix deposition and osteogenic gene expression in response to different doses of PRP treatment during sheet grafting was investigated. Furthermore, we implanted PDLSC sheets treated with 1% PRP subcutaneously into immunocompromised mice to evaluate their bone-regenerative capability. The results revealed that 1% PRP significantly enhanced the osteogenic differentiation of PDLSCs. Based on the production of extracellular matrix proteins, the results of scanning electron microscopy and the expression of the osteogenic genes ALP, Runx2, Col-1 and OCN, the provision of 1% PRP for PDLSC sheets was the most effective PRP administration mode for cell sheet formation. The results of in vivo transplantation showed that 1% PRP-mediated PDLSC sheets exhibited better periodontal tissue regenerative capability than those obtained without PRP intervention. These data suggest that a suitable concentration of PRP stimulation may enhance extracellular matrix production and positively affect cell behaviour in PDLSC sheets. Copyright © 2014 John Wiley & Sons, Ltd. PMID:25186188

Xu, Qiu; Li, Bei; Yuan, Lin; Dong, Zhiwei; Zhang, Hao; Wang, Han; Sun, Jin; Ge, Song; Jin, Yan

2014-09-01

112

Comparative gene expression analysis of the human periodontal ligament in deciduous and permanent teeth.  

Science.gov (United States)

There are histological and functional differences between human deciduous and permanent periodontal ligament (PDL) tissues. The aim of this study was to determine the differences between these two types of tissue at the molecular level by comparing their gene expression patterns. PDL samples were obtained from permanent premolars (n = 38) and anterior deciduous teeth (n = 31) extracted from 40 healthy persons. Comparative cDNA microarray analysis revealed several differences in gene expression between the deciduous and permanent PDL tissues. These findings were verified by qRT-PCR (quantitative reverse-transcription-polymerase chain reaction) analysis, and the areas where genes are expressed were revealed by immunohistochemical staining. The expressions of 21 genes were up-regulated in deciduous relative to PDL tissues, and those of 30 genes were up-regulated in permanent relative to deciduous PDL tissues. The genes that were up-regulated in deciduous PDL tissues were those involved in the formation of the extracellular matrix (LAMC2, LAMB3, and COMP), tissue development (IGF2BP, MAB21L2, and PAX3), and inflammatory or immune reactions leading to tissue degradation (IL1A, CCL21, and CCL18). The up-regulated genes in permanent PDL tissues were related to tissue degradation (IL6 and ADAMTS18), myocontraction (PDE3B, CASQ2, and MYH10), and neurological responses (FOS, NCAM2, SYT1, SLC22A3, DOCK3, LRRTM1, LRRTM3, PRSS12, and ARPP21). The analysis of differential gene expressions between deciduous and permanent PDL tissues aids our understanding of histological and functional differences between them at the molecular level. PMID:23593441

Song, Je Seon; Hwang, Dong Hwan; Kim, Seong-Oh; Jeon, Mijeong; Choi, Byung-Jai; Jung, Han-Sung; Moon, Seok Jun; Park, Wonse; Choi, Hyung-Jun

2013-01-01

113

Bone morphogenetic protein 7 induces cementogenic differentiation of human periodontal ligament-derived mesenchymal stem cells.  

Science.gov (United States)

Bone morphogenetic protein 7 (BMP-7) is a multifunctional differentiation factor that belongs to the transforming growth factor superfamily. BMP-7 induces gene expression of protein tyrosine phosphatase-like, member A/cementum attachment protein (PTPLA/CAP) and cementum protein 1 (CEMP1), both of which are markers of cementoblasts and cementocytes. In the previous study, we reported that BMP-7 treatment enhanced PTPLA/CAP and CEMP1 expression in both normal and immortal human periodontal ligament (PDL) cells. To elucidate the molecular mechanisms of the gene expression of these molecules, in this study, we identified a functional transcription activator binding region in the promoter region of PTPLA/CAP and CEMP1 that is responsive to BMP signals. Here, we report that some short motifs termed GC-rich Smad-binding elements (GC-SBEs) that are located in the human PTPLA/CAP promoter and CEMP1 promoter are BMP-7 responsive as analyzed with luciferase promoter assays. On the other hand, we found that transcription of Sp7/Osterix and PTPLA/CAP was up-regulated after 1 week of BMP-7 treatment on purified normal human PDL cells as a result of gene expression microarray analysis. Furthermore, transcription of Sp7/Osterix, runt-related transcription factor 2 (RUNX2), and alkaline phosphatase (ALP) was up-regulated after 2 weeks of BMP-7 treatment, whereas gene expression of osteo/odontogenic markers such as integrin-binding sialoprotein (IBSP), collagen, type I, alpha 1 (COL1A1), dentin matrix acidic phosphoprotein 1 (DMP1), and dentin sialophosphoprotein (DSPP) was not up-regulated in purified normal or immortal human PDL cells as a result of qRT-PCR. The results suggest that BMP-7 mediates cementogenesis via GC-SBEs in human PDL cells and that its molecular mechanism is different from that for osteo/odontogenesis. PMID:25464857

Torii, D; Tsutsui, T W; Watanabe, N; Konishi, K

2014-12-01

114

Analysis of contribution of collagen fibre component in viscoelastic behaviour of periodontal ligament using enzyme probe.  

Science.gov (United States)

The aims of this study are to observe microscopic changes in the periodontal ligament (PDL) collagen fibres after collagenase treatment, to analyse stress-relaxation behaviour of PDL specimens treated with collagenase, and to elucidate the contribution of the collagen component to the viscoelastic behaviour of the PDL. Transverse sections of rat mandibular first molars (n=24) were treated in vitro with 0, 8, 16, or 24 units of bacterial collagenase for 4h at 37 degrees C. Histological specimens were then prepared, and image analyses were done for polarised light microscopic appearances of collagen fibres. Further, stress-relaxation tests were performed for PDL specimens treated with 8 units of collagenase (n=7) and control specimens (n=7). Image analysis showed that higher concentrations of collagenase reduced greater area occupied by the PDL collagen fibres and birefringent retardation of the fibres. The amount of stress-relaxation during 600 s was 1.37 times greater in the collagenase-treated specimens than in the controls. The observed values of the stress-relaxation process were well described by a function with three exponential decay terms. The relaxation parameters of the first and second terms did not show significant differences, but those of the third term did so between the collagenase-treated and control specimens. The ratio and relaxation time of the third term for the collagenase-treated specimens were significantly less than those for the controls. These findings suggest that in the long-term relaxation component of the stress-relaxation process of the PDL the viscoelastic properties of the collagen fibres may play an important role. PMID:17266965

Komatsu, Koichiro; Shibata, Tatsuya; Shimada, Akemi

2007-01-01

115

Effect of icariin on cell proliferation and the expression of bone resorption/formation-related markers in human periodontal ligament cells.  

Science.gov (United States)

Periodontitis is a common destructive inflammatory disease that leads to changes in the tooth-supporting tissues. Human periodontal ligament cells are essential in periodontal tissue regeneration. The traditional Chinese medicine icariin promoted bone formation, stimulated the osteogenic differentiation of preosteoblastic cells and inhibited osteoclast differentiation and bone resorption. Thus, in the present study, the effect of icariin on cell proliferation and the expression of osteoprotegerin (OPG), receptor activator of nuclear factor-?B ligand (RANKL), core binding factor ?1 (Cbfa1) and osteocalcin (OC) was investigated in human periodontal ligament cells, by an MTT assay, qPCR and western blot analysis. The results demonstrated that icariin promoted cell proliferation in a dose- and time-dependent manner, upregulated OPG, Cbfa1 and OC expression, and downregulated RANKL production and the RANKL/OPG expression ratio. This suggested the potential value of icariin in treating alveolar bone resorption and promoting periodontal tissue regeneration, due to its ability to stimulate the proliferation and osteogenic differentiation of human periodontal ligament cells and inhibit osteoclast differentiation. PMID:24065204

Pei, Zhenhua; Zhang, Fengqiu; Niu, Zhongying; Shi, Shenggen

2013-11-01

116

Rendimento de células mesenquimais do ligamento periodontal humano submetidas a diferentes protocolos de criopreservação / Yield of human periodontal ligament mesenchymal cells under different protocols of cryopreservation  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese INTRODUÇÃO: A técnica de criopreservação tem como característica cessar reversivelmente todas as funções biológicas dos tecidos vivos em baixas temperaturas e tem sido aplicada a diversas células humanas, visando à sua utilização posterior. OBJETIVO: Avaliar a proliferação de células mesenquimais do [...] ligamento periodontal humano após a criopreservação por dois diferentes protocolos. MÉTODO: As células do ligamento periodontal foram obtidas a partir de dois dentes (terceiros molares) hígidos, com indicação de remoção cirúrgica. Após o processamento, as células foram cultivadas em placas de Petri e mantidas a 37 °C em 5% de CO2, até atingirem 70-90% de confluência, com troca de meio a cada três dias. Na primeira passagem, as células foram divididas em dois grupos e criopreservadas: Grupo -80 °C - criopreservação em ultrafreezer por 45 dias; Grupo -196 °C - criopreservação em nitrogênio líquido por 45 dias. Decorrido esse tempo, as células dos dois grupos foram descongeladas e plaqueadas para o experimento. A curva de crescimento dos grupos estudados foi traçada a partir de contagem em Câmara de Neubauer e pelo método de ensaio do MTT, nos intervalos de 24, 48 e 72 horas. Os resultados foram analisados por meio do teste de Mann?Whitney, com nível de significância de 5%. RESULTADO: Verificou-se um crescimento ascendente nos dois protocolos utilizados, porém uma maior taxa proliferativa foi verificada no grupo criopreservado em nitrogênio líquido (p Abstract in english INTRODUCTION: Cryopreservation aims to stop reversibly the biological functions of living tissues at low temperatures, and is an important resource for the storage of human cells for later use. AIM: To assess the proliferation of mesenchymal cells from human periodontal ligament cryopreserved by two [...] different protocols. METHOD: Periodontal ligament cells were obtained from third molars with an indication for surgical removal. After processing, cells were grown and maintained at 37 °C in 5% CO2 until they reached 70-90% confluency, with medium changing every three days. In the first passage cells were divided into two groups, according to the protocol used: Group -80 °C - cryopreserved in ultrafreezer for 45 days, Group -196 °C - cryopreserved in liquid nitrogen for 45 days. After this time, cells from both groups were thawed and plated for the experiment. The growth curve of the groups was drawn from counting cells in a Neubauer chamber and by the MTT assay method, in the intervals of 24, 48 and 72 hours. The data were analyzed using the Mann-Whitney test with a significance level of 5%. RESULT: There was an upward cell growth in both protocols used, but a higher proliferative rate was observed in group cryopreserved in liquid nitrogen (p

Diego Moura, Soares; Fernanda, Ginani; Carlos Augusto Galvão, Barboza.

2012-12-01

117

Acute changes in intra-alveolar tooth position and local clearance of 125I from the periodontal ligament  

International Nuclear Information System (INIS)

Changes in intra-alveolar tooth position and local 125I clearance from the periodontal ligament (PDL) were monitored simultaneously in cats. Axial tooth movements, reflecting periodontal ligament volume changes, were measured with an ultrasonic transit time technique. Local blood flow changes in the PDL were studied indirectly by measuring the local clearance of 125I. Stimulation of the cervical sympathetic trunk caused an intrusive movement of the tooth with a concomitant reduction of the 125I-clearance. Infusion of noradrenaline induced a similar respone. Stimulation of the inferior alveolar nerve during systemic treatment with phentolamine caused an extrusive movement of the tooth with a concomitant increase in the clearance of the tracer from the PDL. Intra-arterial infusion of the vasodilator substance P mimicked that response. Fization of the tooth to the jaw bone, thus preventing an intrusive movement, did not change the reductions in clearance seen on sympathetic stimulation, indicating that this blood flow reduction was not dependent on tooth movement. A qualitative relation between PDL blood flow (as measured by local 125I clearance) and PDL volume (as measured by tooth position) in shown. The two variables measured are suggested to reflect two aspects of blood flow in the PDL

118

Mechanical design, analysis, and laboratory testing of a dental implant with axial flexibility similar to natural tooth with periodontal ligament.  

Science.gov (United States)

At the interface between the jawbone and the roots of natural teeth, a thin, elastic, shock-absorbing tissue, called the periodontal ligament, forms a cushion which provides certain flexibility under mechanical loading. The dental restorations supported by implants, however, involve comparatively rigid connections to the jawbone. This causes overloading of the implant while bearing functional loading together with neighboring natural teeth, which leads to high stresses within the implant system and in the jawbone. A dental implant, with resilient components in the upper structure (abutment) in order to mimic the mechanical behavior of the periodontal ligament in the axial direction, was designed, analyzed in silico, and produced for mechanical testing. The aims of the design were avoiding high levels of stress, loosening of the abutment connection screw, and soft tissue irritations. The finite element analysis of the designed implant revealed that the elastic abutment yielded a similar axial mobility with the natural tooth while keeping stress in the implant at safe levels. The in vitro mechanical testing of the prototype resulted in similar axial mobility predicted by the analysis and as that of a typical natural tooth. The abutment screw did not loosen under repeated loading and there was no static or fatigue failure. PMID:25378380

Pekta?, Ömer; Tönük, Ergin

2014-11-01

119

"THE STUDY OF DOSE-RESPONSE MITOGENIC EFFECT OF L-DOPA ON THE HUMAN PERIODONTAL LIGAMENT FIBROBLAST CELLS"  

Directory of Open Access Journals (Sweden)

Full Text Available Avulsion is one of the most serious emergencies in dental office. In the event of any problem, the tooth should be stored in a medium that supports the periodontal ligament cell viability. In other clinical situations, preserving media, growth factors and mitogenic products may be useful in repairing the traumatized tissues. It has been previously reported that levodopa (L-dopa accelerates healing by increasing the growth hormone level. In this study, the local effect of L-dopa, as a mitogen, on human periodontal ligament fibroblast (HPLF cells was evaluated. Samples from impacted or semiimpacted wisdom or canine teeth, which were devoid of inflammation, were taken. The cells obtained from this tissue were cultured in an appropriate medium. The passage numbers between 3-6 were taken for further experiments. The viability of HPLF cells, which were treated by L-dopa, was evaluated by trypan blue dye exclusion and neutral red assay. Results indicated that low concentration of L-dopa produces significant increase of these cells compared to control group. These results confirmed previous studies about direct action of L- dopa on the viability of HPLF cells. On the basis of this study and previous reports, presence of L-dopa in preserving media may be useful in increasing the self-life transferring HPLF cells.

M. Zarabian

2004-10-01

120

Beneficial Effects of Adiponectin on Periodontal Ligament Cells under Normal and Regenerative Conditions  

OpenAIRE

Type 2 diabetes and obesity are increasing worldwide and linked to periodontitis, a chronic disease which is characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium. The mechanisms underlying the association of diabetes mellitus and obesity with periodontal destruction and compromised periodontal healing are not well understood, but decreased plasma levels of adiponectin, as found in diabetic and obese individuals, might be a critical mechanistic l...

Nokhbehsaim, Marjan; Keser, Sema; Nogueira, Andressa Vilas Boas; Cirelli, Joni Augusto; Jepsen, Søren; Ja?ger, Andreas; Eick, Sigrun; Deschner, James

2014-01-01

121

Establishment of immortalized periodontal ligament progenitor cell line and its behavioural analysis on smooth and rough titanium surface  

Directory of Open Access Journals (Sweden)

Full Text Available Periodontal ligament (PDL can be obtained from patients undergoing orthodontic treatment. PDL contains progenitor cells that can be expanded and differentiated towards several mesenchymal lineages in vitro. Furthermore, PDL-derived cells have been shown to generate bone- and PDL-like structures in vivo. Thus, PDL cells, combined with suitable biomaterials, represent a promising tool for periodontitis-related research and PDL engineering.Here, a new PDL cell line using lentiviral gene transfer of human telomerase reverse transcriptase (hTERT was created. HTERT-expressing PDL cells showed similar morphology and population doubling time but an extended lifespan compared to the primary cells. In addition, PDL-hTERT cells expressed several characteristic genes and upon osteogenic stimulation produced a calcified matrix in vitro. When cultivated on two topographically different titanium scaffolds (MA and SLA, PDL-hTERT cells exhibited augmented spreading, survival and differentiation on smooth (MA compared to rough (SLA surfaces. These findings differ from previously reported osteoblast behaviour, but they are in agreement with the behaviour of chondrocytes and gingival fibroblasts, suggesting a very cell type-specific response to different surface textures.In summary, we report the testing of titanium biomaterials using a new PDL-hTERT cell line and propose this cell line as a useful model system for periodontitis research and development of novel strategies for PDL engineering.

D Docheva

2010-05-01

122

Establishment of immortalized periodontal ligament progenitor cell line and its behavioural analysis on smooth and rough titanium surface.  

Science.gov (United States)

Periodontal ligament (PDL) can be obtained from patients undergoing orthodontic treatment. PDL contains progenitor cells that can be expanded and differentiated towards several mesenchymal lineages in vitro. Furthermore, PDL-derived cells have been shown to generate bone- and PDL-like structures in vivo. Thus, PDL cells, combined with suitable biomaterials, represent a promising tool for periodontitis-related research and PDL engineering. Here, a new PDL cell line using lentiviral gene transfer of human telomerase reverse transcriptase (hTERT) was created. HTERT-expressing PDL cells showed similar morphology and population doubling time but an extended lifespan compared to the primary cells. In addition, PDL-hTERT cells expressed several characteristic genes and upon osteogenic stimulation produced a calcified matrix in vitro. When cultivated on two topographically different titanium scaffolds (MA and SLA), PDL-hTERT cells exhibited augmented spreading, survival and differentiation on smooth (MA) compared to rough (SLA) surfaces. These findings differ from previously reported osteoblast behaviour, but they are in agreement with the behaviour of chondrocytes and gingival fibroblasts, suggesting a very cell type-specific response to different surface textures. In summary, we report the testing of titanium biomaterials using a new PDL-hTERT cell line and propose this cell line as a useful model system for periodontitis research and development of novel strategies for PDL engineering. PMID:20473831

Docheva, D; Padula, D; Popov, C; Weishaupt, P; Prägert, M; Miosge, N; Hickel, R; Böcker, W; Clausen-Schaumann, H; Schieker, M

2010-01-01

123

Both 25-hydroxyvitamin-D3 and 1,25-dihydroxyvitamin-D3 reduces inflammatory response in human periodontal ligament cells.  

Science.gov (United States)

Periodontitis is an inflammatory disease leading to the destruction of periodontal tissue. Vitamin D3 is an important hormone involved in the preservation of serum calcium and phosphate levels, regulation of bone metabolism and inflammatory response. Recent studies suggest that vitamin D3 metabolism might play a role in the progression of periodontitis. The aim of the present study was to examine the effects of 25(OH)D3, which is stable form of vitamin D3 in blood, and biologically active form 1,25(OH)2D3 on the production of interleukin-6 (IL-6), interleukin-8 (IL-8), and monocyte chemotactic protein-1 (MCP-1) by cells of periodontal ligament. Commercially available human periodontal ligament fibroblasts (hPdLF) and primary human periodontal ligament cells (hPdLC) were used. Cells were stimulated with either Porphyromonas gingivalis lipopolysaccharide (LPS) or heat-killed P. ginigvalis in the presence or in the absence of 25(OH)D3 or 1,25(OH)2D3 at concentrations of 10-100 nM. Stimulation of cells with either P. gingivalis LPS or heat-killed P. gingivalis resulted in a significant increase of the expression levels of IL-6, IL-8, and MCP-1 in gene as well as in protein levels, measured by qPCR and ELISA, respectively. The production of these pro-inflammatory mediators in hPdLF was significantly inhibited by both 25(OH)D3 and 1,25(OH)2D3 in a dose-dependent manner. In primary hPdLCs, both 25(OH)D3 and 1,25(OH)2D3 inhibited the production of IL-8 and MCP-1 but have no significant effect on the IL-6 production. The effect of both 25(OH)D3 and 1,25(OH)2D3 was abolished by specific knockdown of vitamin D3 receptor by siRNA. Our data suggest that vitamin D3 might play an important role in the modulation of periodontal inflammation via regulation of cytokine production by cells of periodontal ligament. Further studies are required for better understanding of the extents of this anti-inflammatory effect and its involvement in the progression of periodontal disease. PMID:24587317

Andrukhov, Oleh; Andrukhova, Olena; Hulan, Ulamnemekh; Tang, Yan; Bantleon, Hans-Peter; Rausch-Fan, Xiaohui

2014-01-01

124

Effects of hydroxyapatite nanostructure on channel surface of porcine acellular dermal matrix scaffold on cell viability and osteogenic differentiation of human periodontal ligament stem cells.  

Science.gov (United States)

A new nanostructured hydroxyapatite-coated porcine acellular dermal matrix (HAp-PADM) was fabricated by a biomimetic mineralization method. Human periodontal ligament stem cells were seeded on HAp-PADM and the effects of this scaffold on cell shape, cytoskeleton organization, cell viability, and osteogenic differentiation were examined. Periodontal ligament stem cells cultured on HAp-PADM exhibited different cell shape when compared with those on pure PADM. Moreover, HAp-PADM promoted cell viability and alkaline phosphatase activity significantly. Based on quantitative real-time polymerase chain reaction, the expression of bone-related markers runt-related transcription factor 2 (Runx2), osteopontin (OPN), and osteocalcin (OCN) upregulated in the HAp-PADM scaffold. The enhancement of osteogenic differentiation of periodontal ligament stem cells on the HAp-PADM scaffold was proposed based on the research results. The results of this study highlight the micro-nano, two-level, three-dimensional HAp-PADM composite as a promising scaffold for periodontal tissue engineering. PMID:23690686

Ge, Shaohua; Zhao, Ning; Wang, Lu; Liu, Hong; Yang, Pishan

2013-01-01

125

Effects of hydroxyapatite nanostructure on channel surface of porcine acellular dermal matrix scaffold on cell viability and osteogenic differentiation of human periodontal ligament stem cells  

Directory of Open Access Journals (Sweden)

Full Text Available Shaohua Ge,1 Ning Zhao,1 Lu Wang,1 Hong Liu,2 Pishan Yang11Shandong Provincial Key Laboratory of Oral Biomedicine, Department of Periodontology, Shandong University; 2State Key Laboratory of Crystal Materials, Center of Bio and Micro/Nano Functional Materials, Shandong University, Jinan, People's Republic of ChinaAbstract: A new nanostructured hydroxyapatite-coated porcine acellular dermal matrix (HAp-PADM was fabricated by a biomimetic mineralization method. Human periodontal ligament stem cells were seeded on HAp-PADM and the effects of this scaffold on cell shape, cytoskeleton organization, cell viability, and osteogenic differentiation were examined. Periodontal ligament stem cells cultured on HAp-PADM exhibited different cell shape when compared with those on pure PADM. Moreover, HAp-PADM promoted cell viability and alkaline phosphatase activity significantly. Based on quantitative real-time polymerase chain reaction, the expression of bone-related markers runt-related transcription factor 2 (Runx2, osteopontin (OPN, and osteocalcin (OCN upregulated in the HAp-PADM scaffold. The enhancement of osteogenic differentiation of periodontal ligament stem cells on the HAp-PADM scaffold was proposed based on the research results. The results of this study highlight the micro-nano, two-level, three-dimensional HAp-PADM composite as a promising scaffold for periodontal tissue engineering.Keywords: hydroxyapatite, scaffold, nanostructure, proliferation, differentiation, tissue engineering

Ge S

2013-05-01

126

Effect of the simulated periodontal ligament on cast post-and-core removal using an ultrasonic device  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english ABSTRACT OBJECTIVE: The aim of this study was to evaluate the effect of simulated periodontal ligament (SPDL) on custom cast dowel and core removal by ultrasonic vibration. MATERIAL AND METHODS: Thirty-two human maxillary canines were included in resin cylinders with or without SPDL made from polyet [...] her impression material. In order to allow tensile testing, the roots included in resin cylinders with SPDL were fixed to cylinders with two stainless steel wires. Post-holes were prepared by standardizing the length at 8 mm and root canal impressions were made with self-cured resin acrylic. Cast dowel and core sets were fabricated and luted with Panavia F resin cement. Half of the samples were submitted to ultrasonic vibration before the tensile test. Data were analyzed statistically by two-way ANOVA and Tukey's post-hoc tests (p

Manoel, Brito-Junior; Neilor Mateus Antunes, Braga; Danilo Costa, Rodrigues; Carla Cristina, Camilo; André Luis, Faria-e-Silva.

2010-10-01

127

Biomechanical validation of an artificial tooth–periodontal ligament–bone complex for in vitro orthodontic load measurement  

Science.gov (United States)

Objectives To develop an artificial tooth–periodontal ligament (PDL)–bone complex (ATPBC) that simulates clinical crown displacement. Material and Methods An ATPBC was created. It had a socket hosting a tooth with a thin layer of silicon mixture in between for simulating the PDL. The complex was attached to a device that allows applying a controlled force to the crown and measuring the resulting crown displacement. Crown displacements were compared to previously published data for validation. Results The ATPBC that had a PDL made of two types of silicones, 50% gasket sealant No. 2 and 50% RTV 587 silicone, with a thickness of 0.3 mm, simulated the PDL well. The mechanical behaviors (1) force-displacement relationship, (2) stress relaxation, (3) creep, and (4) hysteresis were validated by the published results. Conclusion The ATPBC simulated the crown displacement behavior reported from biological studies well. PMID:22970752

Xia, Zeyang; Chen, Jie

2014-01-01

128

Microscopic evaluation of the effect of different storage media on the periodontal ligament of surgically extracted human teeth.  

Science.gov (United States)

The objective of this study was to microscopically evaluate the human periodontal ligament adhered to extracted teeth, after extra-alveolar period of 1 h using, as storage media, pasteurized milk (group I), chicken egg white (group II) and artificial saliva (group III). Forty intact premolars were selected, with indication of tooth extraction for orthodontic reasons. After the extraction of 30 teeth, they were maintained dried on a gauze at room temperature for 10 min, and then immersed in the selected storage media. After the established time, the teeth were washed with saline solution and placed in 10.0% buffered formalin. Ten teeth were extracted and immediately immersed in 10.0% neutral formalin (group IV). Thereafter, they were submitted to histological processing. After fixation and decalcification, the specimens were cut at the cervical, medium and apical thirds, inserted in paraffin and serially sectioned, with 6-mum thickness. They were stained by hematoxylin-eosin and analyzed under light microscopy. According to the results of quantitative analysis, there was no statistically significant difference in the number of cells per mm(2) between groups I, II and III. The qualitative analysis showed similar results in relation to the organization of collagen fibers and the number of cells in groups I and II, but group III displayed a higher disorganization of the collagen fibers and also a higher reduction in the number of cells. Based on these results, it was concluded that the quality of periodontal ligament was affected by the storage media, when compared with the control group. There was a statistically significant difference in the number of cells per mm(2) between the control group and groups I, II and III. There was no significant statistical difference in the number of cells per mm(2) between groups I, II and III. PMID:19021655

de Sousa, Hugo Alexandre; de Alencar, Ana Helena G; Bruno, Kely Firmino; Batista, Aline Carvalho; de Carvalho, Antônio César Perri

2008-12-01

129

Predicting the holistic force-displacement relation of the periodontal ligament: in-vitro experiments and finite element analysis  

Science.gov (United States)

Background The biomechanical property of the periodontal ligament (PDL) is important in orthodontics and prosthodontics. The objective of this study was to evaluate the feasibility of measuring the biomechanical behavior of the periodontal ligament using micro-computed tomography (micro-CT). Methods A custom-made apparatus measured the force and displacement of a porcine PDL specimen within the micro-CT environment. Synchronized computed tomography (CT) images were used to obtain the deformation and displacement of the entire specimen and to reconstruct the three-dimensional mesh model. To match the experimental results, finite element analysis was then applied to simulate the biomechanical response of the PDL. The mechanical model of the PDL was assumed as the hyperelastic material in this study. Results The volume variations of the tooth and the alveolar bone were less than 1%, which implies that tooth displacement was caused mostly by displacement of the PDL. Only translational displacement was observed with each load step because the transformation matrix acquired from the CT image registration was identical. The force-displacement curve revealed the nonlinear behavior of the PDL. There was a high correlation between the experimental displacement results and the simulation displacement results. The numerical results (based on the assumption that the PDL is the hyperelastic material) showed good agreement with the experimental results. Conclusions Nondestructive measurements by micro-CT obtained the biomechanical behavior of the PDL. Using the hyperelastic characteristic as the constitutive model can properly predict the force-displacement relation of the PDL after loading. This study provided a feasible approach for measuring the biomechanical behavior of the PDL for further dental application. PMID:25077405

2014-01-01

130

Isolation and characterization of multipotent mesenchymal stromal cells from the gingiva and the periodontal ligament of the horse  

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Full Text Available Abstract Background The equine periodontium provides tooth support and lifelong tooth eruption on a remarkable scale. These functions require continuous tissue remodeling. It is assumed that multipotent mesenchymal stromal cells (MSC reside in the periodontal ligament (PDL and play a crucial role in regulating physiological periodontal tissue regeneration. The aim of this study was to isolate and characterize equine periodontal MSC. Tissue samples were obtained from four healthy horses. Primary cell populations were har-vested and cultured from the gingiva, from three horizontal levels of the PDL (apical, midtooth and subgingival and for comparison purposes from the subcutis (masseteric region. Colony-forming cells were grown on uncoated culture dishes and typical in vitro characteristics of non-human MSC, i.e. self-renewal capacity, population doubling time, expression of stemness markers and trilineage differentiation were analyzed. Results Colony-forming cell populations from all locations showed expression of the stemness markers CD90 and CD105. In vitro self-renewal capacity was demonstrated by colony-forming unit fibroblast (CFU-F assays. CFU-efficiency was highest in cell populations from the apical and from the mid-tooth PDL. Population doubling time was highest in subcutaneous cells. All investigated cell populations possessed trilineage differentiation potential into osteogenic, adipogenic and chondrogenic lineages. Conclusions Due to the demonstrated in vitro characteristics cells were referred to as equine subcutaneous MSC (eSc-MSC, equine gingival MSC (eG-MSC and equine periodontal MSC (eP-MSC. According to different PDL levels, eP-MSC were further specified as eP-MSC from the apical PDL (eP-MSCap, eP-MSC from the mid-tooth PDL (eP-MSCm and eP-MSC from the subgingival PDL (eP-MSCsg. Considering current concepts of cell-based regenerative therapies in horses, eP-MSC might be promising candidates for future clinical applications in equine orthopedic and periodontal diseases.

Pfarrer Christiane

2011-08-01

131

Human Periodontal Ligament Derived Progenitor Cells: Effect of STRO-1 Cell Sorting and Wnt3a Treatment on Cell Behavior  

Science.gov (United States)

Objectives. STRO-1 positive periodontal ligament cells (PDLCs) and unsorted PDLCs have demonstrated potential for periodontal regeneration, but the comparison between unsorted cells and the expanded STRO-1 sorted cells has never been reported. Additionally, Wnt3a is involved in cell proliferation thus may benefit in vitro PDLC expansion. The aim was to evaluate the effect of STRO-1 cell sorting and Wnt3a treatment on cell behavior of human PDLCs (hPDLCs). Materials and Methods. STRO-1 positive hPDLCs were sorted and the sorted cells were expanded and compared with their unsorted parental cells. Thereafter, hPDLCs were treated with or without Wnt3a and the cell proliferation, self-renewal, and osteogenic differentiation were evaluated. Results. No differences were measured between the expanded STRO-1-sorted cells and unsorted parental cells in terms of proliferation, CFU, and mineralization capacity. Wnt3a enhanced the proliferation and self-renewal ability of hPDLCs significantly as displayed by higher DNA content values, a shorter cell population doubling time, and higher expression of the self-renewal gene Oct4. Moreover, Wnt3a promoted the expansion of hPDLCs for 5 passages without affecting cell proliferation, CFU, and osteogenic capacity. Conclusions. Expanded STRO-1-sorted hPDLCs showed no superiority compared to their unsorted parental cells. On the other hand, Wnt3a promotes the efficient hPDLC expansion and retains the self-renewal and osteogenic differentiation capacity. PMID:24864228

Yan, Xiang-Zhen; Both, Sanne K.; Yang, Pi-Shan; Jansen, John A.; van den Beucken, Jeroen J. J. P.; Yang, Fang

2014-01-01

132

Scleraxis and osterix antagonistically regulate tensile force-responsive remodeling of the periodontal ligament and alveolar bone.  

Science.gov (United States)

The periodontal ligament (PDL) is a mechanosensitive noncalcified fibrous tissue connecting the cementum of the tooth and the alveolar bone. Here, we report that scleraxis (Scx) and osterix (Osx) antagonistically regulate tensile force-responsive PDL fibrogenesis and osteogenesis. In the developing PDL, Scx was induced during tooth eruption and co-expressed with Osx. Scx was highly expressed in elongated fibroblastic cells aligned along collagen fibers, whereas Osx was highly expressed in the perialveolar/apical osteogenic cells. In an experimental model of tooth movement, Scx and Osx expression was significantly upregulated in parallel with the activation of bone morphogenetic protein (BMP) signaling on the tension side, in which bone formation compensates for the widened PDL space away from the bone under tensile force by tooth movement. Scx was strongly expressed in Scx(+)/Osx(+) and Scx(+)/Osx(-) fibroblastic cells of the PDL that does not calcify; however, Scx(-)/Osx(+) osteogenic cells were dominant in the perialveolar osteogenic region. Upon BMP6-driven osteoinduction, osteocalcin, a marker for bone formation was downregulated and upregulated by Scx overexpression and knockdown of endogenous Scx in PDL cells, respectively. In addition, mineralization by osteoinduction was significantly inhibited by Scx overexpression in PDL cells without affecting Osx upregulation, suggesting that Scx counteracts the osteogenic activity regulated by Osx in the PDL. Thus, Scx(+)/Osx(-), Scx(+)/Osx(+) and Scx(-)/Osx(+) cell populations participate in the regulation of tensile force-induced remodeling of periodontal tissues in a position-specific manner. PMID:25670797

Takimoto, Aki; Kawatsu, Masayoshi; Yoshimoto, Yuki; Kawamoto, Tadafumi; Seiryu, Masahiro; Takano-Yamamoto, Teruko; Hiraki, Yuji; Shukunami, Chisa

2015-02-15

133

A Three-Dimensional Cell Culture Model to Study the Mechano-Biological Behavior in Periodontal Ligament Regeneration  

Science.gov (United States)

Periodontitis is a disease affecting the supporting structures of the teeth, which can eventually result in tooth loss. A three-dimensional (3D) tissue culture model was developed that may serve to grow a 3D construct that not only transplants into defective periodontal sites, but also allows to examine the effect of mechanical load in vitro. In the current in vitro study, green fluorescent protein labeled periodontal ligament (PDL) cells form rat incisors were embedded in a 3D matrix and exposed to mechanical loading alone, to a chemical stimulus (Emdogain; enamel matrix derivative [EMD]) alone, or a combination of both. Loading consisted of unilateral stretching (8%, 1?Hz) and was applied for 1, 3, or 5 days. Results showed that PDL cells were distributed and randomly oriented within the artificial PDL space in static culture. On mechanical loading, the cells showed higher cell numbers. Moreover, cells realigned perpendicular to the stretching force depending on time and position, with great analogy to natural PDL tissue. EMD application gave a significant effect on growth and upregulated bone sialoprotein (BSP) and collagen type-I (Col-I), whereas Runx-2 was downregulated. This implies that PDL cells under loading might tend to act similar to bone-like cells (BSP and Col-I) but at the same time, react tendon like (Runx-2). The combination of chemical and mechanical stimulation seems possible, but does not show synergistic effects. In this study, a new model was successfully introduced in the field of PDL-related regenerative research. Besides validating the 3D model to mimic an authentic PDL space, it also provided a useful and well-controlled approach to study cell response to mechanical loading and other stimuli. PMID:21913838

Oortgiesen, Daniel A.W.; Yu, Na; Bronckers, Antonius L.J.J.; Yang, Fang; Walboomers, X. Frank

2012-01-01

134

Effects of Continuous and Interrupted Forces on Gene Transcription in Periodontal Ligament Cells in Vitro  

OpenAIRE

The biological mechanisms of tooth movement are based on the response of periodontal tissues to mechanical forces. The final result of these responses is remodeling of the extracellular matrix. Tissue reactions may vary depending upon the type, magnitude and duration of the applied forces. The purpose of the present study was to analyze the effects of centrifugal force on the transcription of collagen type-I (Col-I), matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of metalloproteinas...

Seyed Nasser Ostad; Hamid Reza Rahimi; Mohammad Hossein Ghahremani; Tahereh Hosseinzadeh Nik; Ninette Hacopian

2011-01-01

135

Influence of root embedment material and periodontal ligament simulation on fracture resistance tests / Influência do material de inclusão e da simulação do ligamento periodontal nos ensaios de resistência à fratura  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo deste estudo foi avaliar a influência do material de inclusão e da simulação de ligamento periodontal na resistência à fratura de dentes bovinos. Oitenta incisivos bovinos foram divididos em 8 grupos (n = 10) e, então, incluídos em cilindros com dois materiais, resina acrílica ou resina d [...] e poliestireno, usando-se quatro tipos de simulação do ligamento periodontal: 1 - ausência do ligamento; 2 - material de moldagem à base de poliéter; 3 - material de moldagem à base de polissulfeto; e 4 - material elastomérico à base de poliuretano. As amostras foram armazenadas em 100% de umidade a 37°C por 24 horas e então submetidas a carregamento tangencial na superfície palatina com velocidade de 0,5 mm/minuto até a fratura. Os padrões de fratura foram analisados de acordo com: 1 - fraturas coronais; 2 - fratura da junção esmalte-cemento; 3 - fratura parcial da raiz; 4 - fratura radicular total. A análise estatística empregou análise de variância fatorial e teste de Tukey (p Abstract in english The aim of this study was to evaluate the influence of the embedment material and periodontal ligament simulation on fracture resistance of bovine teeth. Eighty bovine incisor teeth were randomized into 8 groups (n = 10), embedded in acrylic or polystyrene resin using 4 types of periodontal ligament [...] simulation: 1 - absence of the ligament; 2 - polyether impression material; 3 - polysulfide impression material; 4 - polyurethane elastomeric material. The specimens were stored at 37°C and 100% humidity for 24 hours. Specimens were submitted to tangential load on the palatal surface at 0.5 mm/minute crosshead speed until fracture. The fracture modes were analyzed as follows: 1 - coronal fracture; 2 - cemento-enamel junction fracture; 3 - partial root fracture; 4 - total root fracture. Statistical analyses by two-way ANOVA and Tukey's test were applied (p

Carlos José, Soares; Eliane Cristina Gava, Pizi; Rodrigo Borges, Fonseca; Luis Roberto Marcondes, Martins.

2005-03-01

136

Estrogen-related receptor ? is involved in the osteogenic differentiation of mesenchymal stem cells isolated from human periodontal ligaments.  

Science.gov (United States)

Recently, it has been reported that the orphan nuclear receptor estrogen-related receptor ? (ERR?) is involved in the osteogenic differentiation of mesenchymal stem cells (MSCs). Moreover, ERR? has been identified as a novel therapeutic target for treating osteoporosis and other bone diseases. Human periodontal ligament tissue-derived mesenchymal stem cells (hPDLSCs) have recently been used in stem cell-mediated therapies because of their multipotency, particularly toward osteogenic differentiation. However, it is still unclear whether ERR? can regulate the osteogenic differentiation of hPDLSCs. In the present study, we investigated the role of ERR? in the osteogenic differentiation of hPDLSCs in vitro. We isolated hPDLSCs and confirmed their capacity for multipotent differentiation. Furthermore, we examined ERR? expression in hPDLSCs by RT-PCR and immunocytochemistry. We found that the expression of ERR? mRNA was significantly increased during the late stage of osteogenic differentiation of hPDLSCs. Moreover, transfection of recombinant lentiviral-mediated miRNA targeting ERR? significantly suppressed ALP activity, mineralization capacity, and the mRNA expression of osteogenesis-related genes (ALP, OCN, RUNX2 and OPN) in hPDLSCs. Our results indicate that ERR? may promote the osteogenic differentiation of hPDLSCs in vitro. PMID:23525223

Cai, Chuan; Yuan, Gong-Jie; Huang, Ye; Yang, Nan; Chen, Xin; Wen, Li; Wang, Xi; Zhang, Liang; Ding, Yin

2013-05-01

137

Effect of the simulated periodontal ligament on cast post-and-core removal using an ultrasonic device  

Directory of Open Access Journals (Sweden)

Full Text Available ABSTRACT OBJECTIVE: The aim of this study was to evaluate the effect of simulated periodontal ligament (SPDL on custom cast dowel and core removal by ultrasonic vibration. MATERIAL AND METHODS: Thirty-two human maxillary canines were included in resin cylinders with or without SPDL made from polyether impression material. In order to allow tensile testing, the roots included in resin cylinders with SPDL were fixed to cylinders with two stainless steel wires. Post-holes were prepared by standardizing the length at 8 mm and root canal impressions were made with self-cured resin acrylic. Cast dowel and core sets were fabricated and luted with Panavia F resin cement. Half of the samples were submitted to ultrasonic vibration before the tensile test. Data were analyzed statistically by two-way ANOVA and Tukey's post-hoc tests (p<0.05. RESULTS: The ultrasonic vibration reduced the tensile strength of the samples directly included in resin cylinders. There was no difference between the values, whether or not ultrasonic vibration was used, when the PDL was simulated. However, the presence of SPDL affected the tensile strength values even when no ultrasonic vibration was applied. CONCLUSION: Simulation of PDL has an effect on both ultrasonic vibration and tensile testing.

Manoel Brito-Junior

2010-10-01

138

The vasculature of the periodontal ligament: a scanning electron microscopic study using corrosion casts in the rat.  

Science.gov (United States)

The purpose of this study was to examine the 3-dimensional architecture of the microvascular system of the rat periodontal ligament (PDL). Vascular corrosion casts were prepared and examined by scanning electron microscopy. Cervically, arterioles and venules communicated with the profuse capillary network of the gingiva. The mid-root segment of the PDL contained arterioles and venules that mainly coursed occluso-apically near the alveolar wall, as well as capillary loops located closer to the root surface. Arterioles entered the PDL through vascular canals from the bone marrow, then coursed coronally and branched into an interconnected network of capillaries. The capillaries formed hairpin loops pointing coronally. At the tip, the capillary loops were enlarged in diameter and had an irregular luminar surface. The capillaries then coursed apically, anastomosing freely, until entering a venule. Large venules mainly followed a coronal-apical path, giving the PDL vasculature a palisade-like appearance. These vessels either left the PDL through vascular canals in the alveolar wall or connected in an apical, venous cap with venules exiting through the apical foramen. The results show that the microvasculature forms a highly organized system presumably related to the specialized functions of the periodontium. Cervically, a dense capillary system may be required for antimicrobial defense and rapid tissue turnover. The vasculature in the middle segment supports the suspensory structures, while the venous cap in the apical region may be designed to cushion masticatory forces.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7853133

Selliseth, N J; Selvig, K A

1994-11-01

139

Osteogenesis differentiation of human periodontal ligament cells by CO2 laser-treatment stimulating macrophages via BMP2 signalling pathway  

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Immune reactions play an important role in determining the biostimulation of bone formation, either in new bone formation or inflammatory fibrous tissue encapsulation. Macrophage cell, the important effector cells in the immune reaction, which are indispensable for osteogenesis and their heterogeneity and plasticity, render macrophages a primer target for immune system modulation. However, there are very few studies about the effects of macrophage cells on laser treatment-regulated osteogenesis. In this study, we used CO2 laser as a model biostimulation to investigate the role of macrophage cells on the CO2 laser stimulated osteogenesis. Bone morphogenetic protein 2 (BMP2) was also significantly up regulated by the CO2 laser stimulation, indicating that macrophage may participate in the CO2 laser stimulated osteogenesis. Interestingly, when laser treatment macrophage-conditioned medium were applied to human periodontal ligament cells (hPDLs), the osteogenesis differentiation of hPDLs was significantly enhanced, indicating the important role of macrophages in CO2 laser-induced osteogenesis. These findings provided valuable insights into the mechanism of CO2 laser-stimulated osteogenic differentiation, and a strategy to optimize the evaluation system for the in vitro osteogenesis capacity of laser treatment.

Hsieh, Wen-Hui; Chen, Yi-Jyun; Hung, Chi-Jr; Huang, Tsui-Hsien; Kao, Chia-Tze; Shie, Ming-You

2014-11-01

140

[Stress analysis of the periodontal ligament of the human tooth using a three-dimensional finite element method].  

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Three-dimensional finite element analysis is used to determine the physiological stress values in periodontal ligament (PDL). In comparison with the elastic modulus E of PDL, the E of dentin and bone are much larger. For the estimation of the stresses in PDL, the tooth and the supporting bone can be considered to be rigid. The finite element model of PDL of the mandibular right first molar consists of 210 elements (20-node isoparametric element) and 1612 nodes. Eleven load cases were selected in the study, which included the longitudinal occlusive load, buccal lingual lateral load, mesial-distal lateral load and other load cases to simulate the actual occlusive loads. The results obtained from this study lead to the following conclusions: 1. The loads which go through the physiological center of the tooth, the stresses induced by the loads which are compressive and relatively small. There are no tensile stresses. 2. Among eleven load cases studied in this work, the following three load cases are most harmful. a. The maximum tensile stress was found under mesial-distal lateral load; b. The maximum compressive stress was found under longitudinal occlusive load on the buccal groove or lingual groove; c. The highest stress concentration was found under buccal-lingual lateral load. The clinical significance of the results has also been discussed in the paper. PMID:2517822

Zhou, S M

1989-11-01

141

Differential expression of osteo-modulatory molecules in periodontal ligament stem cells in response to modified titanium surfaces.  

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This study assessed differential gene expression of signaling molecules involved in osteogenic differentiation of periodontal ligament stem cells (PDLSCs) subjected to different titanium (Ti) surface types. PDLSCs were cultured on tissue culture polystyrene (TCPS), and four types of Ti discs (PT, SLA, hydrophilic PT (pmodPT), and hydrophilic SLA (modSLA)) with no osteoinductive factor and then osteogenic activity, including alkaline phosphatase (ALP) activity, mRNA expression of runt-related gene 2, osterix, FOSB, FRA1, and protein levels of osteopontin and collagen type IA, were examined. The highest osteogenic activity appeared in PDLSCs cultured on SLA, compared with the TCPS and other Ti surfaces. The role of surface properties in affecting signaling molecules to modulate PDLSC behavior was determined by examining the regulation of Wnt pathways. mRNA expression of the canonical Wnt signaling molecules, Wnt3a and ?-catenin, was higher on SLA and modSLA than on smooth surfaces, but gene expression of the calcium-dependent Wnt signaling molecules Wnt5a, calmodulin, and NFATc1 was increased significantly on PT and pmodPT. Moreover, integrin ?2/?1, sonic hedgehog, and Notch signaling molecules were affected differently by each surface modification. In conclusion, surface roughness and hydrophilicity can affect differential Wnt pathways and signaling molecules, targeting the osteogenic differentiation of PDLSCs. PMID:25057487

Kim, So Yeon; Yoo, Ji-Yeon; Ohe, Joo-Young; Lee, Jung-Woo; Moon, Ji-Hoi; Kwon, Yong-Dae; Heo, Jung Sun

2014-01-01

142

An electron microscopic radioautographic study of collagen secretion in periodontal ligament fibroblasts of the mouse: II. Colchicine-treated fibroblasts  

International Nuclear Information System (INIS)

Colchicine administered intravenously depolymerized microtubules and disrupted the normal organization of the Golgi apparatus in periodontal ligament fibroblasts. Radioautography with 3H-proline indicated that collagen secretion was completely inhibited during a period of approximately 4 hours following the onset of the colchicine effect. During this period of secretory inhibition, labeled collagen precursors were present within a variety of dense bodies, primarily located in a juxtanuclear location replacing the normal Golgi complex. The time course of 3H-proline labeling from 2 to 8 hours suggested that small, newly formed dense bodies fused to form larger dense bodies and pleomorphic structures (zebra bodies), within which collagen precursors appeared to undergo partial polymerization. Autophagosomes, many labeled with 3H-proline, also increased in number after colchicine administration. A gradual decline in 3H-proline label occurred from 4 to 24 hours, presumably due to exocytosis of dense bodies or by the digestion of labeled collagen precursors within autophagosomes. These results support the concept that an intact microtubular network is essential for the organized transport of collagen precursors, from the rough endoplasmic reticulum to the Golgi apparatus, and the eventual transport and exocytosis of collagen secretory granules

143

Comparación del efecto citotóxico de tres agentes quelantes sobre fibroblasto del ligamento periodontal humano. Estudio in vitro / Comparison of the cytotoxic effect of three chelating agents on human periodontal ligament fibroblast. In vitro study  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish Objetivo: Comparar in vitro el efecto citotóxico de tres agentes quelantes sobre fibroblastos del ligamento periodontal humano. Materiales y métodos: Se utilizaron cultivos de fibroblastos de ligamento periodontal humano, los cuales fueron colocados en contacto con los agentes quelantes a evaluar (R [...] C-Prep, Glyde, EDTA al 17%) a intervalos de 15, 30 y 60 minutos. Se midió la absorbancia para cada uno de los grupos, para determinar el grado de actividad enzimática, que es indicador de muerte celular. Previo a la cuantificación de la absorbancia se corroboró microscópicamente la formación de los cristales de formazán, los cuales se forman alrededor de los fibroblastos, y su presencia es indicador de integridad de la membrana y de la actividad metabólica. Por microscopia se verificó la formación de cristales de formazan, después de agregar azul de tripán. Resultados: El Glyde mostró mayor grado de citotoxicidad, con una diferencia estadísticamente significativa, al compararlo con EDTA 17% y el RC-PREP. El EDTA presentó mayor citotoxicidad que el RC-PREP a los 15minutos, evento que cambió a los 30 y 60 minutos. Conclusiones: Los agentes quelantes RC-Prep, Glyde y EDTA tienen un efecto citotóxico a nivel de los fibroblastos del ligamento periodontal, siendo el EDTA el de menor efecto citotóxico a los 30 y 60 minutos comparado con RC-Prep y Glyde Abstract in english Objectives: To compare in vitro, the cytotoxic effect of three chelating agents on human periodontal ligament fibroblasts, RC-Prep, Glyde and EDTA. Methods: Fibroblast cultures of human periodontal ligament were used, which are placed in contact with chelating agents to evaluate (RC-Prep, Glyde, 17% [...] EDTA) at time intervals of 15,30 and 60 minutes. Absorbance was measured for each group to determine the degree of enzyme activity, which is an indicator of cell death. Prior to the measurement of absorbance was confirmed microscopically, the formation of formazan crystals, which are formed around fibroblasts, and its presence is an indicator of membrane integrity and metabolic activity. Microscopy verified the formation of formazan crystals, after adding trypan blue. Results: Glyde showed greater cytotoxicity with a statistically significant difference when compared with 17% EDTA and RC-PREPchelants. The EDTA showed higher cytotoxicity than the RC-PREP to 15min, and that event changed at 30 and 60 minutes. Conclusion: It was shown experimentally that the chelating agents RC-Prep, EDTA and Glyde have a cytotoxic effect at the periodontal ligament fibroblasts. EDTA has a lowest cytotoxic effect at 30 and 60 minutes compared to RC-Prep and Glyde.

Edwin, De la Cruz Rocha; Luisa Paola, Figueredo; Johana, Gómez; Idalith, Jiménez; Ilinka, Montes; Sergio, Roca; Gabriela, Vergel.

2012-12-01

144

Vascular responses in the human periodontal ligament and alveolar bone detected by photoelectric plethysmography: the effect of force application to the tooth.  

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A modification of the technique of photoelectric plethysmography has been developed to monitor changes in the microcirculation of the human periodontal ligament and adjacent alveolar bone, whereby detection is made of light reflected from or transmitted through a tissue during alterations in blood volume, flow or distribution. Light is conducted to and from the periodontal tissues via miniature fiberoptics placed within the root canals of endodontically treated teeth, or illuminated through the external surface of the gingiva towards the root. Circulatory activity was monitored both with the teeth at rest and under forces up to 480 gm. Horizontal and axial forces were found to produce a decrease in blood volume in the area of the periodontal tissue under compression. In an area under tension, an initial increase in blood volume was followed by a decrease as the magnitude of force rose above the critical 90 to 180 gm level. The pulse volume, however, was increased during both phases. Analysis of the biphasic and pulse volume changes suggests that autoregulation of blood vessel tone occurs in the periodontal tissues as a result of alteration in extravascular tissue pressure when the root is moved relative to the alveolus. It is proposed that this autoregulatory mechanism may play a role in alveolar bone metabolism by producing alteration in local tissue oxygen tension. PMID:265385

Packman, H; Shoher, I; Stein, R S

1977-04-01

145

Mechano-transduction in periodontal ligament cells identifies activated states of MAP-kinases p42/44 and p38-stress kinase as a mechanism for MMP-13 expression  

OpenAIRE

Abstract Background Mechano-transduction in periodontal ligament (PDL) cells is crucial for physiological and orthodontic tooth movement-associated periodontal remodelling. On the mechanistic level, molecules involved in this mechano-transduction process in PDL cells are not yet completely elucidated. Results In the present study we show by western blot (WB) analysis and/or indirect immunofluorescence (IIF) that mechanical strain modulates the amount of the matr...

Kohl Annette; Woodnutt Dale; Steinberg Thorsten; Alonso Angel; Ziegler Nelli; Müssig Eva; Schulz Simon; Tomakidi Pascal

2010-01-01

146

Hesperetin alleviates the inhibitory effects of high glucose on the osteoblastic differentiation of periodontal ligament stem cells.  

Science.gov (United States)

Hesperetin (3',5,7-trihydroxy-4-methoxyflavanone) is a metabolite of hesperidin (hesperetin-7-O-rutinoside), which belongs to the flavanone subgroup and is found mainly in citrus fruits. Hesperetin has been reported to be an effective osteoinductive compound in various in vivo and in vitro models. However, how hesperetin effects osteogenic differentiation is not fully understood. In this study, we investigated the capacity of hesperetin to stimulate the osteogenic differentiation of periodontal ligament stem cells (PDLSCs) and to relieve the anti-osteogenic effect of high glucose. Osteogenesis of PDLSCs was assessed by measurement of alkaline phosphatase (ALP) activity, and evaluation of the mRNA expression of ALP, runt-related gene 2 (Runx2), osterix (OSX), and FRA1 as osteogenic transcription factors, as well as assessment of protein expression of osteopontin (OPN) and collagen type IA (COLIA). When PDLSCs were exposed to a high concentration (30 mM) of glucose, osteogenic activity decreased compared to control cells. Hesperetin significantly increased ALP activity at doses of 1, 10, and 100 µM. Pretreatment of cells with hesperetin alleviated the high-glucose-induced suppression of the osteogenic activity of PDLSCs. Hesperetin scavenged intracellular reactive oxygen species (ROS) produced under high glucose condition. Furthermore, hesperetin increased the activity of the PI3K/Akt and ?-catenin pathways. Consistent with this, blockage of Akt or ?-catenin diminished the protective effect of hesperetin against high glucose-inhibited osteogenic differentiation. Collectively, our results suggest that hesperetin alleviates the high glucose-mediated suppression of osteogenic differentiation in PDLSCs by regulating ROS levels and the PI3K/Akt and ?-catenin signaling pathways. PMID:23840726

Kim, So Yeon; Lee, Jin-Yong; Park, Yong-Duk; Kang, Kyung Lhi; Lee, Jeong-Chae; Heo, Jung Sun

2013-01-01

147

The roles of calcium-sensing receptor and calcium channel in osteogenic differentiation of undifferentiated periodontal ligament cells.  

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Elevated extracellular calcium has been shown to promote the differentiation of osteoblasts. However, the way that calcium affects the osteogenic differentiation of human periodontal ligament stem/progenitor cells (PDLSCs) remains unclear. Our aim has been to investigate the proliferation and osteogenic differentiation of a calcium-exposed human PDLSC line (cell line 1-17) that we have recently established and to elucidate the roles of the calcium-sensing receptor (CaSR) and L-type voltage-dependent calcium channel (L-VDCC) in this process. Proliferation activity was investigated by WST-1 assay, and gene and protein expression was examined by quantitative reverse transcriptase plus the polymerase chain reaction and immunostaining, respectively. Calcification assay was performed by von Kossa and Alizarin red staining. Treatment with 5 mM CaCl2 significantly induced proliferation, bone-related gene expression, and calcification in cell line 1-17. During culture with 5 mM CaCl2, this cell line up-regulated the gene expression of CaSR, which was reduced after 7 days. Simultaneous treatment with NPS2143, a CaSR inhibitor, and calcium significantly further increased bone-related gene expression and calcification as compared with CaCl2 exposure alone. The L-VDCC inhibitor, nifedipine, significantly suppressed osteogenic differentiation of cell line 1-17 treated with 5 mM CaCl2 and promoted the expression of CaSR, as compared with calcium treatment alone. Thus, elevated extracellular calcium promotes the proliferation and osteogenic differentiation of a PDLSC line. Antagonizing CaSR further enhances the effect of calcium on osteogenic differentiation, with CaSR expression being regulated by L-VDCC under extracellular calcium. Extracellular calcium might therefore modulate the osteogenic differentiation of PDLSCs through reciprocal adjustments of CaSR and L-VDCC. PMID:24842051

Koori, Katsuaki; Maeda, Hidefumi; Fujii, Shinsuke; Tomokiyo, Atsushi; Kawachi, Giichiro; Hasegawa, Daigaku; Hamano, Sayuri; Sugii, Hideki; Wada, Naohisa; Akamine, Akifumi

2014-09-01

148

Crucial roles of canonical Runx2-dependent pathway on Wnt1-induced osteoblastic differentiation of human periodontal ligament fibroblasts.  

Science.gov (United States)

Canonical Wnt signaling is thought to enhance osteogenic differentiation of human periodontal ligament fibroblasts (hPLFs). However, the mechanism of this enhancement has not yet been defined. We investigated the effects of Wnt1 on osteoblast differentiation of hPLFs and explored the mechanisms of the effects. Treating hPLFs with Wnt1 induced cytosolic accumulation and nuclear translocation of ?-catenin with concomitant increases in alkaline phosphatase (ALP) activity and calcium content in a time-dependent and dose-dependent manner. Wnt1-stimulated differentiation of hPLFs was accompanied by augmented phosphorylation of glycogen synthase kinase (GSK)-3? and expression of the bone-specific factors runt-related transcription factor 2 (Runx2), osterix2 (Osx2), ALP, type I collagen, osteopontin, and osteocalcin. Pretreatment with Dickkopf-1 inhibited Wnt1-stimulated differentiation of hPLFs by suppressing GSK-3? phosphorylation, nuclear translocation of ?-catenin, and expression of the bone-specific factors. Small interfering (si) RNA-mediated knockdown of ?-catenin, or pretreatment with FH535, markedly prevented Wnt1-stimulated differentiation of cells by blocking Runx2 and its downstream factors at the mRNA and protein levels. siRNA-mediated silencing of Runx2 also inhibited Wnt1-stimulated mineralization of cells, accompanied by a reduction in the levels of Osx2 and other early and late bone-formation regulatory factors. However, Wnt1-mediated nuclear translocation of ?-catenin and GSK-3? phosphorylation were not inhibited by knockdown of Runx2 or FH535. Collectively, our findings suggested that Wnt1 stimulates osteogenic differentiation and mineralization of hPLFs, mainly by activating the canonical Wnt/?-catenin pathway, in which Runx2 is a key downstream regulator. PMID:25618247

Kook, Sung-Ho; Heo, Jung Sun; Lee, Jeong-Chae

2015-04-01

149

Essentials in Periodontal Regeneration  

Directory of Open Access Journals (Sweden)

Full Text Available Various materials and techniques have been used in the treatment of periodontal disease to achieve regeneration of lost periodontal tissues including cementum, periodontal ligament (PDL and alveolar bone. The composition, regenerative potential, application and therapeutic characteristics of several regenerative materials have been evaluated in the present study.

F. Haghighati

2007-06-01

150

Cyclic tensile force up-regulates BMP-2 expression through MAP kinase and COX-2/PGE2 signaling pathways in human periodontal ligament cells.  

Science.gov (United States)

Periodontal ligament cells play important roles in the homeostasis of periodontal tissue by mechanical stress derived from mastication, such as tension, compression, fluid shear, and hydrostatic force. In the present study, we showed that cyclic tensile force increased the gene expression level of bone morphogenetic protein (BMP)-2, a crucial regulator of mineralization, in human periodontal ligament cells using real-time PCR. Signaling inhibitors, PD98059/U0126 (extracellular signal-regulated kinase (ERK) inhibitors) and SB203580/SB202190 (p38 inhibitors), revealed that tensile force-mediated BMP-2 expression was dependent on activation of the ERK1/2 and p38 mitogen-activated protein (MAP) kinase pathways. Cyclic tensile force also induced cyclooxygenase-2 (COX-2) gene expression in a manner dependent on ERK1/2 and p38 MAP kinase pathways, and induced prostaglandin E2 (PGE2) biosynthesis. NS-398, a COX-2 inhibitor, significantly reduced tensile force-mediated BMP-2 expression, indicating that PGE2 synthesized by COX-2 may be involved in the BMP-2 induction. The inhibitory effect of NS-398 was completely restored by the addition of exogenous PGE2. However, stimulation with PGE2 alone in the absence of tensile force had no effect on the BMP-2 induction, indicating that some critical molecule(s) other than COX-2/PGE2 may be required for cyclic tensile force-mediated BMP-2 induction. Collectively, the results indicate that cyclic tensile force activates ERK1/2 and p38 MAP kinase signaling pathways, and induces COX-2 expression, which is responsible for the sequential PGE2 biosynthesis and release, and furthermore, mediates the increase in BMP-2 expression at the transcriptional level. PMID:24561081

Suzuki, Risako; Nemoto, Eiji; Shimauchi, Hidetoshi

2014-04-15

151

Synergistic effects of a calcium phosphate/fibronectin coating on the adhesion of periodontal ligament stem cells onto decellularized dental root surfaces.  

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This study aimed to enhance the attachment of periodontal ligament stem cells (PDLSCs) onto decellularized dental root surface using surface coating with fibronectin and/or calcium phosphate (CaP), and to evaluate the activity of PDLSCs attached to a coated dental root surface following tooth replantation. PDLSCs were isolated from five dogs, and the other dental roots were used as a scaffold for carrying PDLSCs, and then assigned to one of four groups according to whether their surface was coated with CaP, fibronectin, or CaP/fibronectin, or left uncoated (control). Fibronectin increased the adhesion of PDLSCs onto dental root surfaces compared to both the control and CaP-coated groups, and simultaneous surface coating with CaP and fibronectin significantly accelerated and increased PDLSC adhesion compared to the fibronectin-only group. On in vivo tooth replantation, functionally oriented periodontal new attachment was observed on the CaP/fibronectin-coated dental roots to which autologous PDLSCs had adhered, while in the control condition dental root replantation was associated only with root resorption and ankylosis along the entire root length. CaP and fibronectin synergistically enhanced the attachment of PDLSCs onto dental root surfaces, and autologous PDLSCs could produce de novo periodontal new attachment in an experimental in vivo model. PMID:25290076

Lee, Jung-Seok; Kim, Hyun-Suk; Park, So-Yon; Kim, Tae-Wan; Jung, Jae-Suk; Lee, Jong-Bin; Kim, Chang-Sung

2014-10-01

152

Ibandronate promotes osteogenic differentiation of periodontal ligament stem cells by regulating the expression of microRNAs  

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Research highlights: {yields} Ibandronate significantly promote the proliferation of PDLSC cells. {yields} Ibandronate enhanced the expression of ALP, COL-1, OPG, OCN, Runx2. {yields} The expression of a class of miRNAs, e.g., miR-18a, miR-133a, miR-141 and miR-19a, was significantly modified in PDLSC cells cultured with ibandronate. {yields} Ibandronate regulates the expression of diverse bone formation-related genes via miRNAs in PDLSCs. {yields} Ibandronate can suppress the activity of osteoclast while promoting the proliferation of osteoblast by regulating the expression of microRNAs. -- Abstract: Bisphosphonates (BPs) have a profound effect on bone resorption and are widely used to treat osteoclast-mediated bone diseases. They suppress bone resorption by inhibiting the activity of mature osteoclasts and/or the formation of new osteoclasts. Osteoblasts may be an alternative target for BPs. Periodontal ligament stem cells (PDLSCs) exhibit osteoblast-like features and are capable of differentiating into osteoblasts or cementoblasts. This study aimed to determine the effects of ibandronate, a nitrogen-containing BP, on the proliferation and the differentiation of PDLSCs and to identify the microRNAs (miRNAs) that mediate these effects. The PDLSCs were treated with ibandronate, and cell proliferation was measured using the MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay. The expression of genes and miRNAs involved in osteoblastic differentiation was assayed using quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). Ibandronate promoted the proliferation of PDLSCs and enhanced the expression of alkaline phosphatase (ALP), type I collagen (COL-1), osteoprotegerin (OPG), osteocalcin (OCN), and Runx2. The expression of miRNAs, including miR-18a, miR-133a, miR-141 and miR-19a, was significantly altered in the PDLSCs cultured with ibandronate. In PDLSCs, ibandronate regulates the expression of diverse bone formation-related genes via miRNAs. The exact mechanism underlying the role of ibandronate in osteoblasts has not been completely understood. Ibandronate may suppress the activity of osteoclasts while promoting the proliferation of osteoblasts by regulating the expression of miRNAs.

Zhou, Qiang [Department of General Dentistry and Emergency, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Zhao, Zhi-Ning [Clinical Laboratory, 451 Hospital of Chinese PLA, Xi' an 710054 (China); Cheng, Jing-Tao [Department of Special Dentistry, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Zhang, Bin [Department of Orthodontics, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Xu, Jie [Department of Periodontology, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Huang, Fei; Zhao, Rui-Ni [Department of General Dentistry and Emergency, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Chen, Yong-Jin, E-mail: cyj1229@fmmu.edu.cn [Department of General Dentistry and Emergency, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China)

2011-01-07

153

Ibandronate promotes osteogenic differentiation of periodontal ligament stem cells by regulating the expression of microRNAs  

International Nuclear Information System (INIS)

Research highlights: ? Ibandronate significantly promote the proliferation of PDLSC cells. ? Ibandronate enhanced the expression of ALP, COL-1, OPG, OCN, Runx2. ? The expression of a class of miRNAs, e.g., miR-18a, miR-133a, miR-141 and miR-19a, was significantly modified in PDLSC cells cultured with ibandronate. ? Ibandronate regulates the expression of diverse bone formation-related genes via miRNAs in PDLSCs. ? Ibandronate can suppress the activity of osteoclast while promoting the proliferation of osteoblast by regulating the expression of microRNAs. -- Abstract: Bisphosphonates (BPs) have a profound effect on bone resorption and are widely used to treat osteoclast-mediated bone diseases. They suppress bone resorption by inhibiting the activity of mature osteoclasts and/or the formation of new osteoclasts. Osteoblasts may be an alternative target for BPs. Periodontal ligament stem cells (PDLSCs) exhibit osteoblast-like features and are capable of differentiating into osteoblasts or cementoblasts. This study aimed to determine the effects of ibandronate, a nitrogen-containing BP, on the proliferation and the differentiation of PDLSCs and to identify the microRNAs (miRNAs) that mediate these effects. The PDLSCs were treated with ibandronate, and cell proliferation was measured using the MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay. The expression of genes and miRNAs involved in osteoblastic differentiation was assayed using quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). Ibandronate promoted the proliferation of PDLSCs and enhanced the expression of alkaline phosphatase (ALP), type I collagen (COL-1), osteoprotegerin (OPG), osteocalcin (OCN), and Runx2. The expression of miRNAs, including miR-18a, miR-133a, miR-141 and miR-19a, was significantly altered in the PDLSCs cultured with ibandronate. In PDLSCs, ibandronate regulates the expression of diverse bone formation-related genes via miRNAs. The exact mechanism underlying the role of ibandronate in osteoblasts has not been completely understood. Ibandronate may suppress the activity of osteoclasts while promoting the proliferation of osteoblasts by regulating the expression of miRNAs.

154

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

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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.

SriramRavindran

2014-01-01

155

Effect of human platelet-derived growth factor-BB on attachment of periodontal ligament cells on root surfaces.  

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Root planing is the most important treatment to make the diseased root surfaces biocompatible to HPLCs adherence. Application of PDGF-BB to root surfaces demineralized with citric acid may be advocated to enhance periodontal regeneration.

Sema Becerik

2009-01-01

156

Effects of hormones and cytokines on stimulation of adenylate cyclase and intracellular calcium concentration in human and canine periodontal-ligament fibroblasts.  

Science.gov (United States)

Adenylate cyclase was stimulated by prostaglandin E2 (PGE2) and parathyroid hormone-related protein (PTHrP) in both these types of fibroblast and by calcitonin gene-related protein (CGRP) in the human fibroblasts in vitro. PGE2 (1 microM), CGRP (1 microM), and PTHrP (1 microM) stimulated adenylate cyclase up to 50-fold, 10-fold and 9-fold, respectively. Calcitonin (CT), substance P (SP), interleukin-1 beta (IL-1 beta), and transforming growth factor-beta 1 (TGF beta 1) had no effect on adenylate cyclase in either fibroblast. Intracellular Ca2+ (iCa2+) was measured in individual fibroblasts from the periodontal ligament using Indo-1 and an adherent cell analysis and sorting interactive laser cytometer. Ionomycin (3 microM) caused a transient rise of iCa2+ in all human and canine fibroblasts tested. The mean percentage increase in iCa2+ in response to ionomycin was 820 and 840% for human and canine fibroblasts, respectively. The human fibroblasts responded to PGE2 (1 microM) by an increased iCa2+ concentration; the mean percentage increase in iCa2+ was 187%. SP caused a less pronounced increase in iCa2+ in the human fibroblasts (56%). CGRP and SP caused a similar response in the canine fibroblasts. The mean percentage increase in iCa2+ in response to SP and CGRP was 95 and 78%, respectively. PTH, PTHrP, platelet-activating factor, CT, and IL-1 beta had no effect on iCa2+ in either type of fibroblast. The data indicate that cAMP and calcium have roles as intracellular secondary messengers in the action of PGE2, SP, CGRP, and PTHrP in fibroblasts of human and canine periodontal ligament. PMID:7506523

Nohutcu, R M; McCauley, L K; Horton, J E; Capen, C C; Rosol, T J

1993-10-01

157

Activation of cannabinoid receptor CB2 regulates LPS-induced pro-inflammatory cytokine production and osteoclastogenic gene expression in human periodontal ligament cells  

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Full Text Available Background and Objective: It has been found that human periodontal ligament (hPDL cells express cannabinoid receptor CB2. However, the functional importance of CB2 in hPDL cells exposed to bacterial endotoxins is not known. Here we investigate if the inflammation promoter lipopolysaccharide (LPS affects CB2 expression and if activation of CB2 regulates LPS-induced pro-inflammatory cytokine production and osteoclastogenic gene expression in hPDL cells. Methods: The hPDL cells were obtained from extracted teeth of periodontally healthy subjects. CB2 expression in hPDL cells exposed to LPS was deter- mined by quantitative real-time PCR analysis. Then, the cells were incubated with or without CB2-specific agonist HU-308 before further stimulation with LPS. In some experiments, the cells were pre-treated with CB2-specific antagonist SR144528. The production of pro-inflammatory cytokines interleukin-1 beta (IL- 1?, interleukin-6 (IL-6 and tumor necrosis factoralpha (TNF-? was assessed by enzyme-linked immunosorbent assay (ELISA. The mRNA expression of osteoclastogenic genes osteoprotegerin (OPG and receptor activator of NF-?B ligand (RANKL was examined using quantitative real-time PCR analysis. Results: CB2 expression in hPDL cells was markedly enhanced by LPS. HU-308 significantly suppressed the production of IL-1?, IL-6 and TNF-? exposed to LPS, whereas SR144528 attenuated this effect. The OPG/RANKL ratio decreased when exposed to LPS, furthermore increased significantly with the addition of HU-308 and finally decreased markedly after pretreatment with SR144528. Conclusion: Our study demonstrated that activation of CB2 had anti-inflammatory and anti-resorptive effects on LPS-stimulated hPDL cells. These findings suggest that activation of CB2 might be an effective therapeutic strategy for the treatment of inflammation and alveolar bone resorption in periodontitis.

Yongming Li

2013-03-01

158

TGF-?-Operated Growth Inhibition and Translineage Commitment into Smooth Muscle Cells of Periodontal Ligament-Derived Endothelial Progenitor Cells through Smad- and p38 MAPK-Dependent Signals  

OpenAIRE

The periodontal ligament (PDL) is a fibrous connective tissue that attaches the tooth to the alveolar bone. We previously demonstrated the ability of PDL fibroblast-like cells to construct an endothelial cell (EC) marker-positive blood vessel-like structure, indicating the potential of fibroblastic lineage cells in PDL tissue as precursors of endothelial progenitor cells (EPCs) to facilitate the construction of a vascular system around damaged PDL tissue. A vascular regeneration around PDL ti...

Yoshida, Mariko; Okubo, Naoto; Chosa, Naoyuki; Hasegawa, Tomokazu; Ibi, Miho; Kamo, Masaharu; Kyakumoto, Seiko; Ishisaki, Akira

2012-01-01

159

Comparación histomorfométrica in vitro del ligamento periodontal de premolares extraídos mantenidos en cuatro medios de conservación / In vitro histomorphometric comparison of periodontal ligament of extracted premolar teeth preserved in different media storage  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish Objetivo: El propósito de este estudio fue evaluar histológica y morfométricamente los resultados de diferentes tipos de medios de almacenamiento para los dientes avulsionados en el mantenimiento de la preservación de la integridad del ligamento periodontal. Material y métodos: Estudio de tipo exper [...] imental de laboratorio, se utilizaron veintitrés premolares extraídos por motivos ortodóncicos. Los medios de conservación evaluados fueron: leche tipo "B" y tipo "C", solución salina y medio seco. Un total de cinco dientes fueron almacenados en cada uno de los medios de conservación durante 120 minutos. Otros tres dientes sirvieron como controles fijados inmediatamente después de la extracción representando el ligamento periodontal íntegro. Los dientes se fijaron, procesaron y tiñeron con hematoxilina y eosina para evaluación histológica a través de microscopia óptica. Resultados: La edad de los pacientes que aportaron los dientes osciló entre 13 a 17 años. Los resultados de la evaluación cualitativa mostraron que la solución fisiológica fue el medio de almacenamiento más adecuado seguido de la leche tipo C y tipo B. En el análisis estadístico no hubo diferencia estadísticamente significativa entre los grupos de solución fisiológica y leche tipo C. Después de 120 minutos se encontraron diferencias estadísticamente significativas entre las alteraciones histomorfométricas del grupo control y los grupos de dientes que se mantuvieron en condiciones de humedad y los secos. Conclusión: Dados los resultados de este estudio, la solución salina (grupo II) y la leche tipo C (Grupo III) pueden considerarse como las formas de conservación más adecuadas de los dientes avulsionados. Abstract in english Objective: The aim of this study was to histologically and morphometrically evaluate the results of different types of storage media for avulsed teeth in the maintenance and preserving the integrity of the periodontal ligament. Material and methods: Experimental study. It was used twenty-three extra [...] cted premolars for orthodontic reasons. Preserving methods evaluated were: type "B" and "C" milk, saline and dry environment. A total of five teeth were stored in each storage media for 120 minutes. Three teeth served as controls fixed immediately after extraction representing the entire periodontal ligament. The teeth were fixed, processed and stained with hematoxylin/eosin for histological evaluation by light microscopy. Results: The age of the patients who provided the teeth ranged from 13-17 years. The results of the qualitative assessment showed that saline was the most appropriate storage medium, followed by milk type C and type B. In the statistical analysis there was no statistically significant difference between saline and type C milk. After 120 minutes it was found statistically significant differences between histomorphometric changes in the control group and groups of teeth that were kept in wet conditions and dry. Conclusion: Given the results of this study, saline (group II) and milk type C (Group III) can be considered as the most suitable form of storage of avulsed teeth.

I., Prokopowitsch; R., Cabrales Salgado; A., Díaz Caballero; M., Simancas Pallares.

2013-04-01

160

The Effect of Propolis As A Biological Storage Media on Periodontal Ligament Cell Survival in An Avulsed Tooth: An In Vitro Study  

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Objective: Both the length of extra-alveolar time and type of storage media are significant factors that can affect the long-term prognosis of replanted teeth. This study aims to compare propolis 50%, propolis 10%, Hank’s balanced salt solution (HBSS), milk and egg white on periodontal ligament (PDL) cell survival for different time points. Materials and Methods: : In this in vitro experimental study, we divided 60 extracted teeth without any periodontal diseases into five experimental and two control groups that consisted each experimental group with 10 and each control group with 5 teeth. The storage times were one and three hours for each media. The controls corresponded to 0-minute (positive) and 12-hour (negative) dry time. Rinsing in the experimental media, the teeth were treated with dispase and collagenase for one hour. Cell viability was determined by using trypan blue exclusion. Statistical analysis of the data was accomplished by using two-way analysis of variance (ANOVA) complemented by the Tukey’s HSD post-hoc. Results: Within one hour, there was no significant difference between the two propolis groups, however these two groups had significantly more viable PDL cells compared to the other experimental media (p<0.05). The results of the three-hour group showed that propolis 10% was significantly better than egg white, whereas both propolis 10% and 50% were significantly better than milk (p<0.05). Conclusion: Based on PDL cell viability, propolis could be recommended as a suitable biological storage media for avulsed teeth. PMID:24027666

Ahangari, Zohreh; Alborzi, Samiye; Yadegari, Zahra; Dehghani, Fatemeh; Ahangari, Leila; Naseri, Mandana

2013-01-01

161

The Effect of Propolis As A Biological Storage Media on Periodontal Ligament Cell Survival in An Avulsed Tooth: An In Vitro Study  

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Full Text Available Objective: Both the length of extra-alveolar time and type of storage media are significant factors that can affect the long-term prognosis of replanted teeth. This study aims to compare propolis 50%, propolis 10%, Hank’s balanced salt solution (HBSS, milk and egg white on periodontal ligament (PDL cell survival for different time points.Materials and Methods: In this in vitro experimental study, we divided 60 extracted teeth without any periodontal diseases into five experimental and two control groups that consisted each experimental group with 10 and each control group with 5 teeth. The storage times were one and three hours for each media. The controls corresponded to 0-minute (positive and 12-hour (negative dry time. Rinsing in the experimental media, the teeth were treated with dispase and collagenase for one hour. Cell viability was determined by using trypan blue exclusion. Statistical analysis of the data was accomplished by using two-way analysis of variance (ANOVA complemented by the Tukey’s HSD post-hoc.Results: Within one hour, there was no significant difference between the two propolis groups, however these two groups had significantly more viable PDL cells compared to the other experimental media (p<0.05. The results of the three-hour group showed that propolis 10% was significantly better than egg white, whereas both propolis 10% and 50% were significantly better than milk (p<0.05.Conclusion: Based on PDL cell viability, propolis could be recommended as a suitable biological storage media for avulsed teeth.

Leila Ahangari

2013-01-01

162

Stem cells for periodontal regeneration.  

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Periodontal regeneration is considered to be biologically possible but clinically unpredictable. In periodontitis, inflammation manifests clinically as loss of supporting periodontal tissues and regeneration of damaged tissue is the main goal of treatment. For decades, periodontists have sought to repair the damage through a variety of surgical procedures, and use of grafting materials and growth factors, and of barrier membranes. Reports have emerged that demonstrate which populations of adult stem cells reside in the periodontal ligaments of humans and other animals. This opens the way for new cell-based therapies for periodontal regeneration. This review provides an overview of adult human stem cells and their potential use in periodontal regeneration. PMID:24265588

Pejcic, A; Kojovic, D; Mirkovic, D; Minic, I

2013-06-01

163

Remoción del ligamento periodontal por medio de fricción con gasa embebida en solución de hipoclorito de sodio a 1% / Periodontal ligament remotion using friction of sodium hypochloride 1% solution absorbed gauze  

Scientific Electronic Library Online (English)

Full Text Available SciELO Venezuela | Language: Spanish Abstract in portuguese Sabe-se que o hipoclorito de sódio pode remover o ligamento periodontal desvitalizado em dentes avulsionados. Adequações em seu uso se mostram necessárias para se obter um reparo mais satisfatório em dentes reimplantados. Portanto, estudou-se neste trabalho a capacidade de remoção do ligamento perio [...] dontal, por meio de fricção da superfície radicular de dentes de rato, com uma gaze embebida em solução de hipoclorito de sódio a 1%. Foram utilizados 40 dentes divididos em 4 grupos de 10, os quais após a extração, foram mantidos em meio seco por 60 minutos. No grupo controle, os dentes foram mantidos em 25ml de hipoclorito de sódio a 1% por 5 minutos. No grupo II, a superfície radicular foi friccionada com gaze embebida em 25ml de solução de hipoclorito de sódio a 1% por um período de 1 minuto e na seqüência lavados em soro fisiológico por 4 minutos. No grupo III, a fricção foi de 2 minutos, e o período de lavagem foi de 3 minutos. No grupo IV, a fricção foi de 4 minutos e o período de lavagem foi de 1 minuto. Após o processamento laboratorial, os cortes foram corados pelo Tricrômico de Masson e pela hematoxilina e eosina para análise histomorfométrica. Os resultados demonstraram que no grupo controle, 100% da superfície radicular estava coberta por ligamento periodontal. Mediante o teste de proporção, observou-se que a fricção por 1 minuto foi menos eficaz, sendo estatisticamente significante (p Abstract in spanish Estudios han demostrado la capacidad del hipoclorito de sodio en la remoción del ligamento periodontal sin vitalidad en dientes avulsionados. Sin embargo el uso de esta sustancia puede ocasionar un efecto irritante en el tejido conjuntivo. Siendo así adecuaciones en su utilización se muestran necesa [...] rias para que se obtenga un reparo más satisfactorio cuando utilizados en dientes reimplantados. Por lo tanto es propuesta de ese estudio evaluar la capacidad de remoción del ligamento periodontal, por medio de fricción de la superficie radicular de dientes de ratones, con una gasa humedecida en solución de hipoclorito de sodio al 1%. Fueron utilizados 40 dientes divididos en 4 grupos de 10, los cuales después de la extracción, fueron mantenidos en medio seco por 60 minutos. En el grupo control, los dientes fueron mantenidos en 25ml de hipoclorito de sodio a 1% por 5 minutos. En el grupo II, la superficie radicular fue friccionada con gasa humedecida en 25ml de solución de hipoclorito de sodio a 1% por un periodo de 1 minuto y en la secuencia lavados en suero fisiológico por 4 minutos. En el grupo III, la fricción fue de 2 minutos, y el periodo del lavado 2 minuto. En el grupo IV, la fricción con 4 minutos y el periodo del lavado 1 minuto. Después del procesamiento laboratorial, los cortes obtenidos fueron coloreados por el Tricromio de Masson y Hematoxilina y eosina para análisis en microscopia de luz. Los resultados demostraron que en el grupo control 100% de la superficie radicular estaba cubierto por ligamento periodontal. A través del test de proporción, se observó que la fricción por 1 minuto fue menos eficaz, con diferencia estadísticamente significante (p Abstract in english Studies have demonstrated the capacity of the sodium hypochloride in removing the non-vital periodontal ligament in avulsed tooth. Adequacies in its use are necessary to get a repair more satisfactory when teeth are replanted. Therefore, the purpose of this study was to evaluated the capacity of rem [...] oval the periodontal ligament in root surface of rats, using friction of sodium hypochloride 1% solution absorbed gauze. Forty teeth were divided in 4 groups with 10 teeth, which after the extration, had been kept in dry way per 60 minutes. In control group, the teeth had been kept in 25ml of sodium hypochloride 1% for 5 minutes. In group II, the root surface was rubbed with in 25ml of sodium hypochloride 1% solution absorbed gauze for 1 minute and rinsed for 4 minutes in saline. In group

Celso, Koogi Sonoda; Wilson, Roberto Poi; Sônia, Regina Panzarini; Maria Lúcia, Marçal Mazza Sundfeld; Fernando, Esgaib Kayatt; Tetuo, Okamoto.

164

Effect of CTGF/CCN2 on osteo/cementoblastic and fibroblastic differentiation of a human periodontal ligament stem/progenitor cell line.  

Science.gov (United States)

Appropriate mechanical loading during occlusion and mastication play an important role in maintaining the homeostasis of periodontal ligament (PDL) tissue. Connective tissue growth factor (CTGF/CCN2), a matricellular protein, is known to upregulate extracellular matrix production, including collagen in PDL tissue. However, the underlying mechanisms of CTGF/CCN2 in regulation of PDL tissue integrity remain unclear. In this study, we investigated the effect of CTGF/CCN2 on osteo/cementoblastic and fibroblastic differentiation of human PDL stem cells using the cell line 1-11. CTGF/CCN2 expression in rat PDL tissue and human PDL cells (HPDLCs) was confirmed immunohisto/cytochemically. Mechanical loading was found to increase gene expression and secretion of CTGF/CCN2 in HPDLCs. CTGF/CCN2 upregulated the proliferation and migration of 1-11 cells. Furthermore, increased bone/cementum-related gene expression in this cell line led to mineralization. In addition, combined treatment of 1-11 cells with CTGF/CCN2 and transforming growth factor-?1 (TGF-?1) significantly promoted type I collagen and fibronectin expression compared with that of TGF-?1 treatment alone. Thus, these data suggest the underlying biphasic effects of CTGF/CCN2 in 1-11 cells, inducible osteo/cementoblastic, and fibroblastic differentiation dependent on the environmental condition. CTGF/CCN2 may contribute to preservation of the structural integrity of PDL tissue, implying its potential use as a therapeutic agent for PDL regeneration. PMID:24905848

Yuda, Asuka; Maeda, Hidefumi; Fujii, Shinsuke; Monnouchi, Satoshi; Yamamoto, Naohide; Wada, Naohisa; Koori, Katsuaki; Tomokiyo, Atsushi; Hamano, Sayuri; Hasegawa, Daigaku; Akamine, Akifumi

2015-01-01

165

Novel application of human periodontal ligament stem cells and water-soluble chitin for collagen tissue regeneration: in vitro and in vivo investigations.  

Science.gov (United States)

Human periodontal ligament stem cells (hPDLSCs) have been proposed as an alternative to conventional cosmetic fillers because they display an innate ability to synthesize collagen. The aims of this study were to determine the effects of water-soluble chitin (WSC) on the proliferation and migration of hPDLSCs, and to quantify collagen synthesis in vitro and in vivo compared with human adipose-derived stem cell (hADSC)s. hPDLSCs were isolated from healthy extracted teeth, and the cell proliferation and cell migration capacities of untreated hPDLSCs (control group) and WSC-treated hPDLSCs (test group) were compared. Insoluble/soluble collagen synthesis were also assessed, and collagen related markers were evaluated including lysyl oxidase (LOX), lysyl oxidase like (LOXL)1, LOXL2, and hydroxyproline. In vivo collagen formation was examined by transplanting hyaluronic acid as a cell carrier into the subcutaneous pockets of immunocompromised mice in the control and test groups; histology and immunohistochemistry analyses were performed 4 (n=4) and 8 (n=4) weeks later. There was a dose-dependent enhancement of hPDLSCs proliferation in the test group, and a concomitant reduction in cell migration. The amount of insoluble collagen formed was greater in the test group than in the control group (pcosmetic soft-tissue augmentation. PMID:21981356

Jung, Im Hee; Park, Jung Chul; Kim, Jane C; Jeon, Dong Won; Choi, Seong Ho; Cho, Kyoo Sung; Im, Gun Il; Kim, Byung Soo; Kim, Chang Sung

2012-03-01

166

Engineering the Periodontal Ligament in Hyaluronan-Gelatin-Type I Collagen Constructs: Upregulation of Apoptosis and Alterations in Gene Expression by Cyclic Compressive Strain.  

Science.gov (United States)

To engineer constructs of the periodontal ligament (PDL), human PDL cells were incorporated into a matrix of hyaluronan, gelatin, and type I collagen (COLI) in sample holders (13×1?mm) of six-well Biopress culture plates. The loading dynamics of the PDL were mimicked by applying a cyclic compressive strain of 33.4?kPa (340.6 gm/cm(2)) to the constructs for 1.0?s every 60?s, for 6, 12, and 24?h in a Flexercell FX-4000C Strain Unit. Compression significantly increased the number of nonviable cells and increased the expression of several apoptosis-related genes, including initiator and executioner caspases. Of the 15 extracellular matrix genes screened, most were upregulated at some point after 6-12?h deformation, but all were downregulated at 24?h, except for MMPs1-3 and CTGF. In culture supernatants, matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinases-1 (TIMP-1) protein levels were upregulated at 24 h; receptor activator of nuclear kappa factor B (RANKL), osteoprotegerin (OPG) and fibroblast growth factor-2 (FGF-2) were unchanged; and connective tissue growth factor (CTGF) not detected. The low modulus of elasticity of the constructs was a disadvantage-future mechanobiology studies and tissue engineering applications will require constructs with much higher stiffness. Since the major structural protein of the PDL is COLI, a more rational approach would be to permeabilize preformed COLI scaffolds with PDL-populated matrices. PMID:25181942

Saminathan, Aarthi; Sriram, Gopu; Vinoth, Jayasaleen Kumar; Cao, Tong; Meikle, Murray C

2014-10-01

167

Activation of focal adhesion kinase induces extracellular signal-regulated kinase-mediated osteogenesis in tensile force-subjected periodontal ligament fibroblasts but not in osteoblasts.  

Science.gov (United States)

The exact mechanism by which focal adhesion kinase (FAK) translates mechanical signals into osteogenesis differentiation in force-subjected cells has not been elucidated. The responses to different forces differ according to the origin of cells and the type of stress applied. Therefore, the recruitment of osteoclast and osteoblast progenitor cells, and the balanced activation of these cells around and within the periodontal ligament (PDL) are essential for alveolar bone remodeling. Cells within the PDL and MG63 cells were subjected to tensile forces of -100 kPa for different periods of time. At various times during the tensile force application, they were processed for the purpose of analyzing cell viability, cell cycle, and osteogenic protein. The effect of small interfering RNA transfection targeting FAK was also evaluated. Tensile force enhanced a rapid increase in the phosphorylation of FAK and up-regulated osteogenic protein expression in PDL cells, but not in MG63 cells. Transfecting PDL cells with FAK antisense oligonucleotide diminished alkaline phosphatase and osteocalcin secretion. These findings suggest that tensile force activates FAK pathways in PDL cells, which down-regulate immune cytokine and up-regulate osteogenic protein. PMID:24362490

Chen, Yi-Jyun; Shie, Ming-You; Hung, Chi-Jr; Wu, Buor-Chang; Liu, Shiau-Lee; Huang, Tsui-Hsien; Kao, Chia-Tze

2014-11-01

168

Effects of the ?-adrenoceptor antagonists phentolamine, phenoxybenzamine, and Idazoxan on sympathetic blood flow control in the periodontal ligament of the cat  

International Nuclear Information System (INIS)

Blood flow changes in the periodontal ligament (PDL) were measured indirectly by monitoring the local clearance of 125I- during electric sympathetic nerve stimulation or close intra-arterial infusions of either noradrenaline (NA) or adrenaline (ADR) before and after administration of phentolamine (PA), phenoxybenzamine (PBZ) or Idazoxan (RX). At the doses used in the present study, PA was the only antagonist that significantly reduced the blood flow decrease seen on activation of sympathetic fibers, although PBZ also reduced this response. Idazoxan, however, did not induce the consistent effect on blood flow decreases seen on sympathetic activation. All three ?-adrenoceptor antagonists almost abolished the effects of exogenously administered NA and ADR. The results suggest the presence of functional post-junctional adrenoceptors of both the ? 1 and ? 2 subtypes in the sympathetic regulation of the blood flow in the PDL of the cat. A component of the response elicited by electrical sympathetic stimulation appeared to be resistant to ?-adrenoceptor blockade. Administration of guanethidine (which inhibits further release of NA and neuropeptide Y) after PA abolished this residual sympathetic response

169

Rare Periodontal Ligament Drainage for Periapical Inflammation of an Adjacent Tooth: A Case Report and Review of the Literature  

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Aim. To report a case with an unusual drainage route of periapical inflammation exiting through the gingival sulcus of an adjacent vital tooth and review probable factors determining the diversity of the discharge routes of periapical inflammation. Summary. An 18-year-old male patient presented with periodontal abscess of tooth 46, which was found to be caused by a periapical cyst with an acute abscess of tooth 45. During endodontic surgery, a rarely reported drainage route for periapical inflammation via the gingival sulcus of an adjacent vital tooth was observed for the first time. Complete periodontal healing of the deep pocket of tooth 46 and hiding of the periapical cyst of tooth 45 followed after root canal treatment and periapical surgery with Bio-Oss Collagen implantation on tooth 45. The drainage routes of periapical inflammation are multivariate and the diversity of drainage pathways of periapical inflammation is mainly related to factors such as gravity, barriers against inflammation, and the causative tooth itself. PMID:25587462

Guo, Hongmei; Lu, Wei; Han, Qianqian; Li, Shubo; Yang, Pishan

2014-01-01

170

Fighting for territories: time-lapse analysis of dental pulp and dental follicle stem cells in co-culture reveals specific migratory capabilities  

OpenAIRE

Stem cell migration is a critical step during the repair of damaged tissues. In order to achieve appropriate cell-based therapies for tooth and periodontal ligament repair it is necessary first to understand the dynamics of tissue-specific stem cell populations such as dental pulp stem cells (DPSC) and dental follicle stem cells (DFSC). Using time-lapse imaging, we analysed migratory and proliferative capabilities of these two human stem cell lines in vitro. When cultured alone, both DPSC and...

Schiraldi, C.; Stellavato, A.; D’agostino, A.; Tirino, V.; D’aquino, R.; Woloszyk, A.; Rosa, A.; Laino, L.; Papaccio, G.; Ta, Mitsiadis

2012-01-01

171

Effects of calcium phosphate endodontic sealers on the behavior of human periodontal ligament fibroblasts and MG63 osteoblast-like cells.  

Science.gov (United States)

In regard to biological properties of endodontic sealers, there are many characteristics that should be considered. The aim of this study was to examine the biological effects of new calcium phosphate-based root canal sealers, CAPSEAL I and CAPSEAL II (CPS), on human periodontal fibroblast cells by examining the expression levels of inflammatory mediators and to compare the effects of CPS on the viability and osteogenic potential of human osteoblast MG63 cells compared to those of other commercially available calcium phosphate sealers [Apatite Root Sealer type I (ARS I) and Apatite Root Sealer III (ARS III); Sankin Kogyo, Tokyo, Japan] and a zinc oxide eugenol-based sealer (Pulp Canal Sealer EWT [PCS EWT]; Kerr, Detroit, MI). The levels of IL-6 in the new CPS group (CAPSEAL I, II) were higher than those in the control and all experimental groups at all time points after 2 h. TGF-?1 and FGF-1 levels decreased at 72 h compared to the levels in the control, in cells treated with every sealers except ARS I. The new CPS sealers showed low cytotoxicity. Reverse transcription polymerase chain reaction showed that CAPSEAL I, II, and Apatite Root Sealer type III induced expression of early stage markers of differentiation (alkaline phosphatase and osteopontin) at 7 days. Also, new CPS showed higher mineralized nodule formation at 28 days. These results suggest that CAPSEAL I and II facilitate the periapical dentoalveolar and alveolar healing by controlling cellular mediators from PDL cells and osteoblast differentiation of precursor cells. PMID:22848036

Shon, Won-Jun; Bae, Kwang-Shik; Baek, Seung-Ho; Kum, Kee-Yeon; Han, Ah-Reum; Lee, Woo-Cheol

2012-11-01

172

Effects of composite films of silk fibroin and graphene oxide on the proliferation, cell viability and mesenchymal phenotype of periodontal ligament stem cells.  

Science.gov (United States)

In regenerative dentistry, stem cell-based therapy often requires a scaffold to deliver cells and/or growth factors to the injured site. Graphene oxide (GO) and silk fibroin (SF) are promising biomaterials for tissue engineering as they are both non toxic and promote cell proliferation. On the other hand, periodontal ligament stem cells (PDLSCs) are mesenchymal stem cells readily accessible with a promising use in cell therapy. The purpose of this study was to investigate the effects of composite films of GO, SF and GO combined with fibroin in the mesenchymal phenotype, viability, adhesion and proliferation rate of PDLSCs. PDLSCs obtained from healthy extracted teeth were cultured on GO, SF or combination of GO and SF films up to 10 days. Adhesion level of PDSCs on the different biomaterials were evaluated after 12 h of culture, whereas proliferation rate of cells was assessed using the MTT assay. Level of apoptosis was determined using Annexin-V and 7-AAD and mesenchymal markers expression of PDLSCs were analyzed by flow cytometry. At day 7 of culture, MTT experiments showed a high rate of proliferation of PDLSCs growing on GO films compared to the other tested biomaterials, although it was slightly lower than in plastic (control). However PDLSCs growing in fibroin or GO plus fibroin films showed a discrete proliferation. Importantly, at day 10 of culture it was observed a significant increase in PDLSCs proliferation rate in GO films compared to plastic (P cell viability in GO even better than obtained in plastic. Our findings suggest that the combination of human dental stem cells/fibroin/GO based-bioengineered constructs have strong potential for their therapeutic use in regenerative dentistry. PMID:25081645

Rodríguez-Lozano, F J; García-Bernal, D; Aznar-Cervantes, S; Ros-Roca, M A; Algueró, M C; Atucha, N M; Lozano-García, A A; Moraleda, J M; Cenis, J L

2014-12-01

173

PREVALENSI PENYAKIT PERIODONTAL DI KECAMATAN PALU BARAT PADA TAHUN 2013  

OpenAIRE

Latar Belakang: Penyakit periodontal adalah penyakit yang menyebabkan inflamasi pada jaringan penyangga gigi yang di sebabkan oleh mikroorganisme dan menimbulkan kerusakan yang bersifat progresif pada ligament periodontal dan tulang alveolar, yang pada akhirnya akan menimbulkan poket, resesi, maupun keduanya. Ada dua bentuk penyakit periodontal yaitu gingivitis dan periodontitis.Berdasarkan hasil survey di kecamatan Palu Barat, belum ada penelitian yang menggambarkan tentang prevalensi penyak...

RAHMAYANTI

2013-01-01

174

Advanced tissue engineering in periodontal Regeneration  

OpenAIRE

The old wishes of people were to regenerate lost tissues of periodontium that this fact is achieved by gen and cell therapy .Periodontal disease is a chronic inflammation around the tooth by microbes that causes destruction of supporting structure of tissue of tooth such as alveolar bone, cementum and periodontal ligament. For treatment of periodontal diseases we can use the biomaterials which help to regenerate the periodontal tissues like; autogenous bone grafts, allograft, guided tissue re...

Seyed Ali Banihashemrad

2014-01-01

175

Periodontal therapy for severe chronic periodontitis with periodontal regeneration and different types of prosthesis.  

Science.gov (United States)

We report a patient with severe chronic periodontitis requiring regenerative periodontal surgery and different types of prosthesis in the maxillary and mandibular regions. The patient was a 57-year-old woman who presented with the chief complaint of occlusal pain. An initial clinical examination revealed that 73% of sites had a probing depth of ?4 mm, and 60% of sites exhibiting bleeding on probing. Radiographic examination revealed vertical bone defects in the molar region and widening of the periodontal ligament space around teeth #17 and 24. Initial periodontal therapy was implemented based on a clinical diagnosis of severe chronic periodontitis. Surgical periodontal therapy was subsequently performed at selected sites. Periodontal regenerative therapy using enamel matrix derivative was performed on #14, 15, and 35-37. Tunnel preparation was performed on #46 as it had a 2-wall vertical bony defect and Degree 3 furcation involvement. Other sites with residual periodontal pockets were treated by modified Widman flap surgery. After a re-evaluation, functional rehabilitation was implemented with a removable maxillary partial denture and a fixed mandibular bridge. No further deterioration was observed in the periodontal condition of most of the teeth during a 2-year period of supportive periodontal therapy (SPT). The patient is currently still undergoing SPT and some minor problems remain. However, the results suggest that treatment and subsequent maintenance for severe periodontitis with traumatic occlusion can be successful as long as the appropriate periodontal and prosthodontic treatment is planned and careful SPT carried out. PMID:25477039

Kinumatsu, Takashi; Umehara, Kazuhiro; Nagano, Kyosuke; Saito, Atsushi

2014-01-01

176

Histometric analysis of ligature-induced periodontitis in rats: a comparison of histological section planes  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The purpose of this study was to analyze the histometry of ligature-induced periodontitis in rats at different histological section depths. Sixteen male adult Wistar rats were randomly assigned to two groups: ligature and control. In the ligature group, rats received a sterile 4/0 silk ligature arou [...] nd the maxillary right 2nd molar. Thirty serial sections containing the 1st and 2nd molars, in which the coronal and root pulp, cementoenamel junction (CEJ) in the mesial side of the 2nd molar, interproximal alveolar bone and connective fiber attachment were clearly visible, were selected for histometric analysis. The histological sections were clustered in groups of 10 sections corresponding the buccal (B), central (C) and lingual (L) regions of the of periodontal tissue samples. The distance between the CEJ in the mesial side of the 2nd molar and the attached periodontal ligament fibers (CEJ-PL) as well as the distance between the CEJ and the alveolar bone crest (CEJ-BC) were determined. From CEJ-PL and CEJ-BC distances measured for each specimen, the measurements obtained in the B, L and C regions were recorded individually and together. Data were submitted to statistical analysis. Significant differences (p0.05). In conclusion, the selection of 10 serial sections of the central region of periodontal tissue samples at any depth can be considered as representative for the evaluation of periodontal ligament fiber attachment and bone loss in ligature-induced periodontitis in rats.

Tereza Aparecida Delle Vedove, Semenoff; Alex, Semenoff-Segundo; Álvaro Francisco, Bosco; Maria José Hitomi, Nagata; Valdir Gouveia, Garcia; Eder Ricardo, Biasoli.

2008-08-01

177

An investigation of dentinal fluid flow in dental pulp during food mastication: simulation of fluid-structure interaction.  

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This study uses fluid-structure interaction (FSI) simulation to investigate the relationship between the dentinal fluid flow in the dental pulp of a tooth and the elastic modulus of masticated food particles and to investigate the effects of chewing rate on fluid flow in the dental pulp. Three-dimensional simulation models of a premolar tooth (enamel, dentine, pulp, periodontal ligament, cortical bone, and cancellous bone) and food particle were created. Food particles with elastic modulus of 2,000 and 10,000 MPa were used, respectively. The external displacement loading (5 ?m) was gradually directed to the food particle surface for 1 and 0.1 s, respectively, to simulate the chewing of food particles. The displacement and stress on tooth structure and fluid flow in the dental pulp were selected as evaluation indices. The results show that masticating food with a high elastic modulus results in high stress and deformation in the tooth structure, causing faster dentinal fluid flow in the pulp in comparison with that obtained with soft food. In addition, fast chewing of hard food particles can induce faster fluid flow in the pulp, which may result in dental pain. FSI analysis is shown to be a useful tool for investigating dental biomechanics during food mastication. FSI simulation can be used to predict intrapulpal fluid flow in dental pulp; this information may provide the clinician with important concept in dental biomechanics during food mastication. PMID:23913183

Su, Kuo-Chih; Chuang, Shu-Fen; Ng, Eddie Yin-Kwee; Chang, Chih-Han

2014-06-01

178

Análisis de la acción del ácido cítrico en la remoción del Ligamento periodontal necrosado de dientes de ratón / The citric acid action's in the removal of the delayed periodontal ligament of mouse teeth's. / Análise da ação do ácido cítrico na remoção do ligamento periodontal necrosado de dentes de rato  

Scientific Electronic Library Online (English)

Full Text Available SciELO Venezuela | Language: Spanish Abstract in portuguese A manutenção do ligamento periodontal sem vitalidade sobre a superfície radicular pode influenciar no processo de reparo no reimplante dentário, pois pode ser substituído por tecido ósseo ou dar início a um processo de reabsorção inflamatória. Por isso, muitas formas de remoção desse ligamento têm s [...] ido estudadas. É propósito de este trabalho avaliar, por meio de cortes histológicos, os resultados do tratamento da superfície de dentes avulsionados cirurgicamente e deixados em meio ambiente por 6 horas com soro fisiológico e ácido cítrico (pH 1.0). Para a realização do experimento serão empregados 15 ratos, divididos em três grupos, com 5 dentes em cada: Grupo I, soro fisiológico por três minutos; Grupo II, ácido cítrico (pH 1.0) por três minutos e; Grupo III, fricção da superfície radicular com gaze estéril umedecida com ácido cítrico (pH 1.0) por um minuto. Após o processamento laboratorial de rotina os cortes foram submetidos à análise qualitativa e quantitativa (Software ImageLab - Diracom 3). Em todos os grupos foram observados remanescentes do ligamento periodontal em toda extensão palatina da superfície radicular. O grupo III mostrou maior área de tecido com diferença estatisticamente significante (p> 0.001). Foi possível concluir que o ácido cítrico não foi capaz de remover o ligamento periodontal necrosado de dentes de rato após seis horas de ressecamento, em nenhuma das formas de aplicação utilizada. Abstract in spanish El mantenimiento del ligamento periodontal sin vitalidad en la superficie radicular puede influenciar en el proceso de reparación en el reimplante dental, por lo tanto puede ser sustituido por tejido óseo o comenzar un proceso de reabsorción inflamatória. Por lo tanto, muchas formas de retiro de est [...] e ligamento se han estudiado. Es propuesta de ese trabajo evaluar, por medio de cortes histológicos, los resultados del tratamiento de la superficie de los dientes sometidos a exodoncias y mantenerlo en medio ambiente por 6 horas. Para la realización del experimiento, se utilizaron 15 ratones, divididos en tres grupos, con 5 dientes cada uno: Grupo I, suero fisiológico por tres minutos; Grupo II, ácido cítrico (pH 1.0) por tres minutos; Grupo III, fricción de la superficie radicular con gaza esteril humedecida con ácido cítrico (pH1.0) por um minuto. Después del procesamiento laboratorial de rutina los cortes fueron sometidos a análisis cuantitativo y cualitativo (Software ImageLab - Diracom 3). En todos los grupos fueron observados restos del ligamento periodontal en toda la extensión palatina de la superfície radicular. El grupo III tuvo la mayor área de tejido con diferencia estadisticamente significante (p> 0.001). Fue posible concluir que el ácido cítrico no fue capaz de remover el ligamento periodontal necrosado de dientes de ratón después de seis horas de resequedad, en ninguna de las formas de aplicación utilizada. Abstract in english The maintenance of the periodontal ligament without vitality on the root surface can influence in the process of repair in the dental replantation, therefore it can be substituted by bone tissue or to give beginning to a process of inflammatory resorption. Therefore, many forms of removal of this li [...] gament have been studied. It is intention of this work to evaluate, by means of histological study, the results of the treatment of the tooth surface in dental extraction and left in environment for 6 hours. For the accomplishment of the experiment 15 mouse, divided in three groups will be used, with 5 teeth in each: Group I, salt solution per three minutes; Group II, acid citric (pH 1,0) per three minutes e; Group III, friction of the root surface with acid humidified barren gauze with citric (pH 1,0) per one minute. After the laboratorial processing of routine the cuts had been submitted to the qualitative and quantitative analysis (Software ImageLab - Diracom 3). In all the groups had been observed

Wilson Roberto, Poi; Ellen, Greves Giovanini; Luciana, Estevam Simonato; Thaís, Mara Manfrin; Fernando, Esgaib Kayatt; Sônia, Regina Panzarini.

179

Multifactorial relationship of obesity and periodontal disease.  

Science.gov (United States)

Obesity is a chronic disease of mutifactorial origin, where there is increase in body fat. Periodontitis is an inflammatory disease of tooth supporting tissues resulting in destruction of periodontal ligament and alveolar bone. Periodontitis and obesity are both chronic health problems and the literature supports this association. A hyperinflammatory state observed in obesity is proposed as a mechanism to explain this association. This low grade inflammation in obese subjects triggers the worsening of non transmissible chronic diseases like periodontitis. So the aim of this article is to get the overview of association between adipose tissue derived cytokines and periodontal disease. PMID:24959524

Suresh, Snophia; Mahendra, Jaideep

2014-04-01

180

Critical analysis of biomarkers in the current periodontal practice  

OpenAIRE

Periodontal disease is a chronic microbial infection that triggers inflammation-mediated loss of the periodontal ligament and alveolar bone that supports the teeth. Because of the increasing prevalence and associated comorbidities, there is a need for the development of new diagnostic tests that can detect the presence of active disease, predict future disease progression, and evaluate the response to periodontal therapy, thereby improving the clinical management of periodontal patients. The ...

Khiste, Sujeet V.; Ranganath, V.; Nichani, Ashish S.; Rajani, V.

2011-01-01

181

Analysis of the dentin-pulp complex in teeth submitted to orthodontic movement in rats  

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Full Text Available In order to microscopically analyze the pulpal effects of orthodontic movement, 49 maxillary first molars of rats were submitted to orthodontic appliance composed of a closed coil spring anchored to the maxillary incisors, placed for the achievement of mesial movement. MATERIAL AND METHODS: Ten animals were used as the control group and were not submitted to orthodontic force; the other animals were divided into groups according to the study period of tooth movement, namely 1, 2, 3, 4, 5, 6 and 7 days. The investigation of pulp and periodontal changes included hyalinization, fibrosis, reactive dentin and vascular congestion. Statistical evaluation was performed between control and experimental groups and between periods of observation using non-parametric chi-square, Kruskal-Wallis and Dunn tests. RESULTS: There was no statistically significant difference concerning pulpal changes between control and experimental groups nor between periods of observation. The control group, at 3 and 5 days, revealed greater hyalinization of the periodontal ligament (p<0.05, whereas root resorption was significantly greater at 5 and 7 days (p<0.05. CONCLUSION: No morphological change from the effect of induced tooth movement could be found in the dentin-pulp complex. In addition, no inflammatory or pulp degeneration, detectable in optical microscopy, was found in experimental groups.

Camila da Siveira Massaro

2009-01-01

182

Potential Role of Dentin Sialoprotein by Inducing Dental Pulp Mesenchymal Stem Cell Differentiation and Mineralization for Dental Tissue Repair  

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Full Text Available Introduction: Dentin sialoprotein (DSP is a dentin extracellular matrix protein, a unique marker of dentinogenesis and plays a vital role in odontoblast differentiation and dentin mineralization. Recently, studies have shown that DSP induces differentiation and mineralization of periodontal ligament stem cells and dental papilla mesenchymal cells in vitro and rescues dentin deficiency and increases enamel mineralization in animal models.The hypothesis: DSP as a nature therapeutic agent stimulates dental tissue repair by inducing endogenous dental pulp mesenchymal stem/progenitor cells into odontoblast-like cells to synthesize and to secrete dentin extracellular matrix forming new tertiary dentin as well as to regenerate a functional dentin-pulp complex. As DSP is a nature protein, and clinical procedure for DSP therapy is easy and simple, application of DSP may provide a new avenue for dentists with additional option for the treatment of substantially damaged vital teeth.Evaluation of the hypothesis: Dental caries is the most common dental disease. Deep caries and pulp exposure have been treated by various restorative materials with limited success. One promising approach is dental pulp stem/progenitor-based therapies to regenerate dentin-pulp complex and restore its functions by DSP induction in vivo.

Zhi Chen

2010-09-01

183

Expression of HMGB1 in the periodontal tissue subjected to orthodontic force application by Waldo's method in mice.  

Science.gov (United States)

Recent studies indicate that high mobility group box protein 1 (HMGB1) originating from periodontal ligament (PDL) cells can be a potential regulator in the process of orthodontic tooth movement and periodontal tissue remodeling. The aim of this study is to investigate HMGB1 expression in periodontal tissue during orthodontic tooth movement in mice according to Waldo's method. Six 7-week-old C57BL6 mice were used in these experiments. The elastic band was inserted into the teeth space between the right first and second maxillary molars. After 3 days of mechanical loading, mice were fixed with transcardial perfusion of 4 % paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and the maxillary was extracted for histochemical analyses. The histological examination revealed local PDL tear at the tension side and the formation of extensive cell-free hyaline zones at the compression side. The immunolocalization of HMGB1 was significantly presented at tension side of PDL, apical area and dental pulp, whereas at the compression side of PDL, the labeling of HMGB1 was almost undetectable as the presence of hyaline zone. Taken together, we concluded that the orthodontic tooth movement by Waldo's method leads to histological changes and HMGB1 expression pattern that differ from those of coil spring method, including PDL tear and extensive hyaline zone which may severely destroy periodontal tissue and in turn impede tooth movement. PMID:25523715

Lv, Shengyu; Li, Juan; Feng, Wei; Liu, Hongrui; Du, Juan; Sun, Jing; Cui, Jian; Sun, Bao; Han, Xiuchun; Oda, Kimimitsu; Amizuka, Norio; Xu, Xin; Li, Minqi

2015-02-01

184

Mechano-transduction in periodontal ligament cells identifies activated states of MAP-kinases p42/44 and p38-stress kinase as a mechanism for MMP-13 expression  

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Full Text Available Abstract Background Mechano-transduction in periodontal ligament (PDL cells is crucial for physiological and orthodontic tooth movement-associated periodontal remodelling. On the mechanistic level, molecules involved in this mechano-transduction process in PDL cells are not yet completely elucidated. Results In the present study we show by western blot (WB analysis and/or indirect immunofluorescence (IIF that mechanical strain modulates the amount of the matrix metalloproteinase MMP-13, and induces non-coherent modulation in the amount and activity of signal transducing molecules, such as FAK, MAP-kinases p42/44, and p38 stress kinase, suggesting their mechanistic role in mechano-transduction. Increase in the amount of FAK occurs concomitant with increased levels of the focal contact integrin subunits ?3 and ?1, as indicated by WB or optionally by IIF. By employing specific inhibitors, we further identified p42/44 and p38 in their activated, i.e. phosphorylated state responsible for the expression of MMP-13. This finding may point to the obedience in the expression of this MMP as extracellular matrix (ECM remodelling executioner from the activation state of mechano-transducing molecules. mRNA analysis by pathway-specific RT-profiler arrays revealed up- and/or down-regulation of genes assigning to MAP-kinase signalling and cell cycle, ECM and integrins and growth factors. Up-regulated genes include for example focal contact integrin subunit ?3, MMP-12, MAP-kinases and associated kinases, and the transcription factor c-fos, the latter as constituent of the AP1-complex addressing the MMP-13 promotor. Among others, genes down-regulated are those of COL-1 and COL-14, suggesting that strain-dependent mechano-transduction may transiently perturbate ECM homeostasis. Conclusions Strain-dependent mechano-/signal-transduction in PDL cells involves abundance and activity of FAK, MAP-kinases p42/44, and p38 stress kinase in conjunction with the amount of MMP-13, and integrin subunits ?1 and ?3. Identifying the activated state of p42/44 and p38 as critical for MMP-13 expression may indicate the mechanistic contribution of mechano-transducing molecules on executioners of ECM homeostasis.

Kohl Annette

2010-01-01

185

TGF-?-operated growth inhibition and translineage commitment into smooth muscle cells of periodontal ligament-derived endothelial progenitor cells through Smad- and p38 MAPK-dependent signals.  

Science.gov (United States)

The periodontal ligament (PDL) is a fibrous connective tissue that attaches the tooth to the alveolar bone. We previously demonstrated the ability of PDL fibroblast-like cells to construct an endothelial cell (EC) marker-positive blood vessel-like structure, indicating the potential of fibroblastic lineage cells in PDL tissue as precursors of endothelial progenitor cells (EPCs) to facilitate the construction of a vascular system around damaged PDL tissue. A vascular regeneration around PDL tissue needs proliferation of vascular progenitor cells and the subsequent differentiation of the cells. Transforming growth factor-? (TGF-?) is known as an inducer of endothelial-mesenchymal transition (EndMT), however, it remains to be clarified what kinds of TGF-? signals affect growth and mesenchymal differentiation of PDL-derived EPC-like fibroblastic cells. Here, we demonstrated that TGF-?1 not only suppressed the proliferation of the PDL-derived EPC-like fibroblastic cells, but also induced smooth muscle cell (SMC) markers expression in the cells. On the other hand, TGF-?1 stimulation suppressed EC marker expression. Intriguingly, overexpression of Smad7, an inhibitor for TGF-?-induced Smad-dependent signaling, suppressed the TGF-?1-induced growth inhibition and SMC markers expression, but did not the TGF-?1-induced downregulation of EC marker expression. In contrast, p38 mitogen-activated protein kinase (MAPK) inhibitor SB 203580 suppressed the TGF-?1-induced downregulation of EC marker expression. In addition, the TGF-?1-induced SMC markers expression of the PDL-derived cells was reversed upon stimulation with fibroblast growth factor (FGF), suggesting that the TGF-?1 might not induce terminal SMC differentiation of the EPC-like fibroblastic cells. Thus, TGF-?1 not only negatively controls the growth of PDL-derived EPC-like fibroblastic cells via a Smad-dependent manner but also positively controls the SMC-differentiation of the cells possibly at the early stage of the translineage commitment via Smad- and p38 MAPK-dependent manners. PMID:22949889

Yoshida, Mariko; Okubo, Naoto; Chosa, Naoyuki; Hasegawa, Tomokazu; Ibi, Miho; Kamo, Masaharu; Kyakumoto, Seiko; Ishisaki, Akira

2012-01-01

186

Spatiotemporally controlled microchannels of periodontal mimic scaffolds.  

Science.gov (United States)

Physiologic bioengineering of the oral, dental, and craniofacial complex requires optimized geometric organizations of fibrous connective tissues. A computer-designed, fiber-guiding scaffold has been developed to promote tooth-supporting periodontal tissue regeneration and functional restoration despite limited printing resolution for the manufacture of submicron-scaled features. Here, we demonstrate the use of directional freeze-casting techniques to control pore directional angulations and create mimicked topographies to alveolar crest, horizontal, oblique, and apical fibers of natural periodontal ligaments. For the differing anatomic positions, the gelatin displayed varying patterns of ice growth, determined via internal pore architectures. Regardless of the freezing coordinates, the longitudinal pore arrangements resulted in submicron-scaled diameters (~50 µm), along with corresponding high biomaterial porosity (~90%). Furthermore, the horizontal + coronal ([Formula: see text]) freezing orientation facilitated the creation of similar structures to major fibers in the periodontal ligament interface. This periodontal tissue-mimicking microenvironment is a potential tissue platform for the generation of naturally oriented ligamentous tissues consistent with periodontal ligament neogenesis. PMID:25216511

Park, C H; Kim, K H; Rios, H F; Lee, Y M; Giannobile, W V; Seol, Y J

2014-12-01

187

Enamel matrix protein derivatives: role in periodontal regeneration  

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Full Text Available Vandana J RathvaDepartment of Periodontics, KM Shah Dental College and Hospital, Sumandeep University, Gujarat, IndiaAbstract: The role of regenerative periodontal therapy is the reconstitution of lost periodontal structures, ie, new formation of root cementum, periodontal ligament, and alveolar bone. The outcome of basic research has pointed to the important role of enamel matrix protein derivative (EMD in periodontal wound healing. Histologic results from animal and human studies have shown that treatment with EMD promotes periodontal regeneration. Moreover, clinical studies have indicated that treatment with EMD positively influences periodontal wound healing in humans. The goal of this paper is to review the existing literature on EMD.Keywords: enamel matrix protein derivative, Emdogain®, periodontal regeneration

Rathva VJ

2011-12-01

188

A review on periodontitis versus endodontics  

OpenAIRE

Periodontitis (pair-e-o-don-TI-tis) may be a serious gum infection that destroys the soft tissue and bone that support your teeth and endodontics is focused on the detection and treatment of pulp diseases as well. Disease will cause tooth loss or worse, associate with nursing inflated risk of heart failure or stroke and different serious health issues. Endodontics or periodontitis is however common for the most parts preventable. Disease is so...

Mohammad Salarpour; Mahsa Bamadi; Elaheh Salarpour; Masood Bamadi

2013-01-01

189

Comparative evaluation of lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) levels in periodontal diseases  

OpenAIRE

Introduction: Periodontitis is a chronic multi-factorial infectious disease characterized by irreversible destruction of collagen fibers and other matrix constituents of the gingival tissues and periodontal ligament, and resorption of alveolar bone around the teeth with periodontal pocket formation. Host response to periodontal disease includes production of different enzymes that are released by stromal, epithelial or inflammatory cells associated with cell injury and cell death, i...

Arash Azizi; Ardeshir Ranjbari; Mohammad Ali Ghafari; Fatemeh Jahan

2011-01-01

190

Comparison of the Amount of IL-1ß in Periodontally Involved Patients’ Saliva and Healthy Subjects  

OpenAIRE

Statement of Problem: Periodontitis is a chronic multi-factorial infectious disease,characterized by irreversible destruction of collagen fibers and other matrix constituents of the gingival tissues, periodontal ligament and resorption of the alveolar bone around the teeth with formation of periodontal pocket. Cytokines such as IL-1? are one of the components of host’s immune system and seem to play an important role in periodontitisPurpose: The aim of this study...

Azizi A.; Ranjbari A.; Sm, Ghafari; Sm, Alavi

2012-01-01

191

TGF-?-Operated Growth Inhibition and Translineage Commitment into Smooth Muscle Cells of Periodontal Ligament-Derived Endothelial Progenitor Cells through Smad- and p38 MAPK-Dependent Signals  

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Full Text Available The periodontal ligament (PDL is a fibrous connective tissue that attaches the tooth to the alveolar bone. We previously demonstrated the ability of PDL fibroblast-like cells to construct an endothelial cell (EC marker-positive blood vessel-like structure, indicating the potential of fibroblastic lineage cells in PDL tissue as precursors of endothelial progenitor cells (EPCs to facilitate the construction of a vascular system around damaged PDL tissue. A vascular regeneration around PDL tissue needs proliferation of vascular progenitor cells and the subsequent differentiation of the cells. Transforming growth factor-? (TGF-? is known as an inducer of endothelial-mesenchymal transition (EndMT, however, it remains to be clarified what kinds of TGF-? signals affect growth and mesenchymal differentiation of PDL-derived EPC-like fibroblastic cells. Here, we demonstrated that TGF-?1 not only suppressed the proliferation of the PDL-derived EPC-like fibroblastic cells, but also induced smooth muscle cell (SMC markers expression in the cells. On the other hand, TGF-?1 stimulation suppressed EC marker expression. Intriguingly, overexpression of Smad7, an inhibitor for TGF-?-induced Smad-dependent signaling, suppressed the TGF-?1-induced growth inhibition and SMC markers expression, but did not the TGF-?1-induced downregulation of EC marker expression. In contrast, p38 mitogen-activated protein kinase (MAPK inhibitor SB 203580 suppressed the TGF-?1-induced downregulation of EC marker expression. In addition, the TGF-?1-induced SMC markers expression of the PDL-derived cells was reversed upon stimulation with fibroblast growth factor (FGF, suggesting that the TGF-?1 might not induce terminal SMC differentiation of the EPC-like fibroblastic cells. Thus, TGF-?1 not only negatively controls the growth of PDL-derived EPC-like fibroblastic cells via a Smad-dependent manner but also positively controls the SMC-differentiation of the cells possibly at the early stage of the translineage commitment via Smad- and p38 MAPK-dependent manners.

Mariko Yoshida, Naoto Okubo, Naoyuki Chosa, Tomokazu Hasegawa, Miho Ibi, Masaharu Kamo, Seiko Kyakumoto, Akira Ishisaki

2012-01-01

192

Periodontal (Gum) Disease  

Science.gov (United States)

... Statistics > Find Data by Topic > Periodontal (Gum) Disease Periodontal (Gum) Disease Main Content Periodontal disease is the most common cause of tooth ... Overall, the prevalence of both moderate and severe periodontal disease in adults and Seniors has decreased from ...

193

Clinical evaluation of endodotic therapy on periodontal tissue healing in chronic advanced periodontitis  

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Full Text Available Statement of Problem: There is a controversy about the relationship between pulpal and periodontal diseases. The interrelationship between pulp and periodontium could have an important effect on the treatment plan of the tooth. Purpose: The aim of the present research is to evaluate root canal therapy effects on periodontal healing of teeth with chronic advanced periodontitis. Materials and Methods: In this randomized controlled clinical trial 32 single rooted teeth which had necrotic pulp or irreversible pulpitis in 7 patients with chronic advanced periodontitis were selected based on specific criteria. Using a split mouth design, teeth were randomly put in two groups of test and control. In the test group root canal therapy ,scaling & root planing were done.In the control group, only scaling & root planing were performed. Clinical parameters including Pocket Depth (PD, Clinical Attachment Level (CAL, mobility, pattern of bone destruction and plaque index (PI were evaluated in two groups at base line, 1 and 3 months after treatment. Appropriate tests such as paired Wilcoxon and Mann-Whitney were performed. Results: Statistically significant reductions were found in the test group when comparing baseline and one-month post treatment values for Clinical Attachment level (CAL but not after 3-months. In the control group the CAL reductions were not statistically significant between baseline and one month post-treatment, but a increase were observed between one month and three months after treatment. There was a statstically significant difference between the test and the control groups. Other parameters didn’t show any significant differences in each group and between two groups. Conclusion: Since clinical attachment level was the most important parameter we found it can high lighted the role of pathogene with pulpal origin in progression of periodeontal disease and it is concluded that beside periodontal treatment in some advanced periodontal cases pulp therapy maybe an effective procedure for eleminating destructive pathogens of pulp and causing periodontal healing.

Sadeghi R.

2004-08-01

194

Regeneração periodontal em cães Periodontal regeneration in dogs  

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Full Text Available A doença periodontal pode ser definida como a condição inflamatória dos tecidos de suporte do dente em resposta ao acúmulo do biofilme. A consequencia é a formação de graves defeitos ósseos, devido à perda dos tecidos periodontais, levando, em última instância, à perda dos dentes, predisposição a fraturas de mandíbula e formação de comunicações oronasais. O principal tratamento é a prevenção, incluindo a escovação dentária diária e a profilaxia periodontal, procedimento realizado pelo médico veterinário para remoção do biofilme e cálculo dentário acumulados. A recuperação dos tecidos perdidos, ou seja, a regeneração periodontal, é um processo mais complexo, pois envolve a formação de três tecidos intimamente ligados: osso alveolar, ligamento periodontal e cemento. Assim, diversos materiais e técnicas foram e são constantemente desenvolvidos, incluindo membranas para regeneração tecidual guiada e a aplicação de enxertos e biomateriais, amplamente estudados na odontologia humana e já disponíveis para aplicação na rotina clínica veterinária. Adicionalmente, novas possibilidades surgem com a associação dessas técnicas a fatores de crescimento e células-tronco e o desenvolvimento das membranas multifuncionais.Periodontal disease can be defined as the inflammatory condition of the tooth-supportive tissues as a response to biofilm accumulation. The consequence is the formation of severe bone defects due to the loss of periodontal tissues that ultimately lead to tooth loss, predispose to mandible fractures and formation of oronasal communications. The main treatment is prevention, including daily tooth brushing and periodontal prophylaxis, a procedure done by veterinaries to remove retained biofilm and calculus. Recovering lost tissues, i.e. periodontal regeneration, is a more complex process involving the formation of three tissues highly connected: alveolar bone, periodontal ligament and cementum. Therefore, several materials and techniques were and are constantly developed, including membranes for guided tissue regeneration and the application of bone grafts and biomaterials, widely studied in human dentistry and already available for veterinary practice. Additionally, new possibilities rise with the association of these techniques to growth factors and stem cells and the development of multifunctional membranes.

Emily Correna Carlo Reis

2011-12-01

195

Regeneração periodontal em cães / Periodontal regeneration in dogs  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A doença periodontal pode ser definida como a condição inflamatória dos tecidos de suporte do dente em resposta ao acúmulo do biofilme. A consequencia é a formação de graves defeitos ósseos, devido à perda dos tecidos periodontais, levando, em última instância, à perda dos dentes, predisposição a fr [...] aturas de mandíbula e formação de comunicações oronasais. O principal tratamento é a prevenção, incluindo a escovação dentária diária e a profilaxia periodontal, procedimento realizado pelo médico veterinário para remoção do biofilme e cálculo dentário acumulados. A recuperação dos tecidos perdidos, ou seja, a regeneração periodontal, é um processo mais complexo, pois envolve a formação de três tecidos intimamente ligados: osso alveolar, ligamento periodontal e cemento. Assim, diversos materiais e técnicas foram e são constantemente desenvolvidos, incluindo membranas para regeneração tecidual guiada e a aplicação de enxertos e biomateriais, amplamente estudados na odontologia humana e já disponíveis para aplicação na rotina clínica veterinária. Adicionalmente, novas possibilidades surgem com a associação dessas técnicas a fatores de crescimento e células-tronco e o desenvolvimento das membranas multifuncionais. Abstract in english Periodontal disease can be defined as the inflammatory condition of the tooth-supportive tissues as a response to biofilm accumulation. The consequence is the formation of severe bone defects due to the loss of periodontal tissues that ultimately lead to tooth loss, predispose to mandible fractures [...] and formation of oronasal communications. The main treatment is prevention, including daily tooth brushing and periodontal prophylaxis, a procedure done by veterinaries to remove retained biofilm and calculus. Recovering lost tissues, i.e. periodontal regeneration, is a more complex process involving the formation of three tissues highly connected: alveolar bone, periodontal ligament and cementum. Therefore, several materials and techniques were and are constantly developed, including membranes for guided tissue regeneration and the application of bone grafts and biomaterials, widely studied in human dentistry and already available for veterinary practice. Additionally, new possibilities rise with the association of these techniques to growth factors and stem cells and the development of multifunctional membranes.

Emily Correna Carlo, Reis; Andréa Pacheco Batista, Borges; Ricardo Junqueira, Del Carlo.

2128-21-01

196

A review on periodontitis versus endodontics  

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Full Text Available Periodontitis (pair-e-o-don-TI-tis may be a serious gum infection that destroys the soft tissue and bone that support your teeth and endodontics is focused on the detection and treatment of pulp diseases as well. Disease will cause tooth loss or worse, associate with nursing inflated risk of heart failure or stroke and different serious health issues. Endodontics or periodontitis is however common for the most parts preventable. Disease is sometimes the result of poor oral hygiene. Daily brushing and flossing and regular skilled dental cleanings will greatly cut back your probability of developing disease. The purpose of the current review is to explore the important role for periodontitis/endodontics prevention in oral hygiene and health as well. In this review periodontitis/endodontics will be discussed in details in all aspects.

Mohammad Salarpour

2013-11-01

197

Analysis of the dentin-pulp complex in teeth submitted to orthodontic movement in rats  

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Full Text Available SciELO Brazil | Language: English Abstract in english In order to microscopically analyze the pulpal effects of orthodontic movement, 49 maxillary first molars of rats were submitted to orthodontic appliance composed of a closed coil spring anchored to the maxillary incisors, placed for the achievement of mesial movement. MATERIAL AND METHODS: Ten anim [...] als were used as the control group and were not submitted to orthodontic force; the other animals were divided into groups according to the study period of tooth movement, namely 1, 2, 3, 4, 5, 6 and 7 days. The investigation of pulp and periodontal changes included hyalinization, fibrosis, reactive dentin and vascular congestion. Statistical evaluation was performed between control and experimental groups and between periods of observation using non-parametric chi-square, Kruskal-Wallis and Dunn tests. RESULTS: There was no statistically significant difference concerning pulpal changes between control and experimental groups nor between periods of observation. The control group, at 3 and 5 days, revealed greater hyalinization of the periodontal ligament (p

Camila da Siveira, Massaro; Renata Bianco, Consolaro; Milton, Santamaria Junior; Maria Fernanda Martins-Ortiz, Consolaro; Alberto, Consolaro.

198

Periodontal biomechanics: finite element simulations of closing stroke and power stroke in equine cheek teeth  

OpenAIRE

Abstract Background In equine dentistry periodontal diseases, especially periapical inflammation, are frequently occurring problems. Anachoresis is believed to be the most common cause for the development of such disorders. Nevertheless, there is still no substantiated explanation why settlement of pathogen microorganisms occurs in equine periodontal tissues. It is expected that excessive strains and stresses occurring in the periodontal ligament (PDL) during the horse’s ch...

Cordes Vanessa; Lüpke Matthias; Gardemin Moritz; Seifert Hermann; Staszyk Carsten

2012-01-01

199

Elevated extracellular calcium increases expression of bone morphogenetic protein-2 gene via a calcium channel and ERK pathway in human dental pulp cells  

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Dental pulp cells, which have been shown to share phenotypical features with osteoblasts, are capable of differentiating into odontoblast-like cells and generating a dentin-like mineral structure. Elevated extracellular Ca{sup 2+}Ca{sub o}{sup 2+} has been implicated in osteogenesis by stimulating the proliferation and differentiation of osteoblasts; however, the role of Ca{sub o}{sup 2+} signaling in odontogenesis remains unclear. We found that elevated Ca{sub o}{sup 2+} increases bone morphogenetic protein (BMP)-2 gene expression in human dental pulp cells. The increase was modulated not only at a transcriptional level but also at a post-transcriptional level, because treatment with Ca{sup 2+} increased the stability of BMP-2 mRNA in the presence of actinomycin D, an inhibitor of transcription. A similar increase in BMP-2 mRNA level was observed in other human mesenchymal cells from oral tissue; periodontal ligament cells and gingival fibroblasts. However, the latter cells exhibited considerably lower expression of BMP-2 mRNA compared with dental pulp cells and periodontal ligament cells. The BMP-2 increase was markedly inhibited by pretreatment with an extracellular signal-regulated kinase (ERK) inhibitor, PD98059, and partially inhibited by the L-type Ca{sup 2+} channels inhibitor, nifedipine. However, pretreatment with nifedipine had no effect on ERK1/2 phosphorylation triggered by Ca{sup 2+}, suggesting that the Ca{sup 2+} influx from Ca{sup 2+} channels may operate independently of ERK signaling. Dental pulp cells do not express the transcript of Ca{sup 2+}-sensing receptors (CaSR) and only respond slightly to other cations such as Sr{sup 2+} and spermine, suggesting that dental pulp cells respond to Ca{sub o}{sup 2+} to increase BMP-2 mRNA expression in a manner different from CaSR and rather specific for Ca{sub o}{sup 2+} among cations.

Tada, Hiroyuki [Division of Periodontology and Endodontology, Tohoku University Graduate School of Dentistry, Sendai 980-8575 (Japan); Nemoto, Eiji, E-mail: e-nemoto@umin.ac.jp [Division of Periodontology and Endodontology, Tohoku University Graduate School of Dentistry, Sendai 980-8575 (Japan); Kanaya, Sousuke; Hamaji, Nozomu; Sato, Hisae; Shimauchi, Hidetoshi [Division of Periodontology and Endodontology, Tohoku University Graduate School of Dentistry, Sendai 980-8575 (Japan)

2010-04-16

200

Dental Investigations: Efficiency of Nonsurgical Periodontal Therapy in Moderate Chronic Periodontitis  

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Full Text Available INTRODUCTION: Chronic periodontitis is defined as an inflammatory disease of the supporting tissues of teeth caused by microorganisms in the dental biofilm, resulting in progressive destruction of the periodontal ligament and alveolar bone with pocket formation and gingival recession. Treatment of chronic periodontitis aims at arresting the inflammation and stopping the loss of attachment by removal and control of the supra- and subgingival biofilm and establishing a local environment and microflora compatible with periodontal health. The AIM of this study was to evaluate the effectiveness of non-surgical therapy (scaling and root planning in the treatment of moderate chronic periodontitis. MATERIALS AND METHODS: The study included 30 patients aged between 33 and 75 years, of which 46.7% women and 53.3% men, diagnosed with moderate and, at some sites, severe periodontitis. They were treated with non-surgical periodontal therapy methods (scaling and root planning and curettage if indicated. Additionally, chemical plaque control with rinse water containing chlorhexidine was applied. The diagnostic and reassessment procedures included measuring the periodontal indices of 601 periodontal units before and after the therapy. The indices measured were the papillary bleeding index (PBI, the hygiene index (HI, the probing pocket depth (PPD and the clinical attachment level (CAL. RESULTS: Significant reduction of plaque and gingival inflammation was found in all treated patients; we also found a statistically significant reduction of periodontal pockets with clinically measured depth ? 5 mm (PD ? 5 mm. Pockets with PD > 5 mm did not show statistically significant lower incidence rates probably due to the initially small percentage of deep pockets in the patients studied. There was a statistically significant reduction of all sites with attachment loss, the highest significance found at sites where the attachment loss was greater than 5 mm. CONCLUSION: The results of the study suggest that nonsurgical periodontal therapy is effective in managing the moderate chronic periodontitis. Given a good patient compliance, the antimicrobial periodontal therapy can be quite efficient in arresting the inflammatory process and reducing the depth of periodontal pockets; it can also achieve a stable attachment loss level and obviate the need to use a surgical periodontal treatment modality.

Mlachkova Antoaneta M.

2014-08-01

201

Multiphasic scaffolds for periodontal tissue engineering.  

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For a successful clinical outcome, periodontal regeneration requires the coordinated response of multiple soft and hard tissues (periodontal ligament, gingiva, cementum, and bone) during the wound-healing process. Tissue-engineered constructs for regeneration of the periodontium must be of a complex 3-dimensional shape and adequate size and demonstrate biomechanical stability over time. A critical requirement is the ability to promote the formation of functional periodontal attachment between regenerated alveolar bone, and newly formed cementum on the root surface. This review outlines the current advances in multiphasic scaffold fabrication and how these scaffolds can be combined with cell- and growth factor-based approaches to form tissue-engineered constructs capable of recapitulating the complex temporal and spatial wound-healing events that will lead to predictable periodontal regeneration. This can be achieved through a variety of approaches, with promising strategies characterized by the use of scaffolds that can deliver and stabilize cells capable of cementogenesis onto the root surface, provide biomechanical cues that encourage perpendicular alignment of periodontal fibers to the root surface, and provide osteogenic cues and appropriate space to facilitate bone regeneration. Progress on the development of multiphasic constructs for periodontal tissue engineering is in the early stages of development, and these constructs need to be tested in large animal models and, ultimately, human clinical trials. PMID:25139362

Ivanovski, S; Vaquette, C; Gronthos, S; Hutmacher, D W; Bartold, P M

2014-12-01

202

Periodontal Probe Improves Exams, Alleviates Pain  

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Dentists, comedian Bill Cosby memorably mused, tell you not to pick your teeth with any sharp metal object. Then you sit in their chair, and the first thing they grab is an iron hook!" Conventional periodontal probing is indeed invasive, uncomfortable for the patient, and the results can vary greatly between dentists and even for repeated measurements by the same dentist. It is a necessary procedure, though, as periodontal disease is the most common dental disease, involving the loss of teeth by the gradual destruction of ligaments that hold teeth in their sockets in the jawbone. The disease usually results from an increased concentration of bacteria in the pocket, or sulcus, between the gums and teeth. These bacteria produce acids and other byproducts, which enlarge the sulcus by eroding the gums and the periodontal ligaments. The sulcus normally has a depth of 1 to 2 millimeters, but in patients with early stages of periodontal disease, it has a depth of 3 to 5 millimeters. By measuring the depth of the sulcus, periodontists can have a good assessment of the disease s progress. Presently, there are no reliable clinical indicators of periodontal disease activity, and the best available diagnostic aid, periodontal probing, can only measure what has already been lost. A method for detecting small increments of periodontal ligament breakdown would permit earlier diagnosis and intervention with less costly and time-consuming therapy, while overcoming the problems associated with conventional probing. The painful, conventional method for probing may be destined for the archives of dental history, thanks to the development of ultrasound probing technologies. The roots of ultrasound probes are in an ultrasound-based time-of-flight technique routinely used to measure material thickness and length in the Nondestructive Evaluation Sciences Laboratory at Langley Research Center. The primary applications of that technology have been for corrosion detection and bolt tension measurements (Spinoff 2005). This ultrasound measurement system was adapted to the Periodontal Structures Mapping System, invented at Langley by John A. Companion, under the supervision of Dr. Joseph S. Heyman. Support of the research and development that led to this invention was provided by NASA s Technology Applications Engineering Program and by the Naval Institute for Dental and Biomedical Research, in Great Lakes, Illinois.

2008-01-01

203

Periodontal Plastic Surgery Procedures  

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... Procedures Periodontal Plastic Surgery Procedures Find a Periodontist Periodontal Plastic Surgery Procedures Periodontists are often considered the ... a result of a variety of causes, including periodontal diseases. Gum graft surgery and other root coverage ...

204

Periodontal Treatments and Procedures  

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... Procedures Periodontal Plastic Surgery Procedures Find a Periodontist Periodontal Treatments and Procedures Periodontists are dentistry's e?xperts in treating periodontal disease. They receive up to three additional years ...

205

Formation of the periodontal attachment in developing rabbit permanent incisors.  

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Permanent incisors from fetal New Zealand white rabbits aged 25-30 days in utero and from 1-20 days postnatally were processed for light microscopy. Examination of longitudinal and cross-sections revealed that cementum deposition and fiber attachment first occurred at 27 days in utero. A tooth-to-bone course of principal fibers confined to lateral aspects of the teeth was observed in 29-day fetal incisors, whereas lingually the periodontal ligament remained undeveloped as late as 5 days postnatally. In 20-day postnatal incisors, the development of the functional periodontal ligament was complete as evidenced by the fiber arrangement on all aspects of the root-analogue tooth surface. This study shows that 25-26-day fetal rabbit permanent incisors represent the end of the follicular phase, whereas 27-day fetal to 20-day postnatal teeth demonstrate distinct histologic characteristics of initial, incomplete and complete periodontal fiber attachment. PMID:6576463

Grevstad, H J; Selvig, K A

1983-06-01

206

Periodontal Disease Part IV: Periodontal Infections  

OpenAIRE

In Part IV of this article, the author describes two periodontal infections, acute necrotizing ulcerative gingivitis (trench mouth) and periodontal abscess, both acute painful conditions for which patients may seek advice from their family physician rather than their dentist.

Turnbull, Robert S.

1988-01-01

207

Considerations for physicians caring for older adults with periodontal disease.  

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Periodontal disease is a generic term encompassing a variety of inflammatory conditions affecting the supporting tissues of the teeth. Periodontitis is inflammation associated with net resorption of supporting alveolar bone and periodontal ligament. Gingivitis is inflammation limited to the covering gingival tissues and does not directly lead to tooth mobility or loss. Periodontal diseases are very prevalent. Because the bone and ligament resorption are essentially irreversible, accumulated tissue damage of periodontitis is reflected in a prevalence and severity that increase with age. Periodontitis is not caused by aging per se but by a complex host-parasite relationship in which specific pathogens among the subgingival microbiota not only injure tissues directly but stimulate a cascade of inflammatory mediators to damage host tissues. Analytic epidemiology has identified several risk indicators for advanced periodontitis in older adults. These are microbiologic (prevalence of certain anaerobes in the microbiota), behavioral (tobacco smoking and infrequent professional dental care), medical (older age, preexisting and generalized periodontitis, gingival bleeding), and social (financial worries). Periodontitis in older adults is treated by reducing the impact of these risk indicators. The infections are controlled by combinations of debridement, antimicrobial agents, and surgical procedures as indicated. Medically well older adults can be treated similarly to younger adults. Management of periodontal conditions can be complicated for patients who are medically compromised. Communication between physicians and dental personnel is often required to ascertain the medical history and list of medications taken by older patients. Many of the medications prescribed for medical problems associated with aging impact on treatment choices for managing periodontitis. Moreover, periodontists frequently prescribe analgesics, antibiotics, and anti-inflammatory agents that might interact with others among the numerous drugs taken by older patients. Older adults with cognitive or physical disabilities have special needs for individualized hygiene instruction and implements. Periodontal health promotion and improving access to periodontal care for the elderly are challenges, because dental services are most often in the private sector and dental insurance does not often apply after retirement. Because they grew up in an era in which tooth loss due to "gum" diseases was considered inevitable, their current motivation toward regular preventive care must be improved by removing barriers and impediments to care. In addition to life-threatening medical conditions, frail individuals institutionalized in collective living centers face compounded problems concerning the provision of adequate, not even optimal, dental care. Their periodontal health often deteriorates rapidly after institutionalization, and in some instances it can possibly predispose to aspiration pneumonia or other disseminated infections.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1504948

Ellen, R P

1992-08-01

208

Periodontal Disease and Systemic Health  

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... Procedures Periodontal Plastic Surgery Procedures Find a Periodontist Periodontal Disease and Systemic Health Research has shown that periodontal disease is associated with several other diseases. For ...

209

Timing of pulp extirpation for replanted avulsed teeth.  

LENUS (Irish Health Repository)

A search was performed (April 2004) across four databases, namely Ovid Medline, Cochrane Library, PubMed and Web of Science, relevant to the proposed PICO ( Patient or problem, Intervention, Comparison, Outcome) question: (P) for a replanted avulsed permanent tooth, (I) is early pulp extirpation within 10-14 days of replantation, (C) compared with delayed pulp extirpation, (O) associated an increased likelihood of successful periodontal healing after tooth replantation. Only articles published in the English language were considered.

Stewart, Chris

2009-01-01

210

Posterior cruciate ligament (PCL) injury  

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Cruciate ligament injury - posterior; PCL injury; Knee injury - posterior cruciate ligament (PCL); Hyperextended knee ... The posterior cruciate ligament (PCL) is the strongest ligament in the knee. It extends from the top-rear surface of the ...

211

Stem cells: A new paradigm in periodontal regeneration  

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Full Text Available Stem cells are a unique type of cell that forms the basis of the development, growth and survival of a living organism. Though the term is often used to describe controversial embryonic stem cells, there are many different types of stem cells, classified by their original location and/or method of formation. Stem cells are undifferentiated cells that go on developing into any of more than 200 type of cells that adult Human body hold. Now a days stem cells have significant use in regenerative periodontal therapy. Recently, reports have begun to emerge demonstrating that populations of adult stem cells reside in the periodontal ligament of humans and other animals. This opens the way for new cell-based therapies for periodontal regeneration.This review provides an overview of adult human stem cells and their potential use in periodontal regeneration.

Marawar Pramod P, Shinde Sagar K, Mani Ameet M, Patil Ishwardas D

2013-04-01

212

Root grooves: a risk factor in periodontal attachment loss.  

Science.gov (United States)

Periodontal health reflects a balance between harmful and protective elements in the gingival margin area. The total plaque mass, specific periodontopathogens, and local environmental factors may challenge this balance. The aim of this retrospective study was to evaluate the effect of proximal root grooves as a risk factor in periodontal attachment loss. One-hundred and three (103) extracted, formalin-stored, single-rooted teeth showing loss of attachment and having one non-grooved and one grooved proximal root surface were selected for the study. Following staining in 0.1% toluidine blue to visualize attached periodontal ligament remnants, the teeth were examined in a light microscope under incident light. On each tooth, loss of attachment was measured along the long axis of the root from the cemento-enamel junction to the most coronal level of the stained periodontal ligament remnants on mesial as well as on distal surfaces. Incisors and premolars were grouped separately. For both groups, a statistically significant greater loss of attachment was present on grooved than on non-grooved surfaces (P < 0.0001). Generally, there was a direct relationship between groove location and maximum loss of attachment. The results indicate that proximal root grooves should be considered in periodontal diagnosis, prognosis, and treatment planning. PMID:7990023

Leknes, K N; Lie, T; Selvig, K A

1994-09-01

213

Influence of periodontitis and nonsurgical periodontal intervention on atherosclerosis diseases  

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Full Text Available Objective: Periodontitis and atherosclerosis diseases are chronic inflammatory disorders which are highly prevalent in populations. Nonsurgical periodontal intervention belongs to the initial therapy strategy to periodontal diseases. Periodontal pathogen can enter into blood stream through the ulceration epithelial resulting in bacteraemia when periodontitis is severe. The objective is to investigate the relationship between periodontitis and atherosclerosis diseases, and the influence of nonsurgical periodontal intervention on atheroma and atherosclerosis diseases. Methods: This study reviewed and analyzed the papers which published in the world associated with periodontitis or periodontal intervention on atherosclerosis diseases. Results: Periodontitis and periodontal infectious are important risk factors for atherosclerotic diseases. Much evidence has proved the durative severe periodontitis can result in bacteraemia and systemic inflammation, elevated C-response protein in serum, gingival microcirculation changed, periodontal microorganism reproduced, and endothelial dys-function and endocarditis. Nonsurgical periodontal intervention can remove the pathogenesis bacteria and calculus to recover periodontal health. Effective periodontal therapy can reduce bacteraemia and stop the hurt to vessels. Nonsurgical periodontal therapy may interfere periodontal bacteria, inhibit inflammation response and C-response protein, improving gingival microcirculation and vessel epithelial function to prevent atherosclerosis. Conclusion: Nonsurgical periodontal intervention can improve or decrease the rate of atherosclerotic disease by interfere the severe periodontitis. The detailed mechanism of periodontal intervention on atheroma and atherosclerotic disease is still need to be explored.

Tielou Chen

2012-08-01

214

Fighting for territories: time-lapse analysis of dental pulp and dental follicle stem cells in co-culture reveals specific migratory capabilities  

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Full Text Available Stem cell migration is a critical step during the repair of damaged tissues. In order to achieve appropriate cell-based therapies for tooth and periodontal ligament repair it is necessary first to understand the dynamics of tissue-specific stem cell populations such as dental pulp stem cells (DPSC and dental follicle stem cells (DFSC. Using time-lapse imaging, we analysed migratory and proliferative capabilities of these two human stem cell lines in vitro. When cultured alone, both DPSC and DFSC exhibited low and irregular migration profiles. In co-cultures, DFSC, but not DPSC, spectacularly increased their migration activity and velocity. DFSC rapidly surrounded the DPSC, thus resembling the in vivo developmental process, where follicle cells encircle both dental epithelium and pulp. Cell morphology was dependent on the culture conditions (mono-culture or co-culture and changed over time. Regulatory genes involved in dental cell migration and differentiation such as TWIST1, MSX1, RUNX2, SFRP1 and ADAM28, were also evaluated in co-cultures. MSX1 up-regulation indicates that DPSC and DFSC retain their odontogenic potential. However, DPSC lose their capacity to differentiate into odontoblasts in the presence of DFSC, as suggested by RUNX2 up-regulation and TWIST1 down-regulation. In contrast, the unchanged levels of SFRP1 expression suggest that DFSC retain their potential to form periodontal tissues even in the presence of DPSC. These findings demonstrate that stem cells behave differently according to their environment, retain their genetic memory, and compete with each other to acquire the appropriate territory. Understanding the mechanisms involved in stem cell migration may lead to new therapeutic approaches for tooth repair.

C Schiraldi

2012-11-01

215

Qat Habit in Yemen Society: A Causative Factor for Oral Periodontal Diseases  

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Full Text Available The effect of a common habit among Yemeni population on the periodontal status was investigated. This cross-sectional study was done on 2500 Yemenis with mean age 27.01 years (1818 males and 682 females. Among these 1528 were qat chewers and 972 were non-chewers. Detailed questionnaire and pre-designed scoring system for the periodontal status were employed for each case. Study results indicated that out of 972 non-chewers 116(12% had periodontal pocketing and 18 (1.9% cases had gingival recession. On the other hand, out of 1528 chewers, 468 (31.8% had periodontal pockets and 98 (6.4% with gum bleeding, p<0.05. These effects were found to increase with increased frequency and duration of chewing. It was concluded that habit of qat can cause damage to the periodontal ligament as pocketing and gum recession.

Aiman A. Ali

2007-09-01

216

The Relationship between Rheumatoid Arthritis and Periodontitis  

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Full Text Available Introduction: Periodontitis is an inflammatory disease of tooth supportive tissues and is characterized by destruction in periodontal ligaments and alveolar bone besides pocket formation and gingival recession. Rheumatoid arthritis is the most common chroinic inflammatory disease of the joints. The aim of this study was to survey the relationship between periodontitis and rheumatoid arthritis.Materials and Methods: In this cross-sectional-analytical study, 50 rheumatoid arthritis patients forming the case group and 50 healthy individuals as the control group were included. Mean of plaque index, percentage of bleeding sites, mean of probing depth, percentage of sites with probing depth more than 3mm, percentage of sites with attachment loss, and percentage of sites with gingival recession and the number of missing teeth were recorded in both groups. Mean values of each variable were compared between the two groups using t- test. The collected data were statistically analyzed via SPSS on a computer. (?=0/05.Results: Analyzing the data showed that there were no statistically significant differences in the mean of plaque index, percentage of bleeding sites , mean of probing depth, percentage of sites with probing depth more than 3mm, percentage of sites with attachment loss, and percentage of sites with gingival recession, between the case and the control group. The mean of attachment loss (P-value =0.04, mean of gingival recession (P-value =0.02 , and the average number of missing teeth (P-value =0.0001were significantly higher in the rheumatoid arthritis (the case group compared to the control group. Conclusion: periodontal disease (based on the average clinical attachment loss was seen with a higher severity among patients with rheumatoid arthritis. Therefore, regular dental examination besides close attention to dental health in patients with rheumatoid arthritis is highly recommended. Key words: Rheumatoid Arthritis, Periodontitis, Attachment loss

P Ghaliani

2010-01-01

217

Modeling susceptibility to periodontitis.  

Science.gov (United States)

Chronic inflammatory diseases like periodontitis have a complex pathogenesis and a multifactorial etiology, involving complex interactions between multiple genetic loci and infectious agents. We aimed to investigate the influence of genetic polymorphisms and bacteria on chronic periodontitis risk. We determined the prevalence of 12 single-nucleotide polymorphisms (SNPs) in immune response candidate genes and 7 bacterial species of potential relevance to periodontitis etiology, in chronic periodontitis patients and non-periodontitis control individuals (N = 385). Using decision tree analysis, we identified the presence of bacterial species Tannerella forsythia, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and SNPs TNF -857 and IL-1A -889 as discriminators between periodontitis and non-periodontitis. The model reached an accuracy of 80%, sensitivity of 85%, specificity of 73%, and AUC of 73%. This pilot study shows that, on the basis of 3 periodontal pathogens and SNPs, patterns may be recognized to identify patients at risk for periodontitis. Modern bioinformatics tools are valuable in modeling the multifactorial and complex nature of periodontitis. PMID:23100272

Laine, M L; Moustakis, V; Koumakis, L; Potamias, G; Loos, B G

2013-01-01

218

Cemental tear: a risk factor in periodontal attachment loss.  

Science.gov (United States)

The objective of this retrospective study was to evaluate the influence of cemental tear as a risk factor in periodontal attachment loss. Seventeen extracted, single-rooted teeth showing loss of attachment and having one cemental tear surface and one opposite intact surface were examined. The teeth were stained in 0.1% toluidine blue to visualize attached periodontal ligament remnants and examined in a light microscope under incident light. On each tooth, loss of attachment was measured along the long axis of the root from the cemento-enamel junction to the most coronal level of the periodontal ligament on intact as well as on defect surfaces. Cemental tear surfaces demonstrated a significantly greater loss of attachment than opposite intact surfaces (P < 0.0001). In one specimen, the cemental tear fragment was partially attached to the root after the extraction procedure. This specimen was processed for light microscopy to determine the location of the cemental tear fracture. Histological examination clearly revealed that the split between the root and the fragment had occurred along the cemento-dentinal border. The results indicate that cemental tear should be considered as a possible etiologic entity in localized rapid periodontal breakdown. PMID:8794968

Leknes, K N; Lie, T; Selvig, K A

1996-06-01

219

An investigation on clinical, radiological and biochemical methods for assessing periodontitis activity  

International Nuclear Information System (INIS)

In order to recognize in which stage rapidly progressing destruction of periodontal ligament fibers occurs, a number of diagnostic methods are studied in this thesis. It turns out that the actual much utilized clinical methods can not be improved while radiological and biochemical diagnositic methods are much more promising. 106 refs.; 20 figs.; 36 tabs

220

REINFORCING POTENTIAL OF JUTE PULP WITH TREMA ORIENTALIS (NALITA PULP  

Directory of Open Access Journals (Sweden)

Full Text Available Two morphologically different pulps, a long-fiber jute pulp from a soda-AQ process and a short-fiber Trema orientalis pulp from a kraft process, were evaluated and compared for their reinforcing potential. T. orientalis pulp needed less beating energy than jute pulp at the same drainage resistance. Addition of jute fiber pulp to the T. orientalis pulp increased tear strength. Sheet density of pulp blends was increased with the increase of beating degree of both pulps and the proportion of T. orientalis pulp. Tensile index and burst index of blended pulp were increased when the beating degree and proportion of T. orientalis pulp increased.

Sabina Rawshan

2009-08-01

221

Diabetes and periodontitis  

OpenAIRE

The main aim of this review is to update the reader with practical knowledge concerning the relationship between diabetes mellitus and periodontal diseases. Exclusive data is available on the association between these two chronic diseases till date. Articles published on this relationship often provide the knowledge of definitions of diabetes mellitus and periodontal diseases, prevalence, extent, severity of periodontal disease, complications of diabetes along with the possible underlying mec...

Deshpande Kalyani; Jain Ashish; Sharma RaviKant; Prashar Savita; Jain Rajni

2010-01-01

222

The influence of cellular source on periodontal regeneration using calcium phosphate coated polycaprolactone scaffold supported cell sheets.  

Science.gov (United States)

Cell-based therapy is considered a promising approach to achieving predictable periodontal regeneration. In this study, the regenerative potential of cell sheets derived from different parts of the periodontium (gingival connective tissue, alveolar bone and periodontal ligament) were investigated in an athymic rat periodontal defect model. Periodontal ligament (PDLC), alveolar bone (ABC) and gingival margin-derived cells (GMC) were obtained from human donors. The osteogenic potential of the primary cultures was demonstrated in vitro. Cell sheets supported by a calcium phosphate coated melt electrospun polycaprolactone (CaP-PCL) scaffold were transplanted to denuded root surfaces in surgically created periodontal defects, and allowed to heal for 1 and 4 weeks. The CaP-PCL scaffold alone was able to promote alveolar bone formation within the defect after 4 weeks. The addition of ABC and PDLC sheets resulted in significant periodontal attachment formation. The GMC sheets did not promote periodontal regeneration on the root surface and inhibited bone formation within the CaP-PCL scaffold. In conclusion, the combination of either PDLC or ABC sheets with a CaP-PCL scaffold could promote periodontal regeneration, but ABC sheets were not as effective as PDLC sheets in promoting new attachment formation. PMID:24120045

Dan, Hongxia; Vaquette, Cédryck; Fisher, Anthony G; Hamlet, Stephen M; Xiao, Yin; Hutmacher, Dietmar W; Ivanovski, Saso

2014-01-01

223

Normalization of periodontal tissues in osteopetrotic mib mutant rats, treated with CSF-1  

Science.gov (United States)

The osteopetrotic mib mutation in rats causes defects in the skeletal bone tissue in young animals. These defects, i.e. slow bone remodelling, changes in both crystallinity and mineral content, are transient and undergo normalization, even without any treatment in 6-wk-old animals. Treatment with CSF-1 (colony stimulating factor-1) accelerates the normalization process in skeletal bones. The periodontal tissues around the apices of incisors show abnormalities caused by the slow remodelling process of the mandible bone tissue, the deficiency of osteoclasts and their abnormal morphology, as well as the disorganization of periodontal ligament fibres. In contrast to the skeletal tissues, these abnormalities would not undergo spontaneous normalization. Under treatment with colony stimulating factor 1 (CSF-1), the primitive bone trabeculae of mandible are resorbed and the normalization of the number of osteoclasts and their cytology occurs. The organization of the periodontal ligament fibres is partially restored, resembling the histological structure of the normal one.

Wojtowicz, A.; Yamauchi, M.; Sotowski, R.; Ostrowski, K.

1998-01-01

224

Microbiology of aggressive periodontitis.  

Science.gov (United States)

For decades, Aggregatibacter actinomycetemcomitans has been considered the most likely etiologic agent in aggressive periodontitis. Implementation of DNA-based microbiologic methodologies has considerably improved our understanding of the composition of subgingival biofilms, and advanced open-ended molecular techniques even allow for genome mapping of the whole bacterial spectrum in a sample and characterization of both the cultivable and not-yet-cultivable microbiota associated with periodontal health and disease. Currently, A. actinomycetemcomitans is regarded as a minor component of the resident oral microbiota and as an opportunistic pathogen in some individuals. Its specific JP2 clone, however, shows properties of a true exogenous pathogen and has an important role in the development of aggressive periodontitis in certain populations. Still, limited data exist on the impact of other microbes specifically in aggressive periodontitis. Despite a wide heterogeneity of bacteria, especially in subgingival samples collected from patients, bacteria of the red complex in particular, and those of the orange complex, are considered as potential pathogens in generalized aggressive periodontitis. These types of bacterial findings closely resemble those found for chronic periodontitis, representing a mixed polymicrobial infection without a clear association with any specific microorganism. In aggressive periodontitis, the role of novel and not-yet-cultivable bacteria has not yet been elucidated. There are geographic and ethnic differences in the carriage of periodontitis-associated microorganisms, and they need to be taken into account when comparing study reports on periodontal microbiology in different study populations. In the present review, we provide an overview on the colonization of potential periodontal pathogens in childhood and adolescence, and on specific microorganisms that have been suspected for their role in the initiation and progression of aggressive forms of periodontal disease. PMID:24738586

Könönen, Eija; Müller, Hans-Peter

2014-06-01

225

Novel application of stem cell-derived factors for periodontal regeneration  

Energy Technology Data Exchange (ETDEWEB)

Highlights: Black-Right-Pointing-Pointer Mesenchymal stem cells (MSCs) secrete a variety of cytokines. Black-Right-Pointing-Pointer Cytokines were detected in conditioned medium from cultured MSCs (MSC-CM). Black-Right-Pointing-Pointer MSC-CM enhanced activation of dog MSCs and periodontal ligament cells. Black-Right-Pointing-Pointer MSC-CM significantly promoted alveolar bone and cementum regeneration. Black-Right-Pointing-Pointer Multiple cytokines contained in MSC-CM promote periodontal regeneration. -- Abstract: The effect of conditioned medium from cultured mesenchymal stem cells (MSC-CM) on periodontal regeneration was evaluated. In vitro, MSC-CM stimulated migration and proliferation of dog MSCs (dMSCs) and dog periodontal ligament cells (dPDLCs). Cytokines such as insulin-like growth factor, vascular endothelial growth factor, transforming growth factor-{beta}1, and hepatocyte growth factor were detected in MSC-CM. In vivo, one-wall critical-size, intrabony periodontal defects were surgically created in the mandible of dogs. Dogs with these defects were divided into three groups that received MSC-CM, PBS, or no implants. Absorbable atelo-collagen sponges (TERUPLUG Registered-Sign ) were used as a scaffold material. Based on radiographic and histological observation 4 weeks after transplantation, the defect sites in the MSC-CM group displayed significantly greater alveolar bone and cementum regeneration than the other groups. These findings suggest that MSC-CM enhanced periodontal regeneration due to multiple cytokines contained in MSC-CM.

Inukai, Takeharu, E-mail: t-inukai@med.nagoya-u.ac.jp [Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine (Japan); Katagiri, Wataru, E-mail: w-kat@med.nagoya-u.ac.jp [Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine (Japan); Yoshimi, Ryoko, E-mail: lianzi@med.nagoya-u.ac.jp [Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine (Japan); Osugi, Masashi, E-mail: masashi@med.nagoya-u.ac.jp [Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine (Japan); Kawai, Takamasa, E-mail: takamasa@med.nagoya-u.ac.jp [Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine (Japan); Hibi, Hideharu, E-mail: hibihi@med.nagoya-u.ac.jp [Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine (Japan); Ueda, Minoru, E-mail: mueda@med.nagoya-u.ac.jp [Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine (Japan)

2013-01-11

226

Novel application of stem cell-derived factors for periodontal regeneration  

International Nuclear Information System (INIS)

Highlights: ? Mesenchymal stem cells (MSCs) secrete a variety of cytokines. ? Cytokines were detected in conditioned medium from cultured MSCs (MSC-CM). ? MSC-CM enhanced activation of dog MSCs and periodontal ligament cells. ? MSC-CM significantly promoted alveolar bone and cementum regeneration. ? Multiple cytokines contained in MSC-CM promote periodontal regeneration. -- Abstract: The effect of conditioned medium from cultured mesenchymal stem cells (MSC-CM) on periodontal regeneration was evaluated. In vitro, MSC-CM stimulated migration and proliferation of dog MSCs (dMSCs) and dog periodontal ligament cells (dPDLCs). Cytokines such as insulin-like growth factor, vascular endothelial growth factor, transforming growth factor-?1, and hepatocyte growth factor were detected in MSC-CM. In vivo, one-wall critical-size, intrabony periodontal defects were surgically created in the mandible of dogs. Dogs with these defects were divided into three groups that received MSC-CM, PBS, or no implants. Absorbable atelo-collagen sponges (TERUPLUG®) were used as a scaffold material. Based on radiographic and histological observation 4 weeks after transplantation, the defect sites in the MSC-CM group displayed significantly greater alveolar bone and cementum regeneration than the other groups. These findings suggest that MSC-CM enhanced periodontal regeneration due to multiple cytokines contained in MSC-CM.

227

Determinantes del diagnóstico periodontal Determinants of periodontal diagnosis  

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Full Text Available Un correcto diagnóstico periodontal es necesario para la realización de una terapia periodontal exitosa en nuestro paciente. Entendiendo que la enfermedad periodontal es un proceso infeccioso-inflamatorio, diferentes variables se deben analizar clínicamente para determinar el diagnóstico. El diagnóstico entonces es un análisis concienzudo de la expresión clínica de la enfermedad, desde gingivitis hasta periodontitis. Este artículo analiza los determinantes más importantes del diagnóstico periodontal utilizados en la práctica clínica diaria.The correct diagnosis of periodontal disease is a pre-requisite for an appropriate periodontal treatment. Periodontal disease is an infectious-inflammatory process that affects different clinical variables that must be analyzed before reaching the diagnosis. The diagnosis should be a carefully performed analysis of the clinical expression of the disease, from gingivitis to periodontitis. This article reviews the most important determinants of periodontal diagnosis.

JE Botero

2010-08-01

228

CT of hepatoduodenal ligament  

International Nuclear Information System (INIS)

In determining the operability, especially of super-radical approach to malignancies of biliary tract, it is very important to confirm the direct infiltration or metastasis to the lymphnodes in the hepatoduodenal ligament. To date, the information about hepatoduodnal ligament obtained by conventional means such as angiography, cholangiography, etc, has been limited. In the present study, we performed some analysis on CT findings of hepatoduodenal ligament produced by malignant tumors of the biliary tract. Forty-two biliary tract malignancies (24 cases of bile duct cancer, 18 cases of gallbladder cancer) showed tumor shadows in the region of hepatoduodenal ligament and/or bile duct dilatation on CT : Ten bile duct (41,7%) and 5 gallbladder primary (27.8%). Of 19 cases with bile duct cancer in hepatoduodenal ligament, 10 (52.6%) had the tumor shadows. In one case, the shadow within the ligament was suggestive of primary tumor. Of these 10 cases, only one was resectable by surgery. With gallbladder cancer, the shadows were the cancer infiltration and/or lymphnode metastasis. All cases bile duct cancer and 11 cases gallbladder cancer (61.1%) showed dilatations of bile duct in various degrees. As a preoperative examination, CT was thought to be the most useful in confirming the cancer infiltration and/or lymphnode metastasis in the hepatoduodenal ligament. (author)

229

Expression of RANKL and OPG mRNA in periodontal disease: possible involvement in bone destruction.  

Science.gov (United States)

Periodontitis is a complex, multifactorial process affected by bacterial plaque-components and host defense mechanisms. Inflammation of the periodontitium may lead the destruction of the underlying ligament and alveolar bone. Receptor activator of NF-kappaB ligand (RANKL), a novel TNF receptor-related protein is an important factor for osteoclast differentiation and activation. Given osteolysis by osteoclast has been demonstrated in periodontitis, we hypothesized that RANKL expression may be associated with bone destruction in periodontitis. We used semi-quantitative RT-PCR to compare the gene expression of RANKL and osteoprogerin (OPG), a decoy receptor of RANKL, between moderate and advanced periodontitis, and healthy subjects. The level of RANKL mRNA was highest in advanced periodontitis. In contrast, the level of OPG mRNA in both advanced and moderate periodontitis was lower than that in the healthy group. It appears that the ratio of RANKL to OPG mRNA in periodontitis has increased. To determine the localization of RANKL gene transcripts in gingival tissue at the cellular level, in situ hybridization was performed using digoxigenin-labeled specific riboprobes. RANKL mRNA was expressed in inflammatory cells, mainly lymphocyte and macrophages. In addition, proliferating epithelium in the vicinity of inflammatory cells expressed high levels of RANKL mRNA. In short, our data suggest that up regulation of RANKL mRNA in both inflammatory cells and epithelium may be associated with the activation of osteoclastic bone destruction in periodontitis. PMID:12469211

Liu, D; Xu, J K; Figliomeni, L; Huang, L; Pavlos, N J; Rogers, M; Tan, A; Price, P; Zheng, M H

2003-01-01

230

An Ultrasonographic Periodontal Probe  

Science.gov (United States)

Periodontal disease, commonly known as gum disease, affects millions of people. The current method of detecting periodontal pocket depth is painful, invasive, and inaccurate. As an alternative to manual probing, an ultrasonographic periodontal probe is being developed to use ultrasound echo waveforms to measure periodontal pocket depth, which is the main measure of periodontal disease. Wavelet transforms and pattern classification techniques are implemented in artificial intelligence routines that can automatically detect pocket depth. The main pattern classification technique used here, called a binary classification algorithm, compares test objects with only two possible pocket depth measurements at a time and relies on dimensionality reduction for the final determination. This method correctly identifies up to 90% of the ultrasonographic probe measurements within the manual probe's tolerance.

Bertoncini, C. A.; Hinders, M. K.

2010-02-01

231

Tabaquismo y enfermedad periodontal  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Se realizó un estudio epidemiológico transversal en 96 fumadores que acudieron al examen médico y control de salud en el Hospital Militar "Comandante Manuel Fajardo Rivero" de Santa Clara, en el período comprendido de enero a junio del 2001. Para el examen de los fumadores se utilizó el índice de ne [...] cesidad de tratamiento periodontal en la comunidad; los objetivos de este fueron determinar la prevalencia y gravedad de la enfermedad periodontal según la edad del paciente y los años que lleva fumando, así como las necesidades de tratamiento periodontal en los pacientes estudiados. Se pudo observar que el grupo de edad más afectado por la enfermedad fue el de 45 a 54 años, y las personas que llevan más de 40 años fumando padecen de periodontitis más severas. Los fumadores que consumen más de 10 cigarrillos o 3 tabacos diarios son los que necesitan tratamiento periodontal complejo. Abstract in english An epidemiological cross-sectional study was performed on 96 smokers who went to undergo medical examination and health control tests in "Manuel Fajardo Rivero" Military Hospital in Santa Clara from January to June, 2001. For the examination of smokers, the periodontal treatment need index in the co [...] mmunity was used. The objectives of this paper were to determine the prevalence and seriousness of periodontal diseases according to the age of patients and years of smoking as well as the needs of periodontal treatment of the studied patients. It was observed that the most affected age group was 45-54 years and people who have been smoking for over 40 years suffered from the most severe type of periodontitis. The smokers who daily smoke more than 10 cigarettes or 3 cigars need complex periodontal treatment.

Bárbara, Toledo Pimental; María Elena, González Díaz; María Susana, Alfonso Tarraú; Aleida, Pérez Carrillo; María Lucía, Rodríguez Linares.

2002-06-01

232

Refining of Polysulfide Pulps  

Directory of Open Access Journals (Sweden)

Full Text Available This study compares the modified kraft process, polysulfide pulping, one of the methods to obtain higher pulp yield, with conventional kraft method. More specifically, the study focuses on the refining effects of polysulfide pulp, which is an area with limited literature. Physical, mechanical and chemical properties of kraft and polysulfide pulps (4% elemental sulfur addition to cooking digester cooked under the same conditions were studied as regards to their behavior under various PFI refining (0, 3000, 6000, 9000 revs.. Polysulfide (PS pulping, compared to the kraft method, resulted in higher pulp yield and higher pulp kappa number. Polysulfide also gave pulp having higher tensile and burst index. However, the strength of polysulfide pulp, tear index at a constant tensile index, was found to be 15% lower as compared to the kraft pulp. Refining studies showed that moisture holding ability of chemical pulps mostly depends on the chemical nature of the pulp. Refining effects such as fibrillation and fine content did not have a significant effect on the hygroscopic behavior of chemical pulp.

Yalcin Copur

2007-01-01

233

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

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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 acids (5 .Cell counting was done by Trypan Blue dye exclusion method and the cells were seeded in 6 well culture plates. The plates with cells were incubated at 37?C with 5% CO2 for varying periods from 14 days-28 days. The cells were observed daily and media change was done every three days. RESULTS: Viable Dental Pulp tissue-cells were obtained after transportation of up to 48 hrs and the in vitro growth of cells was initially slow but colonies were identified from the 10th day onwards. The cells were harvested at different intervals of 14-28 days for each sample based on their growth and subjected to H & E staining .The H & E staining of the cultured cells of all the samples showed positive resultsCONCLUSION: We are able to transport extracted teeth and derive viable dental pulp tissue cells after enzymatic digestion and multiply them in culture after a maximum of 48 hrs after transportation. The cells could be grown in culture with a morphology resembling dental pulp stem cells while in culture expansion and in H&E studies. Further characterization of the cells is necessary to confirm their Stemness. References1.Gronthos S, Mankani M, Brahim J, Robey PG, Shi S. Postnatal human dental pulp stem cells (DPSCs in vitro and in vivo. Proc Natl Acad Sci U S A. 20002.Nosrat IV, Widenfalk J, Olson L, Nosrat CA. Dental pulp cells produce neurotrophic factors, interact with trigeminal neurons in vitro, and rescue motoneurons after spinal cord injury. Dev Biol. 2001 Oct 3.Iohara K, Zheng L, Ito M, Tomokiyo A, Matsushita K, Nakashima M. Side population cells isolated from porcine dental pulp tissue with self-renewal and multipotency for dentinogenesis, chondrogenesis, adipogenesis, and neurogenesis. Stem Cells. 2006 Nov4.Gandia C, Armiñan A, García-Verdugo JM, Lledó E, Ruiz A, Miñana MD, Sanchez-Torrijos J, Payá R, Mirabet V, Carbonell-Uberos F, Llop M, Montero JA, Sepúlveda P. Human dental pulp stem cells improve left ventricular function, induce angiogenesis, and reduce infarct size in rats with acute myocardial infarction. Stem Cells. 2008 Mar5.Kerkis I, Kerkis A

Preethy SP

2010-01-01

234

Inframammary crease ligament.  

Science.gov (United States)

This study was designed to clarify and define the anatomic components of the inframammary crease in the female breast. Thirteen blunt dissections of the female breast were performed in cadavers and one dissection was performed in a living patient undergoing mastectomy. During the course of these dissections, a ligament was identified. This ligament originates from the fifth rib periosteum medially and the fascia between the fifth and sixth ribs laterally. The ligament inserts distally into the deep dermis of the inframammary skin fold. Histologic sections confirmed the proximal bony origin of this structure. In three cadavers, the contralateral breast was studied as it pertains to transaxillary subpectoral mammaplasty using the Agis-Dingman dissector (Padgett Instruments, Kansas City, Mo.). If too forceful a sweep were made in the inferior portion of the dissection, the ligament would be disrupted. This separation of the ligament from its origin could lead to the "double-bubble" phenomenon. Further, the horizontal position of this ligament determines the medial versus lateral fall of the ptotic breast. PMID:7870774

Bayati, S; Seckel, B R

1995-03-01

235

Ultrasound in periodontics  

Directory of Open Access Journals (Sweden)

Full Text Available Ultrasonic instruments were introduced in periodontal therapy in 1955. Approximately 50 years later, their effects on the teeth and periodontium have become much clearer. Currently, ultrasonic instruments are frequently used in daily practice. Most of these instruments work according to the magnetostrictive or reciprocal piezo-electric principle. Though, they are mainly used for routine prophylaxis, there are various other functions of these in the field of Periodontics. This article explains the principle and mechanism of action of ultrasonic instruments with their various applications in Periodontics.

Sapna N

2010-10-01

236

Periodontal bone lesions  

International Nuclear Information System (INIS)

In the course of life the periodontum is subject to changes which may be physiological or pathological. Intraoral radiographs give insight into the hard structures of the dentomaxillar region and provides information on lesions in the bone of the periodontum in that they show radiopacities and radiolucencies caused by such lesions. In this thesis the relation is investigated between the true shape and dimensions of periodontal bone lesions and their radiographic images. A method is developed and tested of making standardized and reproducible radiographs suitable for longitudinal studies of periodontal lesions. Also the possibility is demonstrated of an objective and reproducible interpretation of radiographic characteristics of periodontal bone lesions. (Auth.)

237

Treatment of aggressive periodontitis.  

Science.gov (United States)

Despite etiological differences between aggressive and chronic periodontitis, the treatment concept for aggressive periodontitis is largely similar to that for chronic periodontitis. The goal of treatment is to create a clinical condition that is conducive to retaining as many teeth as possible for as long as possible. When a diagnosis has been made and risk factors have been identified, active treatment is commenced. The initial phase of active treatment consists of mechanical debridement, either alone or supplemented with antimicrobial drugs. Scaling and root planing has been shown to be effective in improving clinical indices, but does not always guarantee long-term stability. Antimicrobials can play a significant role in controlling aggressive periodontitis. Few studies have been published on this subject for localized aggressive periodontitis, but generalized aggressive periodontitis has been subject to more scrutiny. Studies have demonstrated that systemic antibiotics as an adjuvant to scaling and root planing are more effective in controlling disease compared with scaling and root planing alone or with supplemental application of local antibiotics or antiseptics. It has also become apparent that antibiotics ought to be administered with, or just after, mechanical debridement. Several studies have shown that regimens of amoxicillin combined with metronidazole or regimens of clindamycin are the most effective and are preferable to regimens containing doxycycline. Azithromycin has been shown to be a valid alternative to the regimen of amoxicillin plus metronidazole. A limited number of studies have been published on surgical treatment in patients with aggressive periodontitis, but the studies available show that the effect can be comparable with the effect on patients with chronic periodontitis, provided that proper oral hygiene is maintained, a strict maintenance program is followed and modifiable risk factors are controlled. Both access surgery and regenerative techniques have shown good results in patients with aggressive periodontitis. Once good periodontal health has been obtained, patients must be enrolled in a strict maintenance program that is directed toward controlling risk factors for disease recurrence and tooth loss. The most significant risk factors are noncompliance with regular maintenance care, smoking, high gingival bleeding index and poor plaque control. There is no evidence to suggest that daily use of antiseptic agents should be part of the supportive periodontal therapy for aggressive periodontitis. PMID:24738589

Teughels, Wim; Dhondt, Rutger; Dekeyser, Christel; Quirynen, Marc

2014-06-01

238

Detection of periodontal markers in chronic periodontitis.  

Science.gov (United States)

The aim was to compare the detection frequency of periodontopathogens by using the Pado Test 4.5 and checkerboard DNA-DNA hybridization technique in chronic periodontitis patients.Thirty patients with chronic periodontitis were tested cross-sectionally with DNA/RNA oligogenomic probe method (IAI Pado Test 4.5) and DNA/DNA whole genomic probe (checkerboard) method. Samples were taken by two paper points at the deepest site in each of the four quadrants and pooled into one sample for each of the two methods. The samples were sent to the two laboratories (IAI, Zuchwil, Switzerland, and Oral Microbiology Laboratory, University of Gothenburg, Sweden) and were analyzed in a routine setting for the presence and amount of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola.While Pado Test 4.5 detected the four periodontal pathogens in 11 (36.7%) of the patients, the checkerboard method showed presence in all patients (100%) using the lower score (Score 1 corresponding to 10(4) bacterial cells) and 16 (53.3%) using a higher treshold (score 3 corresponding to between >10(5) and 10(6) cells).The results of the present study showed low agreement for a positive microbiological outcome using the two diagnostic methods. It was also concluded that microbiological analysis in practice should include a larger number of bacterial species to better serve as markers for a diseased associated flora in chronic periodontitis cases. PMID:21769304

Leonhardt, Asa; Carlén, Anette; Bengtsson, Lisbeth; Dahlén, Gunnar

2011-01-01

239

In Vitro Simulation of Tooth Mobility Resulting from Periodontal Attachment Loss  

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Full Text Available In our previous studies, we developed the normal periodontal ligament index (nPLI and the residual periodontal ligament index (rPLI, to estimate residual periodontal ligament support for individual teeth during treatment planning for partially edentulous patients. The purpose of the current in vitro study was to analyze tooth mobility resulting from periodontal attachment loss, and to determine the application range of both nPLI and rPLI. The association of horizontal load-displacement and conditions of attachment loss was measured in triplicate for each anatomical tooth model at 10-minute intervals, using a universal tester at a crosshead speed of 0.05 mm/min, and a load of 0.1 N. The conditions of attachment loss were: (I 0 mm (cementoenamel junction, (II 2 mm attachment level, and (III two-thirds, and (IV one-half lengths of normal attachment. Except for the upper first molar, lower lateral incisor, lower first premolar, and the lower first molar, the displacement of each tooth type was increased significantly relative to Level I (P P < 0.01. The results indicated that nPLI at two-thirds of normal attachment and greater, and rPLI at less than two-thirds of normal attachment should be applied, respectively.

Yasuhiko Abe

2014-06-01

240

Types of Periodontal Disease  

Science.gov (United States)

... the whole body. These include certain types of leukemias, neutropenias and genetic disorders. This type of periodontitis ... likely in people who smoke or have poor nutrition, psychological stress or HIV infection. The treatment for ...

241

Periodontal disease and halitosis  

International Nuclear Information System (INIS)

Halitosis is a general term used to describe an unpleasant or offensive odor emanating from the oral cavity. It is a condition that has health and social implications in the life of those who suffer from it. The origin of halitosis is related to both systemic and oral conditions although the oral causes predominate. Volatile sulfur compound is the primary gas responsible for halitosis. They are formed as a result of gram-negative bacterial putrefaction. The major sites for oral halitosis are the dorsum of the tongue and periodontal pockets. There is a correlation between the amount of plaque on the tongue and periodontitis with the severity of halitosis. The aim of this article was to review the data and correlate periodontitis with severity of halitosis and the effect of halitosis- inducing factors on the progress of periodontal diseases. (author)

242

Proliferation of periodontal squamous epithelium in mink fed 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).  

Science.gov (United States)

The maxilla and mandible from 2 adult female mink fed 5.0 ppb 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for 6 mo were grossly unremarkable, but histologically had nests of squamous epithelium within the periodontal ligament. There was osteolysis of the adjacent alveolar bone. PMID:10750171

Render, J A; Hochstein, J R; Aulerich, R J; Bursian, S J

2000-04-01

243

Obesity and periodontal disease  

OpenAIRE

Obesity is characterized by the abnormal or excessive deposition of fat in the adipose tissue. Its consequences go far beyond adverse metabolic effects on health, causing an increase in oxidative stress, which leads not only to endothelial dysfunction but also to negative effects in relation to periodontitis, because of the increase in proinflammatory cytokines. Thus obesity appears to participate in the multifactorial phenomenon of causality of periodontitis through the increased production ...

Jagannathachary Sunitha; Kamaraj Dinesh

2010-01-01

244

Effects of concomitant use of fibroblast growth factor (FGF)-2 with beta-tricalcium phosphate ({beta}-TCP) on the beagle dog 1-wall periodontal defect model  

Energy Technology Data Exchange (ETDEWEB)

Research highlights: {yields} Concomitant use of FGF-2 and {beta}-TCP (an osteo-conductive scaffold) significantly promotes periodontal regeneration in the severe periodontitis model (1-wall defect model) of beagle dog. {yields} FGF-2 enhanced new bone formation via {beta}-TCP at the defects. {yields} In particular, FGF-2 dramatically regenerated new periodontal ligament and cementum formations at the defects, that is one of the most important healing outcomes during the process of periodontal regeneration. {yields} Epithelial downgrowth (undesirable wound healing) was decreased by administration of FGF-2. {yields} This manuscript indicates for the first time that concomitant use of FGF-2 and {beta}-TCP is efficacious in regenerating periodontal tissue following severe destruction of the tissue by progression of periodontitis. -- Abstract: The effects of concomitant use of fibroblast growth factor-2 (FGF-2) and beta-tricalcium phosphate ({beta}-TCP) on periodontal regeneration were investigated in the beagle dog 1-wall periodontal defect model. One-wall periodontal defects were created in the mesial portion of both sides of the mandibular first molars, and 0.3% FGF-2 plus {beta}-TCP or {beta}-TCP alone was administered. Radiographic evaluation was performed at 0, 3, and 6 weeks. At 6 weeks, the periodontium with the defect site was removed and histologically analyzed. Radiographic findings showed that co-administration of FGF-2 significantly increased bone mineral contents of the defect sites compared with {beta}-TCP alone. Histologic analysis revealed that the length of the regenerated periodontal ligament, the cementum, distance to the junctional epithelium, new bone height, and area of newly formed bone were significantly increased in the FGF-2 group. No abnormal inflammatory response or ankylosis was observed in either group. These findings indicate the efficacy of concomitant use of FGF-2 and {beta}-TCP as an osteoconductive material for periodontal regeneration following severe destruction by progressive periodontitis.

Anzai, Jun, E-mail: anzai_jun@kaken.co.jp [Pharmacology Department, Central Research Laboratories, Kaken Pharmaceutical Co., Ltd., 14, Shinomiya, Minamigawara-cho, Yamashina-ku, Kyoto 607-8042 (Japan); Department of Periodontology, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Kitamura, Masahiro, E-mail: kitamura@dent.osaka-u.ac.jp [Department of Periodontology, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Nozaki, Takenori, E-mail: tnozaki@dent.osaka-u.ac.jp [Department of Periodontology, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Nagayasu, Toshie, E-mail: nagayasu_toshie@kaken.co.jp [Pharmacology Department, Central Research Laboratories, Kaken Pharmaceutical Co., Ltd., 14, Shinomiya, Minamigawara-cho, Yamashina-ku, Kyoto 607-8042 (Japan); Terashima, Akio, E-mail: terashima_akio@kaken.co.jp [Pharmacology Department, Central Research Laboratories, Kaken Pharmaceutical Co., Ltd., 14, Shinomiya, Minamigawara-cho, Yamashina-ku, Kyoto 607-8042 (Japan); Asano, Taiji, E-mail: asano_taiji@kaken.co.jp [Pharmacology Department, Central Research Laboratories, Kaken Pharmaceutical Co., Ltd., 14, Shinomiya, Minamigawara-cho, Yamashina-ku, Kyoto 607-8042 (Japan); Murakami, Shinya, E-mail: ipshinya@dent.osaka-u.ac.jp [Department of Periodontology, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871 (Japan)

2010-12-17

245

Effects of concomitant use of fibroblast growth factor (FGF)-2 with beta-tricalcium phosphate (?-TCP) on the beagle dog 1-wall periodontal defect model  

International Nuclear Information System (INIS)

Research highlights: ? Concomitant use of FGF-2 and ?-TCP (an osteo-conductive scaffold) significantly promotes periodontal regeneration in the severe periodontitis model (1-wall defect model) of beagle dog. ? FGF-2 enhanced new bone formation via ?-TCP at the defects. ? In particular, FGF-2 dramatically regenerated new periodontal ligament and cementum formations at the defects, that is one of the most important healing outcomes during the process of periodontal regeneration. ? Epithelial downgrowth (undesirable wound healing) was decreased by administration of FGF-2. ? This manuscript indicates for the first time that concomitant use of FGF-2 and ?-TCP is efficacious in regenerating periodontal tissue following severe destruction of the tissue by progression of periodontitis. -- Abstract: The effects of concomitant use of fibroblast growth factor-2 (FGF-2) and beta-tricalcium phosphate (?-TCP) on periodontal regeneration were investigated in the beagle dog 1-wall periodontal defect model. One-wall periodontal defects were created in the mesial portion of both sides of the mandibular first molars, and 0.3% FGF-2 plus ?-TCP or ?-TCP alone was administered. Radiographic evaluation was performed at 0, 3, and 6 weeks. At 6 weeks, the periodontium with the defect site was removed and histologically analyzed. Radiographic findings showed that co-administration of FGF-2 significantly increased bone mineral contents of the defect sites compared with ?-TCP alone. Histologic analysis revealed that the length of the regenerated periodontal ligament, the cementum, distance to the junctional epithelium, new bone height, and area of newly formed bone were significantly increased in the FGF-2 group. No abnormal inflammatory response or ankylosis was observed in either group. These findings indicate the efficacy of concomitant use of FGF-2 and ?-TCP as an osteoconductive material for periodontal regeneration following severe destruction by progressive periodontitis.

246

Obesity and periodontal disease.  

Science.gov (United States)

Obesity is characterized by the abnormal or excessive deposition of fat in the adipose tissue. Its consequences go far beyond adverse metabolic effects on health, causing an increase in oxidative stress, which leads not only to endothelial dysfunction but also to negative effects in relation to periodontitis, because of the increase in proinflammatory cytokines. Thus obesity appears to participate in the multifactorial phenomenon of causality of periodontitis through the increased production of reactive oxygen species. The possible causal relationship between obesity and periodontitis and potential underlying biological mechanisms remain to be established; however, the adipose tissue actively secretes a variety of cytokines and hormones that are involved in inflammatory processes, pointing toward similar pathways involved in the pathophysiology of obesity, periodontitis and related inflammatory diseases. So the aim of this article is to get an overview of the association between obesity and periodontitis and to review adipose-tissue - derived hormones and cytokines that are involved in inflammatory processes and their relationship to periodontitis. PMID:21691545

Jagannathachary, Sunitha; Kamaraj, Dinesh

2010-04-01

247

Obesity and periodontal disease  

Directory of Open Access Journals (Sweden)

Full Text Available Obesity is characterized by the abnormal or excessive deposition of fat in the adipose tissue. Its consequences go far beyond adverse metabolic effects on health, causing an increase in oxidative stress, which leads not only to endothelial dysfunction but also to negative effects in relation to periodontitis, because of the increase in proinflammatory cytokines. Thus obesity appears to participate in the multifactorial phenomenon of causality of periodontitis through the increased production of reactive oxygen species. The possible causal relationship between obesity and periodontitis and potential underlying biological mechanisms remain to be established; however, the adipose tissue actively secretes a variety of cytokines and hormones that are involved in inflammatory processes, pointing toward similar pathways involved in the pathophysiology of obesity, periodontitis and related inflammatory diseases. So the aim of this article is to get an overview of the association between obesity and periodontitis and to review adipose-tissue - derived hormones and cytokines that are involved in inflammatory processes and their relationship to periodontitis.

Jagannathachary Sunitha

2010-01-01

248

Indirect pulp treatment in a permanent molar: case reort of 4-year follow-up  

Directory of Open Access Journals (Sweden)

Full Text Available This case report describes the Indirect Pulp Treatment (IPT of deep caries lesion in a permanent molar. A 16-year-old male patient reported discomfort associated with thermal stimulation on the permanent mandibular left first molar. The radiographs revealed a deep distal caries lesion, very close to the pulp, absence of radiolucencies in the periapical region, and absence of periodontal space thickening. Pulp sensitivity was confirmed by thermal pulp vitality tests. Based on the main complaint and the clinical and radiographic examinations, the treatment plan was established to preserve pulp vitality. Clinical procedures consisted of removing the infected dentin and lining the caries-affected dentin with calcium hydroxide paste. The tooth was provisionally sealed for approximately 60 days. After this period, tooth vitality was confirmed, the remaining carious dentin was removed, and the tooth was restored. At 4-year follow-up, no clinical or radiographic pathological findings were found.

Ticiane Cestari Fagundes

2009-02-01

249

Iatrogenic injury to the pulp in dental procedures: aspects of pathogenesis, management and preventive measures.  

Science.gov (United States)

This review calls attention to the fact that iatrogenic ('dentistogenic') injury to the dental pulp is not an insignificant problem in clinical dentistry. On a short-term basis pulpal inflammatory lesions and hypersensitive teeth are frequently associated with procedures that involve removal of the dental hard tissue structures. Although the pulp is likely to recover, reparative processes induced by the insult may impair pulpal function on a long-term basis. In this paper current concepts regarding pathogenic mechanisms associated with injuries induced in the pulp by restorative and periodontal treatment procedures are reviewed. Aspects of the management of accidental pulp exposures are also described as well as measures to prevent or reduce iatrogenic injuries to the pulp. PMID:2032743

Bergenholtz, G

1991-04-01

250

EFICACIA DEL MOXIFLOXACINO EN PERIODONTITIS Efficacy of Moxifloxacin on periodontitis  

OpenAIRE

Un grupo de bacterias predominantemente Gram.-negativas anaerobias están asociadas con el inicio y progreso de la enfermedad periodontal. Porphyromonas Gingivalis, Aggregatibacter Actinomycetemcomitans y Tannerella forsythensis son los microorganismos fuertemente implicados como agentes etiológicos de la periodontitis. El propósito principal del tratamiento periodontal es reducir la infección, resolver la inflamación y prevenir un deterioro posterior. La terapia antibiótica adjunta pued...

Carlos Martín Ardila Medina; Isabel Cristina Guzmán Zuluaga; María Patricia Arbeláez Montoya

2009-01-01

251

The progress of the periodontal syndrome in the rice rat  

International Nuclear Information System (INIS)

Several morphometric and cellular parameters were studied in the rice rat (Oryzomys palustris). When fed a soft, high carbohydrate diet, a severe periodontal disease occurred, with significant alterations in the morphometric and cellular endpoints observed. Weaned animals were placed on a high carbohydrate diet for periods of 6, 12 or 18 weeks. There was a linear rapid loss of bone by 18 weeks, approaching a 75% loss of original bone. Vascular spaces decreased as the remaining connective tissue became fibrotic in character. The percentage of the interdental test site which was destroyed by periodontal disease increased dramatically over the time of the experiment. The numbers of fibroblasts per mm of bone surface increased slightly at the 18 week period; osteoblasts were unchanged at any period. The numbers of osteoclast nuclei rose dramatically by 12 weeks, and these cell nuclei remained at increased levels at 18 weeks. Also, the numbers of inflammatory cells residing at the bone surface increased greatly by 18 weeks time. Finally, the numbers of 3H-TdR labeled periodontal ligament (PDL) fibroblasts increased significantly at both 12 and 18 weeks time. These cellular changes and their relation to the bone loss due to periodontal disease are discussed. (author)

252

Advanced biomatrix designs for regenerative therapy of periodontal tissues.  

Science.gov (United States)

Periodontitis is an inflammatory disease that causes loss of the tooth-supporting apparatus, including periodontal ligament, cementum, and alveolar bone. A broad range of treatment options is currently available to restore the structure and function of the periodontal tissues. A regenerative approach, among others, is now considered the most promising paradigm for this purpose, harnessing the unique properties of stem cells. How to make full use of the body's innate regenerative capacity is thus a key issue. While stem cells and bioactive factors are essential components in the regenerative processes, matrices play pivotal roles in recapitulating stem cell functions and potentiating therapeutic actions of bioactive molecules. Moreover, the positions of appropriate bioactive matrices relative to the injury site may stimulate the innate regenerative stem cell populations, removing the need to deliver cells that have been manipulated outside of the body. In this topical review, we update views on advanced designs of biomatrices-including mimicking of the native extracellular matrix, providing mechanical stimulation, activating cell-driven matrices, and delivering bioactive factors in a controllable manner-which are ultimately useful for the regenerative therapy of periodontal tissues. PMID:25139364

Kim, J H; Park, C H; Perez, R A; Lee, H Y; Jang, J H; Lee, H H; Wall, I B; Shi, S; Kim, H W

2014-12-01

253

Bone Grafts (Periodontal Regenerative Surgery)  

Science.gov (United States)

Bone Grafts (Periodontal Regenerative Surgery) What Is It? What It's Used For Preparation How It's Done Follow-Up Risks When To ... Before your surgery, you need to have basic periodontal treatment called scaling and root planing. You also ...

254

JAMA Patient Page: Periodontal Disease  

Science.gov (United States)

... of the American Medical Association JAMA PATIENT PAGE Periodontal Disease P eriodontal disease (unhealthy gums and teeth) ... JAMA includes an article about an association between periodontal disease and smoking marijuana. CAUSES FOR MORE INFORMATION • ...

255

MR imaging of cruciate ligaments.  

Science.gov (United States)

Cruciate ligament injuries, and in particular injuries of the anterior cruciate ligament (ACL), are the most commonly reconstructed ligamentous injuries of the knee. As such, accurate preoperative diagnosis is essential in optimal management of patients with cruciate ligament injuries. This article reviews the anatomy and biomechanics of the ACL and posterior cruciate ligament (PCL) and describes the magnetic resonance (MR) imaging appearances of complete and partial tears. Normal postoperative appearances of ACL and PCL reconstructions as well as MR imaging features of postoperative complications will also be reviewed. PMID:25442023

Naraghi, Ali; White, Lawrence M

2014-11-01

256

Acute periodontal lesions.  

Science.gov (United States)

This review provides updates on acute conditions affecting the periodontal tissues, including abscesses in the periodontium, necrotizing periodontal diseases and other acute conditions that cause gingival lesions with acute presentation, such as infectious processes not associated with oral bacterial biofilms, mucocutaneous disorders and traumatic and allergic lesions. A periodontal abscess is clinically important because it is a relatively frequent dental emergency, it can compromise the periodontal prognosis of the affected tooth and bacteria within the abscess can spread and cause infections in other body sites. Different types of abscesses have been identified, mainly classified by their etiology, and there are clear differences between those affecting a pre-existing periodontal pocket and those affecting healthy sites. Therapy for this acute condition consists of drainage and tissue debridement, while an evaluation of the need for systemic antimicrobial therapy will be made for each case, based on local and systemic factors. The definitive treatment of the pre-existing condition should be accomplished after the acute phase is controlled. Necrotizing periodontal diseases present three typical clinical features: papilla necrosis, gingival bleeding and pain. Although the prevalence of these diseases is not high, their importance is clear because they represent the most severe conditions associated with the dental biofilm, with very rapid tissue destruction. In addition to bacteria, the etiology of necrotizing periodontal disease includes numerous factors that alter the host response and predispose to these diseases, namely HIV infection, malnutrition, stress or tobacco smoking. The treatment consists of superficial debridement, careful mechanical oral hygiene, rinsing with chlorhexidine and daily re-evaluation. Systemic antimicrobials may be used adjunctively in severe cases or in nonresponding conditions, being the first option metronidazole. Once the acute disease is under control, definitive treatment should be provided, including appropriate therapy for the pre-existing gingivitis or periodontitis. Among other acute conditions affecting the periodontal tissues, but not caused by the microorganisms present in oral biofilms, infectious diseases, mucocutaneous diseases and traumatic or allergic lesions can be listed. In most cases, the gingival involvement is not severe; however, these conditions are common and may prompt an emergency dental visit. These conditions may have the appearance of an erythematous lesion, which is sometimes erosive. Erosive lesions may be the direct result of trauma or a consequence of the breaking of vesicles and bullae. A proper differential diagnosis is important for adequate management of the case. PMID:24738591

Herrera, David; Alonso, Bettina; de Arriba, Lorenzo; Santa Cruz, Isabel; Serrano, Cristina; Sanz, Mariano

2014-06-01

257

Inactivation of Fam20C in Cells Expressing Type I Collagen Causes Periodontal Disease in Mice  

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Background FAM20C is a kinase that phosphorylates secretory proteins. Previous studies have shown that FAM20C plays an essential role in the formation and mineralization of bone, dentin and enamel. The present study analyzed the loss-of-function effects of FAM20C on the health of mouse periodontal tissues. Methods By crossbreeding 2.3 kb Col 1a1-Cre mice with Fam20Cfl/fl mice, we created 2.3 kb Col 1a1-Cre;Fam20Cfl/fl (cKO) mice, in which Fam20C was inactivated in the cells that express Type I collagen. We analyzed the periodontal tissues in the cKO mice using X-ray radiography, histology, scanning electron microscopy and immunohistochemistry approaches. Results The cKO mice underwent a remarkable loss of alveolar bone and cementum, along with inflammation of the periodontal ligament and formation of periodontal pockets. The osteocytes and lacuno-canalicular networks in the alveolar bone of the cKO mice showed dramatic abnormalities. The levels of bone sialoprotein, osteopontin, dentin matrix protein 1 and dentin sialoprotein were reduced in the Fam20C-deficient alveolar bone and/or cementum, while periostin and fibrillin-1 were decreased in the periodontal ligament of the cKO mice. Conclusion Loss of Fam20C function leads to periodontal disease in mice. The reduced levels of bone sialoprotein, osteopontin, dentin matrix protein 1, dentin sialoprotein, periostin and fibrillin-1 may contribute to the periodontal defects in the Fam20C-deficient mice. PMID:25479552

Liu, Peihong; Zhang, Hua; Liu, Chao; Wang, Xiaofang; Chen, Li; Qin, Chunlin

2014-01-01

258

Aterosclerosis en sujetos con periodontitis / Association between atherosclerosis and periodontitis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish [...] Abstract in english Background: Chronic infl ammation and infections are involved in the development and progression of atherosclerotic vascular disease. Aim: To evaluate the association between periodontitis and early atherosclerosis. Material and Methods: Fifty-three subjects who received periodontal treatment and re [...] gular maintenance for at least 10 years, and 55 subjects with periodontitis but without a history of periodontal treatment were studied. Carotid artery intima-media wall thickness (CIMT) was measured with high-resolution B-mode ultrasonography. A blood sample was obtained to measure high sensitivity C-reactive protein, fibrinogen, lipoprotein cholesterol, leukocyte count and erythrocyte sedimentation rate. Covariates included age, gender, smoking, level of education, body mass index and physical activity. The benzoyl-DL-arginine-naphthylamide (BANA) test was used to determine the number of periodontal sites with periodontal pathogens. Results: CIMT value was significantly higher in subjects with periodontitis than those without it (0.775 ± 0.268 and 0.683 ± 0.131 mm respectively, p = 0.027). C-reactive protein, leukocyte count and percentage of sites with periodontal pathogens were also significantly higher in subjects with periodontitis. Regression analysis identified age, periodontitis, and smoking as independent predictors of CIMT. Conclusions: These results suggest that untreated periodontitis is associated with early atherosclerotic carotid lesions and higher levels of infl ammatory markers.

Néstor J, López; Adriana, Chamorro; Marcelo, Llancaqueo.

2011-06-01

259

Combination of Root Surface Modification with BMP-2 and Collagen Hydrogel Scaffold Implantation for Periodontal Healing in Beagle Dogs  

Science.gov (United States)

Objective : Biomodification of the root surface plays a major role in periodontal wound healing. Root surface modification with bone morphogenetic protein (BMP) stimulates bone and cementum-like tissue formation; however, severe ankylosis is simultaneously observed. Bio-safe collagen hydrogel scaffolds may therefore be useful for supplying periodontal ligament cells and preventing ankylosis. We examined the effects of BMP modification in conjunction with collagen hydrogel scaffold implantation on periodontal wound healing in dogs. Material and Methods: The collagen hydrogel scaffold was composed of type I collagen sponge and collagen hydrogel. One-wall infrabony defects (5 mm in depth, 3 mm in width) were surgically created in six beagle dogs. In the BMP/Col group, BMP-2 was applied to the root surface (loading dose; 1 µg/µl), and the defects were filled with collagen hydrogel scaffold. In the BMP or Col group, BMP-2 coating or scaffold implantation was performed. Histometric parameters were evaluated at 4 weeks after surgery. Results: Single use of BMP stimulated formation of alveolar bone and ankylosis. In contrast, the BMP/Col group frequently enhanced reconstruction of periodontal attachment including cementum-like tissue, periodontal ligament and alveolar bone. The amount of new periodontal ligament in the BMP/Col group was significantly greater when compared to all other groups. In addition, ankylosis was rarely observed in the BMP/Col group. Conclusion: The combination method using root surface modification with BMP and collagen hydrogel scaffold implantation facilitated the reestablishment of periodontal attachment. BMP-related ankylosis was suppressed by implantation of collagen hydrogel. PMID:25674172

Kato, Akihito; Miyaji, Hirofumi; Ishizuka, Ryosuke; Tokunaga, Keisuke; Inoue, Kana; Kosen, Yuta; Yokoyama, Hiroyuki; Sugaya, Tsutomu; Tanaka, Saori; Sakagami, Ryuji; Kawanami, Masamitsu

2015-01-01

260

Why is Periodontitis Painless?  

Directory of Open Access Journals (Sweden)

Full Text Available Periodontitis is an infectious disease resulting in an often-painless destruction of tooth supporting tissues (the periodontium and enhances the risk for various systemic diseases. Infection and inflammation of mucosal tissue may induce the production of neuropeptides. The biological effects of the neuropeptides substance P (SP, calcitonin gene-related peptide (CGRP, vasoactive intestinal polypeptide (VIP, and neuropeptide Y (NPY are summarized. This review focuses on the recent research highlighting the role of the nervous system in suppressing pain and inflammation suggesting that neuropeptides have a pivotal role in the complex cascade of chemical activity associated with periodontal inflammation.

Rajababu P

2011-07-01

261

Periodontal disease and systemic complications  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Periodontal diseases comprise a number of infectious and inflammatory conditions brought about by the interaction between supragingival and subgingival biofilms and the host inflammatory response. Periodontal diseases should be considered systemic conditions. This means that they are both modulated [...] by the body's systems and play a role as a risk factor for systemic derangements. The current evidence supports some of these interactions, such as smoking as a risk factor for periodontal disease and diabetes mellitus, as both influenced by and influencing inflammatory changes in the periodontal tissue. Other potential associations are still being researched, such as obesity, hormonal changes, cardiovascular disease, and adverse outcomes in pregnancy. These, and others, still require further investigation before the repercussions of periodontal disease can be fully elucidated. Nevertheless, at the present time, the treatment of periodontal diseases-and, most importantly, their prevention-enables adequate intervention as a means of ensuring periodontal health.

Rui Vicente, Oppermann; Patricia, Weidlich; Marta Liliana, Musskopf.

262

Periodontal disease and systemic complications  

Directory of Open Access Journals (Sweden)

Full Text Available Periodontal diseases comprise a number of infectious and inflammatory conditions brought about by the interaction between supragingival and subgingival biofilms and the host inflammatory response. Periodontal diseases should be considered systemic conditions. This means that they are both modulated by the body's systems and play a role as a risk factor for systemic derangements. The current evidence supports some of these interactions, such as smoking as a risk factor for periodontal disease and diabetes mellitus, as both influenced by and influencing inflammatory changes in the periodontal tissue. Other potential associations are still being researched, such as obesity, hormonal changes, cardiovascular disease, and adverse outcomes in pregnancy. These, and others, still require further investigation before the repercussions of periodontal disease can be fully elucidated. Nevertheless, at the present time, the treatment of periodontal diseases-and, most importantly, their prevention-enables adequate intervention as a means of ensuring periodontal health.

Rui Vicente Oppermann

2012-01-01

263

Estrogen deficiency reduces the expression of estrogen receptor-beta in Wistar rats’ periodontal tissues  

OpenAIRE

Objectives: To assess the effect of ovariectomy on the expression of estrogen receptor-beta (ER-ß) in periodontal ligament and alveolar bone. Methods: This animal study was conducted at King Fahad Research Center, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia from March to October 2012. Thirty 12-week-old female Wistar rats were divided into 2 groups (15 each): ovariectomized (OVX) and sham-operated. Levels of estrogen and progesteron...

Al-sherbini, Mossad M.; Al-zahrani, Mohammad S.; Alrefaie, Zienab A.; Amin, Hanan A.; Zawawi, Khalid H.

2014-01-01

264

Bioengineered anterior cruciate ligament  

Science.gov (United States)

The present invention provides a method for producing an anterior cruciate ligament ex vivo. The method comprises seeding pluripotent stem cells in a three dimensional matrix, anchoring the seeded matrix by attachment to two anchors, and culturing the cells within the matrix under conditions appropriate for cell growth and regeneration, while subjecting the matrix to one or more mechanical forces via movement of one or both of the attached anchors. Bone marrow stromal cells are preferably used as the pluripotent cells in the method. Suitable matrix materials are materials to which cells can adhere, such as a gel made from collagen type I. Suitable anchor materials are materials to which the matrix can attach, such as Goinopra coral and also demineralized bone. Optimally, the mechanical forces to which the matrix is subjected mimic mechanical stimuli experienced by an anterior cruciate ligament in vivo. This is accomplished by delivering the appropriate combination of tension, compression, torsion, and shear, to the matrix. The bioengineered ligament which is produced by this method is characterized by a cellular orientation and/or matrix crimp pattern in the direction of the applied mechanical forces, and also by the production of collagen type I, collagen type III, and fibronectin proteins along the axis of mechanical load produced by the mechanical forces. Optimally, the ligament produced has fiber bundles which are arranged into a helical organization. The method for producing an anterior cruciate ligament can be adapted to produce a wide range of tissue types ex vivo by adapting the anchor size and attachment sites to reflect the size of the specific type of tissue to be produced, and also adapting the specific combination of forces applied, to mimic the mechanical stimuli experienced in vivo by the specific type of tissue to be produced. The methods of the present invention can be further modified to incorporate other stimuli experienced in vivo by the particular developing tissue, some examples of the stimuli being chemical stimuli, and electro-magnetic stimuli. Some examples of tissue which can be produced include other ligaments in the body (hand, wrist, elbow, knee), tendon, cartilage, bone, muscle, and blood vessels.

Altman, Gregory (Inventor); Kaplan, David (Inventor); Vunjak-Novakovic, Gordana (Inventor); Martin, Ivan (Inventor)

2001-01-01

265

PULP dead or alive  

Directory of Open Access Journals (Sweden)

Full Text Available A pain response to hot, cold or an electric pulp tester indicates the vitality of only a tooth's pulpal sensory supply; the response does not give any idea about the state of the pulp. Although the sensitivity of these tests is high, when false-positive and falsenegative results occur, they may affect the treatment of the tooth. A tooth falsely diagnosed as nonvital with an electric pulp tester may undergo an unnecessary root canal, whereas one falsely diagnosed as vital may be left untreated, causing the necrotic tissue to destroy the supporting tissues (resorption. The vascular supply is more important to the determination of the health of the pulp than the sensory supply. Pulp death is caused by cessation of blood flow and may result in a necrotic pulp, even though the pulpal sensory supply may still be viable. The pulp can be healed only if the circulating blood flow is healthy. Although still under investigation, diagnostic devices that examine pulpal blood flow, such as the pulse oximeter and laser Doppler flowmetry, show promising results for the assessment of pulp vitality.

Pankaj Agarwal

2011-12-01

266

Laser Application in Periodontics  

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Full Text Available INTRODUCTION: The use of lasers for treatment has become a common phenomenon in the medical field. Currently, numerous laser systems are available for dental use. The use of lasers for periodontal treatment becomes more complicated because the periodontium consists of both hard and soft tissues.METHODS: Related articles were gathered and selected carefully and reviewed. Among the many lasers available, high power lasers such as Carbon Dioxide Laser (CO2,Neodymium-Doped Yttrium Aluminium Garnet (Nd:YAG and diode lasers can be used in periodontics. The use of these lasers is limited to gingivectomy, frenectomy and similar soft tissue procedures including the removal of melanin pigmentation of gingiva. Recently, Erbium: Yttrium Aluminium Garnet(Er:YAG and Erbium, Chromium doped Yttrium Scandium Gallium Garnet (Er,Cr:YSGG lasers are used for scaling, root debridement, cutting, shaving, contouring and resection of oral osseous tissues.RESULTS: In addition to their surgical applications, low-level lasers such as Er:YAG laser irradiation promotes osteoblast proliferation showing higher and favorable bone tissue regeneration. These findings suggest faster bone tissue healing following periodontal and peri-implant low level laser therapy.CONCLUSION: Advantages of laser treatment in periodontics are effective and efficient soft and hard tissue ablation with a greater hemostasis, bactericidal effect, minimal wound contraction, faster bone tissue healing, minimal collateral damages along with reduced use of local analgesia.

Farnaz Falaki

2012-03-01

267

Periodontics II: Course Proposal.  

Science.gov (United States)

A proposal is presented for Periodontics II, a course offered at the Community College of Philadelphia to give the dental hygiene/assisting student an understanding of the disease states of the periodontium and their treatment. A standardized course proposal cover form is given, followed by a statement of purpose for the course, a list of major…

Dordick, Bruce

268

Lasers in periodontal therapy.  

Science.gov (United States)

About 50 years ago, lasers started to be used in periodontal treatment following evidence that wounds produced in animals healed more quickly after being irradiated with low-intensity lasers. Increased production of growth factors, stimulated mainly by red and infrared lasers, may participate in this process by influencing the behavior of various types of cells. High-intensity lasers have been used as an alternative to nonsurgical periodontal therapy in root biomodification and to reduce dentin hypersensivity; low-intensity lasers are frequently employed to improve tissue repair in regenerative procedures and in antimicrobial photodynamic therapy. Despite the abundance of promising data on the advantages of their use, there is still controversy regarding the real benefits of lasers and antimicrobial photodynamic therapy in periodontal and peri-implant treatment. A huge variation in the parameters of laser application among studies makes comparisons very difficult. An overview of the current concepts and findings on lasers in periodontal therapy is presented with emphasis on data collected from Latin-American researchers. PMID:25494605

Passanezi, Euloir; Damante, Carla Andreotti; de Rezende, Maria L Rubo; Greghi, Sebastião L Aguiar

2015-02-01

269

Proteases in Periodontal Disease  

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Full Text Available Introduction: The caries and the periodontal disease (PD are the most frequent alterations in the oral cavity. The PD presents two stages: gengivitis and periodontitis. The destruction of collagenous fibers which encases the tooth onto the alveolar bone is characteristic of the pariodontitis. The inclusion loss caused by this pathology is due to the presence of bacteria and their products, besides the tissue destruction. This process is caused by excessive discharge of cells of the organism defence which reach the damaged area, and among these cells are neutrophils. These cells free lysosomal granule, where enzymes known as proteases (elastase, colagenasis and catepsin G are present. When excessively delivered, they cause extensive tissue destruction. The organism innate defence respond to this process activating anti-proteases, such as alfa-1-antitripsin e alfa-2-macrogoblulin, and, as consequence, the inflammatory process is subdued. Objective: Revision of the literature on periodontitis and its markers. In periodontitis, the balance between protease and anti-protese seems to be altered and lead to the appearance of these ones. There is an increase of prevalence of PD in the world population. In recent times, it has been associated to systemic conditions that lead to tissue destruction. Perhaps, the cause is based on an exacerbated tissue reaction, more than on the bacterial aggression. Conclusion: The predisposition of the organism is an important factor for the disease development. At reading different studies, it was observed that the discharged protease during the neutrophils degranulation process has internal, not bacterial, origin.

Ana Rita Sokolonski ANTON

2006-09-01

270

Posterior cruciate ligament of the knee (image)  

Science.gov (United States)

The posterior cruciate ligament (PCL) is a powerful ligament extending from the top-rear surface of the tibia to the bottom-front surface of the femur. The ligament prevents the knee joint from posterior instability.

271

Periodontal Bioengineering: A Discourse in Surface Topographies, Progenitor Cells and Molecular Profiles  

Science.gov (United States)

Stem/progenitor cells are a population of cells capable of providing replacement cells for a given differentiated cell type. We have applied progenitor cell-based technologies to generate novel tissue-engineered implants that use biomimetic strategies with the ultimate goal of achieving full regeneration of lost periodontal tissues. Mesenchymal periodontal tissues such as cementum, alveolar bone (AB), and periodontal ligament (PDL) are neural crest-derived entities that emerge from the dental follicle (DF) at the onset of tooth root formation. Using a systems biology approach we have identified key differences between these periodontal progenitors on the basis of global gene expression profiles, gene cohort expression levels, and epigenetic modifications, in addition to differences in cellular morphologies. On an epigenetic level, DF progenitors featured high levels of the euchromatin marker H3K4me3, whereas PDL cells, AB osteoblasts, and cementoblasts contained high levels of the transcriptional repressor H3K9me3. Secondly, we have tested the influence of natural extracellular hydroxyapatite matrices on periodontal progenitor differentiation. Dimension and structure of extracellular matrix surfaces have powerful influences on cell shape, adhesion, and gene expression. Here we show that natural tooth root topographies induce integrin-mediated extracellular matrix signaling cascades in tandem with cell elongation and polarization to generate physiological periodontium-like tissues. In this study we replanted surface topography instructed periodontal ligament progenitors (PDLPs) into rat alveolar bone sockets for 8 and 16 weeks, resulting in complete attachment of tooth roots to the surrounding alveolar bone with a periodontal ligament fiber apparatus closely matching physiological controls along the entire root surface. Displacement studies and biochemical analyses confirmed that progenitor-based engineered periodontal tissues were similar to control teeth and uniquely derived from pre-implantation green fluorescent protein (GFP)-labeled progenitors. Together, these studies illustrate the capacity of natural extracellular surface topographies to instruct PDLPs to fully regenerate complex cellular and structural morphologies of tissues once lost to disease. We suggest that our strategy could be used for the replantation of teeth lost due to trauma or as a novel approach for tooth replacement using tooth-shaped replicas.

Dangaria, Smit J.

2011-12-01

272

ALTERNATIVE PULPING PROCESS FOR PRODUCING DISSOLVING PULP FROM JUTE  

OpenAIRE

Dissolving pulps are the raw materials of cellulose derivatives and of many other cellulosic products. Jute is a very good source of cellulose and worthy of consideration for the production of dissolving pulp. In this investigation jute fiber, jute cuttings, and jute caddis were used as raw materials to prepare dissolving pulp by a formic acid process. A very high bleached pulp yield (49 to 59%) was obtained in this process. The ?-cellulose content was 93 to 98%, with a high pulp viscosity....

Sarwar Jahan, M.; Sabina Rawsan; Nasima Chowdhury, D. A.; Al-maruf, A.

2008-01-01

273

Condiciones sistémicas asociadas con periodontitis en la infancia y la adolescencia: Una revisión de las posibilidades diagnósticas / Systemic conditions associated with periodontitis in childhood and adolescence: A review of diagnostic possibilities  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish El término periodontitis se usa para describir un grupo de enfermedades multifactoriales que llevan a la destrucción progresiva de las estructuras que unen los dientes a los maxilares, el llamado aparato de soporte, que incluye el ligamento periodontal, cemento radicular y hueso alveolar. Si permane [...] ce sin tratamiento, este proceso conlleva en última instancia a la pérdida dentaria. La patogenia de estas enfermedades implica inicialmente la colonización del microambiente gingival de un huésped susceptible por una bacteria procedente de la placa dental. Posteriormente, la mayoría de la destrucción tisular característica de la periodontitis es una respuesta del huésped contra estos organismos. Uno de los factores principales que parecen modular la severidad de esta enfermedad es la salud general. Por lo tanto, la periodontitis severa en individuos jóvenes puede ser una manifestación de una enfermedad sistémica subyacente. En esta revisión discutiremos las enfermedades sistémicas más importantes que podrían ser consideradas en el diagnóstico diferencial al explorar a un paciente pediátrico con periodontitis. Abstract in english The term periodontitis is used to describe a group of multifactorial diseases that result in the progressive destruction of the structures that support the teeth within the jaws, the so-called attachment apparatus, which includes the periodontal ligament, cementum and alveolar bone. If left untreate [...] d, this process can ultimately lead to tooth loss. The pathogenesis of these diseases involves the initial colonization of the gingival microenvironment of a susceptible host by pathogenic bacteria found in dental plaque. Subsequently, much of the tissue destruction characteristic of periodontitis is a "by-product" of the host response directed against these organisms. One of the major factors that appear to modulate disease severity is systemic health. Severe periodontitis in young individuals can therefore be a manifestation of an underlying systemic disease. In this review we will discuss the most important systemic diseases that should be considered in a differential diagnosis when evaluating a pediatric patient presenting with periodontitis.

Thomas P., Sollecito; Kathleen E., Sullivan; Andres, Pinto; Jeffrey, Stewart; Jonathan, Korostoff.

2005-04-01

274

Effects of periodontal afferent inputs on corticomotor excitability in humans  

DEFF Research Database (Denmark)

The aim of the present study was to determine in humans whether local anaesthesia (LA) or nociceptive stimulation of the periodontal ligaments affects the excitability of the face primary motor cortex (MI) related to the tongue and jaw muscles, as measured by transcranial magnetic stimulation (TMS). Twelve healthy volunteers (11 men, 1 woman, 25.3 +/- 4.2 years) participated in two 3-h sessions separated by 7 days. The LA carbocain or the nociceptive irritant capsaicin was randomly injected into the periodontal ligament of the lower right central incisor. In both sessions, TMS-motor evoked potential (MEP) stimulus-response curves and corticomotor maps were acquired for the tongue and masseter muscles before (baseline) and at 5, 30 and 60 min post-application of carbocain or capsaicin. Transcranial magnetic stimulation-MEP stimulus-response curves were also acquired at these time points for the first dorsal interosseous (FDI) as an internal control. Burning pain intensity and mechanical sensitivity ratings to a von Frey filament applied to the application site were recorded on an electronic visual analogue scale (VAS). All subjects reported a decreased mechanical sensitivity (anova: P = 0.004) in the LA session and a burning pain sensation (VAS peak pain: 6.4 +/- 1.0) in the capsaicin session. No significant changes in cortical excitability of the MI, as reflected by TMS-MEP stimulus-response curves or corticomotor maps for the tongue, masseter or FDI were found between baseline and post-injection for the LA (anovas: P > 0.22) or capsaicin (anovas: P > 0.16) sessions. These findings suggest that a transient loss or perturbation in periodontal afferent input to the brain from a single incisor is insufficient to cause changes in corticomotor excitability of the face MI, as measured by TMS in humans.

Zhang, Yang; Boudreau, Shellie

2010-01-01

275

[Metacarpal index in periodontal disease].  

Science.gov (United States)

The hypothesis that there is a relationship between total bone mass reduction and alveolar bone loss in periodontal disease was studied in a group of 98 hospitalized patients free of metabolic disease. All patients had periodontitis with marked evidence of alveolar bone loss. A significant correlation of alveolar bone resorption to the total bone mass reduction in patients with periodontal disease was found. PMID:2636494

Tesseromatis, C; Myrkou, A; Dalles, C; Speggos, M

1989-07-01

276

Periodontal disease and systemic complications  

OpenAIRE

Periodontal diseases comprise a number of infectious and inflammatory conditions brought about by the interaction between supragingival and subgingival biofilms and the host inflammatory response. Periodontal diseases should be considered systemic conditions. This means that they are both modulated by the body's systems and play a role as a risk factor for systemic derangements. The current evidence supports some of these interactions, such as smoking as a risk factor for periodontal disease ...

Rui Vicente Oppermann; Patricia Weidlich; Marta Liliana Musskopf

2012-01-01

277

EFICACIA DEL MOXIFLOXACINO EN PERIODONTITIS / Efficacy of Moxifloxacin on periodontitis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Un grupo de bacterias predominantemente Gram.-negativas anaerobias están asociadas con el inicio y progreso de la enfermedad periodontal. Porphyromonas Gingivalis, Aggregatibacter Actinomycetemcomitans y Tannerella forsythensis son los microorganismos fuertemente implicados como agentes etiológicos [...] de la periodontitis. El propósito principal del tratamiento periodontal es reducir la infección, resolver la inflamación y prevenir un deterioro posterior. La terapia antibiótica adjunta puede usarse para mejorar los resultados del tratamiento en pacientes con periodontitis crónica avanzada y periodontitis agresiva. Es muy extenso el rango de antibióticos empleados para tratar las infecciones periodontales: tetraciclinas, metronidazol solo o combinado con amoxicilina, azitromicina, clindamicina etcétera. La presencia de resistencias bacterianas sugiere alternativas como el moxifloxacino, el cual ha mostrado efectividad contra Gram.-positivos, anaerobios, microor-ganismos plantónicos, y bacterias localizadas en biopelículas e intracelularmente. Abstract in english A group of predominantly gram-negative , anaerobic bacterias are associated with initiation and progression of periodontal disease. Microorganism strongly implicated as etiologic agents of periodontitis include Porphyromonas Gingivalis, Aggregatibacter Actinomycetemcomitans and Tannerella forsythens [...] is. The primary aim of periodontal treatment is to reduce the infection, resolve inflammation and prevent any further destruction. Antibiotics adjunctive can be used to improve treatment outcomes in patients with severe chronic periodontitis and aggressive periodontitis. The range of antibiotics used to treat periodontal infections is quite extensive including the tetracyclines, metronidazole and the combination with amoxicillin, azythromicin, clindamycin etc. Problems of bacterial resistance suggest alternatives as moxifloxacin that showed activity against gram-positives, anaerobes, planktonic microorganism as well as bacteria located within a biofilm or intracellularly.

Carlos Martín, Ardila Medina; Isabel Cristina, Guzmán Zuluaga; María Patricia, Arbeláez Montoya.

2009-09-01

278

EFICACIA DEL MOXIFLOXACINO EN PERIODONTITIS Efficacy of Moxifloxacin on periodontitis  

Directory of Open Access Journals (Sweden)

Full Text Available Un grupo de bacterias predominantemente Gram.-negativas anaerobias están asociadas con el inicio y progreso de la enfermedad periodontal. Porphyromonas Gingivalis, Aggregatibacter Actinomycetemcomitans y Tannerella forsythensis son los microorganismos fuertemente implicados como agentes etiológicos de la periodontitis. El propósito principal del tratamiento periodontal es reducir la infección, resolver la inflamación y prevenir un deterioro posterior. La terapia antibiótica adjunta puede usarse para mejorar los resultados del tratamiento en pacientes con periodontitis crónica avanzada y periodontitis agresiva. Es muy extenso el rango de antibióticos empleados para tratar las infecciones periodontales: tetraciclinas, metronidazol solo o combinado con amoxicilina, azitromicina, clindamicina etcétera. La presencia de resistencias bacterianas sugiere alternativas como el moxifloxacino, el cual ha mostrado efectividad contra Gram.-positivos, anaerobios, microor-ganismos plantónicos, y bacterias localizadas en biopelículas e intracelularmente.A group of predominantly gram-negative , anaerobic bacterias are associated with initiation and progression of periodontal disease. Microorganism strongly implicated as etiologic agents of periodontitis include Porphyromonas Gingivalis, Aggregatibacter Actinomycetemcomitans and Tannerella forsythensis. The primary aim of periodontal treatment is to reduce the infection, resolve inflammation and prevent any further destruction. Antibiotics adjunctive can be used to improve treatment outcomes in patients with severe chronic periodontitis and aggressive periodontitis. The range of antibiotics used to treat periodontal infections is quite extensive including the tetracyclines, metronidazole and the combination with amoxicillin, azythromicin, clindamycin etc. Problems of bacterial resistance suggest alternatives as moxifloxacin that showed activity against gram-positives, anaerobes, planktonic microorganism as well as bacteria located within a biofilm or intracellularly.

Carlos Martín Ardila Medina

2009-09-01

279

Experimental chronic periodontitis morphogenesis  

Directory of Open Access Journals (Sweden)

Full Text Available Morphogenesis of periodontium tissue in a model of chronic periodontitis was studied. Adult Wistar rats wereused in a model; chronic periodontitis was developed through mastication-related loading decrease. Histological assessmentof periodontium tissue was conducted at Days 7, 14, 21 and 30. It was demonstrated that dystrophic tissue changes prevailover the inflammatory one in this particular experimental model. The structural elements of periodontium were involved intothe pathologic process in the following sequence: gingival mucosa connective tissue – Day 7, gingival epithelium – Day 14;periodontium of the tooth-gingival connection area – Day 21; bone tissue of the alveolar process of the jaw – Days 21-30.Inflammation was manifested at Day 30, only in areas of tooth-gingival connection.

Schneider S.A.

2011-01-01

280

Diabetes and periodontal disease  

OpenAIRE

Diabetes mellitus is a systemic disease characterized by increased blood glucose levels and abnormalities of lipid metabolism due to absence or decreased level of insulin. It affects all the body organs and their functions either directly or indirectly. Every dentist should have a basic understanding of the etiopathogenesis, oral and systemic manifestations of this disease. The periodontal diseases are a consequence of extension of the gingival inflammation into the underlying supporting stru...

Daniel, Rajkumar; Gokulanathan, Subramanium; Shanmugasundaram, Natarajan; Lakshmigandhan, Mahalingam; Kavin, Thangavelu

2012-01-01

281

Dental pulp stem cells: Potential significance in regenerative medicine  

Directory of Open Access Journals (Sweden)

Full Text Available To date, three types of dental stem cells have been isolated: Dental Pulp Stem Cells (DPSC, Stem Cells From Human Exfoliated Deciduous Teeth (SHED and Immature Dental Pulp Stem Cells (IDPC. These dental stem cells are considered as mesenchymal stem cells. They reside within the perivascular niche of dental pulp. They are highly proliferative, clonogenic, multipotent and are similar to mesenchymal Bone Marrow Stem Cells (BMSC. Also, they have high plasticity and can be easy isolated. The expressions of the alkaline phosphatase gene, dentin matrix protein 1 and dentinsialophosphoprotein are verified in these cells. Analyses of gene expression patterns indicated several genes which encode extracellular matrix components, cell adhesion molecules, growth factors and transcription regulators, cell signaling, cell communication or cell metabolism. In both conditions, in vivo and in vitro, these cells have the ability to differentiate into odontoblasts, chondrocytes, osteoblasts, adipocytes, neurons, melanocytes, smooth and skeletal muscles and endothelial cells. In vivo, after implantation, they have shown potential to differentiate into dentin but also into tissues like bone, adipose or neural tissue. In general, DPSCs are considered to have antiinflammatory and immunomodulatory abilities. After being grafted into allogenic tissues these cells are ableto induce immunological tolerance. Immunosuppressive effect is shown through the ability to inhibit proliferation of T lymphocytes. Dental pulp stem cells open new perspectives in therapeutic use not only in dentin regeneration, periodontal tissues and skeletoarticular, tissues of craniofacial region but also in treatment of neurotrauma, autoimmune diseases, myocardial infarction, muscular dystrophy and connective tissue damages.

Todorovi? Vera

2008-01-01

282

Ultrastructure and histochemistry of the dental cuticle in adult periodontitis.  

Science.gov (United States)

This study examined the dental cuticle (DC) at the interface with cementum surface, as well as its relationship to the overlying subgingival plaque (SP), the so-called plaque-free zone (PFZ), the junctional epithelium (JE), and the coronal fibers of the residual periodontal ligament (PL) by transmission electron microscopy (TEM) and histochemistry. Material comprised of 41 extracted, adult periodontitis-affected teeth (AP). Following extraction, 20 teeth were fixed in 3% glutaraldehyde in 0.1M sodium cacodylate, post-fixed in 1% osmium tetroxide, embedded in araldite, decalcified in EDTA, re-embedded in araldite, and sectioned. En bloc histochemistry was undertaken on the remaining 21 teeth, using ruthenium red, alcian blue-lanthanum nitrate, or safranin-O, and processed as above. Results show that the DC covered the cementum surface from the SP to the JE, and formed an interface with these structures. No DC was observed at the interface with PL. Morphological variations in DC surface were observed at the interface with the SP and at the so-called PFZ where bacteria were always in close contact with or surrounded by the DC. At the interface with JE, the DC appeared homogeneous, although layers varying in electron density were distinguishable. Teeth treated histochemically revealed a positive reaction of DC and bacteria to the three methods, suggesting the presence of anionic polymers including glycoproteins in the DC. It was concluded that on adult periodontitis affected teeth, the DC always covers exposed cementum and may mediate bacterial adhesion, and adsorb components from the periodontal pocket. PMID:8336252

Friedman, M T; Barber, P; Newman, H N

1993-06-01

283

Periodontal disease: a genetic perspective  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Periodontitis is a multifactorial disease that causes tooth loss. The complex pathogenesis of periodontitis implies the involvement of a susceptible host and a bacterial challenge. Many studies have provided a valuable contribution to understanding the genetic basis of periodontal disease, but the s [...] pecific candidate genes of susceptibility are still unknown. In fact, genome-wide studies and screening of single-nucleotide polymorphisms have yielded new genetic information without a definitive solution for the management of periodontal disease. In this manuscript, we provide an overview of the most relevant literature, presenting the main concepts and insights of the strategies that have been emerging to better diagnose and treat periodontal disease based on biomarker analysis and host modulation.

Mario, Taba Jr; Sergio Luis Scombatti de, Souza; Viviane Casagrande, Mariguela.

284

Adult Stem Cell Therapy for Periodontal Disease  

Science.gov (United States)

Periodontal disease is a major cause of tooth loss and characterized by inflammation of tooth-supporting structures. Recently, the association between periodontal disease and other health problems has been reported, the importance of treating periodontal disease for general health is more emphasized. The ultimate goal of periodontal therapy is regeneration of damaged periodontal tissues. The development of adult stem cell research enables to improve the cell-based tissue engineering for periodontal regeneration. In this review, we present the results of experimental pre-clinical studies and a brief overview of the current state of stem cells therapy for periodontal diseases. PMID:24855536

Kim, Su-Hwan; Seo, Byoung-Moo; Choung, Pill-Hoon; Lee, Yong-Moo

2010-01-01

285

Periodontal tissue engineering: defining the triad.  

Science.gov (United States)

The idea that somatic stem cells are localized in periodontal ligament (PDL) tissues as PDL stem cells (PDLSCs) responsible for construction and reconstruction of the periodontium has been widely accepted. Many dental scientists have attempted to clarify the identity of these PDLSCs, but the number of PDLSCs localized in PDL tissues is too small to be routinely and conveniently analyzed. Therefore, researchers have been attempting to develop undifferentiated PDL cell lines by transducing them with genes that are suitable for immortalization. The present authors were the first to succeed in establishing two clonal human PDL stem/progenitor cell lines that possessed multipotency derived from PDL tissues and that expressed PDL-related molecules as well as neural crest- and embryonic stem-related markers. The differentiation stages of these cell lines appeared to vary based on their potential to differentiate into other lineage cells, their response to tissue regeneration-related cytokines, and their behavior when transplanted into immunodeficient rats. This review describes the phenotypes of these cell lines compared with reported PDLSCs or other MSCs and discusses contemporary circumstances related to PDL regenerative medicine. Differential analyses between these two clones will reveal the mechanism of differentiation of PDLSCs as well as their phenotypes. The results will also allow for the acquisition of a mass population of PDLSCs or other stem cells directed toward PDL-lineage cells and to develop an unmet treatment needed for construction and reconstruction of PDL tissues based on tissue engineering techniques. PMID:24278956

Maeda, Hidefumi; Fujii, Shinsuke; Tomokiyo, Atsushi; Wada, Naohisa; Akamine, Akifumi

2013-01-01

286

Platelet Rich Fibrin in the revitalization of tooth with necrotic pulp and open apex  

OpenAIRE

Regeneration of pulp-dentin complex in an infected necrotic tooth with an open apex is possible if the canal is effectively disinfected. The purpose of this case report is to add a regenerative endodontic case to the existing literature about using Platelet Rich Fibrin (PRF). A nine year old boy who accidently broke his immature maxillary central incisor tooth, developed pulpal necrosis with apical periodontitis. After the access cavity preparation, the canal was effectively irrigated with 20...

Shivashankar, Vasundara Yayathi; Johns, Dexton Antony; Vidyanath, S.; Kumar, M. Ramesh

2012-01-01

287

THE RELATIONSHIP BETWEEN PERIODONTAL DISEASE (PD AND CARDIOVASCULAR DISEASE (CVD.  

Directory of Open Access Journals (Sweden)

Full Text Available

The recent focus on the potential link between periodontal and cardiovascular disease (PD and CVD  is part of the larger renewed interest on the role of infection and inflammation in the etiology of atherosclerosis and its clinical manifestations.  Periodontal Disease is an inflammatory process affecting the periodontium, the tissue that surrounds and supports the teeth . The process usually starts with an inflammatory process of the gum (gingivitis but it may progress with an extensive involvement of the gum, as well as the periodontal ligament and the bone surrounding the teeth resulting in substantial bone loss. Periodontal disease is a common oral pathological condition in the adult age and represents the leading cause of tooth loss. PD prevalence increases with age and there are estimates that up to 49,000,000 Americans may suffer from some form of gum disease. The gingival plaque associated with PD is colonized by a number of gram-positive and gram-negative bacteria that have been shown to affect the initiation and development of PD and have been associated with the potential etiological role of PD in CVD and other chronic conditions. A potential etiological link between PD and CVD may have important public health implications as both the exposure (PD and the outcomes (CVD are highly prevalent in industrialized societies. In situations in which both the exposure and the outcome are highly prevalent even modest associations, like those observed in the studies reporting on the link between PD and CVD outcomes, may have relevance. There are  not  definite data on the effect of periodontal treatment on CVD clinical outcomes (either in primary or secondary prevention however it should be pointed out that the limited (both in terms of numbers and study design experimental evidence in humans suggests a possible beneficial effect of periodontal treatment of indices of functional and structural vascular health.

Maurizio Trevisan

2010-08-01

288

Lipoproteins and lipoprotein metabolism in periodontal disease  

OpenAIRE

A growing body of evidence indicates that the incidence of atherosclerosis is increased in subjects with periodontitis – a chronic infection of the oral cavity. This article summarizes the evidence that suggests periodontitis shifts the lipoprotein profile to be more proatherogenic. LDL-C is elevated in periodontitis and most studies indicate that triglyceride levels are also increased. By contrast, antiatherogenic HDL tends to be low in periodontitis. Periodontal therapy tends to shift lip...

Griffiths, Rachel; Barbour, Suzanne

2010-01-01

289

Adult Stem Cell Therapy for Periodontal Disease  

OpenAIRE

Periodontal disease is a major cause of tooth loss and characterized by inflammation of tooth-supporting structures. Recently, the association between periodontal disease and other health problems has been reported, the importance of treating periodontal disease for general health is more emphasized. The ultimate goal of periodontal therapy is regeneration of damaged periodontal tissues. The development of adult stem cell research enables to improve the cell-based tissue engineering for perio...

Kim, Su-hwan; Seo, Byoung-moo; Choung, Pill-hoon; Lee, Yong-moo

2010-01-01

290

Anterior cruciate ligament reconstruction  

International Nuclear Information System (INIS)

This paper determines the efficacy of MR imaging in evaluation of the anterior cruciate ligament (ACL) following reconstructive surgery. Forty-three MR examinations were performed in 33 patients who had undergone previous arthroscopic ACL reconstruction with patellar bone-tendon- bone autografts (postoperative period, 1-24 months; mean, 5.2 months). Of the 40 studies performed in clinically stable knees (30 patients), MR demonstrated a well-defined, signal void ACL graft in 36. Of the three studies performed in three patients with clinical ACL laxity or suspected tear, the neoligament was of intermediate definition in one and nondiscernible in the other two. As in the native knee, buckling of the PCL was suggestive of ACL insufficiency. Bone tunnel placement, patellar tendon changes, and joint effusions were also evaluated

291

Demonstrating the fibular collateral ligament.  

OpenAIRE

A posture is described which allows palpation of the fibular collateral ligament of the knee as an isolated structure. Visual identification is also possible. This is of interest to the clinician and student of surface anatomy.

Pridmore, S. A.

1980-01-01

292

Clinical features of early periodontitis  

DEFF Research Database (Denmark)

BACKGROUND: Most of the evidence on periodontitis in young individuals originates in case series or case-control studies of poor quality. We investigated the intraoral distribution of clinical attachment level (CAL) and probing depth (PD) and the associations between the oral hygiene parameters and the signs of periodontitis (CAL and PD) in adolescents. METHODS: This study consisted of 87 cases presenting with CAL > or =3 mm in at least two of the 16 teeth recorded and 73 non-cases who did not fulfill this inclusion criterion, nested in a fully enumerated adolescent population, who were screened for signs of periodontitis. The 160 subjects were reexamined by a single trained and calibrated periodontist. The intraoral patterns of periodontal destruction were described graphically. RESULTS: Cases had more supragingival plaque, more supragingival calculus, and more bleeding on probing than non-cases. The intraoral patterns of periodontal destruction were similar in cases and non-cases. The site-specific associations between the putative determinants supragingival plaque, supragingival calculus, and bleeding on probing and the signs of periodontal destruction were highly positive. CONCLUSION: The results of this study lend little support to the notion that a particular intraoral pattern of breakdown is specific to young cases of severe periodontitis, nor do the results support the view that destruction is incommensurate with oral hygiene parameters.

López, Rodrigo; Frydenberg, Morten

2009-01-01

293

EFFECT OF SCREW EXTRUSION PRETREATMENT ON PULPS FROM CHEMICAL PULPING  

Directory of Open Access Journals (Sweden)

Full Text Available The effect of compressive pretreatment before chemical pulping on the properties of poplar kraft and soda-AQ pulp was evaluated. Compressive pretreatment not only resulted in the dissolution of hemicellulose, but also leached extractives. Pulps made from compressive pretreated wood chips required lower beating energy than the untreated pulps to achieve the same beating degree of 45°SR, and the brightness of the handsheets was improved by 2% ISO. Compressive pretreatment allowed for efficient delignification and saved about 6% alkali consumption to achieve similar pulp screen yield. Furthermore, a higher content of fines and slightly lower mechanical properties were observed after the compressive treatment.

Cuihua Dong,

2012-07-01

294

Diabetes mellitus and periodontal disease  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction. This review highlights the relations between diabetes mellitus and periodontal disease, as well as the pathogenic mechanisms which are still the subject of investigations. The possible pathogenic mechanisms important for developing periodontal disease in the diabetics are: vascular gingival changes, the disorders in the metabolism of the collagen, disorders in the function of the polimorphonuclear leukocytes and specific microbial flora in the parodontal pockets. Conclusion. It is clear that adequate early recognition and good treatment are very important and significant for treatment of diabetic periodontal disease.

Kesi? Ljiljana

2009-01-01

295

Doença periodontal e diabete melito tipo 2  

Directory of Open Access Journals (Sweden)

Full Text Available Introdução: a doença periodontal é considerada a sexta complicação clássica do diabete melito. Estudos recentes relatam que o diabete melito e a doença periodontal apresentam uma associação bidirecional, na qual o diabete favorece o desenvolvimento da doença periodontal e esta, quando não tratada, dificulta o controle metabólico do diabete. As periodontites relacionadas a doenças sistêmicas são causadas pela placa bacteriana e também exacerbadas pela condição oral. Objetivo: realizar uma revisão de literatura em relação à influência da doença periodontal no fator sistêmico do paciente diabético, e por sua vez, a influência do diabete no desenvolvimento e progressão da doença periodontal. Conclusão: o diabete melito é um fator de importância na incidência e prevalência da doença periodontal, assim como a doença periodontal pode ter influência sobre o controle metabólico do diabete. O tratamento periodontal parece contribuir para a melhoria do controle glicêmico de indivíduos diabéticos e com doença periodontal.

Georgia Verardi

2009-01-01

296

Inquiry Teaching in Clinical Periodontics.  

Science.gov (United States)

An adaptation of the inquiry method of teaching, which develops skills of information retrieval and reasoning through systematic questioning by the teacher, is proposed for instruction in clinical periodontics. (MSE)

Heins, Paul J.; Mackenzie, Richard S.

1987-01-01

297

Periodontal disease and diabetes mellitus  

OpenAIRE

Periodontal disease (PD) is one of the most commonly known human chronic disorders. The relationship between PD and several systemic diseases such as diabetes mellitus (DM) has been increasingly recognized over the past decades.

Negrato, Carlos Antonio; Tarzia, Olinda; Jovanovic?, Lois; Chinellato, Luiz Eduardo Montenegro

2013-01-01

298

Potential Role of Dentin Sialoprotein by Inducing Dental Pulp Mesenchymal Stem Cell Differentiation and Mineralization for Dental Tissue Repair  

OpenAIRE

Introduction: Dentin sialoprotein (DSP) is a dentin extracellular matrix protein, a unique marker of dentinogenesis and plays a vital role in odontoblast differentiation and dentin mineralization. Recently, studies have shown that DSP induces differentiation and mineralization of periodontal ligament stem cells and dental papilla mesenchymal cells in vitro and rescues dentin deficiency and increases enamel mineralization in animal models.The hypothesis: DSP as a nature therapeutic agent stimu...

Zhi Chen; Shuo Chen; Li-An Wu; Guo-Hua Yuan; Guo-Bin Yang

2010-01-01

299

Health Literacy in Periodontal Patients  

OpenAIRE

Introduction: health literacy is a fundamental part of the healing promotion. The aim of this study was to evaluate periodontal health literacy among patients. Materials and methods: 296 patients attending periodontal clinic who were above 16 years old participated in this study. Gathering data was based on screening questions on a 5-point Likert scale. After completion questionnaire, data was analyzed by Mann-Whitney and Kruskal-Wallis test. Based on the scores of questions, patients were cl...

Ahmad Haerian; Ali Moemen; Saeede Asgari; Farzane Vaziri

2013-01-01

300

Diabetes mellitus and periodontal disease  

OpenAIRE

Introduction. This review highlights the relations between diabetes mellitus and periodontal disease, as well as the pathogenic mechanisms which are still the subject of investigations. The possible pathogenic mechanisms important for developing periodontal disease in the diabetics are: vascular gingival changes, the disorders in the metabolism of the collagen, disorders in the function of the polimorphonuclear leukocytes and specific microbial flora in the parodontal pockets. Conclusion. It ...

Kesi? Ljiljana; Petrovi? Dragan; Obradovi? Radmila; Gaši? Jovanka; Todorovi? Kosta

2009-01-01

301

Doença Periodontal e diabetes Mellitus  

OpenAIRE

O objectivo deste trabalho foi avaliar, através da literatura, as possíveis associações entre diabetes e doença periodontal. A expressão “doença periodontal” é usada para designar, um conjunto de manifestações patológicas que afectam as estruturas de suporte dos dentes e caracteriza-se clinicamente por sintomas e sinais como inflamação, bolsas de profundidade variável à sondagem, perda de inserção, recessão gengival e mobilidade dentária. Estudos epidemiológicos permit...

José António Lobo Pereira

2007-01-01

302

Posterior cruciate ligament (PCL) injury - aftercare  

Science.gov (United States)

... of tissue that connects bone to bone. The posterior cruciate ligament (PCL) is located inside your knee joint and ... Curtis C, Bienkowski P, Micheli LJ. Posterior cruciate ligament ... Medicine and Rehabilitation. 2nd ed. St. Louis, MO: Saunders ...

303

Scaffold-free cell pellet transplantations can be applied to periodontal regeneration.  

Science.gov (United States)

Cell transplantation has emerged as a novel therapeutic strategy for periodontitis, and the adoption of cell pellet offers advantages by secreting abundant extracellular matrix (ECM) and eliminating the adverse effect of cell carriers. This study aimed to fabricate scaffold-free periodontal ligament stem cell (PDLSC) pellets (MUCPs) and to evaluate their regeneration potential. We constructed monolayer cell pellets (MCPs) by fabricating and culturing multilayered cell sheets (MUCS) and constructed MUCPs from the MUCS. Immunochemistry, scanning electron microscope, real-time PCR, and Western blot analysis showed higher levels of COL-I, COL-III, fibronectin, and laminin in the MUCPs. Furthermore, the massive increase in ECM secretion improved cell adhesion, migration, and proliferation. Finally, upon transplantation into the omentum sac and periodontal defects, all the transplants formed regular aligned cementum/PDL-like complex, but the mineral deposit and fiber alignment were more obvious in the MUCPs than in the MCPs. Altogether, our results suggest that MUCPs may be a promising alternative to periodontal repair for future clinical application. PMID:23363564

Guo, Weihua; He, Yong; Tang, Xuepeng; Chen, Gang; Shi, Haigang; Gong, Kun; Zhou, Jing; Wen, Lingying; Jin, Yan

2014-02-01

304

Dental pulp tissue engineering  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese A polpa dental é um tecido conjuntivo altamente especializado que possui uma restrita capacidade de regeneração, devido à sua disposição anatômica e à natureza pós-mitótica das células odontoblásticas. A remoção total da polpa, seguida da desinfecção do canal radicular e seu preenchimento com materi [...] al artificial proporciona a perda de uma significante quantidade de dentina deixando como sequela um dente não vital e enfraquecido. Entretanto, a endodontia regenerativa é um campo emergente da engenharia tecidual, que demonstrou resultados promissores utilizando células-tronco associadas à scaffolds e moléculas bioativas. Desta forma, esse artigo revisa os recentes avanços obtidos na regeneração do tecido pulpar baseado nos princípios da engenharia tecidual e fornece aos leitores informações compreensivas sobre os diferentes aspectos envolvidos na engenharia tecidual. Assim, nós especulamos que a combinação ideal de células, scaffolds e moléculas bioativas pode resultar em significantes avanços em outras áreas da pesquisa odontológica. Os dados levantados em nossa revisão demonstraram que estamos em um estágio no qual, o desenvolvimento de tecidos complexos, tais como a polpa dental, não é mais inatingível e que a próxima década será um período extremamente interessante para a pesquisa odontológica. Abstract in english Dental pulp is a highly specialized mesenchymal tissue that has a limited 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 has demonstrated promising results using stem cells associated with scaffolds and responsive molecules. Thereby, this article reviews the most recent endeavors to regenerate pulp tissue based on tissue engineering principles and provides insightful information to readers about the different aspects involved 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 findings collected in this literature review show that we are now at a stage in which engineering a complex tissue, such as the dental pulp, is no longer an unachievable goal and the next decade will certainly be an exciting time for dental and craniofacial research.

Flávio Fernando, Demarco; Marcus Cristian Muniz, Conde; Bruno Neves, Cavalcanti; Luciano, Casagrande; Vivien Thiemy, Sakai; Jacques Eduardo, Nör.

305

Bisphosphonates in periodontal treatment: a review.  

Science.gov (United States)

Periodontitis is a multifactorial disease involving bacterial biofilms and the generation of an inflammatory response. The latter causes the major part of the periodontal tissue breakdown. Alveolar bone resorption is a major component of the periodontal destruction observed in periodontitis. Novel treatment modalities of periodontitis intend to control and modulate the host response to bacterial aggression. Drugs such as bisphosphonates (BPs) are proven antiresorptive agents that can potentially inhibit the alveolar bone resorption. This review describes the potential use of BPs in periodontal treatment and could be said that BPs have an in vitro and in vivo capability of reducing bone resorption. Only a few studies have been carried out on the improvement of clinical periodontal parameters after the administration of BPs. Therefore, the published data are not sufficient to establish an evidence-based relevance for the use of these drugs in the treatment of periodontal diseases. PMID:19408809

Badran, Zahi; Kraehenmann, Michael Alexander; Guicheux, Jérôme; Soueidan, Assem

2009-01-01

306

Emdogain: Últimos avances en regeneración periodontal / Emdogain: An update in periodontal regeneration  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish Emdogain es un compuesto de proteínas derivadas de la matriz del esmalte, capaz de inducir la regeneración verdadera del aparato de inserción. Como principal indicación destaca el tratamiento de defectos infraóseos, ganancia de hueso y reducción de la profundidad de sondaje con mínima recesión gingi [...] val. Es un procedimiento técnicamente simple, con poco riesgo y menos invasivo que las técnicas de regeneración convencionales. La cuidada selección del paciente, el empleo de una técnica adecuada así como el riguroso control postoperatorio son factores importantes para el éxito del tratamiento. Abstract in english Emdogain is a compound of proteins derived from the enamel matrix which are a crucial factor in initiating the formation of acellular root cementum and stimulate the development of the periodontal ligament and alveolar bone. The main indication for the application of EMD is the intrabony defects tre [...] atment with significant clinical attachment level gains, probing depht reductions and minimal gingival recession. The application of EMD is a simple procedure with less risk than other techniques and less invasive than conventional guided tissue regeneration. The carefully selection of the patient, the use of an adecuate technique and the strict postoperatory control are very important factors on the treatment success.

X., Pousa; C., Rodríguez; F., Pastor; D., Rodrigo.

2005-04-01

307

Emdogain: Últimos avances en regeneración periodontal Emdogain: An update in periodontal regeneration  

Directory of Open Access Journals (Sweden)

Full Text Available Emdogain es un compuesto de proteínas derivadas de la matriz del esmalte, capaz de inducir la regeneración verdadera del aparato de inserción. Como principal indicación destaca el tratamiento de defectos infraóseos, ganancia de hueso y reducción de la profundidad de sondaje con mínima recesión gingival. Es un procedimiento técnicamente simple, con poco riesgo y menos invasivo que las técnicas de regeneración convencionales. La cuidada selección del paciente, el empleo de una técnica adecuada así como el riguroso control postoperatorio son factores importantes para el éxito del tratamiento.Emdogain is a compound of proteins derived from the enamel matrix which are a crucial factor in initiating the formation of acellular root cementum and stimulate the development of the periodontal ligament and alveolar bone. The main indication for the application of EMD is the intrabony defects treatment with significant clinical attachment level gains, probing depht reductions and minimal gingival recession. The application of EMD is a simple procedure with less risk than other techniques and less invasive than conventional guided tissue regeneration. The carefully selection of the patient, the use of an adecuate technique and the strict postoperatory control are very important factors on the treatment success.

X. Pousa

2005-04-01

308

Effect of khat chewing on periodontal pathogens in subgingival biofilm from chronic periodontitis patients  

OpenAIRE

Aims: Existing in vitro and in vivo data suggest that khat may have a favorable effect on periodontal microbiota. The purpose of this study was to assess the effect of khat chewing on major periodontal pathogens in subgingival plaque samples from subjects with chronic periodontitis. Materials and methods: 40 subgingival plaque samples were obtained from periodontitis and healthy sites of 10 khat chewers (40 y median age) and 10 khat non-chewers (37.5 y median age) with chronic periodontiti...

Al-hebshi, Nezar Noor; Al-sharabi, Ali Kaid; Shuga-aldin, Hussein Mohammed; Al-haroni, Mohammed; Ghandour, Ibrahim

2010-01-01

309

Meniscus and ligament injuries  

International Nuclear Information System (INIS)

The knee is one of the major weight-bearing joints and is relatively exposed to trauma. Capsuloligamentous structures are essential to provide joint stability and - in turn - persistent instability bears a risk for osteoarthritis that needs timely and comprehensive diagnosis. Using MRI it may be beneficial to routinely apply (T)SE sequences in all three major planes as a basic protocol and to add additional sequences according to the clinical information available and imaging findings in the basic protocol. Especially fat-suppressed sequences (STIR, T2w/PDw FS TSE) are very useful because they sensitively depict bone marrow edema pattern (BMEP)-like changes. This finding often alerts the reader to - sometimes only discrete - underlying pathologies and may - if found in typical locations - give information about the mechanism of injury and thus lead the radiologist to look for specific concomitant capsuloligamentous, cartilage, and/or meniscal injury. BMEP is quite prominent in contusion injury, whereas often it is but discrete in avulsion lesions. There is extensive literature about the signs, possible pitfalls, and the accuracy of MRI for the diagnosis of specific pathologies such as meniscal tears or cruciate or collateral ligament ruptures. However, combined injuries of more than one structure are frequent and affect the therapeutic approach. Thus, the primary goal of the radiologist is to go beyond the description of any isolated lesion and to give a comprehensivesolated lesion and to give a comprehensive description of (or to reliably exclude) any injury to other structures. A necessary prerequisite to accomplish this is a thorough knowledge of the - in some locations - complex anatomic relationships, pitfalls, and locations where lesions typically occur and where they may be overlooked. (orig.)

310

Neutrophil Chemotaxis Dysfunction in Human Periodontitis  

OpenAIRE

Polymorphonuclear leukocyte (PMNL) chemotaxis studies of 32 patients with localized juvenile periodontitis (periodontosis or LJP), 10 adult patients with a history of LJP (post-LJP), 8 patients with generalized juvenile periodontitis (GJP), and 23 adults with moderate to severe periodontitis were performed: (i) to determine the prevalence of a PMNL chemotaxis defect in a large group of LJP patients; (ii) to study PMNL chemotaxis in patients with other forms of severe periodontal disease; and ...

Dyke, T. E.; Horoszewicz, H. U.; Cianciola, L. J.; Genco, R. J.

1980-01-01

311

ASSOCIATION OF SERUM ALBUMIN CONCENTRATION AND PERIODONTITIS  

OpenAIRE

Periodontal disease is a complex, multi-factorial, chronic inflammatory disease that involves degradation of periodontal structures, including alveolar bone. Many systemic diseases and disorders have been implicated as risk indicators or risk factors in periodontal disease. Clinical and basic science research over the past several decades have led to an improved understanding and appreciation for the complexity and pathogenesis of periodontal diseases. It has been indicated that there might b...

Ramesh Amitha; John Anju Mary; Thomas Biju; Suchetha Kumari; Nishana Fathimath K

2012-01-01

312

Antibiotics in the management of aggressive periodontitis  

OpenAIRE

Aggressive periodontitis, although not rare, is a fairly unknown condition. Little is known about its optimal management. While majority of patients with common forms of periodontal disease respond predictably well to conventional therapy (oral hygiene instructions (OHI), non-surgical debridement, surgery, and Supportive Periodontal therapy (SPT)), patients diagnosed with aggressive form of periodontal disease often do not respond predictably/favorably to conventional therapy owing to its com...

Prakasam, Abinaya; Elavarasu, S. Sugumari; Natarajan, Ravi Kumar

2012-01-01

313

Evaluation of Menstrual Cycle on Periodontal Parameters  

OpenAIRE

Introduction: Bacterial plaque has been identified as the primary factor for the onset of periodontal disease. Although pathogens are very important in the pathogenesis of periodontal diseases, the hosts’ systemic and predisposing factors should also be considered. Sex hormones are important factors contributing to periodontal diseases. The purpose of this study was to investigate the effects of menstruation cycle on periodontal indices. Materials & Methods: In this study, 20 premenopausal ...

Naser Sargolzaee; MohammadHasan NajafiNashli; MajidReza Mokhtari; Nayereh FasihiFard; Elham Nik; Fatemeh Farazi

2013-01-01

314

Subgingival and Tongue Microbiota during Early Periodontitis  

OpenAIRE

Periodontal infections have a microbial etiology. Association of species with early disease would be useful in determining which microbes initiate periodontitis. We hypothesized that the microbiota of subgingival and tongue samples would differ between early periodontitis and health. A cross-sectional evaluation of 141 healthy and early periodontitis adults was performed with the use of oligonucleotide probes and PCR. Most species differed in associations with sample sites; most subgingival s...

Tanner, A. C. R.; Paster, B. J.; Lu, S. C.; Kanasi, E.; Kent, R.; Dyke, T.; Sonis, S. T.

2006-01-01

315

Activation of Neutrophil Collagenase in Periodontitis  

OpenAIRE

Neutrophil collagenase (matrix metalloproteinase 8 [MMP-8]) is an important mediator of tissue destruction in inflammatory diseases. Studies of anaerobic periodontal infections have shown that active MMP-8 in gingival crevicular fluid is associated with the degradation of periodontal tissues in progressive periodontitis whereas the latent enzyme is predominant in gingivitis. Since the activation of MMP-8 appears to be a crucial step in periodontitis, we have examined the activation of MMP-8 i...

Romanelli, Raquel; Mancini, Sabrina; Laschinger, Carol; Overall, Christopher M.; Sodek, Jaro; Mcculloch, Christopher A. G.

1999-01-01

316

Common Periodontal Diseases of Children and Adolescents  

OpenAIRE

Background. Since 2000, studies, experiments, and clinical observations revealed high prevalence of periodontal diseases among children and adolescents. Therefore, this paper was designed to provide an update for dental practitioners on epidemiology, microbiology, pathology, prevention, diagnosis, and treatment of periodontal diseases in children and adolescents. Methods. This paper reviews the current literature concerning periodontal diseases in pediatric dentistry. It includes MEDLINE data...

Hayat Al-Ghutaimel; Hisham Riba; Salem Al-Kahtani; Saad Al-Duhaimi

2014-01-01

317

Anterior cruciate ligament allograft transplantation for intraarticular ligamentous reconstruction.  

Science.gov (United States)

A multiplicity of surgical operations have been developed in an attempt to achieve satisfactory function after anterior cruciate ligament (ACL) repair. None of these procedures have been able to reproduce the fiber organization anatomy of attachment site, vascularity, or function of the ACL. Twenty-nine foxhounds received a deep-frozen bone-ACL-bone allograft and a ligament augmentation device (LAD). Biomechanical, microvascular, and histological changes were evaluated 3, 6, and 12 months following implantation. The maximum loads of the allograft/LADs were 34.3% (387.2 N) after 3 months, 49.3% (556.6 N) after 6 months, and 61.1% (698.8 N) after a year. The maximum load was 69.1% (780 N). In general, after 6 months the allografts showed normal collagen orientation. The allografts demonstrated no evidence of infection or immune reaction. No bone ingrowth into the LAD was observed. Polarized light microscopy and periodic acid-schiff staining showed that the new bone-ligament substance interface had intact fiber orientation at the area of the ligament insertion. Microvascular examination using the Spalteholtz technique revealed revascularization and the importance of an infrapatellar fat pad for the nourishment of ACL allografts. PMID:1389780

Goertzen, M; Dellmann, A; Gruber, J; Clahsen, H; Bürrig, K F

1992-01-01

318

Direct pulp capping using biodentine  

OpenAIRE

Introduction. Direct pulp capping is therapeutic method of applying medication on exposed pulp in order to allow bridge formation and healing process. The aim of this study was to investigate the effect of Biodentine on exposed dental pulp of Vietnamese pigs. Material and Methods. The study was conducted on 20 teeth of Vietnamese pigs (Sus scrofa domesticus). On buccal surfaces of incisors, canines and first premolars, class V cavities were prepared and pul...

Popovi?-Baji? Marijana; Danilovi? Vesna; Proki? Branislav; Proki? Bogomir; Jokanovi? Vukoman; Živkovi? Slavoljub

2014-01-01

319

Modeling pulp fiber suspension rheology  

OpenAIRE

Rheological properties of pulp suspensions play a very important role in the industry, mainly due to the consumption of energy for transporting pulp among the different parts of the paper mill. In this work, we determined the rheology of long- and short-fiber bleached kraft pulp suspensions by using a new rotational viscometer especially designed for their analysis. The experimental rheograms were adjusted to the Herschel-Bulkley model. We established the dependence of the rheological p...

Ventura, Carla; Blanco, Angeles; Negro, Carlos; Ferreira, Paulo; Garcia, Fernando; Rasteiro, Maria

2007-01-01

320

Direct pulp capping using biodentine  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction. Direct pulp capping is therapeutic method of applying medication on exposed pulp in order to allow bridge formation and healing process. The aim of this study was to investigate the effect of Biodentine on exposed dental pulp of Vietnamese pigs. Material and Methods. The study was conducted on 20 teeth of Vietnamese pigs (Sus scrofa domesticus. On buccal surfaces of incisors, canines and first premolars, class V cavities were prepared and pulp was exposed. In the experimental group (six incisors, two canines and two premolars the perforation was covered with Biodentine® (Septodont, Saint-Maur-des-Fosses, France. In the control group, the perforation was covered with MTA® (Dentsply Tulsa Dental, Johnson City, TN, USA. All cavities were restored with glass ionomer cement (GC Fuji VIII, GC Corporation, Tokyo, Japan. Observation period was 28 days. After sacrificing the animals, histological preparations were done to analyze the presence of dentin bridge, an inflammatory reaction of the pulp, pulp tissue reorganization and the presence of bacteria. Results. Dentin bridge was observed in all teeth (experimental and control groups. Inflammation of the pulp was mild to moderate in both groups. Neoangiogenesis and many odontoblast like cells responsible for dentin bridge formation were detected. Necrosis was not observed in any case, neither the presence of Gram-positive bacteria in the pulp. Conclusion. Histological analysis indicated favorable therapeutic effects of Biodentine for direct pulp capping in teeth of Vietnamese pigs. Findings were similar with Biodentine and MTA.

Popovi?-Baji? Marijana

2014-01-01

321

Different effects of 25-kDa amelogenin on the proliferation, attachment and migration of various periodontal cells  

Energy Technology Data Exchange (ETDEWEB)

Previous studies have assumed that amelogenin is responsible for the therapeutic effect of the enamel matrix derivative (EMD) in periodontal tissue healing and regeneration. However, it is difficult to confirm this hypothesis because both the EMD and the amelogenins are complex mixtures of multiple proteins. Further adding to the difficulties is the fact that periodontal tissue regeneration involves various types of cells and a sequence of associated cellular events including the attachment, migration and proliferation of various cells. In this study, we investigated the potential effect of a 25-kDa recombinant porcine amelogenin (rPAm) on primarily cultured periodontal ligament fibroblasts (PDLF), gingival fibroblasts (GF) and gingival epithelial cells (GEC). The cells were treated with 25-kDa recombinant porcine amelogenin at a concentration of 10 {mu}g/mL. We found that rPAm significantly promoted the proliferation and migration of PDLF, but not their adhesion. Similarly, the proliferation and adhesion of GF were significantly enhanced by treatment with rPAm, while migration was greatly inhibited. Interestingly, this recombinant protein inhibited the growth rate, cell adhesion and migration of GEC. These data suggest that rPAm may play an essential role in periodontal regeneration through the activation of periodontal fibroblasts and inhibition of the cellular behaviors of gingival epithelial cells.

Li, Xiting [Department of Periodontology, Ninth People' s Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai Key Laboratory of Stomatology, No. 639 Zhi Zao Ju Road, Shanghai 200011 (China); Shu, Rong, E-mail: shurong123@hotmail.com [Department of Periodontology, Ninth People' s Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai Key Laboratory of Stomatology, No. 639 Zhi Zao Ju Road, Shanghai 200011 (China); Liu, Dali; Jiang, Shaoyun [Department of Periodontology, Ninth People' s Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai Key Laboratory of Stomatology, No. 639 Zhi Zao Ju Road, Shanghai 200011 (China)

2010-04-09

322

Different effects of 25-kDa amelogenin on the proliferation, attachment and migration of various periodontal cells  

International Nuclear Information System (INIS)

Previous studies have assumed that amelogenin is responsible for the therapeutic effect of the enamel matrix derivative (EMD) in periodontal tissue healing and regeneration. However, it is difficult to confirm this hypothesis because both the EMD and the amelogenins are complex mixtures of multiple proteins. Further adding to the difficulties is the fact that periodontal tissue regeneration involves various types of cells and a sequence of associated cellular events including the attachment, migration and proliferation of various cells. In this study, we investigated the potential effect of a 25-kDa recombinant porcine amelogenin (rPAm) on primarily cultured periodontal ligament fibroblasts (PDLF), gingival fibroblasts (GF) and gingival epithelial cells (GEC). The cells were treated with 25-kDa recombinant porcine amelogenin at a concentration of 10 ?g/mL. We found that rPAm significantly promoted the proliferation and migration of PDLF, but not their adhesion. Similarly, the proliferation and adhesion of GF were significantly enhanced by treatment with rPAm, while migration was greatly inhibited. Interestingly, this recombinant protein inhibited the growth rate, cell adhesion and migration of GEC. These data suggest that rPAm may play an essential role in periodontal regeneration through the activation of periodontal fibroblasts and inhibition of the cellular behaviors of gingival epithelial cells.

323

High glucose improves healing of periodontal wound by inhibiting proliferation and osteogenetic differentiation of human PDL cells.  

Science.gov (United States)

Periodontal ligament (PDL) cells play an important role in wound healing of periodontal tissues. Response of PDL cells' cellular activity to high-glucose concentration levels may be the key in understanding the relationship between periodontal disease and diabetes mellitus. We studied the effect of high-glucose medium on proliferation of PDL cells in vitro. PDL cells were cultured for 1, 4, 7, 10, 14 and 17?days in normal (1100?mg/l) glucose or in high (4500?mg/l) glucose medium. The 3-(4,5-dimethylithiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay for proliferation was performed. In order to evaluate the osteogenetic differentiation of human PDL cells, the cells were induced with normal- or high-glucose medium for 1, 7, 14, 21 and 28?days. The results indicated that high glucose significantly inhibited proliferation of PDL cells. Concerning the mineralised nodule formation, the percentage of calcified area to total culture dish of PDL cells in high glucose level was lower than that in normal glucose medium. The increase in alkaline phosphatase activity and collagen expression could be observed in high-glucose-containing osteogenetic factor. In conclusion, high glucose improves healing of periodontal wound by inhibiting proliferation and differentiation of PDL cells, which could explain for delayed periodontal regeneration and healing in diabetic patients. PMID:24581427

Li, Min; Li, Cheng-Zhang

2014-02-28

324

CT-arthrography of the cruciate ligaments  

Energy Technology Data Exchange (ETDEWEB)

The evaluation of the cruciate ligaments using CT in 218 patients shall be presented. An intraarticular administration of air must be performed. Special positionings are required in order to bring the axis of the cruciate ligaments into the cross-sectional plane of the CT. The normal appearance of the cruciate ligaments in CT-arthrography is described. A classification of the anterior cruciate ligament lesions with 4 different types is proposed. The four types of the anterior cruciate ligament lesions and the posterior cruciate ligament lesions are met with different frequency. For CT-arthrography a sensitivity of 93% and a specifity of 95% was found. In patients with previous reconstructive surgery of the cruciate ligaments the results can be objectively documented. Thus CT-arthrography can contribute in the diagnosis of postoperative complaints.

Reiser, M.; Rupp, N.; Feuerbach, S.; Anacker, H.; Karpf, P.M.

1981-09-01

325

CT-arthrography of the cruciate ligaments  

International Nuclear Information System (INIS)

The evaluation of the cruciate ligaments using CT in 218 patients shall be presented. An intraarticular administration of air must be performed. Special positionings are required in order to bring the axis of the cruciate ligaments into the cross-sectional plane of the CT. The normal appearance of the cruciate ligaments in CT-arthrography is described. A classification of the anterior cruciate ligament lesions with 4 different types is proposed. The four types of the anterior cruciate ligament lesions and the posterior cruciate ligament lesions are met with different frequency. For CT-arthrography a sensitivity of 93% and a specifity of 95% was found. In patients with previous reconstructive surgery of the cruciate ligaments the results can be objectively documented. Thus CT-arthrography can contribute in the diagnosis of postoperative complaints. (orig.)

326

A scanning electron-microscopic, stereo-pair study of methacrylate corrosion casts of the mouse palatal and molar periodontal microvasculature.  

Science.gov (United States)

Microvascular beds of the palate, gingiva and periodontal ligament had interconnected but distinct, regional patterns. The palatal vasculature reflected mucosal-crest morphology: crestal capillary vessels of the rugae anastomosed with sagitally-orientated rows of 8 microns capillary loops, and, in the inter-rugal troughs, these formed a flat plexus overlying collecting veins more than 100 microns in diameter. Maxillary and mandibular molar ligaments had similar microvascular patterns. The molar gingiva had a circular, outer capillary and inner venous system linked by radial anastomoses. The outer (7 microns) capillaries enclosed the three molars in a continuous horizontal loop coursing beneath the crestal epithelium; the inner (10-15 microns) venous vessels encircled each molar just below the epithelial attachment. Glomerulus-like vascular formations, with an arterial and venous stalk, were associated with the inner circular system and extended toward the crevicular epithelium. Axially aligned, post-capillary, periodontal-ligament vessels (21 microns) anastomosed with the inner circular system, forming different patterns in the occlusal, middle and apical thirds. The apical pattern comprised an enveloping plexus of anastomosing venous vessels supplied by arterio-venous shunts; similar shunts were present throughout the ligament. The microvascular bed of the mandibular inter-radicular ligament was characterized by the presence of a large venous ampulla measuring 60 by 200 microns. Some regions of the ligament microvasculature drained via the medullary vessels into 50 microns-diameter venules located interdentally deep to the molar apices. Volumetrically, the ligament microvascular bed was predominantly of post-capillary venules, and morphologically, a paired arterial and venous system was not demonstrated. PMID:3479097

Wong, R S; Sims, M R

1987-01-01

327

LIGAMENT-CONTROLLED EFFERVESCENT ATOMIZATION  

Science.gov (United States)

The operating principles and performance of a new type of spray nozzle are presented. This nozzle, termed a "ligament-controlled effervescent atomizer," was developed to allow consumer product manufacturers to replace volatile organic compound (VOC) solvents with water and hydroc...

328

Gene therapy and its implications in Periodontics  

Directory of Open Access Journals (Sweden)

Full Text Available Gene therapy is a field of Biomedicine. With the advent of gene therapy in dentistry, significant progress has been made in the control of periodontal diseases and reconstruction of dento-alveolar apparatus. Implementation in periodontics include: -As a mode of tissue engineering with three approaches: cell, protein-based and gene delivery approach. -Genetic approach to Biofilm Antibiotic Resistance. Future strategies of gene therapy in preventing periodontal diseases: -Enhances host defense mechanism against infection by transfecting host cells with an antimicrobial peptide protein-encoding gene. -Periodontal vaccination. Gene therapy is one of the recent entrants and its applications in the field of periodontics are reviewed in general here.

Mahale Swapna

2009-01-01

329

Immunolocalization of RANK and RANKL along the root surface and in the periodontal membrane of human primary and permanent teeth  

DEFF Research Database (Denmark)

Abstract Objective. Root resorption, impaired tooth eruption and early tooth loss have been described in relation to diseases that involve defects in the RANK-RANKL-OPG-expression. The aim of the present immunhistochemical study was to localize and compare the reactions for RANK and membrane-bound RANKL along root surfaces and in the periodontal membrane in close proximity to the root surface of human primary and permanent teeth. Materials and methods. The material comprised extracted human teeth (11 primary teeth and six permanent teeth) from 10 different patients. Paraffin sections were prepared of each tooth and sections of each tooth were immunohistochemically stained with antibodies specific for membrane-bound RANKL and RANK. Results. The root surface and the periodontal membrane in close proximity to the root surface did not show immunoreactivity for RANKL. RANKL was only located in odontoblasts and in cells along denticles in one primary tooth. RANK was located in mononuclear cells in the pulp and in multinucleated odontoclasts along resorbed root surfaces and along resorbed dentin surfaces in the pulp in primary teeth and one permanent tooth. Conclusions. This study demonstrated RANK positivity in resorption areas in primary and permanent teeth. RANKL was positive in the pulp of one primary tooth. RANK expression in odontoclasts and RANKL expression in the pulp may indicate that RANK/RANKL play a role during resorption.

Bille, Marie-Louise Bastholm; Thomsen, Bjarke

2012-01-01

330

Features of morphofunctional changes in periodontal tissue in patients with chronic parodontitis and periodontitis  

Directory of Open Access Journals (Sweden)

Full Text Available The features of the morphological changes in the periodontal tissues in the cervical and periapical areas in different forms of chronic parodontitis and periodontitis were studied. Under supervision there were patients diagnosed with chronic granulomatous periodontitis and chronic parodontitis. Data of investigation suggest the existence of differences in morpho-logical and functional properties of the periodontal tissues of chronic periodontitis. Patients with chronic granulomatous peri-odontitis can be divided into three groups: patients with a predominance of inflammatory changes, with a predominance of degenerative changes and mixed form. On X-ray imaging to set histological differentiation into subgroups was not possible. These data suggest the existence of differences of morphological and functional changes in the properties of periodontal tissue in chronic periodontitis, namely the prevalence of inflammatory or degenerative changes that require a differentiated approach to the treatment of chronic periodontitis include data pathomorphological study.

Kernytskyy R.V.

2012-01-01

331

Recording and surveillance systems for periodontal diseases  

DEFF Research Database (Denmark)

This paper describes tools used to measure periodontal diseases and the integration of these tools into surveillance systems. Tools to measure periodontal diseases at the surveillance level have focussed on current manifestations of disease (e.g. gingival inflammation) or disease sequelae (e.g. periodontal pocket depth or loss of attachment). All tools reviewed in this paper were developed based on the state of the science of the pathophysiology of periodontal disease at the time of their design and the need to provide valid and reliable measurements of the presence and severity of periodontal diseases. Therefore, some of these tools are no longer valid. Others, such as loss of periodontal attachment, are the current de-facto tools but demand many resources to undertake periodical assessment of the periodontal health of populations. Less complex tools such as the Community Periodontal Index, have been used extensively to report periodontal status. Laboratory tests for detecting putative microorganisms or inflammatory agents present in periodontal diseases have been used at the clinical level, and at least one has been tested at the population level. Other approaches, such as self-report measures, are currently under validation. In this paper, we do not review indices designed to measure plaque or residual accumulation around the tooth, indices focussed only on gingival inflammation or radiographic approaches with limited applicability in surveillance systems. Finally, we review current case-definitions proposed for surveillance of periodontal disease severity.

Beltrán-Aguilar, Eugenio D; Eke, Paul I

2012-01-01

332

Lessons learned and unlearned in periodontal microbiology.  

Science.gov (United States)

Periodontal diseases are initiated by bacterial species living in polymicrobial biofilms at or below the gingival margin and progress largely as a result of the inflammation elicited by specific subgingival species. In the past few decades, efforts to understand the periodontal microbiota have led to an exponential increase in information about biofilms associated with periodontal health and disease. In fact, the oral microbiota is one of the best-characterized microbiomes that colonize the human body. Despite this increased knowledge, one has to ask if our fundamental concepts of the etiology and pathogenesis of periodontal diseases have really changed. In this article we will review how our comprehension of the structure and function of the subgingival microbiota has evolved over the years in search of lessons learned and unlearned in periodontal microbiology. More specifically, this review focuses on: (i) how the data obtained through molecular techniques have impacted our knowledge of the etiology of periodontal infections; (ii) the potential role of viruses in the etiopathogenesis of periodontal diseases; (iii) how concepts of microbial ecology have expanded our understanding of host-microbe interactions that might lead to periodontal diseases; (iv) the role of inflammation in the pathogenesis of periodontal diseases; and (v) the impact of these evolving concepts on therapeutic and preventive strategies to periodontal infections. We will conclude by reviewing how novel systems-biology approaches promise to unravel new details of the pathogenesis of periodontal diseases and hopefully lead to a better understanding of their mechanisms. PMID:23574465

Teles, Ricardo; Teles, Flavia; Frias-Lopez, Jorge; Paster, Bruce; Haffajee, Anne

2013-06-01

333

Indirect pulp treatment in a permanent molar: case reort of 4-year follow-up  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english This case report describes the Indirect Pulp Treatment (IPT) of deep caries lesion in a permanent molar. A 16-year-old male patient reported discomfort associated with thermal stimulation on the permanent mandibular left first molar. The radiographs revealed a deep distal caries lesion, very close t [...] o the pulp, absence of radiolucencies in the periapical region, and absence of periodontal space thickening. Pulp sensitivity was confirmed by thermal pulp vitality tests. Based on the main complaint and the clinical and radiographic examinations, the treatment plan was established to preserve pulp vitality. Clinical procedures consisted of removing the infected dentin and lining the caries-affected dentin with calcium hydroxide paste. The tooth was provisionally sealed for approximately 60 days. After this period, tooth vitality was confirmed, the remaining carious dentin was removed, and the tooth was restored. At 4-year follow-up, no clinical or radiographic pathological findings were found.

Ticiane Cestari, Fagundes; Terezinha Jesus Esteves, Barata; Anuradha, Prakki; Eduardo, Bresciani; José Carlos, Pereira.

2009-02-01

334

Periapical fluid RANKL and IL-8 are differentially regulated in pulpitis and apical periodontitis.  

Science.gov (United States)

The dental pulp space can become infected due to a breach in the surrounding hard tissues. This leads to inflammation of the pulp (pulpitis), soft tissue breakdown, and finally to bone loss around the root apex (apical periodontitis). The succession of the molecular events leading to apical periodontitis is currently not known. The main inflammatory mediator associated with neutrophil chemotaxis is interleukin-8 (IL-8), and with bone resorption the dyad of receptor activator of NF-?B ligand (RANKL) and osteoprotegerin (OPG). The levels of RANKL, OPG and IL-8 were studied in periapical tissue fluid of human teeth (n = 48) diagnosed with symptomatic irreversible pulpitis (SIP) and asymptomatic apical periodontitis (AAP). SIP represents the starting point, and AAP an established steady state of the disease. Periapical tissue fluid samples were collected using paper points and then evaluated using enzyme-linked immunosorbent assays (ELISAs). Target protein levels per case were calibrated against the corresponding total protein content, as determined fluorometrically. RANKL was expressed at significantly higher levels in SIP compared to AAP (P < 0.05), whereas OPG was under the detection limit in most samples. In contrast, IL-8 levels were significantly lower in SIP compared to AAP (P < 0.05). Spearman's correlation analysis between RANKL and IL-8 revealed a significantly (P < 0.05) negative correlation between the two measures (rho = -.44). The results of this study suggest that, in the development of apical periodontitis, periapical bone resorption signaling, as determined by RANKL, occurs prior to inflammatory cell recruitment signaling, as determined by IL-8. PMID:25022970

Rechenberg, Dan-K; Bostanci, Nagihan; Zehnder, Matthias; Belibasakis, Georgios N

2014-09-01

335

TRATAMIENTO ORTODÓNCICO Y PERIODONTAL COMBINADO EN PACIENTES CON PERIODONTITIS AGRESIVA TRATADA Y CONTROLADA / COMBINED ORTHODONTIC-PERIODONTAL TREATMENT IN PATIENTS WITH TREATED AND CONTROLLED AGGRESSIVE PERIODONTITIS  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish Para diagnosticar correctamente la periodontitis agresiva (PA) se debe tener en cuenta la información obtenida de la entrevista con el paciente, examen clínico periodontal, radiográfico y de laboratorio, según necesidad. El tratamiento de la PA va encaminado a la reducción o eliminación de los agent [...] es causales, manejo de los factores de riesgo y la corrección de los efectos de la enfermedad sobre los tejidos periodontales. Cuando se pretende realizar un tratamiento de ortodoncia en un paciente con PA, se requiere una evaluación detallada por ambas especialidades. Este artículo describe la terapia periodontal y ortodóncica combinada en cuatro pacientes jóvenes con periodontitis agresiva localizada (PAL) y periodontits agresiva generalizada (PAG). En primer lugar, se llevó a cabo un tratamiento periodontal completo. Una vez que se confirmó la ausencia de inflamación y la estabilidad del periodonto, se inició el tratamiento de ortodoncia utilizando fuerzas ligeras acompañadas de un monitoreo periodontal, alcanzando los objetivos estéticos y funcionales planteados al inicio del tratamiento. Abstract in english Accurate diagnosis of aggressive periodontitis (AP) requires taking into account information obtained from the interview with the patient and from clinical periodontal examination, radiographic evaluation, and laboratory tests when needed. AP treatment is aimed at reducing or eliminating triggering [...] agents, managing risk factors, and correcting effects on periodontal tissues. Before starting orthodontic treatment in an AP patient, it is necessary to perform a detailed evaluation by both specialties. This article describes a combined periodontal-orthodontic therapy in four young patients with localized aggressive periodontitis (LAP) and generalized aggressive periodontitis (GAP). A complete periodontal treatment was first conducted. After completely reducing inflammation and stabilizing the periodontium, the clinicians started the orthodontic treatment by using moderate forces along with periodontal monitoring, thus reaching the aesthetic and functional objectives set when treatment started.

Juan Fernando, Aristizábal; Rosana, Martínez Smit.

2014-12-01

336

Aggressive and acute periodontal diseases.  

Science.gov (United States)

Inflammatory periodontal diseases are highly prevalent, although most of these diseases develop and progress slowly, often unnoticed by the affected individual. However, a subgroup of these diseases include aggressive and acute forms that have a relatively low prevalence but show a rapid-course, high rate of progression leading to severe destruction of the periodontal tissues, or cause systemic symptoms that often require urgent attention from healthcare providers. Aggressive periodontitis is an early-onset, destructive disease that shows a high rate of periodontal progression and distinctive clinical features. A contemporary case definition of this disease is presented. Population studies show that the disease is more prevalent in certain geographic regions and ethnic groups. Aggressive periodontitis is an infectious disease, and recent data show that in affected subjects the subgingival microbiota is composed of a mixed microbial infection, with a wide heterogeneity in the types and proportions of microorganisms recovered. Furthermore, there are significant differences in the microbiota of the disease among different geographic regions and ethnicities. There is also evidence that the Aggregatibacter actinomycetemycomitans-JP2 clone may play an important role in the development of the disease in certain populations. The host response plays an important role in the susceptibility to aggressive periodontitis, where the immune response may be complex and involve multiple mechanisms. Also, genetic factors seem to play an important role in the pathogenesis of this disease, but the mechanisms of increased susceptibility are complex and not yet fully understood. The available data suggest that aggressive periodontitis is caused by mutations either in a few major genes or in multiple small-effect genes, and there is also evidence of gene-gene and gene-environment interaction effects. Diagnostic methods for this disease, based on a specific microbiologic, immunologic or genetic profile, currently do not exist. Genetic markers have the potential to be implemented as screening tools to identify subjects at risk. This approach may significantly enhance treatment outcome through the early detection and treatment of affected subjects, as well as using future approaches based on gene therapy. At present, the treatment of this disease is directed toward elimination of the subgingival bacterial load and other local risk factors. Adjunctive use of appropriate systemic antibiotics is recommended and may contribute to a longer suppression of the microbial infection. Other aggressive forms of periodontal diseases occur in patients who are affected with certain systemic diseases, including the leukocyte adhesion deficiency syndrome, Papillon-Lefèvre syndrome, Chediak-Higashi syndrome and Down syndrome. Management of the periodontal component of these diseases is very challenging. Acute gingival and periodontal lesions include a group of disorders that range from nondestructive to destructive forms, and these lesions are usually associated with pain and are a common reason for emergency dental consultations. Some of these lesions may cause a rapid and severe destruction of the periodontal tissues and loss of teeth. Oral infections, particularly acute infections, can spread to extra-oral sites and cause serious medical complications, and even death. Hence, prompt diagnosis and treatment are paramount. PMID:24738583

Albandar, Jasim M

2014-06-01

337

MR imaging findings in spring ligament insufficiency  

International Nuclear Information System (INIS)

Objective. Spring ligament insufficiency is associated with chronic posterior tibial tendon dysfunction, and may constitute an indication for surgical repair or reconstruction. This study examines the accuracy of MRI for the diagnosis of insufficiency of the spring ligament. Design and patients. Two experienced musculoskeletal radiologists independently scored the MRI findings in 13 cases of surgically proven spring ligament insufficiency and in 18 control subjects, using a standardized scoring system. Results. Insufficiency of the spring ligament was associated with increased signal heterogeneity on short TE spin echo images, and an increase in the thickness of the medial portion of the ligament. The sensitivity of MRI for the diagnosis of spring ligament insufficiency was 54-77%, while the specificity was 100%. MRI assessment of the plantar portion of the spring ligament was unreliable (kappa=0.33), but the assessment of global ligament integrity was substantially reproducible (kappa=0.76). Conclusion. The medial portion of the spring ligament can be reliably assessed on routine MRI. The findings of spring ligament insufficiency on MRI are only moderately sensitive but highly specific. (orig.)

338

Accelerated coffee pulp composting.  

Science.gov (United States)

The effect of two abundant, easily available and very low-cost agro-industrial organic residues, i.e., filter cake from the sugar industry and poultry litter, on the composting stabilization time of coffee pulp and on the quality of the produced compost, was evaluated. Piles of one cubic meter were built and monitored within the facilities of a coffee processing plant in the Coatepec region of the State of Veracruz, Mexico. Manual aeration was carried out once a week. A longer thermophilic period (28 days) and a much lower C/N ratio (in the range of 6.9-9.1) were observed in the piles containing the amendments, as compared to the control pile containing only coffee pulp (14 days and a C/N ratio of 14.4, respectively). The maximum assimilation rate of the reducing sugars was 1.6 g kg-1 d-1 (from 7.5 to 5.3%) during the first two weeks when accelerators were present in the proportion of 20% filter cake plus 20% poultry litter, while they accumulated at a rate of 1.2 g kg-1 d-1 (from 7.4 to 9.13%) during the same period in the control pile. The best combination of amendments was 30% filter cake with 20% poultry litter, resulting in a final nitrogen content as high as 4.81%. The second best combination was 20% filter cake with 10% poultry litter, resulting in a compost which also contained a high level of total nitrogen (4.54%). It was concluded that the use of these two residues enhanced the composting process of coffee pulp, promoting a shorter stabilization period and yielding a higher quality of compost. PMID:10423839

Sánchez, G; Olguín, E J; Mercado, G

1999-02-01

339

NEWSPRINT FROM SODA BAGASSE PULP IN ADMIXTURE WITH HARDWOOD CMP PULP  

Directory of Open Access Journals (Sweden)

Full Text Available Based on global research and experiences producing newsprint from bagasse, the possibility of using bagasse chemical pulp in the furnish of local mill-made mixed hardwood CMP pulp was studied at laboratory scale, for making newsprint. Bagasse soda chemical pulp at digester yield of about 47% was bleached to about 60% brightness by single stage hydrogen peroxide. The effects of using up to 30% bagasse chemical pulp in a blend with hardwood CMP pulp, with or without softwood kraft pulp, were studied. The results showed that superior hand sheet properties could be achieved by using bagasse chemical pulp; in comparison with main mill pulp furnish (83% hardwood CMP pulp and 17% imported long fiber pulp. In other words, by using bagasse chemical pulp in a blend with local mill made hardwood CMP pulp, acceptable newsprint could be made with considerable reduction in the consumptions of hardwood species and softwood reinforcing kraft pulp.

Seed Rahman Jafari Petroudy

2011-05-01

340

Effects of a low level laser on periodontal tissue in hypofunctional teeth.  

Science.gov (United States)

Malocclusions, such as an open bite and high canines, are often encountered in orthodontic practice. Teeth without occlusal stimuli are known as hypofunctional teeth, and numerous atrophic changes have been reported in the periodontal tissue, including reductions in blood vessels in the periodontal ligament (PDL), heavy root resorption, and reduced bone mineral density (BMD) in the alveolar bone. Low Level Laser (LLL) has been shown to have a positive effect on bone formation and the vasculature. Although the recovery of hypofunctional teeth remains unclear, LLL is expected to have a positive influence on periodontal tissue in occlusal hypofunction. The aim of the present study was to elucidate the relationship between LLL and periodontal tissue in occlusal hypofunction. Twenty-four male rats aged 5 weeks were randomly divided into control and hypofunctional groups. An anterior metal cap and bite plate were attached to the maxillary and mandibular incisors in the hypofunctional group to simulate occlusal hypofunction in the molars. LLL irradiation was applied to the maxillary first molar through the gingival sulcus in half of the rats. Rats were divided into four groups; control, control+LLL, hypofunctional, and hypofunctional+LLL. Exposure to LLL irradiation was performed for 3 minutes every other day for 2 weeks. Animals were examined by Micro-CT at 5 and 7 weeks and were subsequently sacrificed. Heads were resected and examined histologically and immunohistologically. The hypofunctional group had obvious stricture of the PDL. However, no significant differences were observed in the PDL and alveolar bone between the hypofunctional+LLL and the control groups. In addition, the expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF)-positive cells were higher in the hypofunctional + LLL group than in the hypofunctional group. These results indicated that LLL enhanced the production of bFGF and VEGF in the periodontal tissue of hypofunctional teeth. PMID:24927024

Hayashi, Hidetaka; Terao, Akiko; Kunimatsu, Ryo; Kawata, Toshitsugu

2014-01-01

341

Periodontal Status of Postmenopausal Women  

Directory of Open Access Journals (Sweden)

Full Text Available The objective of this study was to compare the periodontal status in postmenopausal women with osteopenia and osteoporosis. Material and Methods: We examined 43 postmenopausal women aged from 55 to 74 years. Material assessment of bones in every patient was performed by means of dual energy X-ray absorptiometry (DXA from two points on the skeleton – part of the femur neck and between the first and fourth lumbar vertebrae. A lipid blood test was done for patients of both groups. All patients were divided into two groups (the 1st with osteopenia, and the 2nd with osteoporosis. All patients were subjected to an oral clinical examination: the periodontal examination was composed of Plaque Index (PI, Pocket Score (PS, and Papillary Bleeding Index (PBI. X-ray analysis was performed for every patient. Results: The results of the clinical periodontal examination demonstrated that the mean PBI in patients in the 1st group had no significant differences from the PBI in patients in the 2nd group. PI value and PS findings in patients with general osteoporosis also had no statistical differences from the same parameters in patients with osteopenia. Conclusion: Under the circumstances of these patients’ characteristics and within the limits of the present study, we concluded that there is no significant difference in the periodontal status of postmenopausal women with systemic osteopenia and with osteoporosis.

Timur V. Melkumyan

2014-06-01

342

Healing ligaments have decreased cyclic modulus compared to normal ligaments and immobilization further compromises healing ligament response to cyclic loading.  

Science.gov (United States)

Ligaments help maintain joint stability by resisting excessive strain during the repetitive loading experienced during daily activity. Healing ligaments may be less able to fulfill this role, straining more under equivalent loading than normal ligaments. We examined the cyclic stress-strain response of normal and healing ligaments to repetitive low loads (creep tested at 2.2, 4.1, and 7.1 MPa, respectively. Creep test stresses were a constant 30% of the failure strength of non-immobilized scars at the different healing intervals. Normal MCLs were creep tested at 4.1 and 7.1 MPa (n=13). The cyclic modulus of the non-immobilized scars was less than that of normal ligaments. The percent increase in modulus during cycling was greater for scars than for normal ligaments, likely related to increased viscous dissipation or material inferiorities in scars. Furthermore, immobilization significantly decreased the ability of scars to resist strain, with a majority of immobilized scars failing during repetitive loading. Such failures were preceded by a reduction in cyclic modulus indicating damage to the healing ligaments that was predictive of eventual total failure. The implications of this study are that joints with healing ligaments may have increased strain in joint structures while they are under stress, potentially leading to joint instability. Although immobilization could be used temporarily to maintain joint stability, remobilization would likely lead to total failure of the healing ligament. PMID:12798073

Thornton, G M; Shrive, N G; Frank, C B

2003-07-01

343

Enfermedad periodontal necrosante: Conducta odontológica / Necrotizing periodontal disease: Dental behavior  

Scientific Electronic Library Online (English)

Full Text Available SciELO Venezuela | Language: Spanish Abstract in spanish El cuidado periodontal es, en esencia, labor del odontólogo y éste no puede pasar por alto la responsabilidad de proveer atención a todo paciente. La incidencia excesivamente elevada de problemas periodontales entre la población, dificulta que un número reducido de especialistas pueda enfrentarlos. [...] En la cavidad bucal se pueden producir variedades de enfermedades de etiología diferente en este caso infeccioso bacteriano, por ello es muy importante que el odontólogo identifique y conozca las consecuencias ocasionadas si no se previenen o tratan a tiempo, así como las complicaciones. El término enfermedad periodontal necrosante se emplea como denominador común de la gingivitis, periodontitis y estomatitis necrosante, las cuales son un conjunto de enfermedades inflamatorias, dolorosas y destructivas que afecta primariamente la encía marginal como la papilar y con menor frecuencia, la encía adherida, llegando afectar el hueso alveolar. Suele encontrarse en cavidades bucales sanas o sobre añadido a una enfermedad gingival o periodontal, aparece en un diente, o un grupo de ellos, o abarcar toda la cavidad bucal y presentarse en individuos, con buena o deficiente higiene bucal. Es anómalo en edéntulos, pero a veces, se producen lesiones esféricas aisladas en el paladar blando. El propósito de esta revisión es describir las diferentes presentaciones clínicas de dicha patología, su etiología, diagnósticos diferenciales y diferentes métodos de tratamiento, además de la interconsulta con diferentes áreas, para valorar sus complicaciones y cuidados postoperatorios. Para ello se realizó basado en los lineamientos de la investigación descriptiva documental, una revisión de la literatura nacional e internacional Abstract in english The premise is that periodontal problems are treated by general dentists and they should not skip the responsibility to treat all of their patients. The excessive incidence of periodontal problems in the population makes it difficult to treat them by a specific number of specialists. There is a vari [...] ety of diseases from various infectious etiology that take place in the mouth, it is essential that dentists know the importance of diagnosing, and also be aware of the consequences if they are not treated on time. The term necrotizing periodontal disease is used as common denominator of gingivitis, periodontal and necrotizing estomatitis, which are a group of dangerous, inflammatory and destructive diseases that affect mainly the marginal gum like the papilar and less frequently the adhesive gum affecting the alveolar bone. They can be found in healthy mouths or additional to a periodontal or gingival disease, in a tooth or in a group of them, or in the whole mouth or in individuals with good or poor mouth hygiene. It is not usual to find them as edentulous but sometimes isolated spheric injuries in the soft palate. The purpose of this report is to describe the different clinic presentation, etiology and pathogenesis, epidemiology diagnose, differentials, treatment, prognosis, complications and post surgery care. That’s why a revision of the national and international literature was made based upon on documentary descriptive research techniques

Yuni J, Salinas M; Ronald E, Millán I.

2009-12-01

344

Imaging of the anterior cruciate ligament  

Directory of Open Access Journals (Sweden)

Full Text Available The anterior cruciate ligament (ACL is an important structure in maintaining the normal biomechanics of the knee and is the most commonly injured knee ligament. However, the oblique course of the ACL within the intercondylar fossa limits the visualization and assessment of the pathology of the ligament. This pictorial essay provides a comprehensive and illustrative review of the anatomy and biomechanics as well as updated information on different modalities of radiological investigation of ACL, particularly magnetic resonance imaging.

Wing Hung Alex Ng

2011-01-01

345

Pediatric anterior cruciate ligament reconstruction  

OpenAIRE

An increasing number of anterior cruciate ligament (ACL) injuries are seen in children now than in the past due to increased sports participation. The natural history of ACL deficient knees in active individuals, particularly in children is poor. Surgical management of ACL deficiency in children is complex due to the potential risk of injury to the physis and growth disturbance. Delaying ACL reconstruction until maturity is possible but risks instability episodes and intra-articular damage. S...

Mcconkey, Mark O.; Bonasia, Davide Edoardo; Amendola, Annunziato

2011-01-01

346

Pulp Revascularization of Immature Permanent Teeth: A Review of the Literature and a Proposal of a New Clinical Protocol.  

Science.gov (United States)

Tissue engineering is a growing field. In the near future, it will probably be possible to generate a complete vital tooth from a single stem cell. Pulp revascularization is dependent on the ability of residual pulp and apical and periodontal stem cells to differentiate. These cells have the ability to generate a highly vascularized and a conjunctive rich living tissue. This one is able to colonize the available pulp space. Revascularization is a new treatment method for immature necrotic permanent teeth. Up to now, apexification procedures were applied for these teeth, using calcium dihydroxide or MTA to produce an artificial apical barrier. However, the pulp revascularization allows the stimulation of the apical development and the root maturation of immature teeth. Two pulp revascularization techniques are used in the literature, one using calcium dihydroxide and the second using a triple antibiotic paste. Based on these two different pulp revascularization protocols, which obtain the desired therapeutic success, the literature will be reviewed and analyzed according to the relevance of their choice of materials. Based on the literature, we propose a new relevant protocol and a new mixture of antibiotics. PMID:25383384

Namour, Mélanie; Theys, Stephanie

2014-01-01

347

Tip II diyabetli periodontitis hastalar?nda periodontal tedavinin a??z kokusuna etkisi  

OpenAIRE

The aim of this study was to evaluate the effect of Phase 1 periodontal therapy on oral malodour levels in Type 2 DM patients with chronic periodontitis. Out of fifty patients, 24 females and 26 males, were included in the study. Thirty of them were in test group (TG) and the rest were in control group (CG). Test group received Phase 1 periodontal therapy, however, control group received neither periodontal therapy nor oral hygiene instructions. Clinical evaluation of the patients co...

Hafize Sezer; Ismail Marakoglu; Vildan Bostanci; Tamer Ataoglu; Aysun Akpinar

2011-01-01

348

Evaluating the Effect of Periodontal Dressing on Wound Healing after Periodontal Flap Surgery  

OpenAIRE

Introduction & Objective: After periodontal surgery the surgical site is usually covered with periodontal pack. It is suggested that dressings can reduce the rate of infection, bleeding and granulation tissue formation after surgery. In addition, they may promote tissue healing. The aim of this study is to evaluate periodontal dressing’s effect on wound healing, pain and bleeding after periodontal surgery. Materials & Methods: In this clinical trial study 33 patients attending the Hamadan d...

Bidgoli, M.; Soheilifar, S.; Jafari, M.

2014-01-01

349

Antibiotics in the management of aggressive periodontitis.  

Science.gov (United States)

Aggressive periodontitis, although not rare, is a fairly unknown condition. Little is known about its optimal management. While majority of patients with common forms of periodontal disease respond predictably well to conventional therapy (oral hygiene instructions (OHI), non-surgical debridement, surgery, and Supportive Periodontal therapy (SPT)), patients diagnosed with aggressive form of periodontal disease often do not respond predictably/favorably to conventional therapy owing to its complex multi-factorial etiology. Protocols for treating aggressive periodontitis are largely empirical. There is compelling evidence that adjunctive antibiotic treatment frequently results in more favorable clinical response than conventional therapy alone. This article mainly focuses on the role of adjunct use of pharmacological agents in improving the prognosis and treatment outcome of aggressive periodontitis patients. PMID:23066264

Prakasam, Abinaya; Elavarasu, S Sugumari; Natarajan, Ravi Kumar

2012-08-01

350

Genetic variants in periodontal health and disease  

Energy Technology Data Exchange (ETDEWEB)

Periodontitis is a complex, multifactorial disease and its susceptibility is genetically determined. The present book systematically reviews the evidence of the association between the genetic variants and periodontitis progression and/or treatment outcomes. Genetic syndromes known to be associated with periodontal disease, the candidate gene polymorphisms investigated in relation to periodontitis, the heritability of chronic and aggressive periodontitis, as well as common guidelines for association studies are described. This growing understanding of the role of genetic variation in inflammation and periodontal chronic disease presents opportunities to identify healthy persons who are at increased risk of disease and to potentially modify the trajectory of disease to prolong healthy aging. The book represents a new concept in periodontology with its pronounced focus on understanding through knowledge rather than presenting the presently valid answers. Connections between genetics and periodontology are systematically reviewed and covered in detail. (orig.)

Dumitrescu, Alexandrina L. [Tromsoe Univ. (Norway). Inst. of Clinical Dentistry; Kobayashi, Junya [Kyoto Univ. (Japan). Dept. of Genome Repair Dynamics

2010-07-01

351

Social gradients in periodontal diseases among adolescents  

DEFF Research Database (Denmark)

OBJECTIVE: To investigate the association between socioeconomic position and periodontal diseases among adolescents. METHODS: Data were obtained from 9203 Chilean high school students. Clinical examinations included direct recordings of clinical attachment level and the necrotizing ulcerative gingival lesions. Students answered a questionnaire on various dimensions of socioeconomic position. Seven periodontal outcomes were analyzed. Logistic regression analyses were used to identify socioeconomic variables associated with the periodontal outcomes. RESULTS: The occurrence of all periodontal outcomes investigated followed social gradients, and paternal income and parental education were the most influential variables. CONCLUSIONS: The study demonstrates the existence of significant social gradients in periodontal diseases already among adolescents. This is worrying, and indicates a new potential for further insight into the mechanisms of periodontal disease causation.

López, Rodrigo; Fernández, Olaya

2006-01-01

352

Histological characteristics and ultrastructure of polyethylene terephthalate LARS ligament after the reconstruction of anterior cruciate ligament in rabbits  

OpenAIRE

Polyethylene terephthalate LARS ligament were the remnant of LARS ligament used for repairing posterior cruciate ligament obtained from operation. We want to study histological characteristics and ultrastructure of polyethylene terephthalate LARS ligament after the reconstruction of anterior cruciate ligament in rabbits. Therefore, we replaced the original ACL with polyethylene terephthalate LARS ligament which was covering with the remnant of ACL in 9 rabbits (L-LARS group), while just only ...

Yu, Shao-bin; Yang, Rong-hua; Zuo, Zhong-nan; Dong, Qi-rong

2014-01-01

353

Agrupaciones familiares en periodontitis crónica / Family groupings in chronic periodontitis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Fundamento: la periodontitis crónica es una enfermedad infecciosa asociada a microorganismos Gram-negativos anaerobios. Estos microorganismos inician una serie de eventos que conducen a la pérdida de inserción periodontal y alveolar alrededor del diente. Objetivo: presentar algunos patrones clínicos [...] , radiográficos y microbiológicos comunes a cinco hermanos, dos esposos, y padre e hijo, con diagnóstico de periodontitis crónica avanzada generalizada. Método: se realizó un estudio descriptivo, donde se evaluaron cinco hermanos (grupo familiar 1), dos parejas (grupo familiar 2), y padre e hijo (grupo familiar 3). Los pacientes evaluados asistieron a las clínicas odontológicas de la Facultad de Odontología de la Universidad de Antioquia (Medellín Colombia), en busca de atención periodontal. A cada paciente se le realizó una historia clínica completa, además de un examen clínico, radiográfico y microbiológico. Resultados: todos los pacientes presentaron altos porcentajes de placa bacteriana y sangrado al sondaje, además de un gran número de bolsas periodontales con profundidades >;= 5mm y pérdida de niveles de inserción >;= a 2mm. A partir de las radigrafías, se observó pérdida ósea horizontal en la mayoría de pacientes y defectos óseos angulados en algunos de ellos. Los exámenes microbiológicos del grupo familiar 1 presentaron una mayor prevalencia de Fusobacterium nucleatum, seguido por Porphyromona gingivalis, mientras que los grupos dos y tres mostraron una frecuencia elevada de P. gingivalis. Conclusiones: las agrupaciones familiares observadas y los hallazgos de varios estudios, sugieren que la transmisión intrafamiliar de periodontopatógenos es un factor importante a tener en cuenta en la organización de las bacterias en la biopelícula. Abstract in english Background: chronic periodontitis is an infectious disease associated with anaerobic gram-negative microorganisms. These organisms begin a series of events leading to periodontal and alveolar attachment loss around the tooth. Objective: to present some clinical, x-ray and microbiological patterns co [...] mmon to five brothers, two husbands, and father and son, diagnosed with generalized severe chronic periodontitis. Method: a descriptive study was conducted, where five brothers (family group 1), two couples (family group 2), and father and son (family group 3) were evaluated in the dental clinic of the Faculty of Dentistry at the University of Antioquia (Medellin, Colombia). Each patient was carried out a complete medical history, as well as clinical, radiographic and microbiological examination. Results: all patients showed high percentages of bacterial plaque and bleeding on probing, as well as a large number of periodontal pockets with depths >;= 5 mm and attachment levels loss >;= 2 mm. Radiographically, horizontal bone loss was observed in most patients and angled bone defects in some of them. The microbiological examination of family group 1 had a higher prevalence of Fusobacterium nucleatum followed by Porphyromona gingivalis, while groups two and three showed a high frequency of P. gingivalis. Conclusions: family groupings observed and findings of several studies suggest that family transmission of pathogens is an important factor to take into account in the organization of bacteria in the biofilm.

Carlos Martín, Ardila Medina; Isabel Cristina, Guzmán.

2011-12-01

354

Regeneración de los defectos periodontales intraóseos: combinación de membranas barrera y material de relleno: evidencia preclínica y clínica Regenerative procedure for intra-bony periodontal defects: Combination of barrier membrane and filling material, clinical and preclinical evidence  

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Full Text Available La terapia periodontal regenerativa tiene como objetivo lo de restaurar los tejidos de soporte periodontal y debería resultar en la formación de nueva inserción conectiva y (nuevo cemento con nuevas fibras del ligamento periodontal insertada y nuevo hueso. Evidencia histológica en modelos preclínicos ha demostrado regeneración después de tratamiento con membranas barreras, distintos tipos de material de relleno y una combinación de los dos. De todas formas, todavía no queda claro en qué extensión la combinación de membranas barreras y material de relleno puede promover de manera adicional el proceso de regeneración en comparación con tratamientos únicos.Regenerative periodontal therapy aims to predictably restore the tooth's supporting periodontal tissues and should result in formation of a new connective tissue attachment (i.e. new cementum with inserting periodontal ligament fibres and new alveolar bone. Histologic evidence from preclinical models has demonstrated periodontal regeneration following treatment with barrier membranes, various types of grafting materials or a combination thereof. However, it is still not clear to what extenta combination of barrier membranes and grafting materials may additionally enhance the regeneration process compared with barrier membranes alone, grafting materials alone or open flap debridement.

N. Discepoli

2012-12-01

355

Regeneración de los defectos periodontales intraóseos: combinación de membranas barrera y material de relleno: evidencia preclínica y clínica / Regenerative procedure for intra-bony periodontal defects: Combination of barrier membrane and filling material, clinical and preclinical evidence  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish La terapia periodontal regenerativa tiene como objetivo lo de restaurar los tejidos de soporte periodontal y debería resultar en la formación de nueva inserción conectiva y (nuevo cemento con nuevas fibras del ligamento periodontal insertada) y nuevo hueso. Evidencia histológica en modelos preclínic [...] os ha demostrado regeneración después de tratamiento con membranas barreras, distintos tipos de material de relleno y una combinación de los dos. De todas formas, todavía no queda claro en qué extensión la combinación de membranas barreras y material de relleno puede promover de manera adicional el proceso de regeneración en comparación con tratamientos únicos. Abstract in english Regenerative periodontal therapy aims to predictably restore the tooth's supporting periodontal tissues and should result in formation of a new connective tissue attachment (i.e. new cementum with inserting periodontal ligament fibres) and new alveolar bone. Histologic evidence from preclinical mode [...] ls has demonstrated periodontal regeneration following treatment with barrier membranes, various types of grafting materials or a combination thereof. However, it is still not clear to what extenta combination of barrier membranes and grafting materials may additionally enhance the regeneration process compared with barrier membranes alone, grafting materials alone or open flap debridement.

N., Discepoli; X., Costa Berenguer; A., Bascones-Martínez.

2012-12-01

356

Root surface conditioning in periodontal treatment  

OpenAIRE

Blomlöf J Root surface conditioning, in periodontal treatment. Thesis, Karolinska Institutet. Marginal periodontal healing following both invasive and non-invasive therapiesis influenced by a large number of systemic and local factors. In ordcr to optimizehealing, a lot of effort is put into minimizing possible sources of infection bothin performing different periodontal therapies as well as during the healing period.Mechanical root surface debridement inevitably pr...

Blomlo?f, Johan

1997-01-01

357

Doença periodontal e diabete melito tipo 2  

OpenAIRE

Introdução: a doença periodontal é considerada a sexta complicação clássica do diabete melito. Estudos recentes relatam que o diabete melito e a doença periodontal apresentam uma associação bidirecional, na qual o diabete favorece o desenvolvimento da doença periodontal e esta, quando não tratada, dificulta o controle metabólico do diabete. As periodontites relacionadas a doenças sistêmicas são causadas pela placa bacteriana e também exacerbadas pela condição oral. Objetivo...

Georgia Verardi; Ana Luísa Lupatini; Joana Cristina Beltrame; Micheline Sandini Trentin; Soluete Oliveira da Silva; João Paulo de Carli; Maria Salete Sandini Linden

2009-01-01

358

Pulp and paper industry  

Energy Technology Data Exchange (ETDEWEB)

The pulp and paper industry has played a major role in Finland with regards to energy use, technological development and the economy. Finland's market share in printing and writing paper exports is 25%. Finnish companies now figure among the world's biggest pulp and paper enterprises through international consolidations. Finnish equipment manufacturers, control system suppliers and consulting engineering firms are also global players. Rapid technological changes have taken place in the unit sizes of main process equipment or whole production lines. Environmental effects have been reduced significantly, e.g. biological oxygen demand load has been reduced from 530 000 to 18 000 t/a in the last 30 years, even though the production of paper and board has tripled. Competitiveness in the future depends on the supply of raw material, energy use, environmental issues as well as on the development of information and communication technology (ICT) for transferring and storing information. The growth rate of paper products has been closely interconnected with economic development. The average annual increase in the production volume has been 2-3%, whereas the real price of products has followed a declining trend. The first indication of the effects of ICT is seen in the reduced newsprint demand in the US market. It is foreseen that the use of cut-size office papers will increase, together with individual printing. Global growth in the demand for paper products is expected to slow down but not to cease because of this development. Forest growth in Finland currently exceeds annual harvesting. Taking into account the changes in forest ownership, taxation principles and forest land protection, an increase in harvesting of 5-10% is feasible. The amount of imported wood is expected to increase also in the future. Utilisation of the available fibre supply has to be further optimised in terms of endproduct properties. Since the investment in a new production line is already in the region of 400 million euros, the development of energy efficient and environmentally friendly technologies should not increase the investment cost. Whereas the overall energy efficiency has improved in the past, the electricity intensity has increased. Turning the latter trend around poses a clear challenge for the future. The main approaches include developments in mechanical pulping, higher consistency processing along the pulp and paper production line, accurately dimensioned and controlled pumping as well as advanced process control and energy management systems. Reduction of fresh water intake and new sidestream processing techniques will improve environmental efficiency. Two scenarios are presented. In the Base scenario, the price and availability of electricity favour only a modest capacity increase, resulting in paper and board production of 15 Mt/a and electricity use of 28 TWh/a in 2030. In the Mechanical scenario, high-quality wood-containing papers dominate. The available amounts of wood species dictate the production of different paper grades. The reduction in specific electricity consumption equates to 4% from current figures. With paper and board production of 17 Mt/a, this will result in electricity consumption of 30 TWh/a. If a major breakthrough takes place in TMP production which reduces the specific electricity consumption by 30%, electricity consumption will almost remain at the present level.

Viinikainen, S.; Nousiainen, I.; Edelman, K.; Manninen, J.

2002-07-01

359

Periodontal biomechanics: finite element simulations of closing stroke and power stroke in equine cheek teeth  

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Full Text Available Abstract Background In equine dentistry periodontal diseases, especially periapical inflammation, are frequently occurring problems. Anachoresis is believed to be the most common cause for the development of such disorders. Nevertheless, there is still no substantiated explanation why settlement of pathogen microorganisms occurs in equine periodontal tissues. It is expected that excessive strains and stresses occurring in the periodontal ligament (PDL during the horse’s chewing cycle might be a predisposing factor. In this study this assumption was examined by finite element (FE analyses on virtual 3-D models of equine maxillary and mandibular cheek teeth, established on the basis of ?CT datasets. Calculations were conducted both under conditions of closing and power stroke. Results Results showed a uniform distribution of low stresses and strain energy density (SED during closing stroke, whereas during power stroke an occurrence of high stresses and SED could be observed in the PDL near the alveolar crest and in periapical regions. Conclusion The concentration of forces during power stroke in these specific areas of the PDL may cause local tissue necrosis and inflammation and thus establish a suitable environment for the settlement of microorganisms.

Cordes Vanessa

2012-07-01

360

Novel chitosan/collagen scaffold containing transforming growth factor-?1 DNA for periodontal tissue engineering  

International Nuclear Information System (INIS)

The current rapid progression in tissue engineering and local gene delivery system has enhanced our applications to periodontal tissue engineering. In this study, porous chitosan/collagen scaffolds were prepared through a freeze-drying process, and loaded with plasmid and adenoviral vector encoding human transforming growth factor-?1 (TGF-?1). These scaffolds were evaluated in vitro by analysis of microscopic structure, porosity, and cytocompatibility. Human periodontal ligament cells (HPLCs) were seeded in this scaffold, and gene transfection could be traced by green fluorescent protein (GFP). The expression of type I and type III collagen was detected with RT-PCR, and then these scaffolds were implanted subcutaneously into athymic mice. Results indicated that the pore diameter of the gene-combined scaffolds was lower than that of pure chitosan/collagen scaffold. The scaffold containing Ad-TGF-?1 exhibited the highest proliferation rate, and the expression of type I and type III collagen up-regulated in Ad-TGF-?1 scaffold. After implanted in vivo, EGFP-transfected HPLCs not only proliferated but also recruited surrounding tissue to grow in the scaffold. This study demonstrated the potential of chitosan/collagen scaffold combined Ad-TGF-?1 as a good substrate candidate in periodontal tissue engineering

361

Epidemiology and risk factors of periodontal diseases.  

Science.gov (United States)

Periodontal diseases are chronic inflammatory disorders encompassing destructive and nondestructive diseases of the periodontal supporting tissues of teeth. Gingivitis is a nondestructive disease ubiquitous in populations of children and adults globally. Aggressive periodontitis is characterized by severe and rapid loss of periodontal attachment often commencing at or after the circumpubertal age and is more prevalent among Latin Americans and subjects of African descent, and least common among Caucasians. Chronic periodontitis is a common disease and may occur in most age groups, but is most prevalent among adults and seniors world-wide. Approximately 48% of United States adults have chronic periodontitis, and similar or higher rates have been reported in other populations. Moderate and advanced periodontitis is more prevalent among the older age groups, and rates of 70% or more have been reported in certain populations. Chronic and aggressive periodontitis are multifactorial diseases caused primarily by dental plaque microorganisms, and with important modifying effects from other local and systemic factors. The study of the significance of demographic, environmental, and biologic variables is important for risk assessment and the control of periodontal diseases. PMID:15978239

Albandar, Jasim M

2005-07-01

362

Relación entre diabetes mellitus y enfermedad periodontal  

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Full Text Available La asociación entre diabetes mellitus y la enfermedad periodontal ha sido motivo de estudio durante mucho tiempo. Son varias las hipótesis que se barajan a la hora de explicar dicha relación. El propósito de este artículo es revisar los estudios publicados en la literatura periodontal hasta la fecha.The association between diabetes mellitus und Periodontal. Disease have been studied for a long time. There are several hypothesis which have tried to explain this relation. The purpose of this paper is to review the Periodontal literature up to day.

A.B. Navarro Sánchez

2002-04-01

363

ASSOCIATION OF SERUM ALBUMIN CONCENTRATION AND PERIODONTITIS  

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Full Text Available Periodontal disease is a complex, multi-factorial, chronic inflammatory disease that involves degradation of periodontal structures, including alveolar bone. Many systemic diseases and disorders have been implicated as risk indicators or risk factors in periodontal disease. Clinical and basic science research over the past several decades have led to an improved understanding and appreciation for the complexity and pathogenesis of periodontal diseases. It has been indicated that there might be an inverse relationship between periodontal disease and serum albumin concentration in elderly subjects. The present study adopted serum albumin concentration as a criterion which indicates the general health condition. The purpose of this study was to investigate the influence of periodontal disease condition on serum albumin concentration in the adult population. Our study showed a significant inverse association between the loss of attachment and the serum albumin concentration and this association was more pronounced in periodontitis group. The level of serum albumin was comparatively less in periodontitis patients when compared to the healthy controls which were of no much statistical significance. As the loss of attachment increased the serum albumin concentration decreased in the test group. But the cause to effect relationship of periodontal disease and serum albumin concentration is still unknown. This relationship might be explained by two conceivable possibilities, namely the influence of nutritional aspect or chronic disease aspect.

Ramesh Amitha

2012-11-01

364

The association of periodontitis and metabolic syndrome.  

Science.gov (United States)

Metabolic syndrome (MS) is a condition, which constitutes a group of risk factors that occur together and increase the risk for Coronary Artery Disease, Stroke and type 2 diabetes mellitus. This disorder is found prevalent in the industrialized societies of the world in epidemic proportions. Periodontitis is an oral disease of microbial origin characterized by loss of attachment apparatus of tooth, resulting in edentulism if untreated. Periodontitis has been attributed to produce a low grade systemic inflammatory condition. The link of periodontitis to various systemic disorders has led to the evolution of a new branch termed as "periodontal medicine." Studies reviewed in the present paper have indicated a positive link between the MS and periodontitis and it is suggested that subjects displaying several components of MS should be submitted to periodontal examination. Present studies have displayed coherent relation between the two entities. This review will address the vicious association between MS and periodontitis, depicting the commonality of pathophysiological pathway between the two entities. Systematic reviews, meta-analysis addressing the concerned subject were screened. Whether the systematic periodontal therapy in individuals exhibiting MS has the potential to reduce the incidence of various adverse systemic complications remains a logical proposition. Further, longitudinal and controlled trials with a large population would be imperative to depict the robustness in the association between MS and periodontal disease in human subjects. PMID:24688553

Gurav, Abhijit N

2014-01-01

365

Relación entre diabetes mellitus y enfermedad periodontal  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish La asociación entre diabetes mellitus y la enfermedad periodontal ha sido motivo de estudio durante mucho tiempo. Son varias las hipótesis que se barajan a la hora de explicar dicha relación. El propósito de este artículo es revisar los estudios publicados en la literatura periodontal hasta la fecha [...] . Abstract in english The association between diabetes mellitus und Periodontal. Disease have been studied for a long time. There are several hypothesis which have tried to explain this relation. The purpose of this paper is to review the Periodontal literature up to day. [...

A.B., Navarro Sánchez; R., Faria Almeida; A., Bascones Martínez.

2002-04-01

366

Experimental formation of periodontal structure around titanium implants utilizing bone marrow mesenchymal stem cells: a pilot study.  

Science.gov (United States)

Tissue engineering in the head and neck area, presents numerous advantages. One of the most remarkable advantages is that regeneration of only a small amount of tissue can be highly beneficial to the patient, particularly in the field of periodontal tissue regeneration. For decades, successful osseointegration has provided thousands of restorations that maintain normal function. With the increasing need to utilize dental implants for growing patients and enhance their function to simulate normal tooth physiology and proprioception, there appears to be an urgent need for t concept of periodontal tissue regeneration around dental implants. In the present work, 5 goats wer used for immediate implant placement post canine teeth extraction. Each goat received 2 implan fixtures; the control side received a porous hollow root-form poly (DL-Lactide-co-Glycolide) scaf around the titanium fixture, and the experimental side received the same scaffold but seeded with autogenous bone marrow-derived mesenchymal stem cells. One animal was killed 10 days postoperatively, and the others were killed after 1 month. The results showed that on th experimental side, periodontal-like tissue with newly formed bone was demonstrated both at 1 days and after 1 month, while the control specimens showed early signs of connective tissue regeneration around the titanium fixture at 10 days, but was not shown in the 1 month specimens. I can be concluded that undifferentiated mesenchymal stem cells were capable of differentiating t provide the 3 critical tissues required for periodontal tissue regeneration: cementum, bone, a periodontal ligament. This work may provide a new approach for periodontal tissue regeneration. PMID:19579523

Marei, Mona K; Saad, Manal M; El-Ashwah, Adham M; Ei-Backly, Rania M; Al-Khodary, Mohammed A

2009-01-01

367

Genome-wide transcriptomic alterations induced by ethanol treatment in human dental pulp stem cells (DPSCs).  

Science.gov (United States)

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 seriously deteriorated teeth, gums and compromised oral health in general. It is currently unknown if alcohol exposure has any impact on adult stem cell maintenance, stem cell fate determination and plasticity, and stem cell niche environment. Here we provide detailed experimental methods, analysis and information associated with our data deposited into Gene Expression Omnibus (GEO) under GSE57255. Our data provide transcriptomic changes that are occurring by EtOH treatment of DPSCs at 24-hour and 48-hour time point. PMID:25045622

Khalid, Omar; Kim, Jeffrey J; Duan, Lewei; Hoang, Michael; Elashoff, David; Kim, Yong

2014-12-01

368

Automated Periodontal Diseases Classification System  

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Full Text Available This paper presents an efficient and innovative system for automated classification of periodontal diseases, The strength of our technique lies in the fact that it incorporates knowledge from the patients' clinical data, along with the features automatically extracted from the Haematoxylin and Eosin (H&E stained microscopic images. Our system uses image processing techniques based on color deconvolution, morphological operations, and watershed transforms for epithelium & connective tissue segmentation, nuclear segmentation, and extraction of the microscopic immunohistochemical features for the nuclei, dilated blood vessels & collagen fibers. Also, Feedforward Backpropagation Artificial Neural Networks are used for the classification process. We report 100% classification accuracy in correctly identifying the different periodontal diseases observed in our 30 samples dataset.

Aliaa A. A. Youssif

2012-01-01

369

Metabolic syndrome and periodontal disease  

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Full Text Available It is important for a dentist to be well informed and updated on the latest research on the association of oral and systemic health. Of late, the metabolic syndrome has gained importance in dental literature, and metabolic syndrome and periodontal disease have been linked. Metabolic syndrome (MeS is a group of three or more (up to five interrelated metabolic abnormalities, which increases the risk of cardiovascular morbidity and mortality. Also, both MeS and periodontal disease may be linked through a common pathophysiological pathway. Some studies have been conducted to show such an association and additional studies are required to establish this association. A dental surgeon can play a major role in evaluating patients with MeS and thus prevent the development of overt cardiovascular disease.

Bharti Vipin

2009-01-01

370

Variations in meniscofemoral ligaments at anatomical study and MR imaging  

Energy Technology Data Exchange (ETDEWEB)

Purpose To demonstrate variations in the meniscofemoral ligaments (ligaments of Wrisberg and Humphrey) at anatomical study and magnetic resonance (MR) imaging. Design Twenty-eight cadaveric knees were partially dissected for the examination of the meniscofemoral ligaments. One hundred knee MR examinations were reviewed by two experienced musculoskeletal radiologists. Proximal variations in the meniscofemoral ligaments at MR imaging were classified into three types according to the attachment site: type I, medial femoral condyle; type II, proximal half of the posterior cruciate ligament (PCL); type III, distal half of the PCL. Distal variations were classified into vertical or oblique types according to the orientation of the intermediate signal at the interface of the ligament and lateral meniscus. Results At anatomical study, six cases showed variations in the proximal insertion site of the meniscofemoral ligaments. At MR imaging 93 cases had one or more meniscofemoral ligaments, giving a total of 107 ligaments: 90 ligaments of Wrisberg and 17 ligaments of Humphrey. Forty-one ligaments of Wrisberg were type I, 28 type II, 19 type III, and with two indeterminate type, while 6 ligaments of Humphrey were type I and the remaining 11 were indeterminate. Seven cases showed no meniscofemoral ligament. Of the 107 meniscofemoral ligaments, the distal insertion orientation was of vertical type in 10 ligaments, oblique type in 70 and unidentified in 27. Conclusion An understanding of the high incidence of meniscofemoral ligament variations may help in the interpretation of knee MR studies. (orig.) With 7 figs., 1 tab., 16 refs.

Cho, J.M.; Suh, J.S. [Department of Diagnostic Radiology, Yonsei University College of Medicine, Seoul (Korea, Republic of); Na, J.B. [Department of Diagnostic Radiology, Kyungsang National University, College of Medicine, Jinju (Korea, Republic of); Cho, J.H. [Department of Diagnostic Radiology, Ajou University College of Medicine, Suwon (Korea, Republic of); Kim, Y.; Yoo, W.K. [Department of Rehabilitation, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, H.Y.; Chung, I.H. [Department of Anatomy, Yonsei University College of Medicine, Seoul (Korea, Republic of)

1999-04-01

371

Variations in meniscofemoral ligaments at anatomical study and MR imaging  

International Nuclear Information System (INIS)

Purpose To demonstrate variations in the meniscofemoral ligaments (ligaments of Wrisberg and Humphrey) at anatomical study and magnetic resonance (MR) imaging. Design Twenty-eight cadaveric knees were partially dissected for the examination of the meniscofemoral ligaments. One hundred knee MR examinations were reviewed by two experienced musculoskeletal radiologists. Proximal variations in the meniscofemoral ligaments at MR imaging were classified into three types according to the attachment site: type I, medial femoral condyle; type II, proximal half of the posterior cruciate ligament (PCL); type III, distal half of the PCL. Distal variations were classified into vertical or oblique types according to the orientation of the intermediate signal at the interface of the ligament and lateral meniscus. Results At anatomical study, six cases showed variations in the proximal insertion site of the meniscofemoral ligaments. At MR imaging 93 cases had one or more meniscofemoral ligaments, giving a total of 107 ligaments: 90 ligaments of Wrisberg and 17 ligaments of Humphrey. Forty-one ligaments of Wrisberg were type I, 28 type II, 19 type III, and with two indeterminate type, while 6 ligaments of Humphrey were type I and the remaining 11 were indeterminate. Seven cases showed no meniscofemoral ligament. Of the 107 meniscofemoral ligaments, the distal insertion orientation was of vertical type in 10 ligaments, oblique type in 70 and unidentified in 27. Conclusion An understandidentified in 27. Conclusion An understanding of the high incidence of meniscofemoral ligament variations may help in the interpretation of knee MR studies. (orig.)

372

A REVIEW ON EFFECTIVE APPLICATION OF AN ENAMEL MATRIX DERIVATIVE (EMDOGAIN® FOR PERIODONTAL SURGERY IN THE PRESENCE OF BLOOD  

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Full Text Available Reconstructive periodontal surgery aims at predictably restoring tooth’s supporting structure lost due to perio? dontal disease or trauma. One such modality, which has been demonstrate to promote periodontal regeneration, is an enamel matrix derivative (EMD, consisting of a formu? lation of amelogenin proteins from developing porcine enamel. This review article provides a brief update on the effects of blood interaction, occurring during periodontal surgery, on the effectiveness of EMD adsorption on the root surfaces and its implications for periodontal recon? structive surgery.The clinical use of an enamel matrix derivative (EMD has been successfully proved in periodontal surgery, as promoting regeneration of periodontal tissues including new cementum, periodontal ligament (PDL and alveolar bone [1]. Despite its widespread use, only recently has the effect of blood, occurring during periodontal surgery, been evaluated for contamination of the effectiveness of EMD adsorption onto root surfaces. The aim of this review arti? cle is to provide the clinician a summary of findings from in vitro experiments testing the effects of EMD adsorption onto root surfaces in the presence and absence of blood and its effect on PDL cell behavior [2]. Until recently, the extent to which bleeding occurring during periodontal sur? gery affects the adsorption of EMD onto root surfaces could not be established.In summary, the teeth extracted for orthodontic reasons were subject to ex vivo scaling and root planing and expo? sed to 6 clinically relevant scenarios, as illustrated in figure 1. EMD application is usually performed following root surface conditioning with 24% EDTA. Findings from high resolution scanning electron microscopy (SEM demons? trated that the proteins found in blood (mainly albumin were able to compete with those found in EMD (Figure 2, reducing the effectiveness of EMD thereafter. No apparent effect of conditioning the surface with 24% EDTA was observed.Clinically ,theeffectofEDT Arootconditioning on the healing of intrabone defects treated with an enamel matrix protein derivative has been tested, however no sta? tistical clinical differences were observed between open flat debridement (OFD, followed by root surface conditioning with EDTA, and application of EMD versus that of OFD + EMD alone [3,4].

Oana M. CALUSERU

2013-06-01

373

Automated Periodontal Diseases Classification System  

OpenAIRE

This paper presents an efficient and innovative system for automated classification of periodontal diseases, The strength of our technique lies in the fact that it incorporates knowledge from the patients' clinical data, along with the features automatically extracted from the Haematoxylin and Eosin (H&E) stained microscopic images. Our system uses image processing techniques based on color deconvolution, morphological operations, and watershed transforms for epithelium & connective tissue se...

Youssif, Aliaa A. A.; Abeer Saad Gawish,; Mohammed Elsaid Moussa

2012-01-01

374

Diagnóstico educativo y capacitación periodontal  

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Full Text Available Se realizó una investigación en individuos de ambos sexos, mayores de 14 años de edad y pertenecientes al área de salud que atiende la Facultad de Estomatología del ISCM-H, con el objetivo de evaluar un método de diagnóstico y capacitación en salud periodontal. La muestra fue seleccionada al azar y se dividió en 2 grupos (estudio y control. A cada uno de los individuos escogidos se les realizó una encuesta inicial para determinar conocimientos relativos a la enfermedad periodontal (diagnóstico educativo, y se determinó que eran semejantes, pues no se encontraron diferencias estadísticamente significativas entre ambas. El grupo de estudio se sometió al método educativo propuesto y los resultados de conocimientos obtenidos después de este mostraron diferencias significativas en relación con el diagnóstico educativo. Ambos grupos, que a su inicio eran semejantes, volvieron a encuestarse al año, y se observó que el grupo de estudio seguía manteniendo mejores resultados.A research was made in individuals over 14 of both sexes from the health area receiving attention at the Dental Faculty of the Higher Institute of Medical Sciences of Havana City aimed at evaluating a method of diagnosis and upgrading in periodontal health. The sample was selected at random and it was divided into 2 groups (study and control. An inititial survey was done to every selected individual to determine his knowledge of periodontal disease (diagnostic-educative and it was found that they were similar, since no statistically significant differences were observed between them. The study group was applied the proposed educative method and the results obtained showed marked differences in relation to the educative diagnosis. Both groups that were similar at the beginning were surveyed again a year later and the study group still had better results.

Odalys V Campaña Proenza

2002-12-01

375

Health Literacy in Periodontal Patients  

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Full Text Available Introduction: health literacy is a fundamental part of the healing promotion. The aim of this study was to evaluate periodontal health literacy among patients. Materials and methods: 296 patients attending periodontal clinic who were above 16 years old participated in this study. Gathering data was based on screening questions on a 5-point Likert scale. After completion questionnaire, data was analyzed by Mann-Whitney and Kruskal-Wallis test. Based on the scores of questions, patients were classified as weak, medium and good health literacy. Result: This study showed significant difference in health literacy between age and education groups (P value = 0.015, P value = 0.003, while there was no significant difference between male and female (P value = 0.54. It was also revealed that patients who had been exposed to oral health education had higher health literacy levels ( P value < 0.0001, P value = 0.001. Conclusion: The results of this study showed patients less than 20 years and over 50 years old had poorer heath literacy in relation of periodontal heath, also, patients with higher educational level have higher health literacy.

Ahmad Haerian

2013-04-01

376

Diabetes y su impacto en el territorio periodontal Diabetes and its impact in periodontal tissues  

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Full Text Available Diabetes y enfermedad periodontal corresponden probablemente al mejor ejemplo de cómo una enfermedad sistémica puede tener un efecto en el territorio periodontal. Si bien esta asociación ha sido extensamente estudiada, muchas de las asociaciones propuestas presentan contradicciones. En la presente revisión de la literatura se analizan los siguientes tópicos relevantes para la práctica clínica en periodoncia e implantología: i Identificación de enfermedad periodontal severa y su capacidad para diagnosticar casos de diabetes; ii Efectos de la diabetes sobre la enfermedad periodontal; iii Efectos de la diabetes sobre la reparación periodontal y periimplantaria; iv Efecto del tratamiento periodontal sobre el control metabólico de la diabetes.Diabetes and periodontal disease correspond to conditions that probably exemplify how a systemic disease may have a strong impact in the periodontium. Although this association has been studied for several years, many of these studies still show contradictory results. The present review analyses the following questions relevant for the clinician in the fields of periodontology: i Value of the diagnosis of severe periodontitis and its capacity to identify previously un-diagnosed cases of diabetes; ii Effects of diabetes on periodontal disease; iii Effects of diabetes on periodontal and peri-implant tissue repair and regeneration and; iv Effect of periodontal therapy on the metabolic control of diabetes.

P Smith

2012-08-01

377

Diabetes y su impacto en el territorio periodontal / Diabetes and its impact in periodontal tissues  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish Diabetes y enfermedad periodontal corresponden probablemente al mejor ejemplo de cómo una enfermedad sistémica puede tener un efecto en el territorio periodontal. Si bien esta asociación ha sido extensamente estudiada, muchas de las asociaciones propuestas presentan contradicciones. En la presente r [...] evisión de la literatura se analizan los siguientes tópicos relevantes para la práctica clínica en periodoncia e implantología: i) Identificación de enfermedad periodontal severa y su capacidad para diagnosticar casos de diabetes; ii) Efectos de la diabetes sobre la enfermedad periodontal; iii) Efectos de la diabetes sobre la reparación periodontal y periimplantaria; iv) Efecto del tratamiento periodontal sobre el control metabólico de la diabetes. Abstract in english Diabetes a