WorldWideScience
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Immunohistochemical localization of SNARE proteins in dental pulp and periodontal ligament of the rat incisor.  

Science.gov (United States)

Distribution of three soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) proteins, syntaxin-1, synaptosomal-associated protein of 25 kDa (SNAP-25), and vesicle-associated membrane protein-2 (VAMP-2), was examined in dental pulp and periodontal ligament of the rat incisor. In the trigeminal ganglion, syntaxin-1 and SNAP-25 immunoreactivity was predominately detected in medium- to large-sized neurons. Most syntaxin-1 immunoreactive neurons expressed SNAP-25. In contrast, VAMP-2 was localized in small- to medium-sized neurons and in slender-shaped cells surrounding SNAP-25-immunopositive neurons. When the inferior alveolar nerve, one of the mandibular nerve branches innervating the dental pulp and periodontal ligament, was ligated, SNARE proteins accumulated at the site proximal to the ligation. In the incisor dental pulp, all nerve fibers displayed immunoreactivity for syntaxin-1, SNAP-25, and VAMP-2. In the periodontal ligament of the incisor, almost all nerve fibers displayed both syntaxin-1 and SNAP-25 immunoreactivity, but lacked VAMP-2 immunoreactivity. SNAP-25 protein expression was localized around the vesicle membranes at the axon terminal of the periodontal mechanoreceptors. These present data suggest that these three SNARE proteins are synthesized at the trigeminal ganglion, transported centrally and peripherally, and expressed in sensory endings where apparent synapses are not present. Because those proteins participate in docking and exocytosis of synapse vesicles in the central nervous system, they might also contribute to vesicle exocytosis at receptive fields where apparent synapses are not present. PMID:20186959

Honma, Shiho; Taki, Kunitaka; Lei, Shi; Niwa, Hitoshi; Wakisaka, Satoshi

2010-06-01

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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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Functional differences in mesenchymal stromal cells from human dental pulp and periodontal ligament.  

Science.gov (United States)

Clinically reported reparative benefits of mesenchymal stromal cells (MSCs) are majorly attributed to strong immune-modulatory abilities not exactly shared by fibroblasts. However, MSCs remain heterogeneous populations, with unique tissue-specific subsets, and lack of clear-cut assays defining therapeutic stromal subsets adds further ambiguity to the field. In this context, in-depth evaluation of cellular characteristics of MSCs from proximal oro-facial tissues: dental pulp (DPSCs) and periodontal ligament (PDLSCs) from identical donors provides an opportunity to evaluate exclusive niche-specific influences on multipotency and immune-modulation. Exhaustive cell surface profiling of DPSCs and PDLSCs indicated key differences in expression of mesenchymal (CD105) and pluripotent/multipotent stem cell-associated cell surface antigens: SSEA4, CD117, CD123 and CD29. DPSCs and PDLSCs exhibited strong chondrogenic potential, but only DPSCs exhibited adipogenic and osteogenic propensities. PDLSCs expressed immuno-stimulatory/immune-adhesive ligands like HLA-DR and CD50, upon priming with IFN?, unlike DPSCs, indicating differential response patterns to pro-inflammatory cytokines. Both DPSCs and PDLSCs were hypo-immunogenic and did not elicit robust allogeneic responses despite exposure to IFN? or TNF?. Interestingly, only DPSCs attenuated mitogen-induced lympho-proliferative responses and priming with either IFN? or TNF? enhanced immuno-modulation capacity. In contrast, primed or unprimed PDLSCs lacked the ability to suppress polyclonal T cell blast responses. This study indicates that stromal cells from even topographically related tissues do not necessarily share identical MSC properties and emphasizes the need for a thorough functional testing of MSCs from diverse sources with respect to multipotency, immune parameters and response to pro-inflammatory cytokines before translational usage. PMID:24393246

Vasandan, Anoop Babu; Shankar, Shilpa Rani; Prasad, Priya; Sowmya Jahnavi, Vulugundam; Bhonde, Ramesh Ramachandra; Jyothi Prasanna, Susarla

2014-02-01

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Functional differences in mesenchymal stromal cells from human dental pulp and periodontal ligament  

OpenAIRE

Clinically reported reparative benefits of mesenchymal stromal cells (MSCs) are majorly attributed to strong immune-modulatory abilities not exactly shared by fibroblasts. However, MSCs remain heterogeneous populations, with unique tissue-specific subsets, and lack of clear-cut assays defining therapeutic stromal subsets adds further ambiguity to the field. In this context, in-depth evaluation of cellular characteristics of MSCs from proximal oro-facial tissues: dental pulp (DPSCs) and period...

Vasandan, Anoop Babu; Shankar, Shilpa Rani; Prasad, Priya; Sowmya Jahnavi, Vulugundam; Bhonde, Ramesh Ramachandra; Jyothi Prasanna, Susarla

2014-01-01

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Successful periodontal ligament regeneration by periodontal progenitor preseeding on natural tooth root surfaces.  

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The regeneration of lost periodontal ligament (PDL) and alveolar bone is the purpose of periodontal tissue engineering. The goal of the present study was to assess the suitability of 3 odontogenic progenitor populations from dental pulp, PDL, and dental follicle for periodontal regeneration when exposed to natural and synthetic apatite surface topographies. We demonstrated that PDL progenitors featured higher levels of periostin and scleraxis expression, increased adipogenic and osteogenic differentiation potential, and pronounced elongated cell shapes on barren root chips when compared with dental pulp and dental follicle cells. When evaluating the effect of surface characteristics on PDL progenitors, natural root surfaces resulted in elongated PDL cell shapes, whereas PDL progenitors on synthetic apatite surfaces were rounded or polygonal. In addition, surface coatings affected PDL progenitor gene expression profiles: collagen I coatings enhanced alkaline phosphatase and osteocalcin expression levels and laminin-1 coatings increased epidermal growth factor (EGF), nestin, cadherin 1, and keratin 8 expression. PDL progenitors seeded on natural tooth root surfaces in organ culture formed new periodontal fibers after 3 weeks of culture. Finally, replantation of PDL progenitor-seeded tooth roots into rat alveolar bone sockets resulted in the complete formation of a new PDL and stable reattachment of teeth over a 6-month period. Together, these findings indicate that periodontal progenitor cell type as well as mineral surface topography and molecular environment play crucial roles in the regeneration of true periodontal anchorage. PMID:21250830

Dangaria, Smit Jayant; Ito, Yoshihiro; Luan, Xianghong; Diekwisch, Thomas G H

2011-10-01

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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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Role of periodontal ligament fibroblasts in osteoclastogenesis: a review.  

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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

2015-04-01

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Endocannabinoids and Inflammatory Response in Periodontal Ligament Cells  

OpenAIRE

Endocannabinoids are associated with multiple regulatory functions in several tissues. The main endocannabinoids, anandamide (AEA) and 2-arachidonylglycerol (2-AG), have been detected in the gingival crevicular fluid of periodontitis patients, but the association between periodontal disease or human periodontal ligament cells (hPdLCs) and endocannabinoids still remain unclear. The aim of the present study was to examine the effects of AEA and 2-AG on the proliferation/viability and cytokine/c...

O?zdemir, Burcu; Shi, Bin; Bantleon, Hans Peter; Moritz, Andreas; Rausch-fan, Xiaohui; Andrukhov, Oleh

2014-01-01

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Regeneration of bone and periodontal ligament induced by recombinant amelogenin after periodontitis.  

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Regeneration of mineralized tissues affected by chronic diseases comprises a major scientific and clinical challenge. Periodontitis, one such prevalent disease, involves destruction of the tooth-supporting tissues, alveolar bone, periodontal-ligament and cementum, often leading to tooth loss. In 1997, it became clear that, in addition to their function in enamel formation, the hydrophobic ectodermal enamel matrix proteins (EMPs) play a role in the regeneration of these periodontal tissues. The epithelial EMPs are a heterogeneous mixture of polypeptides encoded by several genes. It was not clear, however, which of these many EMPs induces the regeneration and what mechanisms are involved. Here we show that a single recombinant human amelogenin protein (rHAM(+)), induced in vivo regeneration of all tooth-supporting tissues after creation of experimental periodontitis in a dog model. To further understand the regeneration process, amelogenin expression was detected in normal and regenerating cells of the alveolar bone (osteocytes, osteoblasts and osteoclasts), periodontal ligament, cementum and in bone marrow stromal cells. Amelogenin expression was highest in areas of high bone turnover and activity. Further studies showed that during the first 2 weeks after application, rHAM(+) induced, directly or indirectly, significant recruitment of mesenchymal progenitor cells, which later differentiated to form the regenerated periodontal tissues. The ability of a single protein to bring about regeneration of all periodontal tissues, in the correct spatio-temporal order, through recruitment of mesenchymal progenitor cells, could pave the way for development of new therapeutic devices for treatment of periodontal, bone and ligament diseases based on rHAM(+). PMID:19228267

Haze, Amir; Taylor, Angela L; Haegewald, Stefan; Leiser, Yoav; Shay, Boaz; Rosenfeld, Eli; Gruenbaum-Cohen, Yael; Dafni, Leah; Zimmermann, Bernd; Heikinheimo, Kristiina; Gibson, Carolyn W; Fisher, Larry W; Young, Marian F; Blumenfeld, Anat; Bernimoulin, Jean P; Deutsch, Dan

2009-06-01

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Histopathological Effect of Advanced Periodontal Disease on the Dental Pulp  

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Full Text Available Statement of Problem: Many authors have claimed that pulpal inflammation may occur following periodontal diseases. Appropriate diagnosis of different lesions that have affected the dental pulp or periodontium is critical for prevention of unnecessary or harmful treatments; this must be taken into account before treatment.Purpose: The purpose of this study was histological evaluation of the pulp in the teeth with advanced periodontitis.Materials and Method: 30 permanent single teeth root that had advanced periodontitis with attachment loss ? 5 mm at least in one surface were used. The teeth were not maintainable and did not have caries, restoration and any sign of primary trauma from occlusion and did not receive any periodontal professional treatment in the past 6 months with no background of trauma. After clinical and radiographical examination and confirmation of the existence of advanced periodontitis, the teeth were extracted. Then cracks were created in the teeth by special clips. After fixation of the teeth in 10% formalin solution and decalcification by 10% nitric acid, the sections were prepared and stained by hematoxylin and eosin and then evaluated from histological perspectives. The data were analyzed by Spearman correlation coefficient ANOVA, t-test and Kruskal wallis tests.Results: In this survey, we did not find any significant correlation between clinical findings and histopathological situation. The relationship between clinical attachment loss and pulp diagnosis was statistically significant ( p =0.043. Also there was a statistically significant relationship between clinical attachment loss and calcification in the pulp ( p =0.014.Conclusion: According to the result of this research, it seems that periodontal condition affects the pulpal condition and it should be considered in future treatments on these teeth.

Seyedmajidi M.

2011-08-01

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Recession of periodontal ligament as an indicator of age.  

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The recession of the periodontal ligament has been used as one of several indicators of age in methods for age estimation. In a sample of 1000 teeth the relationship between age and periodontal recession was studied for each type of tooth. Only a weak correlation was found, the least weak being for premolars. The mean of the periodontal recession measured in mm showed approximately the same correlation as when assessed by scoring systems. Logarithmic transformation of the mean of the recession resulted in a stronger correlation with age. The use of tooth age rather than individual age did not have the same effect. Periodontal recession tended to be more rapid in males than in females. The reason for extraction was not found to be significantly correlated with periodontal recession. In conclusion, periodontal recession was not sufficiently accurate to be used as a sole indicator of age. However, in multiple regression methods for age estimation it might contribute significantly to the age equation, especially for premolars. PMID:1342054

Solheim, T

1992-12-01

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ELECTRIC PULP TEST OF TEETH WITH PERIODONTAL DISEASE.  

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Full Text Available Purpose: The aim of the research is to investigate the change in pulp vitality of teeth with periodontal disease using electric pulp tester (EPT. Methods: Subjected to observation were 108 patients with chronic periodontitis. Vitality of 805 teeth with periodontal pocket depth greater than 4 mm was studied by EPT. The research was conducted with EPT "Yonovit ". Results: The highest percentage of surveyed teeth (68.4% respond to the norm when they are tested with EPT – values between 3 ?A and 10 ?A . Teeth that respond to EPT with values ??below 3 ?A and between 35-100 ?A are relatively equal - respectively 4.3% and 3.3%. With increased threshold of irritation – 10-35 ?A react 23.4% of teeth. Small number of teeth have threshold of irritation over 100 ?A - 0.6%. Conclusion: The value of EPT among periodontal damaged teeth depends on many factors - patient's age, extent of periodontal affect, group affiliation of teeth, etc.

Tsonko Uzunov

2014-10-01

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The structure and function of periodontal ligament cells in acellular cementum in rat molars.  

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To elucidate the structure and function of periodontal ligament cells at the periodontal ligament-cementum interface in advanced acellular cementogenesis, the cervical regions of molars in rats aged 6 weeks were observed by light and electron microscopy. The light and transmission electron microscopy showed the periodontal ligament cells to be elongated between dense, well-developed principal fibers. The transmission and scanning electron microscopy showed that these cells extended wing-like projections from the lateral surface, forming cylindrical compartments surrounding the principal fibers. In addition, finger-like projections extended toward the cementum from the cementum-facing ends. The main results suggest the following: at the periodontal ligament-cementum interface, the periodontal ligament cells maintain the architecture of the principal fibers by means of extracellular compartments. The arrangement of finger-like projections results in the formation of acellular cementum containing only Sharpey's fibers as a fibrous component. PMID:9862031

Yamamoto, T; Domon, T; Takahashi, S; Islam, N; Suzuki, R; Wakita, M

1998-12-01

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

OpenAIRE

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 induced 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 PD...

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

2014-01-01

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

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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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The Pro-Apoptotic and Pro-Inflammatory Effects of Calprotectin on Human Periodontal Ligament Cells  

OpenAIRE

Calprotectin, a heterodimer of S100A8 and S100A9 subunits, is associated with inflammatory disorders such as rheumatoid arthritis and cystic fibrosis. Although calprotectin levels are increased significantly in the gingival crevicular fluid (GCF) of periodontitis patients, its effects on periodontal ligament cells (PDLCs) remain largely unknown. The aim of this study was to evaluate calprotectin levels in the GCF of generalized aggressive periodontitis (AgP) patients and to investigate the ef...

Zheng, Yunfei; Hou, Jianxia; Peng, Lei; Zhang, Xin; Jia, Lingfei; Wang, Xian E.; Wei, Shicheng; Meng, Huanxin

2014-01-01

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

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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

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Dynamic shear properties of the porcine molar periodontal ligament.  

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The role of the periodontal ligament (PDL) is to support the tooth during function and resist external forces applied to it. The dominant vertical component of these forces is associated with shear in the PDL. Little information, however, is available on the dynamic behavior of the PDL in shear. Therefore, the present study was designed to determine the dynamic shear properties of the PDL in the porcine molar (n=10). From dissected mandibles transverse sections of the mesial root of the first molar were obtained at the apical and coronal levels and used for dynamic shear tests. Shear strain (0.5%, 1.0%, and 1.5%) was applied in superoinferior direction parallel to the root axis with a wide range of frequencies (0.01-100 Hz). The dynamic complex and storage moduli increased significantly with the loading frequency, the dynamic loss modulus showed only a small increase. The dynamic elasticity was significantly larger in the coronal region than in the apical region although the dynamic viscosity was similar in both regions. The present results suggest that non-linearities, compression/shear coupling, and intrinsic viscoelasticity affect the shear material behavior of the PDL, which might have important implications for load transmission from tooth to bone and vice versa. PMID:16949081

Tanaka, Eiji; Inubushi, Toshihiro; Takahashi, Koji; Shirakura, Maya; Sano, Ryota; Dalla-Bona, Diego A; Nakajima, Akira; van Eijden, Theo M G J; Tanne, Kazuo

2007-01-01

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Stress-relaxation and microscopic dynamics of rabbit periodontal ligament.  

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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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Xeno-free culture of human periodontal ligament stem cells.  

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The possibility of transplanting adult stem cells into damaged organs has opened a new prospective for the treatment of several human pathologies. Currently, in vitro expansion and culture of mesenchymal stem cells is founded on supplementing cell culture and differentiation medium with fetal calf serum (FCS) or fetal bovine serum (FBS) that contain numerous growth factors inducing cell attachment to plastic surfaces, proliferation, and differentiation. Mesenchymal stem cells (MSCs) cultured with medium containing FCS or FBS are unusable in the cell therapy; in fact the central issues regarding limitations in using animal sera for cell therapy is that its components are highly variable and often unknown and may trigger a xenogenic immune response, immunological reactions, and the potential transmission of prion diseases and zoonoses.Here we describe the culture system protocols for the expansion and production of human Periodontal Ligament Stem Cells (hPDLSCs) using a new xeno-free medium formulation 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. PMID:25326670

Trubiani, Oriana; Diomede, Francesca

2015-01-01

22

Mechano-regulation of collagen biosynthesis in periodontal ligament.  

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Periodontal ligament (PDL) plays critical roles in the development and maintenance of periodontium such as tooth eruption and dissipation of masticatory force. The mechanical properties of PDL are mainly derived from fibrillar type I collagen, the most abundant extracellular component. The biosynthesis of type I collagen is a long, complex process including a number of intra- and extracellular post-translational modifications. The final modification step is the formation of covalent intra- and intermolecular cross-links that provide collagen fibrils with stability and connectivity. It is now clear that collagen post-translational modifications are regulated by groups of specific enzymes and associated molecules in a tissue-specific manner; and these modifications appear to change in response to mechanical force. This review focuses on the effect of mechanical loading on collagen biosynthesis and fibrillogenesis in PDL with emphasis on the post-translational modifications of collagens, which is an important molecular aspect to understand in the field of prosthetic dentistry. PMID:25311991

Kaku, Masaru; Yamauchi, Mitsuo

2014-10-01

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Micro-Raman Spectroscopy for Monitoring Changes in Periodontal Ligaments and Gingival Crevicular Fluid  

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Micro-Raman Spectroscopy is an efficient method for analyzing biological specimens due to its sensitivity to subtle chemical and structural changes. The aim of this study was to use micro-Raman spectroscopy to analyze chemical and structural changes in periodontal ligament after orthodontic force application and in gingival crevicular fluid in presence of periodontal disease. The biopsy of periodontal ligament samples of premolars extracted for orthodontic reasons and the gingival crevicular fluid samples collected by using absorbent paper cones; were analyzed by micro-Raman spectroscopy. Changes of the secondary protein structure related to different times of orthodontic force application were reported; whereas an increase of carotene was revealed in patients affected by periodontal inflammation. PMID:25436655

Camerlingo, Carlo; d'Apuzzo, Fabrizia; Grassia, Vincenzo; Perillo, Letizia; Lepore, Maria

2014-01-01

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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

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Hypoxia augments lipopolysaccharide-induced cytokine expression in periodontal ligament cells.  

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Periodontitis is a chronic inflammatory disease characterized by the destruction of tooth supporting tissues. Hypoxia, the mainly changes of the plateau environment, can induce severe periodontitis by animal experiments. There is, however, very little information on hypoxia and lipopolysaccharide (LPS) induced cytokine expression in periodontal ligament (PDL) cells. In this article, we characterized hypoxia or P. gingivalis lipopolysaccharide (Pg LPS) induced tumor necrosis factor alpha (TNF-?), interleukin (IL)-1?, and IL-6 expression by human periodontal ligament (hPDL) cells. We found that hypoxia augmented Pg LPS induced TNF-?, IL-1?, and IL-6 expression in hPDL cells. We also demonstrated that nuclear factor kappa B pathway was involved in hypoxia augmenting Pg LPS induced cytokine expression in hPDL cells. Thus, our results suggest that the hypoxic environment may enhance the immune function of hPDL cells that is induced by Pg LPS. PMID:24609838

Jian, Congxiang; Li, Chenjun; Ren, Yu; He, Yong; Li, Yunming; Feng, Xiaodan; Zhang, Gang; Tan, Yinghui

2014-10-01

26

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

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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 < 0.05 indicated a statistically significant difference. The 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 < 0.05). In periodontal ligament cells, 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

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Migration of Periodontal Ligament Fibroblasts on Nanometric Topographical Patterns: Influence of Filopodia and Focal Adhesions on Contact Guidance  

OpenAIRE

Considered to be the “holy grail” of dentistry, regeneration of the periodontal ligament in humans remains a major clinical problem. Removal of bacterial biofilms is commonly achieved using EDTA gels or lasers. One side effect of these treatment regimens is the etching of nanotopographies on the surface of the tooth. However, the response of periodontal ligament fibroblasts to such features has received very little attention. Using laser interference lithography, we fabricated precisely d...

Hamilton, Douglas W.; Oates, Christine J.; Hasanzadeh, Abdollah; Mittler, Silvia

2010-01-01

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Effect of vitamin C administration on hydrogen peroxide-induced cytotoxicity in periodontal ligament cells.  

Science.gov (United States)

Periodontitis is a disease, which is associated with chronic inflammation and leads to significant destruction of periodontal tissues. Periodontal ligament cells (PDLCs) constitute the largest cell population in PDL tissues and a considerable body of evidence has demonstrated an association between oxidative stress and the progression of periodontitis. However, the effects on PDLCs exposed to hydrogen peroxide (H2O2) and the molecular mechanisms by which H2O2 affects periodontitis remain to be elucidated. In the present study, the potential cytotoxic effect of H2O2 and the antioxidative function of vitamin C (Vc) in PDLCs were investigated. The results demonstrated that H2O2 treatment decreased the viability of PDLCs. The decreased PDLC viability was primarily induced by apoptosis, which was evidenced by cleaved caspases-3, caspases-9 and poly (ADP-ribose) polymerase. Following optimal Vc addition, the proapoptotic effects of H2O2 were partially antagonized. Taken together, the present study demonstrated that H2O2 primarily induced the apoptosis of PDLCs and that these adverse effects were partially rescued following treatment with Vc. These results revealed how H2O2 promotes the progression of periodontitis and provide an improved understanding of the reversal effect of antioxidant treatment. Therefore, optimal Vc administration may provide a potentially effective technique in periodontal therapy. PMID:25333298

Wu, Wenlei; Yang, Nanfei; Feng, Xiujing; Sun, Tingzhe; Shen, Pingping; Sun, Weibin

2015-01-01

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Application of modified superposition model to viscoelastic behavior of periodontal ligament  

Directory of Open Access Journals (Sweden)

Full Text Available The periodontal ligament (PDL is a soft bio-logical tissue which shows a strongly nonlinear and time dependent mechanical behavior. Re-cent experiments on rabbit PDL revealed that the rate of stress relaxation is strain dependent. This nonlinear behavior of PDL cannot be de-scribed well by the separable quasi linear vis-coelasticity theory which is usually used in tis-sue biomechanics. Therefore, PDL requires a more general description which considers this nonlinearity and time dependency. The purpose of this study was to model strain dependent stress relaxation behavior of PDL using modi-fied superposition method. It is shown herein that modified superposition method describes viscoelastic nonlinearties well and shows a good compatibility with available experimental PDL data. Hence, the modified superposition model is suggested to describe periodontal ligament data, because it can suitably demon-strate both elastic nonlinearity and strain-dependent stress relaxation behavior of PDL.

B. Mirzakouchaki

2008-10-01

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

Energy Technology Data Exchange (ETDEWEB)

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

31

Gene Expression Analysis of Chronically Inflamed and Healthy Human Periodontal Ligament Cells in vivo  

OpenAIRE

Background: In the periodontium, the functions of the cell populations regarding the host-mediated tissue destruction in health and disease are not well understood. The purpose of this study was to measure the expression of genes differentially expressed in chronically inflamed periodontal ligament (PDL) cells compared to healthy PDL cells. Methods: We compared the genome-wide gene expressions of chronically inflamed and healthy PDL cells by microarray analysis, and validated the data by ...

Gersdorff, Nikolaus; Miro?, Xavier; Roediger, Matthias; Geffers, Robert; Huels, Alfons; Miosge, Nicolai; Toepfer, Tanja

2008-01-01

32

Application of modified superposition model to viscoelastic behavior of periodontal ligament  

OpenAIRE

The periodontal ligament (PDL) is a soft bio-logical tissue which shows a strongly nonlinear and time dependent mechanical behavior. Re-cent experiments on rabbit PDL revealed that the rate of stress relaxation is strain dependent. This nonlinear behavior of PDL cannot be de-scribed well by the separable quasi linear vis-coelasticity theory which is usually used in tis-sue biomechanics. Therefore, PDL requires a more general description which considers this nonlinearity and time dependency. T...

Mirzakouchaki, B.; Ghalichi, F.; Hazrati, J.

2008-01-01

33

Adhesion and Proliferation of Human Periodontal Ligament Cells on Poly(2-methoxyethyl acrylate)  

OpenAIRE

Human periodontal ligament (PDL) cells obtained from extracted teeth are a potential cell source for tissue engineering. We previously reported that poly(2-methoxyethyl acrylate) (PMEA) is highly biocompatible with human blood cells. In this study, we investigated the adhesion, morphology, and proliferation of PDL cells on PMEA and other types of polymers to design an appropriate scaffold for tissue engineering. PDL cells adhered and proliferated on all investigated polymer surfaces except fo...

Erika Kitakami; Makiko Aoki; Chikako Sato; Hiroshi Ishihata; Masaru Tanaka

2014-01-01

34

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

35

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

Scientific Electronic Library Online (English)

Full Text Available 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

36

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

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

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

38

Autologous dental pulp stem cells in periodontal regeneration: a case report.  

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Histologic findings in animal models suggest that the application of dental pulp stem cells (DPSCs) may promote periodontal regeneration in infrabony defects. This case report describes the clinical and radiographic regenerative potential of autologous DPSCs in the treatment of human noncontained intraosseous defects. A chronic periodontitis patient with one vital third molar requiring extraction was surgically treated. The third molar was extracted and used as an autologous DPSCs source to regenerate the infrabony defect on the mandibular right second premolar. At the 1-year examination, the defect was completely filled with bonelike tissue as confirmed through the reentry procedure. PMID:24956088

Aimetti, Mario; Ferrarotti, Francesco; Cricenti, Luca; Mariani, Giulia Maria; Romano, Federica

2014-01-01

39

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 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

40

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 ...

41

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  

OpenAIRE

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% ...

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

2005-01-01

42

Clinical and Histochemical Alterations of the Periodontal Ligament in Gerbils after Malocclusion Induced / Alteraciones Clínicas e Histoquímicas del Ligamento Periodontal en Gerbiles Después de Maloclusión Inducida  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in spanish El objetivo de este artículo es mostrar las alteraciones clínicas e histoquímicas del primer ligamento periodontal del lado derecho, después de la extracción del molar superior izquierdo en gerbiles {Meriones unguiculatus). Luego de dos meses, los ligamentos periodontales fueron retirados y procesad [...] os para el análisis histoquímico. Los resultados mostraron que la reacción de TRAP es capaz de evidenciar la actividad osteoclástica en la hiperfunción de la semimandíbula derecha, explicando los cambios funcionales del ligamento periodontal después de la extracción dental, siendo observada una pequeña recesión gingival y exposición radicular de los dientes sin función, en los molares inferiores izquierdos Abstract in english The aim of this article is to show the clinical and histochemical alterations of the first periodontal ligament, on the right side, after upper molars teeth extraction on the left side in gerbils. After two months, the periodontal ligaments were removed and processed for histochemical analysis. The [...] data showed that TRAP reaction was able to evidence the osteoclastic activity in the hyperfunction hemimandible, right side, explaining the functional changes in the periodontal ligament after teeth extraction, and a little gingival recession and radicular exposure of teeth without function was observed at inferior molars of the left side

Leandro Moura Leite, Naves; João Paulo Mardegan, Issa; Dimitrius Leonardo, Pitol; Sandra Yasuyo, Fukada; Miguel Ángel Sala, di Matteo; Mamie Mizusaki, Iyomasa.

2007-12-01

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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

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

Science.gov (United States)

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 induced 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%, PPDL fibroblasts. The results showed that the changes in PDL fibroblasts induced by AGE-BSA may explain how AGE-RAGE participates in and exacerbates periodontium destruction. PMID:25387669

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

2014-12-01

45

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

46

NOD1 and NOD2 stimulation triggers innate immune responses of human periodontal ligament cells  

OpenAIRE

Nod-like receptors (NLRs) are cytosolic sensors for microbial molecules. Nucleotide-binding oligomerization domain (NOD)1 and NOD2 recognize the peptidoglycan derivatives, meso-diaminopimelic acid (meso-DAP) and muramyl dipeptide (MDP), respectively, and trigger host innate immune responses. In the present study, we examined the function of NOD1 and NOD2 on innate immune responses in human periodontal ligament (PDL) cells. The gene expression of NOD1 and NOD2 was examined by RT-PCR. IL-6 and ...

Jeon, Do-in; Park, Se-ra; Ahn, Mee-young; Ahn, Sang-gun; Park, Jong-hwan; Yoon, Jung-hoon

2012-01-01

47

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.

48

The Pro-Apoptotic and Pro-Inflammatory Effects of Calprotectin on Human Periodontal Ligament Cells  

Science.gov (United States)

Calprotectin, a heterodimer of S100A8 and S100A9 subunits, is associated with inflammatory disorders such as rheumatoid arthritis and cystic fibrosis. Although calprotectin levels are increased significantly in the gingival crevicular fluid (GCF) of periodontitis patients, its effects on periodontal ligament cells (PDLCs) remain largely unknown. The aim of this study was to evaluate calprotectin levels in the GCF of generalized aggressive periodontitis (AgP) patients and to investigate the effects of recombinant human calprotectin (rhS100A8/A9) and its subunits (rhS100A8 and rhS100A9) in PDLCs. Both the concentration and amount of crevicular calprotectin were significantly higher in the AgP group compared with healthy controls. In addition, the GCF calprotectin levels were correlated positively with clinical periodontal parameters including bleeding index, probing depth, and clinical attachment loss. rhS100A8/A9 promoted cell apoptosis, whereas rhS100A8 and rhS100A9 individually exerted little effect on apoptosis in PDLCs. rhS100A9 and rhS100A8/A9 increased the activation of nuclear factor-?B (NF-?B) by promoting the nuclear translocation of p65 in PDLCs, subsequently inducing expression of the pro-inflammatory cytokines IL-6, IL-8, TNF?, and COX2. Treatment with an NF-?B inhibitor partially reversed the rhS100A9- and rhS100A8/A9-induced upregulation of the pro-inflammatory cytokines. rhS100A9, and not rhS100A8, was mainly responsible for the pro-inflammatory role of calprotectin. Collectively, our results suggest that calprotectin promotes apoptosis and the inflammatory response in PDLCs via rhS100A9. These findings might help identify novel treatments for periodontitis. PMID:25338166

Peng, Lei; Zhang, Xin; Jia, Lingfei; Wang, Xian'e; Wei, Shicheng; Meng, Huanxin

2014-01-01

49

The effect of electrospun fibre alignment on the behaviour of rat periodontal ligament cells  

Directory of Open Access Journals (Sweden)

Full Text Available It is envisioned that for the regeneration of highly organized structures, like tendon and ligaments, only aligned fibrous scaffolds can provide adequate topographic guidance to cells. In this study, a novel method to electrospin an aligned scaffold is presented. Electrospun fibres were deposited into a water bath and then the fibres were drawn to a rotating mandrel in a controlled manner. In this way, parallel and cross-aligned fibrous poly (lactide-co-glycolide (PLGA scaffolds were fabricated, which were subsequently used to study their effect on the growth behaviour of rat periodontal ligament (PDL cells. First, the scaffolds were characterized regarding mechanical properties, scaffold stability and degradation in vitro. Then, rat PDL cells were seeded and cultured on these scaffolds for up to 7 days. Randomly oriented PLGA and solvent cast plain PLGA films served as controls. Results showed that the alignment of fibres resulted in a higher tensile stress and Young’s modulus. Aligned scaffolds maintained their structural stability better compared to the controls after incubation in phosphate-buffered saline for 6 weeks. Further, cells were observed to elongate along the fibre after 3 days of culture. Proliferation and migration of PDL cells was significantly more prevalent on the aligned fibres compared to the controls. It was concluded that aligned scaffolds seem to be able to promote the organized regeneration of periodontal tissue.

S Shang

2010-04-01

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

Directory of Open Access Journals (Sweden)

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

51

Assessing qualitative changes in simulated periodontal ligament and alveolar bone using a non-contact electromagnetic vibration device.  

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The objective of this study is to investigate the ability of a non-contact electromagnetic vibration device to assess a simulated periodontal ligament and alveolar bone conditions in experimental tooth models by applying mechanical parameters (resonant frequency, elastic modulus, and coefficient of viscosity). The non-contact electromagnetic vibration device was made up of three components: vibrator, detector, and analyzer. The experimental tooth model consisted of a cylindrical rod made of polyacetal, a tissue conditioner for soft lining material, and urethane or urethane foam to simulate the tooth, periodontal ligament, and alveolar bone, respectively. The tissue conditioner was prepared by mixing various volumes of liquid with powder. Periotest values (PTVs) were also measured under the same conditions as those of the non-contact electromagnetic vibration device. All of the mechanical parameters derived from the non-contact electromagnetic vibration device significantly decreased as the proportion of liquid increased. Values for the three parameters of the urethane models were significantly larger than those of the urethane foam models. In contrast, PTVs increased significantly as the proportion of liquid increased; however, no significant difference was observed between the urethane and urethane foam models. The non-contact electromagnetic vibration device may be capable of evaluating not only periodontal ligament conditions but also bone quality. Mechanical parameters may be useful for assessing qualitative changes in the periodontal ligament and alveolar bone. PMID:21809012

Kobayashi, Chiaki; Hayashi, Makoto; Yamaoka, Masaru; Hashimoto, Kazuhiro; Kato, Takeshi; Komori, Norio; Ogiso, Bunnai

2012-08-01

52

Anabolic Properties of High Mobility Group Box Protein-1 in Human Periodontal Ligament Cells In Vitro  

Science.gov (United States)

High mobility group box protein-1 (HMGB1) is mainly recognized as a chemoattractant for macrophages in the initial phase of host response to pathogenic stimuli. However, recent findings provide evidence for anabolic properties in terms of enhanced proliferation, migration, and support of wound healing capacity of mesenchymal cells suggesting a dual role of the cytokine in the regulation of immune response and subsequent regenerative processes. Here, we examined potential anabolic effects of HMGB1 on human periodontal ligament (PDL) cells in the regulation of periodontal remodelling, for example, during orthodontic tooth movement. Preconfluent human PDL cells (hPDL) were exposed to HMGB1 protein and the influence on proliferation, migration, osteogenic differentiation, and biomineralization was determined by MTS assay, real time PCR, immunofluorescence cytochemistry, ELISA, and von Kossa staining. HMGB1 protein increased hPDL cell proliferation, migration, osteoblastic marker gene expression, and protein production as well as mineralized nodule formation significantly. The present findings support the dual character of HMGB1 with anabolic therapeutic potential that might support the reestablishment of the structural and functional integrity of the periodontium following periodontal trauma such as orthodontic tooth movement. PMID:25525297

Wolf, Michael; Lossdörfer, Stefan; Römer, Piero; Bastos Craveiro, Rogerio; Deschner, James; Jäger, Andreas

2014-01-01

53

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

Scientific Electronic Library Online (English)

Full Text Available 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

54

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

55

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

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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

56

The biomechanical role of periodontal ligament in bonded and replanted vertically fractured teeth under cyclic biting forces.  

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After teeth are replanted, there are two possible healing responses: periodontal ligament healing or ankylosis with subsequent replacement resorption. The purpose of this study was to compare the fatigue resistance of vertically fractured teeth after bonding the fragments under conditions simulating both healing modes. Thirty-two human premolars were vertically fractured and the fragments were bonded together with Super-Bond C&B. They were then randomly distributed into four groups (BP, CP, CA, BA). The BP and CP groups were used to investigate the periodontal ligament healing mode whilst the BA and CA groups simulated ankylosis. All teeth had root canal treatment performed. Metal crowns were constructed for the CP and CA groups. The BP and BA groups only had composite resin restorations in the access cavities. All specimens were subjected to a 260?N load at 4?Hz until failure of the bond or until 2×10(6) cycles had been reached if no fracture occurred. Cracks were detected by stereomicroscope imaging and also assessed via dye penetration tests. Finally, interfaces of the resin luting agent were examined by scanning electron microscope. The results confirmed that the fatigue resistance was higher in the groups with simulated periodontal ligament healing. Periodontal reattachment showed important biomechanical role in bonded and replanted vertically fractured teeth.International Journal of Oral Science advance online publication, 12 September 2014; doi:10.1038/ijos.2014.51. PMID:25214360

Zhu, Ya-Nan; Yang, Wei-Dong; Abbott, Paul V; Martin, Nicolas; Wei, Wen-Jia; Li, Jing-Jing; Chen, Zhi; Wang, Wen-Mei

2014-09-12

57

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

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Adhesion and proliferation of human periodontal ligament cells on poly(2-methoxyethyl acrylate).  

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Human periodontal ligament (PDL) cells obtained from extracted teeth are a potential cell source for tissue engineering. We previously reported that poly(2-methoxyethyl acrylate) (PMEA) is highly biocompatible with human blood cells. In this study, we investigated the adhesion, morphology, and proliferation of PDL cells on PMEA and other types of polymers to design an appropriate scaffold for tissue engineering. PDL cells adhered and proliferated on all investigated polymer surfaces except for poly(2-hydroxyethyl methacrylate) and poly[(2-methacryloyloxyethyl phosphorylcholine)-co-(n-butyl methacrylate)]. The initial adhesion of the PDL cells on PMEA was comparable with that on polyethylene terephthalate (PET). In addition, the PDL cells on PMEA spread well and exhibited proliferation behavior similar to that observed on PET. In contrast, platelets hardly adhered to PMEA. PMEA is therefore expected to be an excellent scaffold for tissue engineering and for culturing tissue-derived cells in a blood-rich environment. PMID:25165689

Kitakami, Erika; Aoki, Makiko; Sato, Chikako; Ishihata, Hiroshi; Tanaka, Masaru

2014-01-01

59

Significant Type I and Type III Collagen Production from Human Periodontal Ligament Fibroblasts in 3D Peptide Scaffolds without Extra Growth Factors  

OpenAIRE

We here report the development of two peptide scaffolds designed for periodontal ligament fibroblasts. The scaffolds consist of one of the pure self-assembling peptide scaffolds RADA16 through direct coupling to short biologically active motifs. The motifs are 2-unit RGD binding sequence PRG (PRGDSGYRGDS) and laminin cell adhesion motif PDS (PDSGR). RGD and laminin have been previously shown to promote specific biological activities including periodontal ligament fibroblasts adhesion, prolife...

Kumada, Yoshiyuki; Zhang, Shuguang

2009-01-01

60

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

61

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

Science.gov (United States)

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

62

Significant type I and type III collagen production from human periodontal ligament fibroblasts in 3D peptide scaffolds without extra growth factors.  

Science.gov (United States)

We here report the development of two peptide scaffolds designed for periodontal ligament fibroblasts. The scaffolds consist of one of the pure self-assembling peptide scaffolds RADA16 through direct coupling to short biologically active motifs. The motifs are 2-unit RGD binding sequence PRG (PRGDSGYRGDS) and laminin cell adhesion motif PDS (PDSGR). RGD and laminin have been previously shown to promote specific biological activities including periodontal ligament fibroblasts adhesion, proliferation and protein production. Compared to the pure RADA16 peptide scaffold, we here show that these designer peptide scaffolds significantly promote human periodontal ligament fibroblasts to proliferate and migrate into the scaffolds (for approximately 300 microm/two weeks). Moreover these peptide scaffolds significantly stimulated periodontal ligament fibroblasts to produce extracellular matrix proteins without using extra additional growth factors. Immunofluorescent images clearly demonstrated that the peptide scaffolds were almost completely covered with type I and type III collagens which were main protein components of periodontal ligament. Our results suggest that these designer self-assembling peptide nanofiber scaffolds may be useful for promoting wound healing and especially periodontal ligament tissue regeneration. PMID:20421985

Kumada, Yoshiyuki; Zhang, Shuguang

2010-01-01

63

Evaluation of the resolving potency of a novel reconstruction filter on periodontal ligament space with dental cone-beam CT: a quantitative phantom study  

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Diagnosis of the alveolar bone condition is important for the treatment planning of periodontal disease. Especially the determination of periodontal ligament space is the most important remark because it represents the periodontal tissue support for tooth retention. However, owing to the image blur of the current cone-beam CT (CBCT) imaging technique, the periodontal ligament space is difficult to visualize. In this study, we developed an original periodontal ligament phantom (PLP) and evaluated the image quality of simulated periodontal ligament space using a novel reconstruction filter for CBCT that emphasized high frequency component. PLP was composed from two resin blocks of different materials, the bone equivalent block and the dentine equivalent block. They were assembled to make continuously changing space from 0.0 to 1.0 millimeter that mimics periodontal ligament space. PLP was placed in water and the image was obtained by using Alphard-3030 dental cone-beam CT (Asahi Roentgen Industry Co., Ltd.). Then we reconstructed the projection data with a novel reconstruction filter. The axial images were compared with conventional reconstructed images. In novel filter reconstruction images, 0.4 millimeter of the space width was steadily detected by calculation of pixel value, on the other hand 0.6 millimeter was in conventional images. With our method, the resolving potency of conebeam CT images was improved.

Houno, Yuuki; Hishikawa, Toshimitsu; Gotoh, Ken-ichi; Naitoh, Munetaka; Ariji, Eiichiro; Kodera, Yoshie

2014-03-01

64

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

65

Cementogenic potential of multipotential mesenchymal stem cells purified from the human periodontal ligament.  

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The periodontal ligament (PDL) consists of a group of specialized connective tissue fibers embedded in the alveolar bone and cementum that are believed to contain progenitors for mineralized tissue-forming cell lineages. These progenitors may contribute to regenerative cell therapy or tissue engineering methods aimed at recovery of tissue formation and functions lost in periodontal degenerative changes. Some reports using immortal clonal cell lines of cementoblasts, which are cells containing mineralized tissue-forming cell lineages, have shown that their phenotypic alteration and gene expression are associated with mineralization. Immortal, multipotential PDL-derived cell lines may be useful biological tools for evaluating differentiation-inducing agents. In this study, we confirmed the gene expression and mineralization potential of primary and immortal human PDL cells and characterized their immunophenotype. Following incubation with mineralization induction medium containing ?-glycerophosphate, ascorbic acid, and dexamethasone, normal human PDL (Pel) cells and an immortal derivative line (Pelt) cells showed higher levels of mineralization compared with cells grown in normal growth medium. Both cell types were positive for putative surface antigens of mesenchymal cells (CD44, CD73, CD90, and CD105). They were also positive for stage-specific embryonic antigen-3, a marker of multipotential stem cells. Furthermore, PDL cells expressed cementum attachment protein and cementum protein 1 when cultured with recombinant human bone morphogenetic protein-2 or -7. The results suggest that normal and immortal human PDL cells contain multipotential mesenchymal stem cells with cementogenic potential. PMID:24399512

Torii, Daisuke; Konishi, Kiyoshi; Watanabe, Nobuyuki; Goto, Shinichi; Tsutsui, Takeki

2015-01-01

66

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

67

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

Science.gov (United States)

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

68

Cyclic tension promotes osteogenic differentiation in human periodontal ligament stem cells  

Science.gov (United States)

Orthodontic forces result in alveolar bone resorption and formation predominantly on the pressure and tension sides of the tooth roots, respectively. Human periodontal ligament stem cells (PDLSCs) have demonstrated the capacity to differentiate into osteoblasts, and they play important roles in maintaining homeostasis and regenerating periodontal tissues. However, little is known about how PDLSCs contribute to osteoblastogenesis during orthodontic tooth movement on the tension side. In this study, we applied a 12% cyclic tension force to PDLSCs cultured in osteoinductive medium. The osteogenic markers Runx2, ALP, and OCN were detected at the mRNA and protein levels at different time points using real-time PCR and western blot analyses. We discovered that the mRNA and protein levels of Runx2, ALP and OCN were significantly up-regulated after 6, 12 and 24 hours of mechanical loading on PDLSCs compared to levels in unstimulated PDLSCs (P < 0.05). This study demonstrates, for the first time, the effects of mechanical tensile strain on the osteogenic differentiation of PDLSCs, as examined with a Flexcell FX-4000T Tension Plus System. Our findings suggested that cyclic tension could promote the osteogenic differentiation of PDLSCs. Furthermore, the effects of orthodontic force on alveolar bone remodeling might be achieved by PDLSCs. PMID:25550827

Shen, Tao; Qiu, Lin; Chang, Huijun; Yang, Yanchun; Jian, Congxiang; Xiong, Jian; Zhou, Jixiang; Dong, Shiwu

2014-01-01

69

In vitro Osteogenic impulse effect of Dexamethasone on periodontal ligament stem cells  

Science.gov (United States)

Periodontium is a complex organ composed of mineralized epithelial and connective tissue. Dexamethasone could stimulate proliferation of osteoblast and fibroblasts. This study aimed to assess the osteogenic effect of dexamethasone on periodental ligament (PDL) stem cells. PDL stem cells were collected from periodontal ligament tissue of root of extracted premolar of young and healthy people. The stem cells were cultured in ?-MEM Medium in three groups, one group with basic medium contains (?- MEM and FBS 10 % and 50 mmol of ?_ gelisrophosphat and L_ ascorbic acid µg/ml), the second group: basic medium with dexamethasone and the third one: basic medium without any osteogenic stimulant. Mineralization of cellular layer was analyzed with Alizarin red stain method. Osteogenic analysis was done by Alkaline phosphates and calcium test. These analysis indicated that the amount of intra-cellular calcium and alkaline phosphates in the Dexamethasone group was far more than the control and basic group (Pcells in Dexamethasone group (Pstem cells and further studies are recommended to evaluate its effect on treatment of bone disorders. PMID:25848170

Roozegar, Mohamad Ali; Mohammadi, Tayebeh Malek; Havasian, Mohamad Reza; Panahi, Jafar; Hashemian, Amirreza; Amraei, Mansur; Hoshmand, Behzad

2015-01-01

70

Enhanced bone-forming activity of side population cells in the periodontal ligament.  

Science.gov (United States)

Regeneration of alveolar bone is critical for the successful treatment of periodontal diseases. The periodontal ligament (PDL) has been widely investigated as a source of cells for the regeneration of periodontal tissues. In the present study where we attempted to develop an effective strategy for alveolar bone regeneration, we examined the osteogenic potential of side population (SP) cells, a stem cell-containing population that has been shown to be highly abundant in several kinds of tissues, in PDL cells. Isolated SP cells from the rat PDL exhibited a superior ability to differentiate into osteoblastic cells compared with non-SP (NSP) and unsorted PDL cells in vitro. The mRNA expressions of osteoblast markers and bone morphogenetic protein (BMP) 2 were significantly upregulated in SP cells and were further increased by osteogenic induction. To examine the bone-forming activity of SP cells in vivo, PDL SP cells isolated from green fluorescent protein (GFP)-transgenic rats were transplanted with hydroxyapatite (HA) disks into wild-type animals. SP cells exhibited a high ability to induce the mineralized matrix compared with NSP and unsorted PDL cells. At 12 weeks after the implantation, some of the pores in the HA disks with SP cells were filled with mineralized matrices, which were positive for bone matrix proteins, such as osteopontin, bone sialoprotein, and osteocalcin. Furthermore, osteoblast- and osteocyte-like cells on and in the bone-like mineralized matrices were GFP positive, suggesting that the matrices were directly formed by the transplanted cells. These results suggest that PDL SP cells possess enhanced osteogenic potential and could be a potential source for cell-based regenerative therapy for alveolar bone. PMID:23394738

Ninomiya, Tadashi; Hiraga, Toru; Hosoya, Akihiro; Ohnuma, Kiyoshi; Ito, Yuzuru; Takahashi, Masafumi; Ito, Susumu; Asashima, Makoto; Nakamura, Hiroaki

2014-04-01

71

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

Scientific Electronic Library Online (English)

Full Text Available 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

72

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.

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Migration of Periodontal Ligament Fibroblasts on Nanometric Topographical Patterns: Influence of Filopodia and Focal Adhesions on Contact Guidance  

Science.gov (United States)

Considered to be the “holy grail” of dentistry, regeneration of the periodontal ligament in humans remains a major clinical problem. Removal of bacterial biofilms is commonly achieved using EDTA gels or lasers. One side effect of these treatment regimens is the etching of nanotopographies on the surface of the tooth. However, the response of periodontal ligament fibroblasts to such features has received very little attention. Using laser interference lithography, we fabricated precisely defined topographies with continuous or discontinuous nanogrooves to assess the adhesion, spreading and migration of PDL fibroblasts. PDL fibroblasts adhered to and spread on all tested surfaces, with initial spreading and focal adhesion formation slower on discontinuous nanogrooves. Cells had a significantly smaller planar area on both continuous and discontinuous nanogrooves in comparison with cells on non-patterned controls. At 24 h post seeding, cells on both types of nanogrooves were highly elongated parallel to the groove long axis. Time-lapse video microscopy revealed that PDL fibroblast movement was guided on both types of grooves, but migration velocity was not significantly different from cells cultured on non-patterned controls. Analysis of filopodia formation using time-lapse video microscopy and labeling of vinculin and F-actin revealed that on nanogrooves, filopodia were highly aligned at both ends of the cell, but with increasing time filopodia and membrane protrusions developed at the side of the cell perpendicular to the cell long axis. We conclude that periodontal ligament fibroblasts are sensitive to nanotopographical depths of 85–100 µm, which could be utilized in regeneration of the periodontal ligament. PMID:21152020

Hamilton, Douglas W.; Oates, Christine J.; Hasanzadeh, Abdollah; Mittler, Silvia

2010-01-01

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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

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HtrA1 may regulate the osteogenic differentiation of human periodontal ligament cells by TGF-?1.  

Science.gov (United States)

Periodontal ligament cells (PDLCs) in periodontal ligament (PDL) can differentiate into osteoblasts, while physiologically PDL remains non-mineralized space although located two hard tissues. But the exact mechanism of which is still unclear. High-temperature requirement protein A1 (HtrA1) is a key mineralization regulator and could inhibit the osteogenesis by transforming growth factor-? (TGF-?) signaling. However, the role of HtrA1 in PDLCs osteogenic differentiation has yet to be clarified. We assume HtrA1 may play an important role in maintaining the balance of PDL mineralization, and may regulate human periodontal ligament cells (hPDLCs) osteogenic differentiation by TGF-?1. Firstly we confirmed the mRNA expression of HtrA1 and TGF-?1 in hPDLCs by RT-PCR, then QDs-based immunofluorescence demonstrated the co-localization of them in the cytoplasm, and co-immunoprecipitation further confirmed the interaction between them. Lentivirus-mediated HtrA1 overexpression enhanced the osteogenic differentiation of hPDLCs, as well as up-regulation of TGF-?1. In contrast, knockdown of HtrA1 suppressed the osteogenic differentiation with down-regulation of TGF-?1. These findings suggested that HtrA1 plays a positive role in hPDLCs osteogenic differentiation and may regulate this process by TGF-?1. PMID:25726184

Li, Ran; Zhang, Qi

2015-04-01

76

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

77

Human periodontal ligament cells facilitate leukocyte recruitment and are influenced in their immunomodulatory function by Th17 cytokine release.  

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The objective of this in vitro study was to examine the immunomodulatory impact of human periodontal ligament (PDL) cells on the nature and magnitude of the leukocyte infiltrate in periodontal inflammation, particularly with regard to Th17 cells. PDL cells were challenged with pro-inflammatory cytokines (IL-1ß, IL-17A, and IFN-?) and analyzed for the expression of cytokines involved in periodontal immunoinflammatory processes (IL-6, MIP-3 alpha, IL-23A, TGFß1, IDO, and CD274). In order to further investigate a direct involvement of PDL cells in leukocyte function, co-culture experiments were conducted. The expression of the immunomodulatory cytokines studied was significantly increased under pro-inflammatory conditions in PDL cells. Although PDL cells did not stimulate leukocyte proliferation or Th17 differentiation, these cells induced the recruitment of leukocytes. The results of our study suggest that PDL cells might be involved in chronic inflammatory mechanisms in periodontal tissues and thus in the transition to an adaptive immune response in periodontitis. PMID:22119482

Konermann, A; Beyer, M; Deschner, J; Allam, J P; Novak, N; Winter, J; Jepsen, S; Jäger, A

2012-01-01

78

IL-6 trans-signaling enhances CCL20 production from IL-1?-stimulated human periodontal ligament cells.  

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CC chemokine ligand 20 (CCL20) plays a central role in the recruitment of CCR6-expressing cells, including Th17 cells which are related to bone resorption in periodontal lesions and thus in the development of periodontal disease. IL-6 is an important cytokine that is associated with the pathogenesis of periodontitis. However, the effect of IL-6 on CCL20 production is uncertain. The aim of this study was to examine whether IL-6 could modify CCL20 expression in human periodontal ligament cells (HPDLCs). HPDLCs expressed gp130 but did not express IL-6R on the surface of HPDLCs. So, IL-6 trans-signaling is important to recognize IL-6 by HPDLCs. IL-6/sIL-6R stimulation enhanced CCL20 production in IL-1?-stimulated HPDLCs. IL-6 produced from IL-1?-stimulated HPDLCs with sIL-6R could increase CCL20 production in HPDLCs with sIL-6R. Signal transducer and activator of transcription (STAT)3 activation was related to CCL20 production in IL-1? and IL-6/sIL-6R-stimulated HPDLCs. Our data suggests that HPDLCs, in response to IL-6, sIL-6R, and IL-1?, may shift chemokine production to that favoring CCR6-expressing cells recruitment in periodontal lesions. PMID:24081898

Hosokawa, Yoshitaka; Shindo, Satoru; Hosokawa, Ikuko; Ozaki, Kazumi; Matsuo, Takashi

2014-04-01

79

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

80

Comparison of dynamic shear properties of the porcine molar and incisor periodontal ligament.  

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The role of the periodontal ligament (PDL) is to support the tooth during function and resist external forces applied to it. The dominant vertical component of these forces is associated with shear in the PDL. The mechanical response to vertical force may, however, be different between the molar and incisor as their loading regimen is different. The present study was designed to determine the viscoelastic behavior in shear of the PDL of the porcine molar and incisor (n = 10 for each). From dissected mandibles transverse sections including the mesial root of first molar and the incisal root were obtained and used for dynamic shear tests. Shear strain of 1.0% was applied in superoinferior direction parallel to the root axis with a wide range of frequencies (0.01-100 Hz). The viscoelastic behavior was characterized by the storage and loss modulus and loss tangent as a function of the frequency. For the incisor and molar, the complex and storage moduli increased significantly with the frequency. For the incisor, the loss modulus also increased with the frequency. The loss modulus and loss tangent were significantly (p shear than the molar one, which might have important implications for the principal role of the anterior teeth such as PDL sensation. PMID:17063388

Tanaka, Eiji; Inubushi, Toshihiro; Koolstra, Jan Harm; van Eijden, Theo M G J; Sano, Ryota; Takahashi, Koji; Kawai, Nobuhiko; Rego, Emanuel B; Tanne, Kazuo

2006-12-01

81

Oscillatory shear loading of bovine periodontal ligament--a methodological study.  

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This study examined the stress response of bovine periodontal ligament (PDL) under sinusoidal straining. The principle of the test consisted in subjecting transverse tooth, PDL and bone sections of known geometries to controlled oscillatory force application. The samples were secured to the actuator by support plates fabricated using a laser sintering technique to fit their contours to the tooth and the alveolar bone. The actuator was attached to the root slices located in the specimen's center. Hence the machine was able to push or pull the root relative to its surrounding alveolar bone. After determining an optimal distraction amplitude, the samples were cyclically loaded first in ramps and then in sinusoidal oscillations at frequencies ranging from 0.2 to 5 Hz. In the present study the following observations were made: (1) Imaging and the laser sintering technique can be used successfully to fabricate custom-made support plates for cross-sectional root-PDL-bone sections using a laser sintering technique, (2) the load-response curves were symmetric in the apical and the coronal directions, (3) both the stress response versus phase angle and the stress response versus. strain curves tended to "straighten" with increasing frequency, and (4) the phase lag between applied strain and resulting stress was small and did not differ in the intrusive and the extrusive directions. As no mechanical or time-dependent anisotropy was demonstrable in the intrusive and extrusive directions, such results may considerably simplify the development of constitutive laws for the PDL. PMID:16706594

Sanctuary, Colin S; Wiskott, H W Anselm; Botsis, John; Scherrer, Susanne S; Belser, Urs C

2006-06-01

82

Nonlinear stress-strain behavior of periodontal ligament under orthodontic loading.  

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Previous studies of the periodontal ligament (PDL) have applied high forces to the dental units to examine the stress-strain behavior of this soft tissue. In this study, cadaveric specimens of mandibular premolars from 2 young adult and 2 elderly adult donors were tested to determine the biomechanical behavior of the PDL over an orthodontic force range. Transverse specimens were prepared from 9 premolars and subjected to loading in intrusion and extrusion. Stress-strain curves for both loading directions had distinct toe and linear regions, demonstrating nonlinear behavior of the PDL. The average linear shear modulus was higher for intrusion than for extrusion. The toe extrusive modulus was higher for the young group, and extrusive toe size was larger for the elderly group. In extrusion, the average modulus was higher for the cervical margin and the apex regions than for the midroot regions. The size of the toe region was smaller for intrusion than extrusion. The results indicate age-dependent, location-dependent, and load-direction-dependent nonlinear properties of the human PDL and suggest that analytical computer simulations of orthodontic tooth movements might benefit from incorporating the nonlinear material properties of the PDL. PMID:12165771

Toms, Stephanie R; Lemons, Jack E; Bartolucci, Alfred A; Eberhardt, Alan W

2002-08-01

83

Effects of laser therapy on the proliferation of human periodontal ligament stem cells.  

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Low-level laser irradiation (LLLI) stimulates the proliferation of a variety of cell types. However, very little is known about the effect of laser therapy on dental stem cells. The aim of the present study was to evaluate the effect of LLLI (660 nm, 30 mW) on the proliferation rate of human periodontal ligament stem cells (hPDLSC), obtained from two healthy permanent third molars extracted due to surgical indication. Culture cells were either irradiated or not (control) with an InGaAIP diode laser at 0 and 48 h, using two different energy densities (0.5 J/cm², 16 s and 1.0 J/cm², 33 s). Cell proliferation was evaluated by the Trypan blue exclusion method and by measuring mitochondrial activity using the MTT-based cytotoxicity assay at intervals of 0, 24, 48, and 72 h after the first laser application. An energy density of 1.0 J/cm² improved the cell proliferation in comparison to the other groups (control and laser 0.5 J/cm²) at 48 and 72 h. The group irradiated with 1.0 J/cm² presented significantly higher MTT activity at 48 and 72 h when compared to the energy density of 0.5 J/cm². It can be concluded that LLLI using infrared light and an energy density of 1.0 J/cm² has a positive stimulatory effect on the proliferation of hPDLSC. PMID:24013624

Soares, Diego Moura; Ginani, Fernanda; Henriques, Águida Gomes; Barboza, Carlos Augusto Galvão

2015-04-01

84

Expression and effects of epidermal growth factor on human periodontal ligament cells.  

Science.gov (United States)

Repair of damaged periodontal ligament (PDL) tissue is an essential challenge in tooth preservation. Various researchers have attempted to develop efficient therapies for healing and regenerating PDL tissue based on tissue engineering methods focused on targeting signaling molecules in PDL stem cells and other mesenchymal stem cells. In this context, we investigated the expression of epidermal growth factor (EGF) in normal and surgically wounded PDL tissues and its effect on chemotaxis and expression of osteoinductive and angiogenic factors in human PDL cells (HPDLCs). EGF as well as EGF receptor (EGFR) expression was observed in HPDLCs and entire PDL tissue. In a PDL tissue-injured model of rat, EGF and IL-1? were found to be upregulated in a perilesional pattern. Interleukin-1? induced EGF expression in HPDLCs but not EGFR. It also increased transforming growth factor-? (TGF-?) and heparin-binding EGF-like growth factor (HB-EGF) expression. Transwell assays demonstrated the chemotactic activity of EGF on HPDLCs. In addition, EGF treatment significantly induced secretion of bone morphogenetic protein 2 and vascular endothelial growth factor, and gene expression of interleukin-8 (IL-8), and early growth response-1 and -2 (EGR-1/2). Human umbilical vein endothelial cells developed well-formed tube networks when cultured with the supernatant of EGF-treated HPDLCs. These results indicated that EGF upregulated under inflammatory conditions plays roles in the repair of wounded PDL tissue, suggesting its function as a prospective agent to allow the healing and regeneration of this tissue. PMID:24850273

Teramatsu, Yoko; Maeda, Hidefumi; Sugii, Hideki; Tomokiyo, Atsushi; Hamano, Sayuri; Wada, Naohisa; Yuda, Asuka; Yamamoto, Naohide; Koori, Katsuaki; Akamine, Akifumi

2014-09-01

85

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

86

Biological behavior of neurally differentiated periodontal ligament stem cells on different titanium implant surfaces.  

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We investigated the biological behavior of periodontal ligament stem cells (PDLSCs) induced to differentiate into Schwann cells (SCs) on the surfaces of titanium discs. Two types of titanium surfaces, sand blasted and acid etched (SA) and smooth polished, were prepared on titanium discs, and the behavior of SC-like cells on these discs was investigated. Cell morphology was examined by scanning electron microscopy, and cell proliferation was assessed using assays for methylthiazol tetrazolium metabolism and total protein content. Real-time polymerase chain reaction and Western blotting analyses were used to determine the gene and protein expression, respectively, of SC markers by PDLSCs. Differentiated PDLSCs could adhere, proliferate, differentiate, and express SC marker genes and proteins on the prepared titanium surfaces, and the highest levels of SC marker protein expression were observed in PDLSCs on SA titanium surfaces. SA titanium surfaces show good biocompatibility for the SC-like cells, which is important for the application of these cells in peri-implant nerve tissue engineering, through which they are expected to improve the osseoperception of dental implants. PMID:24124075

Li, Xiaojie; Liao, Dapeng; Gong, Ping; Dong, Yan; Sun, Gang

2014-08-01

87

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)

88

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

89

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

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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

2015-02-01

90

microRNA-21 mediates stretch-induced osteogenic differentiation in human periodontal ligament stem cells.  

Science.gov (United States)

microRNAs (miRNAs) are short 20- to 22-nucleotide noncoding RNAs that negatively regulate the expression of target genes at the post-transcriptional level. The expression of specific miRNAs and their roles in the osteogenic differentiation of human periodontal ligament stem cells (PDLSCs) exposed to mechanical stretch remain unclear. Here, we found that stretch induced both osteogenic differentiation and the differential expression of miR-21 in PDLSCs. Furthermore, we identified activin receptor type IIB (ACVR2B) as a target gene of miR-21. Luciferase reporter assays showed that miR-21 interacts directly with the 3'-untranslated repeat sequence of ACVR2B mRNA. Mechanical stretch suppressed ACVR2B protein levels in PDLSCs, and this suppressive effect was modulated when endogenous miR-21 levels were either enhanced or inhibited. Both stretch and the expression of miR-21 altered endogenous ACVR2B protein levels and thus the osteogenic differentiation of PDLSCs. In addition, gain- and loss of function of ACVR2B mediated the osteogenic differentiation of PDLSCs. This study demonstrates that miR-21 is a mechanosensitive gene that plays an important role in the osteogenic differentiation of PDLSCs exposed to stretch. PMID:25203845

Wei, Fulan; Liu, Dongxu; Feng, Cheng; Zhang, Fan; Yang, Shuangyan; Hu, Yijun; Ding, Gang; Wang, Songlin

2015-02-01

91

Transdifferentiation of human periodontal ligament stem cells into pancreatic cell lineage.  

Science.gov (United States)

Human periodontal ligament-derived stem cells (PDLSCs) demonstrate self-renewal capacity and multilineage differentiation potential. In this study, we investigated the transdifferentiation potential of human PDLSCs into pancreatic islet cells. To form three-dimensional (3D) clusters, PDLSCs were cultured in Matrigel with media containing differentiation-inducing agents. We found that after 6?days in culture, PDLSCs underwent morphological changes resembling pancreatic islet-like cell clusters (ICCs). The morphological characteristics of PDLSC-derived ICCs were further assessed using scanning electron microscopy analysis. Using reverse transcription-polymerase chain reaction analysis, we found that pluripotency genes were downregulated, whereas early endoderm and pancreatic differentiation genes were upregulated, in PDLSC-derived ICCs compared with undifferentiated PDLSCs. Furthermore, we found that PDLSC-derived ICCs were capable of secreting insulin in response to high concentrations of glucose, validating their functional differentiation into islet cells. Finally, we also performed dithizone staining, as well as immunofluorescence assays and fluorescence-activated cell sorting analysis for pancreatic differentiation markers, to confirm the differentiation status of PDLSC-derived ICCs. These results demonstrate that PDLSCs can transdifferentiate into functional pancreatic islet-like cells and provide a novel, alternative cell population for pancreatic repair. PMID:25187163

Lee, Jeong Seok; An, Seong Yeong; Kwon, Il Keun; Heo, Jung Sun

2014-10-01

92

Gene-enhanced tissue engineering for dental hard tissue regeneration: (2) dentin-pulp and periodontal regeneration  

OpenAIRE

Abstract Potential applications for gene-based tissue engineering therapies in the oral and maxillofacial complex include the delivery of growth factors for periodontal regeneration, pulp capping/dentin regeneration, and bone grafting of large osseous defects in dental and craniofacial reconstruction. Part 1 reviewed the principals of gene-enhanced tissue engineering and the techniques of introducing DNA into cells. This manuscript will review recent advances in gene-based therapies for denta...

Mason James M.; Edwards Paul C

2006-01-01

93

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

94

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 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

95

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

96

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  

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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

97

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

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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

98

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

99

Comparison of Coconut Water and Jordanian Propolis on Survival of Bench-dried Periodontal Ligament Cells: An in vitro Cell Culture Study  

OpenAIRE

Aim: The aim of this study is to assess and compare the efficacy of Jordanian propolis and full concentration mature coconut water in their ability to preserve periodontal ligament (PDL) cell viability after exposure of PDL cells to up to 120 minutes dry storage.

Al-haj Ali, Sanaa Najeh; Al-jundi, Suhad; Mhaidat, Nizar

2013-01-01

100

Participación de MT1-MMP en la Remodelación del Ligamento Periodontal Durante la Movilización Dentaria / Role of MT1-MMP in the Remodeling of the Periodontal Ligament During Tooth Movement  

Scientific Electronic Library Online (English)

Full Text Available La movilización dentaria involucra una serie de cambios en los tejidos de soporte caracterizados por la activa remodelación de estos. La MT1-MMP o MMP-14 es una potente enzima proteolítica capaz de degradar colágeno tipo I, la principal molécula estructural del ligamento periodontal. La migración de [...] ntaria requiere de la degradación controlada del colágeno constituyente del ligamento periodontal. Sin embargo, no existen evidencias de la participación de MT1-MMP en la remodelación del tejido periodontal durante este proceso. En el presente estudio hemos analizado la expresión de MT1 -MMP y del marcador de actividad osteoclástica Fosfatasa Acida Tartrato Resistente (TRAP) en un modelo de migración dentaria en ratas. La migración dentaria fue activada mediante la inserción de una banda separadora entre los incisivos superiores. La expresión y distribución de TRAP y MT1-MMP fue evaluada a través de citoquímica e inmunohistoquímica a los días 1, 3, 5 y 7. La producción de TRAP fue identificada principalmente en osteoclastos ubicados en la zona de compresión del ligamento periodontal. La producción de MT1-MMP fue observada en fibroblastos de la zona de compresión del ligamento periodontal y osteoclastos ubicados en esta misma región. Nuestros resultados permiten proponer que tanto MT1 -MMP como TRAP participan en la remodelación de los tejidos de soporte periodontal durante la migración dentaria. Abstract in english Tooth movement involves a series of changes of the supporting periodontal tissues characterized by the active connective tissue remodeling. MT1-MMP or MMP-14 belongs to the family of matrix metalloproteinases that are able to degrade type I collagen, the main molecule involved in periodontal attachm [...] ent. Tooth migration requires the controlled degradation of periodontal ligament collagen fibers. However, evidences linking MT1 -MMP expression with periodontal tissue remodeling are lacking. In the present study, we have evaluated the expression of MT1-MMPand of the osteoclast marker Tartrate Resistant Acid Phosphatase (TRAP) in a model of tooth migration in rats. Tooth migration was induced after the insertion of a rubber band between the upper incisors. The distribution of TRAP and MT1 -MMP was evaluated by means of cytochemistry and immunohistochemistry respectively at days 1, 3, 5 and 7. TRAP production was identified in osteoclasts at the area of compression of the periodontal ligament. MT1-MMP distribution was observed in fibroblastsatthe compressed area of the periodontal ligament and also in osteoclasts of the same region. Our findings allow us to propose that MT1-MMP and TRAP take part of the tissue remodeling events observed during tooth movement.

P, Rey Droghetti; F, Cruzat; P, Smith Ferrer; A, Oyarzún Droguett.

2010-12-01

101

Comparação entre fibroblastos gengivais e do ligamento periodontal de um mesmo indivíduo / Comparison between gingival and periodontal ligament fibroblasts from the same subject  

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Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo deste estudo foi comparar as características morfológicas, o potencial proliferativo e a produção protéica de fibroblastos do ligamento periodontal (FLP) e de fibroblastos gengivais (FG). Os fibroblastos foram cultivados pela técnica do explante a partir de fragmentos da gengiva e do liga [...] mento periodontal de um mesmo indivíduo. As células foram isoladas e plaqueadas para análise por microscopia de contraste de fase e microscopia óptica. O índice de proliferação celular foi determinado por contagem automática de células e pelo ensaio de incorporação de bromodioxiuridina (BrdU). A produção de proteína total foi verificada por eletroforese em gel de poliacrilamida e o perfil enzimático por análise zimográfica. Os FLP são maiores e mais alongados que os FG em condições de subconfluência e confluência celular. Os FLP demonstraram um potencial proliferativo significantemente maior que os FG. Os perfis protéico e enzimático foram similares entre os FLP e FG. Os resultados demonstram que os FLP e FG são diferentes na morfologia e na capacidade proliferativa, porém são semelhantes na produção protéica. Abstract in english The objective of this study was to compare fibroblasts from the periodontal ligament (PLF) and gingival fibroblasts (GF) as to morphology, proliferation rate and protein synthesis. PLF and GF were explanted from tissues of the same patient. To characterize and compare the morphology of cells, PLF an [...] d GF were plated and analyzed under phase-contrast and optical microscopies. Proliferation rates were determined by means of automated counts carried out in days 1, 4, 7, 15 and 21, and also by means of the bromodeoxyuridine labelling index (BrdU). Total protein content was analyzed by means of electrophoresis in 10% polyacrylamide gel and zimography containing gelatin as substrate. PLF were bigger and more elongated than GF in subconfluence and confluence conditions. The proliferative rate of PLF was higher than that of GF at 1, 4, and 7 days (p

Daniela Bazan, Palioto; Ricardo, Della Coletta; Hercílio, Martelli Júnior; Julio Cesar, Joly; Edgard, Graner; Antonio Fernando Martorelli de, Lima.

2002-12-01

102

Matrix metalloproteinases regulate extracellular levels of SDF-1/CXCL12, IL-6 and VEGF in hydrogen peroxide-stimulated human periodontal ligament fibroblasts.  

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Periodontitis is a highly prevalent infectious disease characterized by the progressive inflammatory destruction of tooth-supporting structures, leading to tooth loss. The underling molecular mechanisms of the disease are incompletely understood, precluding the development of more efficient screening, diagnostic and therapeutic approaches. We investigated the interrelation of three known effector mechanisms of the cellular response to periodontal infection, namely reactive oxygen species (ROS), matrix metalloproteinases (MMPs) and cytokines in primary cell cultures of human periodontal ligament fibroblast (hPDLF). We demonstrated that ROS increase the activity/levels of gelatinolytic MMPs, and stimulate cytokine secretion in hPDLF. Additionally, we proved that MMPs possesses immune modulatory capacity, regulating the secreted levels of cytokines in ROS-stimulated hPDLF cultures. This evidence provides further insight in the molecular pathogenesis of periodontitis, contributing to the future development of more effective therapies. PMID:25748833

Cavalla, Franco; Osorio, Constanza; Paredes, Rodolfo; Valenzuela, María Antonieta; García-Sesnich, Jocelyn; Sorsa, Timo; Tervahartiala, Taina; Hernández, Marcela

2015-05-01

103

In vitro mechanical loading models for periodontal ligament cells: from two-dimensional to three-dimensional models.  

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Periodontal ligament cells (PDLCs) respond to various mechanical stimuli, including mastication and orthodontic force, and thereby play an important functional role. A number of in vitro models have been widely used to study these mechanoresponses. Here, we comprehensively review the various in vitro mechanical loading approaches used for assessing PDLCs, including their force generation properties, mechanical characteristics, and simulation of authentic bioprocesses. Furthermore, we highlight the evolution of current cytomechanical studies, from conventional two-dimensional to novel three-dimensional (3-D) cell cultures. Some representative 3-D PDLC culture and mechanical loading systems are also described, with the advantages and limitations of these discussed. From this review, we can conclude that optimal mechanical loading models must be chosen to match the specific research purpose, and that novel 3-D PDLC culture and mechanical loading models are promising for future studies. PMID:25526626

Yang, Liang; Yang, Yan; Wang, Shuai; Li, Yu; Zhao, Zhihe

2015-03-01

104

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

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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

105

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

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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

106

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

107

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

108

Anti-inflammatory effects of lindenenyl acetate via heme oxygenase-1 and AMPK in human periodontal ligament cells.  

Science.gov (United States)

The molecular basis for the anti-inflammatory effects of lindenenyl acetate (LA) was investigated in the lipopolysaccharide (LPS)-stimulated human periodontal ligament (HPDL) cell model. LA concentration-dependently inhibited LPS-induced inducible nitric oxide synthase (iNOS) derived nitric oxide (NO) and cyclooxygenase-2 (COX-2) derived prostaglandin E2 (PGE(2)) production in HPDL cells. LA also attenuated the production of LPS-induced tumor necrosis factor (TNF)-?, interleukin (IL)-1?, IL-6 and IL-12. LA stimulated heme oxygenase-1 (HO-1) protein expression and enzyme activity of HPDL cells in a dose-dependent manner. Pretreatment with the HO-1 inhibitor, tin protoporphyrin (SnPP), attenuated the inhibitory activities of LA on LPS-induced inflammatory NO, PGE(2), IL-1?, TNF-?, IL-6 and IL-12 production. LA induced translocation of Nrf-2. Furthermore, an inhibitor of JNK MAPK abolished LA-induced HO-1 expression. LA exposure up-regulated the levels of phosphorylated adenosine monophosphate-activated protein kinase (AMPK) and its upstream kinase activators, including LKB1 and Ca2+/calmodulin-dependent protein kinase kinase-II. Furthermore, compound C, a specific AMPK inhibitor, partially blocked the LA-induced anti-inflammatory effect. Taken together, these results indicate that LA has anti-inflammatory activity in HPDL cells that might be mediated by the HO-1, AMPK, JNK MAPK, and Nrf-2 pathways. Thus, LA may serve as a potential therapeutic agent in periodontal disease. PMID:21910986

Jeong, Gil-Saeng; Lee, Dong-Sung; Li, Bin; Kim, Jong-Jin; Kim, Eun-Cheol; Kim, Youn-Chul

2011-11-16

109

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  

OpenAIRE

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 s...

Ge S; Zhao N; Wang L.; Liu H.; Yang P

2013-01-01

110

The effect of velocity of loading on the biomechanical responses of the periodontal ligament in transverse sections of the rat molar in vitro.  

Science.gov (United States)

Stress-strain relations of this ligament in transverse sections of the mandibular first molar were examined over a wide range of velocities of loading from 1 to 10(4) mm/24 h. With increasing velocities, the maximum shear stress, tangent modulus and failure strain-energy density increased but the maximum shear strain decreased. The mechanical responses at the highest velocity for the molar ligament were compared with those previously found for the incisor ligament. Mechanical strength, stiffness and toughness were greater for the molar than for the incisor ligament; the molar ligament therefore has more extensible fibres or a different fibre arrangement. Comparison of the mechanical responses at the slowest velocity suggests that, though the stress level was greatly reduced (presumably because of stress relaxation), the fibre components of the molar ligament still reacted at this velocity. It is also suggested that the differences in the ratios of the mechanical measures in 10(4)-1 mm/24 h between the two types of teeth are due partly to their different periodontal fibre architectures. PMID:8328919

Komatsu, K; Chiba, M

1993-05-01

111

Sodium hydrogen sulfide inhibits nicotine and lipopolysaccharide-induced osteoclastic differentiation and reversed osteoblastic differentiation in human periodontal ligament cells.  

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Although previous studies have demonstrated that hydrogen sulfide (H(2)S) stimulated or inhibited osteoclastic differentiation, little is known about the effects of H(2)S on the differentiation of osteoblasts and osteoclasts. To determine the possible bioactivities of H(2)S on bone metabolism, we investigated the in vitro effects of H(2)S on cytotoxicity, osteoblastic, and osteoclastic differentiation as well as the underlying mechanism in lipopolysaccharide (LPS) and nicotine-stimulated human periodontal ligament cells (hPDLCs). The H(2)S donor, NaHS, protected hPDLCs from nicotine and LPS-induced cytotoxicity and recovered nicotine- and LPS-downregulated osteoblastic differentiation, such as alkaline phosphatase (ALP) activity, mRNA expression of osteoblasts, including ALP, osteopontin (OPN), and osteocalcin (OCN), and mineralized nodule formation. Concomitantly, NaHS inhibited the differentiation of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts in mouse bone marrow cells and blocked nicotine- and LPS-induced osteoclastogenesis regulatory molecules, such as RANKL, OPG, M-CSF, MMP-9, TRAP, and cathepsin K mRNA. NaHS blocked nicotine and LPS-induced activation of p38, ERK, MKP-1, PI3K, PKC, and PKC isoenzymes, and NF-?B. The effects of H(2)S on nicotine- and LPS-induced osteoblastic and osteoclastic differentiation were remarkably reversed by MKP-1 enzyme inhibitor (vanadate) and expression inhibitor (triptolide). Taken together, we report for the first time that H(2)S inhibited cytotoxicity and osteoclastic differentiation and recovered osteoblastic differentiation in a nicotine- and periodontopathogen-stimulated hPDLCs model, which has potential therapeutic value for treatment of periodontal and inflammatory bone diseases. PMID:23192567

Lee, Sun-Kyung; Chung, Jong-Hyuk; Choi, Sung-Chul; Auh, Q-Schick; Lee, Young-Man; Lee, Sang-Im; Kim, Eun-Cheol

2013-05-01

112

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 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

113

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

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

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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

115

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

116

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

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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 ligame...

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

117

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 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

118

Essentials in Periodontal Regeneration  

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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

119

Periodontal ligament influence on the stress distribution in a removable partial denture supported by implant: a finite element analysis  

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Full Text Available OBJECTIVES: The non-homogenous aspect of periodontal ligament (PDL has been examined using finite element analysis (FEA to better simulate PDL behavior. The aim of this study was to assess, by 2-D FEA, the influence of non-homogenous PDL on the stress distribution when the free-end saddle removable partial denture (RPD is partially supported by an osseointegrated implant. MATERIAL AND METHODS: Six finite element (FE models of a partially edentulous mandible were created to represent two types of PDL (non-homogenous and homogenous and two types of RPD (conventional RPD, supported by tooth and fibromucosa; and modified RPD, supported by tooth and implant [10.00x3.75 mm]. Two additional Fe models without RPD were used as control models. The non-homogenous PDL was modeled using beam elements to simulate the crest, horizontal, oblique and apical fibers. The load (50 N was applied in each cusp simultaneously. Regarding boundary conditions the border of alveolar ridge was fixed along the x axis. The FE software (Ansys 10.0 was used to compute the stress fields, and the von Mises stress criterion (svM was applied to analyze the results. RESULTS: The peak of svM in non-homogenous PDL was higher than that for the homogenous condition. The benefits of implants were enhanced for the non-homogenous PDL condition, with drastic svM reduction on the posterior half of the alveolar ridge. The implant did not reduce the stress on the support tooth for both PDL conditions. Conclusion: The PDL modeled in the non-homogeneous form increased the benefits of the osseointegrated implant in comparison with the homogeneous condition. Using the non-homogenous PDL, the presence of osseointegrated implant did not reduce the stress on the supporting tooth.

Carlos Marcelo Archangelo

2012-06-01

120

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

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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

121

Brain-Derived Neurotrophic Factor in Chronic Periodontitis  

Science.gov (United States)

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 periodontitis (CP) and periodontally healthy controls (HC). All subjects were genotyped for the rs4923463 and rs6265 BDNF polymorphisms. Periodontal tissues were collected for ELISA, myeloperoxidase (MPO), and microscopic analysis from 28 CP patients and 29 HC subjects. BDNF levels were increased in CP patients compared to HC subjects. A negative correlation was observed when analyzing concentration of BDNF and IL-10 in inflamed periodontium. No differences in frequencies of BDNF genotypes between CP and HC subjects were observed. However, BDNF genotype GG was associated with increased levels of BDNF, TNF-?, and CXCL10 in CP patients. In conclusion, BDNF seems to be associated with periodontal disease process, but the specific role of BDNF still needs to be clarified. PMID:25587209

Corrêa, Jôice Dias; Pereira, Daniele Sirineu; Madeira, Mila Fernandes Moreira; Queiroz-Junior, Celso Martins; Souza, Danielle Glória; Teixeira, Mauro Martins; Costa, José Eustáquio; Teixeira, Antônio Lúcio; da Silva, Tarcília Aparecida

2014-01-01

122

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

123

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

Science.gov (United States)

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

124

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.

125

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

126

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

127

20-Hydroxyecdysone-induced bone morphogenetic protein-2-dependent osteogenic differentiation through the ERK pathway in human periodontal ligament stem cells.  

Science.gov (United States)

20-Hydroxyecdysone, an ecdysteroid hormone, can induce osteogenic differentiation in mesenchymal stem cells. Periodontal ligament stem cells (PDLS cells) have mesenchymal-stem-cell-like qualities and are considered as one of the candidates of future clinical application in periodontitis treatment. However, there are no studies describing the effect of 20-Hydroxyecdysone on PDLS cells. In this paper, we report a detailed study on the effect of 20-Hydroxyecdysone on PDLS cell proliferation in vitro. PDLS cells were developed from human PDL cells and were treated with 20-Hydroxyecdysone to understand different aspects of its effects. 20-Hydroxyecdysone promoted PDLS cell proliferation; significantly increased the gene expression levels of runt-related transcription factor 2, alkaline phosphatase (ALP), type I collagen, and osteocalcin. Moreover, 20-Hydroxyecdysone enhanced bone formation by PDLS cells and significantly increased bone morphogenetic protein-2 (BMP-2) mRNA and protein expression. However, 20-Hydroxyecdysonemediated increase in ALP activity was blocked with a BMP-2-specific neutralizing antibody or with the antagonist noggin; and20-Hydroxyecdysone mediated induction of BMP-2 expression and increase of ALP activity were abolished by the extracellular regulated protein kinase (ERK) MAPK pathway inhibitor PD98059. 20-Hydroxyecdysone also increased the phosphorylation of ERK. These findings provide evidence to state that 20-Hydroxyecdysone stimulates cell proliferation and induces osteogenic differentiation through the induction of BMP-2 expression in PDLS cells. It also shows that the ERK pathway is involved in 20-Hydroxyecdysone induced BMP-2 expression and osteogenic differentiation. These results are suggesting its potential as a drug for periodontal regenerative therapy. PMID:23397605

Jian, Cong-Xiang; Liu, Xiao-Fei; Hu, Jun; Li, Chen-Jun; Zhang, Gang; Li, Yan; Zhu, Ji-Wen; Tan, Ying-Hui

2013-01-01

128

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

OpenAIRE

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 moviment...

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

2009-01-01

129

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

130

IL-17R activation of human periodontal ligament fibroblasts induces IL-23 p19 production: Differential involvement of NF-?B versus JNK/AP-1 pathways.  

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Interleukin (IL)-23 is an essential cytokine involved in the expansion of a novel CD4(+) T helper subset known as Th17, which has been implicated in the pathogenesis of periodontitis recently. This study hypothesised that Th17 signature cytokine IL-17 may target specialised human periodontal ligament fibroblasts (hPDLFs) for production of IL-23 p19, a key subunit of IL-23. Primary hPDLFs had steady expression of IL-17 receptor (IL-17R) mRNA and surface-bound protein. IL-17 was capable of stimulating the expression of IL-23 p19 mRNA and protein in cultured hPDLFs, which was attenuated by IL-17 or IL-17R neutralising antibodies. In accordance with the enhanced expression of IL-23 p19, IL-17 stimulation resulted in rapid activation of Akt, p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK) 1/2, c-Jun-N-terminal kinase (JNK), nuclear factor-kappaB (NF-?B), and activator protein-1 (AP-1) in hPDLFs. Inhibitors of Akt, p38 MAPK, ERK 1/2, or NF-?B significantly suppressed, whereas blocking JNK and AP-1 substantially augmented IL-23 p19 production from IL-17-stimulated hPDLFs. Moreover, IL-17-initiated NF-?B activation was blocked by Akt, p38 MAPK, or ERK 1/2 inhibition, while AP-1 activity was specifically abrogated by JNK inhibition. Thus, these results provide evidence that hPDLFs are a target of Th17, and that IL-17 appears to up-regulate the expression of IL-23 p19 via a homeostatic mechanism involving Akt-, p38 MAPK-, and ERK 1/2-dependent NF-?B signalling versus the JNK/AP-1 pathway. Taken together, our findings suggest that disruption of the interaction between IL-17 and IL-23 may be a potential therapeutic approach in the treatment of periodontitis. PMID:21145111

Zhu, Lingxin; Wu, Yan; Wei, Hongxia; Xing, Xin; Zhan, Ni; Xiong, Haofei; Peng, Bin

2011-01-01

131

Effects of p38 Mitogen-activated Protein Kinase on Osteogenic Differentiation of Human Periodontal Ligament Stem Cells in Inflammatory Microenvironment.  

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Objective To investigate the expression of mitogen-activated protein kinase(MAPK)in the chronic periodontitis tissue-derived in the periodontal ligament stem cells(PDLSCs)and explore its effect on the osteogenic differentiation of human PDLSCs in inflammatory microenvironment. Methods PDLSCs were obtained from human healthy individuals(H-PDLSCs)and patients with periodontitis(P-PDLSCs). The tumor necrosis factor(TNF)-? and interleukin(IL)-1? secretion and mRNA expression levels of H-PDLSCs and P-PDLSCs were detected using enzyme-linked immunosorbent assay and real-time quantitative PCR. Immunofluorescence staining was used for determining the protein levels of p38 in PDLSCs. The levels of p38 and p-p38 following culture in osteogenic medium for 7 d of H-PDLSCs and P-PDLSCs were detected using Western blotting.After the PDLSCs were stimulated with SB-203580,the p38 MAPK specific inhibitor,for 30 min and then in osteogenic induction process for 7 days,the expression levels of the osteogenic gene Runx2 and alkaline phosphatase(ALP)were determined by real-time quantitative PCR,and bone formation ability of PDLSCs was tested by alizarin red(AR)staining. Results The secretions of TNF-? and IL-1? were significantly higher in P-PDLSCs compared with H-PDLSCs(68.80±6.70 vs. 34.10±3.07,P=0.001;57.10±4.23 vs. 26.90±2.58,P=0.000). The same trend was seen in the gene expression levels of both TNF-? and IL-1? in PDLSCs(PTNF-?=0.011,P IL-1?=0.009). p38 was more strongly induced in P-PDLSCs cells than in H-PDLSCs.The basal level of p38 in H-PDLSCs was lower than that in P-PDLSCs cells cultured in the basic medium. However,the level of p-p38 was increased in H-PDLSCs than in P-PDLSCs under osteogenic condition. Treatment of PDLSCs with SB-203580 and then cultures under osteogenic differentiation lead to significantly decreased expressions of Runx2 and ALP in both H-PDLSCs and P-PDLSCs(H-PDLSCs:PRunx2=0.044,PALP=0.036;P-PDLSCs:PRunx2=0.017,PALP=0.004). Conclusions p38 MAPK is involved in the inflammatory response of PDLSCs in the chronic inflammatory microenvironment. The inhibition of p38 by SB-203580 also remarkably suppresses the osteogenic differentiation of PDLSCs in a chronic inflammatory microenvironment. PMID:25676262

Nie, Jia; Zhang, Bo; Gu, Bin; Liu, Na

2015-02-12

132

Mechanical responses of the periodontal ligament in the transverse section of the rat mandibular incisor at various velocities of loading in vitro.  

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Stress-strain curves of the periodontal ligament (PDL) were obtained at various velocities of extrusive loading of 1, 10, 10(2), 10(3) and 10(4) mm/24 h in vitro. Significant increases of the maximum shear stress, tangent modulus and failure strain energy density were found with increases in the velocity of loading. The maximum shear strain increased from a velocity of 1 to 10 mm/24 h but decreased from 10 to 10(4) mm/24 h. It was shown histologically that the free surface of the PDL adhering to the cementum after mechanical testing was rough and irregular at higher velocities and rather smooth at lower velocities. These results showed that the mechanical properties and mode of failure of the rat incisor PDL were greatly dependent on the strain rate. It is possible that the PDL of the continuously erupting rat incisor has mechanical characteristics favourable for resisting weakly to slow and small eruptive forces but strongly to the fast and large occlusal forces as suggested previously [Chiba and Komatsu, The Biological Mechanisms of Tooth Eruption and Root Resorption (1988)]. PMID:8478357

Chiba, M; Komatsu, K

1993-01-01

133

Ex vivo bone morphogenetic protein 2 gene delivery using periodontal ligament stem cells for enhanced re-osseointegration in the regenerative treatment of peri-implantitis.  

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Peri-implantitis is a chronic inflammatory process with advanced bone loss and impaired healing potential. For peri-implantitis treatment, tissue engineering can be applied to enhance bone regeneration of peri-implant defects. This study aimed to evaluate ex vivo bone morphogenetic protein 2 (BMP2) gene delivery using canine periodontal ligament stem cells (PDLSCs) for regeneration of peri-implantitis defects. Canine PDLSCs were transduced with adenoviral vectors containing BMP2 (BMP2/PDLSCs). After peri-implantitis was induced by ligature placement in six beagle dogs, regenerative procedures were performed; hydroxyapatite (HA) particles and collagen gel with autologous canine PDLSCs (PDLSC group) or BMP2/PDLSCs (BMP/PDLSC group) or without cells (control group) were grafted into the defects and covered by an absorbable membrane. Three months later, the animals were sacrificed. In vitro, BMP2/PDLSCs showed similar levels of stem cell properties to PDLSCs, such as colony-forming efficiency and expression of MSC markers STRO-1 and CD 146. BMP2/PDLSCs produced BMP-2 until day 21 at a concentration of 4-8 ng/mL. In vivo, the BMP2/PDLSC group showed significantly more new bone formation and re-osseointegration in peri-implantitis defects compared to the other groups. In conclusion, ex vivo BMP2 gene delivery using PDLSCs enhanced new bone formation and re-osseointegration in peri-implantitis defects. PMID:24616330

Park, Shin-Young; Kim, Kyoung-Hwa; Gwak, Eun-Hye; Rhee, Sang-Hoon; Lee, Jeong-Cheol; Shin, Seung-Yun; Koo, Ki-Tae; Lee, Yong-Moo; Seol, Yang-Jo

2015-01-01

134

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

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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

135

Engineering the periodontal ligament in hyaluronan-gelatin-type I collagen constructs: upregulation of apoptosis and alterations in gene expression by cyclic compressive strain.  

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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

2015-02-01

136

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

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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

137

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

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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

138

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

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Blood flow changes in the periodontal ligament (PDL) were measured indirectly by monitoring the local clearance of /sup 125/I/sup -/ 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 ..cap alpha..-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 ..cap alpha.. 1 and ..cap alpha.. 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 ..cap alpha..-adrenoceptor blockade. Administration of guanethidine (which inhibits further release of NA and neuropeptide Y) after PA abolished this residual sympathetic response. 32 refs.

Edwall, B.; Gazelius, B.

1988-01-01

139

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

140

A comparative study of the proliferation and osteogenic differentiation of human periodontal ligament cells cultured on ?-TCP ceramics and demineralized bone matrix with or without osteogenic inducers in vitro.  

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The repair of bone defects that result from periodontal diseases remains a clinical challenge for periodontal therapy. ?-tricalcium phosphate (?-TCP) ceramics are biodegradable inorganic bone substitutes with inorganic components that are similar to those of bone. Demineralized bone matrix (DBM) is an acid-extracted organic matrix derived from bone sources that consists of the collagen and matrix proteins of bone. A few studies have documented the effects of DBM on the proliferation and osteogenic differentiation of human periodontal ligament cells (hPDLCs). The aim of the present study was to investigate the effects of inorganic and organic elements of bone on the proliferation and osteogenic differentiation of hPDLCs using three-dimensional porous ?-TCP ceramics and DBM with or without osteogenic inducers. Primary hPDLCs were isolated from human periodontal ligaments. The proliferation of the hPDLCs on the scaffolds in the growth culture medium was examined using a Cell?Counting kit?8 (CCK-8) and scanning electron microscopy (SEM). Alkaline phosphatase (ALP) activity and the osteogenic differentiation of the hPDLCs cultured on the ?-TCP ceramics and DBM were examined in both the growth culture medium and osteogenic culture medium. Specific osteogenic differentiation markers were examined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). SEM images revealed that the cells on the ?-TCP were spindle-shaped and much more spread out compared with the cells on the DBM surfaces. There were no significant differences observed in cell proliferation between the ?-TCP ceramics and the DBM scaffolds. Compared with the cells that were cultured on ?-TCP ceramics, the ALP activity, as well as the Runx2 and osteocalcin (OCN) mRNA levels in the hPDLCs cultured on DBM were significantly enhanced both in the growth culture medium and the osteogenic culture medium. The organic elements of bone may exhibit greater osteogenic differentiation effects on hPDLCs than the inorganic elements. PMID:25738431

An, Shaofeng; Gao, Yan; Huang, Xiangya; Ling, Junqi; Liu, Zhaohui; Xiao, Yin

2015-05-01

141

Biomechanical adaptation of the bone-periodontal ligament (PDL)-tooth fibrous joint as a consequence of disease.  

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In this study, an in vivo ligature-induced periodontitis rat model was used to investigate temporal changes to the solid and fluid phases of the joint by correlating shifts in joint biomechanics to adaptive changes in soft and hard tissue morphology and functional space. After 6 and 12 weeks of ligation, coronal regions showed a significant decrease in alveolar crest height, increased expression of TNF-?, and degradation of attachment fibers as indicated by decreased collagen birefringence. Cyclical compression to peak loads of 5-15N at speeds of 0.2-2.0mm/min followed by load relaxation tests showed decreased stiffness and reactionary load rate values, load relaxation, and load recoverability, of ligated joints. Shifts in joint stiffness and reactionary load rate increased with time while shifts in joint relaxation and recoverability decreased between control and ligated groups, complementing measurements of increased tooth displacement as evaluated through digital image correlation. Shifts in functional space between control and ligated joints were significantly increased at the interradicular (?10-25?m) and distal coronal (?20-45?m) regions. Histology revealed time-dependent increases in nuclei elongation within PDL cells and collagen fiber alignment, uncrimping, and directionality, in 12-week ligated joints compared to random orientation in 6-week ligated joints and to controls. We propose that altered strains from tooth hypermobility could cause varying degrees of solid-to-fluid compaction, alter dampening characteristics of the joint, and potentiate increased adaptation at the risk of joint failure. PMID:24332618

Lin, Jeremy D; Lee, Jihyun; Ozcoban, Hüseyin; Schneider, Gerold A; Ho, Sunita P

2014-06-27

142

Periodontitis and diabetes: a two-way relationship  

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Periodontitis is a common chronic inflammatory disease characterised by destruction of the supporting structures of the teeth (the periodontal ligament and alveolar bone). It is highly prevalent (severe periodontitis affects 10–15% of adults) and has multiple negative impacts on quality of life. Epidemiological data confirm that diabetes is a major risk factor for periodontitis; susceptibility to periodontitis is increased by approximately threefold in people with diabetes. There is a clear...

Preshaw, P. M.; Alba, A. L.; Herrera, D.; Jepsen, S.; Konstantinidis, A.; Makrilakis, K.; Taylor, R.

2011-01-01

143

Both 25-Hydroxyvitamin-D3 and 1,25-Dihydroxyvitamin-D3 Reduces Inflammatory Response in Human Periodontal Ligament Cells  

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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 for...

Andrukhov, Oleh; Andrukhova, Olena; Hulan, Ulamnemekh; Tang, Yan; Bantleon, Hans-peter; Rausch-fan, Xiaohui

2014-01-01

144

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

145

Up-regulation of IL-23 p19 expression in human periodontal ligament fibroblasts by IL-1? via concurrent activation of the NF-?B and MAPKs/AP-1 pathways.  

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Interleukin (IL)-23 is an essential cytokine involved in the expansion of a novel CD4(+) T helper subset known as Th17, which has been implicated in the pathogenesis of periodontitis recently. Our previous study first identified specialized human periodontal ligament fibroblasts (hPDLFs) as an important production source of IL-23. The present study was undertaken to investigate the effects of the pro-inflammatory and Th17-polarizing mediator IL-1? on hPDLFs-mediated IL-23 p19 production, and the molecular mechanism involved. IL-23 p19 expression was in situ detected in IL-1?-stimulated hPDLFs. IL-1? was capable of stimulating the expression of IL-23 p19 mRNA and protein in cultured hPDLFs, which was attenuated by IL-1 receptor antagonist (IL-1Ra) or myeloid differentiation primary response gene 88 (MyD88) inhibitor. Meanwhile, inhibitors of p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK) 1/2, c-Jun-N-terminal kinase (JNK), activator protein-1 (AP-1), or nuclear factor-kappaB (NF-?B) significantly suppressed IL-23 p19 production from IL-1?-stimulated hPDLFs. Moreover, IL-1?-initiated AP-1 activation was blocked by p38 MAPK, ERK 1/2, or JNK inhibition, whereas NF-?B activity remained unaltered by all the above pathway specific inhibitors. Thus, these results provide evidence that Th17-polarizing mediator IL-1? up-regulated the expression of IL-23 p19 in hPDLFs via NF-?B signaling and MAPKs-dependent AP-1 pathways. Taken together, our findings indicate that IL-1Ra may be used therapeutically to inhibit Th17-driven inflammatory diseases including periodontitis. PMID:22688014

Zhu, Lingxin; Wu, Yan; Wei, Hongxia; Yang, Shasha; Zhan, Ni; Xing, Xin; Peng, Bin

2012-10-01

146

Multifactorial Relationship of Obesity and Periodontal Disease  

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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 wor...

Suresh, Snophia; Mahendra, Jaideep

2014-01-01

147

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

148

A comparison of the effect of epidermal growth factor, platelet-derived growth factor, and fibroblast growth factor on rat periodontal ligament fibroblast-like cells' DNA synthesis and morphology  

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An enhanced formation of bone, dentin, and collagen fibers in periodontal wounds after application of polypeptide growth factors has recently been reported. However, the complex environment in vivo makes it impossible to determine the specific effects of growth factors on various cells involved in the wound-healing process. We have therefore investigated the mitogenic and morphogenic effects of recombinant epidermal growth factor (rEGF), natural platelet-derived growth factor (nPDGF), and natural fibroblast growth factor (nFGF) on periodontal ligament fibroblast-like cells. A cell line was established from rat PDL tissue. The cell line was characterized according to morphology, growth pattern, cytoskeletal proteins, and growth kinetics. The mitogenic effect of growth factors was assessed by incorporation of [3H]thymidine in the cellular DNA for 4 hours. Differences between groups of observations were assessed by the Student t-test. The morphogenic effects of growth factors were described with respect to growth pattern, cell orientation, and cell and nucleus form after a random photographic recording. The fibroblast-like cell type and the non-transformed phenotype of the cell line have been identified by the presence of parameters considered to be characteristic of a normal fibroblast-like cell line. The morphogenic analysis of both experimental and control cultures showed a monolayer of adherent cells with spindle or stellate morphology, a random alignment and round or elongated nuclei. Incorporation of [3H]-thymidine was increased in a dose-dependent manner by all growth factors. Maximal effect on the DNA synthesis was: rEGF, 131%; nPDGF, 274%; and nFGF, 182%.(ABSTRACT TRUNCATED AT 250 WORDS)

Blom, S; Holmstrup, P

1994-01-01

149

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

International Nuclear Information System (INIS)

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 Ca2+Cao2+ has been implicated in osteogenesis by stimulating the proliferation and differentiation of osteoblasts; however, the role of Cao2+ signaling in odontogenesis remains unclear. We found that elevated Cao2+ 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 Ca2+ 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 Ca2+ channels inhibitor, nifedipine. However, pretreatment with nifedipine had no effect on ERK1/2 phosphorylation triggered by Ca2+, suggesting that the Ca2+ influx from Ca2+ channels may operate independently of ERK signaling. Dental pulp cells do not express the transcript of Ca2+-sensing receptors (CaSR) and only respond slightly to other cations such as Sr2+ and spermine, suggesting that dental pulp cells respond to Cao2+ to increase BMP-2 mRNA expression in a manner different from CaSR and rather specific for Cao2+ among cations.

150

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

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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

151

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

152

Treatment of lateral periodontal cyst with guided tissue regeneration  

OpenAIRE

Lateral periodontal cyst (LPC), originated from epithelial rests in the periodontal ligament, is a noninflammatory cyst on the lateral surface of the root of a vital tooth. LPC is generally asymptomatic and presents a round or oval uniform lucency with well-defined borders radiographically. In this case report, clinical, histological and radiographical findings and periodontal treatment of 32-year-old female patient, who was referred to Department of Periodontology Clinic of Faculty of Dentis...

Meseli, Suleyman Emre; Agrali, Omer Birkan; Peker, Onder; Kuru, Leyla

2014-01-01

153

Chronic stress enhances progression of periodontitis via ?1-adrenergic signaling: a potential target for periodontal disease therapy  

OpenAIRE

This study assessed the roles of chronic stress (CS) in the stimulation of the sympathetic nervous system and explored the underlying mechanisms of periodontitis. Using an animal model of periodontitis and CS, the expression of tyrosine hydroxylase (TH) and the protein levels of the ?1-adrenergic receptor (?1-AR) and ?2-adrenergic receptor (?2-AR) were assessed. Furthermore, human periodontal ligament fibroblasts (HPDLFs) were stimulated with lipopolysaccharide (LPS) to mimic the process ...

Lu, Huaixiu; Xu, Minguang; Wang, Feng; Liu, Shisen; Gu, Jing; Lin, Songshan

2014-01-01

154

Types of Periodontal Disease  

Science.gov (United States)

... can lead to a more serious form of periodontal disease, called periodontitis. Gingivitis can be reversed with a combination of ... may need other steps, such as antimicrobial therapy, periodontal surgery or both. ... Aggressive periodontitis gets worse faster than chronic periodontitis. ...

155

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

156

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

157

Periodontal Treatments and Procedures  

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... Comprehensive Periodontal Evaluation Periodontal Treatments and Procedures Non-Surgical Periodontal Treatments Gum Graft Surgery Laser Treatment for Gum Disease Regenerative Procedures Dental Crown ...

158

Periodontal Plastic Surgery Procedures  

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... Comprehensive Periodontal Evaluation Periodontal Treatments and Procedures Non-Surgical Periodontal Treatments Gum Graft Surgery Laser Treatment for Gum Disease Regenerative Procedures Dental Crown ...

159

Periodontal regeneration using engineered bone marrow mesenchymal stromal cells.  

Science.gov (United States)

Regeneration of lost periodontium is a challenge in that both hard (alveolar bone, cementum) and soft (periodontal ligament) connective tissues need to be restored to their original architecture. Bone marrow mesenchymal stromal cells (BM-MSCs) appear to be an attractive candidate for connective tissue regeneration. We hypothesized that BM-MSCs are able to sense biological cues from the local microenvironment and organize appropriately to contribute to the regeneration of both soft and hard periodontal connective tissues. To test this hypothesis, we transplanted GFP(+) rat BM-MSCs expanded ex vivo on microcarrier gelatin beads into a surgically created rat periodontal defect. After three weeks, evidence of regeneration of bone, cementum and periodontal ligament was observed in both transplanted and control animals. However, the animals that received BM-MSCs regenerated significantly greater new bone. In addition, the animals that had received the cells and beads transplant had significantly more appropriately orientated periodontal ligament fibers, indicative of functional restoration. Finally, donor-derived BM-MSCs were found integrated in newly formed bone, cementum and periodontal ligament, suggesting that they can directly contribute to the regeneration of cells of these tissues. PMID:20832109

Yang, Yi; Rossi, Fabio M V; Putnins, Edward E

2010-11-01

160

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

161

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

162

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

Scientific Electronic Library Online (English)

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 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.

163

Combination of aligned PLGA/Gelatin electrospun sheets, native dental pulp extracellular matrix and treated dentin matrix as substrates for tooth root regeneration.  

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In tissue engineering, scaffold materials provide effective structural support to promote the repair of damaged tissues or organs through simulating the extracellular matrix (ECM) microenvironments for stem cells. This study hypothesized that simulating the ECM microenvironments of periodontium and dental pulp/dentin complexes would contribute to the regeneration of tooth root. Here, aligned PLGA/Gelatin electrospun sheet (APES), treated dentin matrix (TDM) and native dental pulp extracellular matrix (DPEM) were fabricated and combined into APES/TDM and DPEM/TDM for periodontium and dental pulp regeneration, respectively. This study firstly examined the physicochemical properties and biocompatibilities of both APES and DPEM in vitro, and further investigated the degradation of APES and revascularization of DPEM in vivo. Then, the potency of APES/TDM and DPEM/TDM in odontogenic induction was evaluated via co-culture with dental stem cells. Finally, we verified the periodontium and dental pulp/dentin complex regeneration in the jaw of miniature swine. Results showed that APES possessed aligned fiber orientation which guided cell proliferation while DPEM preserved the intrinsic fiber structure and ECM proteins. Importantly, both APES/TDM and DPEM/TDM facilitated the odontogenic differentiation of dental stem cells in vitro. Seeded with stem cells, the sandwich composites (APES/TDM/DPEM) generated tooth root-like tissues after being transplanted in porcine jaws for 12 w. In dental pulp/dentin complex-like tissues, columnar odontoblasts-like layer arranged along the interface between newly-formed predentin matrix and dental pulp-like tissues in which blood vessels could be found; in periodontium complex-like tissues, cellular cementum and periodontal ligament (PDL)-like tissues were generated on the TDM surface. Thus, above results suggest that APES and DPEM exhibiting appropriate physicochemical properties and well biocompatibilities, in accompany with TDM, could make up an ECM microenvironment for tooth root regeneration, which also offers a strategy for complex tissue or organ regeneration. PMID:25818413

Chen, Gang; Chen, Jinlong; Yang, Bo; Li, Lei; Luo, Xiangyou; Zhang, Xuexin; Feng, Lian; Jiang, Zongting; Yu, Mei; Guo, Weihua; Tian, Weidong

2015-06-01

164

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 chewing cycle might...

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

2012-01-01

165

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

166

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

167

Proliferation and tube formation of periodontal endothelial cells.  

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Angiogenesis is indispensable to guide a regeneration of good periodontal tissue in the wound healing after periodontal surgery. Hepatocyte growth factor is well known for a strong angiogenic factor and it may play important roles in the periodontal tissue during periodontal wound healing. In exploring the promotion of angiogenesis in the periodontal ligament, proliferative and tubulogenic responses of endothelial cells to hepatocyte growth factor and to soluble factors secreted by fibroblasts were investigated. Pavement-shaped cells isolated from a human periodontal ligament were identified as the endothelial cell by their granular immunoreactivity for factor VIII. The proliferation of the endothelial cells was accelerated by the addition of hepatocyte growth factor or fibroblast-conditioned medium, and far more by adding both than either. The endothelial cells seeded on the agar containing both hepatocyte growth factor and fibroblast products formed a dense network in a shorter time than on the agar containing either. The endothelial cells in the dense network took a tube-like structure with lumen and were covered with laminin. These results suggest that hepatocyte growth factor administered into the regenerating periodontal tissue may promote, synergistically with local factors produced by the activated fibroblast, the proliferation and tubulogenesis of the remaining endothelial cells. PMID:16146206

Sato, Etsuko; Hashimoto, Hisashi; Kamoi, Hisahiro; Tachibana, Toshiaki; Ishikawa, Hiroshi; Kamoi, Kyuichi

2005-06-01

168

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

169

Periodontal Disease and Systemic Health  

Science.gov (United States)

... Comprehensive Periodontal Evaluation Periodontal Treatments and Procedures Non-Surgical Periodontal Treatments Gum Graft Surgery Laser Treatment for Gum Disease Regenerative Procedures Dental Crown ...

170

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

171

Immunohistochemical expression of heat shock proteins in the mouse periodontal tissues due to orthodontic mechanical stress*  

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Full Text Available Abstract The histopathology of periodontal ligament of the mouse subjected to mechanical stress was studied. Immunohistochemical expressions of HSP27 and pHSP27 were examined. Experimental animals using the maxillary molars of ddY mouse by Waldo method were used in the study. A separator was inserted to induce mechanical stress. After 10 minutes, 20 minutes, 1 hour, 3 hours, 9 hours and 24 hours, the regional tissues were extracted, fixed in 4% paraformaldehyde and 0.05 M phosphate-buffered fixative solution. Paraffin sections were made for immunohistochemistry using HSP27 and p-HSP27. In the control group, the periodontal ligament fibroblasts expressed low HSP27 and p-HSP27. However, in the experimental group, periodontal ligament fibroblasts expressed HSP27 10 minutes after mechanical load application in the tension side. The strongest expression was detected 9 hours after inducing mechanical load. p-HSP27 was also expressed in a time-dependent manner though weaker than HSP27. The findings suggest that HSP27 and p-HSP27 were expressed for the maintenance of homeostasis of periodontal ligament by the activation of periodontal ligament fibroblasts on the tension side. It also suggests that these proteins act as molecular chaperones for osteoblast activation and maintenance of homeostasis.

Muraoka R

2010-11-01

172

Influence of periodontitis and nonsurgical periodontal intervention on atherosclerosis diseases  

OpenAIRE

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 non...

Tielou Chen; Shifeng Wang; Guoqin Liu; Xinhai Zhang; Dahai Tang; Zhifen Wu

2012-01-01

173

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

174

Mini Review: The Epithelial Cell Rests of Malassez: A Role in Periodontal Regeneration?  

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Full Text Available This article reviews general aspects about the epithelial cell rests of Malassez (ERM. The historical and general morphological features of the ERM are briefly described. The embryological derivation of the ERM is presented as an important consideration in understanding the events associated with their origin and possible functional roles within the periodontal ligament. The ultrastructural description of the ERM is also included to complement the morphological characteristics which distinguish these cells as the unique epithelial element of the periodontal ligament. The unique ability of these cells to synthesize and secrete a number of proteins usually associated with cells of mesenchymal origin, rather than ectodermal origin. Such considerations lead to our hypothesis that one of the functional roles of the ERM may lie not only their role in maintaining and contributing to the normal periodontal cellular elements and function but also contributing, in a significant manner, to periodontal regeneration.

Julio C. Rincón

2009-12-01

175

Immunohistochemical detection of nestin in the periodontal Ruffini endings of the rat incisor.  

Science.gov (United States)

Nestin is an intermediate filament which was first identified in neuroepithelial stem cells. This expression has also been reported in restricted locations in adults. Previous studies have suggested that the periodontal Ruffini endings remain immature in nature even in adulthood. The present study reports on a characteristic expression of immunoreaction for nestin in the periodontal Ruffini endings during postnatal development. RT-PCR analysis detected nestin mRNA in a reverse transcripted cDNA sample from both the rat trigeminal ganglion and periodontal ligament. The nestin immunoreaction existed in the periodontal ligament at postnatal day 3 (PO 3 days), when many spindle-shaped Schwann cells were positive for nestin immunoreaction. At PO 1 week, when periodontal nerve fibers displayed a dendritic fashion, the round cells came to show the nestin immunoreaction. These immunopositive cells were also reactive for S-100 protein and non-specific cholinesterase, indicating that these cells could be categorized as terminal Schwann cells associated with the periodontal Ruffini endings. Some ordinary Schwann cells also exhibited nestin immunoreaction. From PO 2 to 3 weeks, nestin positive terminal Schwann cells increased in number in accordance with the postnatal development of the periodontal Ruffini endings, while this immuno-expression pattern remained unchanged. Nestin immunoreaction was also recognizable in the satellite cells - but never in the neurons - in the trigeminal ganglion throughout this observation period. This immuno-expression pattern suggests that nestin serves as an intermediate filament for mechanical stability in the periodontal Ruffini endings against external stimuli. PMID:19013217

Saito, Shion; Suzuki, Akiko; Nozawa-Inoue, Kayoko; Kawano, Yoshiro; Hoshino, Masaaki; Saito, Chikara; Maeda, Takeyasu

2009-01-16

176

Pro-oxidant status and matrix metalloproteinases in apical lesions and gingival crevicular fluid as potential biomarkers for asymptomatic apical periodontitis and endodontic treatment response  

OpenAIRE

Abstract Background Oxidative stress and matrix metalloproteinases -9 and -2 are involved in periodontal breakdown, whereas gingival crevicular fluid has been reported to reflect apical status. The aim of this study was to characterize oxidant balance and activity levels of MMP -2 and -9 in apical lesions and healthy periodontal ligament; and second, to determine whether potential changes in oxidant balance were reflected in gingival crevicular fluid from asymptomatic apical periodontitis (AA...

Dezerega Andrea; Madrid Sonia; Mundi Verónica; Valenzuela María A; Garrido Mauricio; Paredes Rodolfo; García-Sesnich Jocelyn; Ortega Ana V; Gamonal Jorge; Hernández Marcela

2012-01-01

177

Lateral collateral ligament (image)  

Science.gov (United States)

The lateral collateral ligament connects the end of the femur (thigh) to the top of the fibula (the thin ... that runs next to the shin bone). The lateral collateral ligament provides stability against varus stress. Varus ...

178

Anterior cruciate ligament (ACL  

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Full Text Available The anterior cruciate ligament or ACL (ligamentum cruciatum anterius is often injured, either alone or within complex ligament injuries of the knee. Therefore, the knowledge of detailed anatomic (macro- and micro-morphological characteristics of this ligament is of key importance in therapy. The anatomy, structure, insertions, vascularization and innervations of the anterior cruciate ligament of the knee are described from the aspect of modern treatment and rehabilitation methods.

Slavkovi? Nemanja

2005-01-01

179

Ultrasonography of ankle ligaments  

International Nuclear Information System (INIS)

The lateral collateral ligament of the ankle is a complex of 3 ligaments: The anterior and posterior talofibular ligaments and the calcaneofibular ligament; these ligaments work together to support the lateral aspect of the ankle. The anterior talofibular (ATF) ligament (Fig. 1) runs from the anterior of the talus. The probe is placed in a slightly oblique position from the malleolus toward the forefoot. The ligament is hyperechoic when its fibres are perpendicular to the ultrasound beam (anisotropy artifact is present in ligaments as well as in tendons). It is approximately 2 mm thick and, during examination, must be straight and tight from one insertion point to the other, as seen in Fig. 2. The posterior talofibular (PTF) ligament, which runs from the posterior part of the malleolus to the posterior part of the talus, is difficult to see on US, being partially or sometimes completely hidden by the malleolus. The calcaneofibular ligament forms the middle portion of the lateral collateral ligament. It is tight between the inferior part of the lateral malleolus and the calcaneus, and runs in a slightly posterior oblique direction toward the heel (Fig. 3). The ligament lies on the deep surface of the fibular tendons, forming a hammock to fall deep on the calcaneus surface (Fig. 4). The calcaneofibular ligament is approximately 2-3 nun thick and is hyperechoic in the distal two-thirds only because of the obliquity of the proximal part. When examining this ligament, it il part. When examining this ligament, it is mandatory that the ankle be flexed dorsally; this stretches the ligament so that it can be seen clearly. (author)

180

Diabetes and periodontitis  

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Full Text Available 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 mechanisms. The authors reviewed human epidemiological studies, cross-sectional observations and longitudinal cohort, case control that evaluated variables exclusively over the past 30 years and the predominant findings from the "certain" articles are summarized in this review. This review clarifies certain queries such as 1 Do periodontal diseases have an effect on the metabolic control of diabetes? 2 Does diabetes act as a risk factor of periodontitis? 3 What are the possible underlying mechanisms relating the connection between these two chronic diseases? 4 What is the effect of periodontal intervention on metabolic control of diabetes? After a thorough survey of literature, it was observed that diabetes acts as a risk factor in development of periodontitis as periodontitis is significantly aggravated in patients suffering from diabetes having long term hyperglycemia. Different mechanisms underlying the association between the accelerated periodontal disease and diabetes are emerging but still more work is required. Major efforts are required to elucidate the impact of periodontal diseases on diabetes. At the same time, patients are needed to be made aware of regular periodontal maintenance schedule and oral hygiene.

Deshpande Kalyani

2010-01-01

181

Cemental tear: a case report with nonsurgical periodontal therapy / Dilaceração cementária: relato de caso clínico com terapia periodontal não cirúrgica  

Scientific Electronic Library Online (English)

Full Text Available OBJETIVO: Relatar um caso de dilaceração cementária, uma condição periodontal rara caracterizada pela separação total ou parcial do cemento dental, abordando principalmente aspectos relativos ao seu diagnóstico e tratamento. DESCRIÇÃO DO CASO: Um homem de 50 anos procurou assistência odontológica qu [...] eixando-se de dor localizada no segundo molar inferior que apresentava profundidade de sondagem de 4 mm com presença de um corpo estranho no sulco gengival da face distal. O exame radiográfico demonstrou um fragmento radiopaco destacado da raiz. O fragmento foi removido sem cirurgia periodontal. O exame histopatológico demonstrou tratar-se de um fragmento de cemento com presença de lamelas cementárias, cementócitos e fibras do ligamento periodontal, confirmando o diagnóstico de dilaceração cementária. CONCLUSÃO: Após dois anos, o tratamento periodontal não cirúrgico demonstrou aspectos clínicos e radiográficos satisfatórios. Portanto, a terapia periodontal não cirúrgica pode ser uma modalidade de tratamento adequada e previsível para a dilaceração cementária. Abstract in english PURPOSE: To report a case of cemental tear, a rare periodontal condition characterized by total or partial separation of the dental cementum, mainly addressing issues related to its diagnosis and treatment. CASE DESCRIPTION: A 50 years-old man sought dental assistance complaining of pain located in [...] the mandibular left second premolar that showed a 4 mm probing depth with the presence of a foreign body in the distal gingival sulcus. Radiographic examination demonstrated a slight radiopaque fragment detached from the root. The fragment was removed without a periodontal flap. Histopathological examination was performed and evidenced the presence of a cementum fragment with cementum lamellae, cementocytes, and adhered periodontal ligament fibers, confirming the diagnosis of cemental tear. CONCLUSION: After a follow-up of 2 years, the nonsurgical periodontal therapy showed satisfactory clinical and radiographic outcome. Therefore, this approach should be a suitable and predictable treatment modality for the cemental tear.

Leonardo Silveira, Damasceno; Walderez Ornelas, Dutra; Eder Gonçalves, Melgaço; Paulo Eduardo Alencar de, Souza; Elton Gonçalves, Zenóbio; Martinho Campolina Rebello, Horta.

182

Ultrasonography of ankle ligaments  

Energy Technology Data Exchange (ETDEWEB)

The lateral collateral ligament of the ankle is a complex of 3 ligaments: The anterior and posterior talofibular ligaments and the calcaneofibular ligament; these ligaments work together to support the lateral aspect of the ankle. The anterior talofibular (ATF) ligament (Fig. 1) runs from the anterior of the talus. The probe is placed in a slightly oblique position from the malleolus toward the forefoot. The ligament is hyperechoic when its fibres are perpendicular to the ultrasound beam (anisotropy artifact is present in ligaments as well as in tendons). It is approximately 2 mm thick and, during examination, must be straight and tight from one insertion point to the other, as seen in Fig. 2. The posterior talofibular (PTF) ligament, which runs from the posterior part of the malleolus to the posterior part of the talus, is difficult to see on US, being partially or sometimes completely hidden by the malleolus. The calcaneofibular ligament forms the middle portion of the lateral collateral ligament. It is tight between the inferior part of the lateral malleolus and the calcaneus, and runs in a slightly posterior oblique direction toward the heel (Fig. 3). The ligament lies on the deep surface of the fibular tendons, forming a hammock to fall deep on the calcaneus surface (Fig. 4). The calcaneofibular ligament is approximately 2-3 nun thick and is hyperechoic in the distal two-thirds only because of the obliquity of the proximal part. When examining this ligament, it is mandatory that the ankle be flexed dorsally; this stretches the ligament so that it can be seen clearly. (author)

Peetrons, P.A. [C.H. Moliere-Longchamp, Dept. of Radiology, Brussels (Belgium); Silvestre, A. [Hopital Militaire Laveran, Dept. of Radiology, Marseilles (France); Cohen, M. [Hoptial Saint-Joseph, Dept. of Radiology, Marseilles (France); Creteur, V. [C.H. Moliere-Longchamp, Dept. of Radiology, Brussels (Belgium)

2002-02-01

183

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

184

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

185

Chronic stress enhances progression of periodontitis via ?1-adrenergic signaling: a potential target for periodontal disease therapy.  

Science.gov (United States)

This study assessed the roles of chronic stress (CS) in the stimulation of the sympathetic nervous system and explored the underlying mechanisms of periodontitis. Using an animal model of periodontitis and CS, the expression of tyrosine hydroxylase (TH) and the protein levels of the ?1-adrenergic receptor (?1-AR) and ?2-adrenergic receptor (?2-AR) were assessed. Furthermore, human periodontal ligament fibroblasts (HPDLFs) were stimulated with lipopolysaccharide (LPS) to mimic the process of inflammation. The proliferation of the HPDLFs and the expression of ?1-AR and ?2-AR were assessed. The inflammatory-related cytokines interleukin (IL)-1?, IL-6 and IL-8 were detected after pretreatment with the ?1/?2-AR blockers phentolamine/propranolol, both in vitro and in vivo. Results show that periodontitis under CS conditions enhanced the expression of TH, ?1-AR and ?2-AR. Phentolamine significantly reduced the inflammatory cytokine levels. Furthermore, we observed a marked decrease in HPDLF proliferation and the increased expression of ?1-ARfollowing LPS pretreatment. Pretreatment with phentolamine dramatically ameliorated LPS-inhibited cell proliferation. In addition, the blocking of ?1-ARsignaling also hindered the upregulation of the inflammatory-related cytokines IL-1?, IL-6 and IL-8. These results suggest that CS can significantly enhance the pathological progression of periodontitis by an ?1-adrenergic signaling-mediated inflammatory response. We have identified a potential therapeutic target for the treatment of periodontal disease, particularly in those patients suffering from concurrent CS. PMID:25323788

Lu, Huaixiu; Xu, Minguang; Wang, Feng; Liu, Shisen; Gu, Jing; Lin, Songshan

2014-01-01

186

REINFORCING POTENTIAL OF JUTE PULP WITH TREMA ORIENTALIS (NALITA PULP  

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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

187

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

188

Terapia periodontal no quirúrgica / Nonsurgical periodontal therapy  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish INTRODUCCIÓN: en el tratamiento de las enfermedades periodontales contamos con la terapia periodontal no quirúrgica, la cual ha sido avalada científicamente mostrando su efectividad. El principal objetivo de este artículo es demostrar la efectividad de la terapia periodontal no quirúrgica evidenciad [...] a en múltiples estudios con relación a las indicaciones, aspectos microbiológicos, efectos en los tejidos y la importancia de la terapia de mantenimiento una vez finalizado el tratamiento. MÉTODOS: se hizo una revisión con relación al tema en los últimos años teniendo como patrón los conceptos clave periodontales. RESULTADOS: la terapia periodontal no quirúrgica (TPNQ) no es un procedimiento que pueda y deba realizarse en un corto tiempo y en pocas citas, el tiempo para su ejecución se amplía lo necesario en especial para lograr una limpieza y regularización de las raíces lo más completa posible. CONCLUSIÓN: varios autores reportan que la reducción de la microbiota se mantuvo entre 14 y 180 días, luego de la terapia, esto justifica las citas periódicas de mantenimiento periodontal y estos señalan que el aspecto crítico de la terapia no es la escogencia entre un procedimiento quirúrgico o no quirúrgico, sino la limpieza detallada y completa por el profesional y el buen nivel de higiene bucal por parte del paciente. Abstract in english INTRODUCTION: In the treatment of periodontal diseases, we can rely on nonsurgical periodontal therapy, which has been scientifically proven as its effectiveness has been recognized. The main objective of this article is to demonstrate the usefulness of nonsurgical periodontal therapy, as evidenced [...] in several studies that serve as guidelines, as well as microbiological aspects, effects on tissues and the importance of maintenance therapy after treatment completion. METHODS: a review was conducted in order to revise this topic considering key periodontal concepts as a guideline. RESULTS: nonsurgical periodontal therapy (NSPT) is a procedure that cannot and should not be carried out in a few sessions; the time required for its completion is extended as necessary in order to achieve cleaning and adjustment of the roots as completely as possible. CONCLUSIONS: Several authors have reported that reduction of microbiota remains between 14 and 180 days after therapy. This explains the regular periodontal maintenance appointments. They also indicate that the critical aspect of this therapy is not the choice between a surgical or a nonsurgical procedure, but a detailed and thorough cleaning by the dental professional and the good level of oral hygiene achieved by the patient.

Leticia, Botero Zuluaga; Alejandro, Botero Botero; Juán Sebastián, Bedoya Trujillo; Isabel Cristina, Guzmán Zuluaga.

2012-06-01

189

Ankle ligament injuries.  

OpenAIRE

Acute ankle ligament sprains are common injuries. The majority of these occur during athletic participation in the 15 to 35 year age range. Despite the frequency of the injury, diagnostic and treatment protocols have varied greatly. Lateral ligament complex injuries are by far the most common of the ankle sprains. Lateral ligament injuries typically occur during plantar flexion and inversion, which is the position of maximum stress on the anterotalofibular liagment (ATFL). For this reason, th...

Renstro?m, Per A. F. H.; Lynch, Scott A.

1997-01-01

190

Determinantes del diagnóstico periodontal / Determinants of periodontal diagnosis  

Scientific Electronic Library Online (English)

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 diagnós [...] tico 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. Abstract in english 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 perfo [...] rmed analysis of the clinical expression of the disease, from gingivitis to periodontitis. This article reviews the most important determinants of periodontal diagnosis.

JE, Botero; E, Bedoya.

2010-08-01

191

Periodontal disease in smokers  

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Full Text Available Tobacco contains about 4000 different toxic substances from which almost 40 are proven to be cancerogenic. Nicotine, toxic alkaloid, is the most active substance in tobacco causing major number of harmful consequences for human organism as a whole, and for periodontal tissues as well. The aim of the paper was to show harmful effects of smoking on periodontal disease development, and to point out the problems caused by smoking during and after the periodontal treatment. Periodontal disease occurs in smokers more frequently as opposed to non-smokers. Typically, smokers have lower level of gingival inflammation, more excessive and accelerated loss of alveolar bone and epithelial insertion, deeper periodontal pockets and numerous gingival recessions. Along with that, smokers are carrying a decreased immune response that is expressed through various defense mechanisms. Smoking has negative impact on the outcome of conservative and surgical periodontal therapy. Effects of smoking on periodontal therapy success rate are requiring administration of antiseptic solutions and antibiotics throughout the treatment course. Every periodontologist must influence patients to stop smoking and thus act preventively on occurrence and progress of periodontal disease.

Cerovi? Olivera

2005-01-01

192

Periodontitis associated with osteomalacia.  

Science.gov (United States)

Osteomalacia is a metabolic bone disorder characterized by an alternation of bone mineralization, bone pain, increased bone fragility and fractures. A 23-year-old female patient reported with short stature and depressed nasal bridge with oral manifestation showing partial anodontia and periodontitis. This case report attempt to highlights clinical, radiographic, biochemical features of osteomalacia and periodontitis. PMID:25425827

Wankhede, Anand Narayanrao; Sayed, Arshad Jamal; Gattani, Deepti Rakesh; Bhutada, Girish Parashram

2014-09-01

193

Periodontitis associated with osteomalacia  

OpenAIRE

Osteomalacia is a metabolic bone disorder characterized by an alternation of bone mineralization, bone pain, increased bone fragility and fractures. A 23-year-old female patient reported with short stature and depressed nasal bridge with oral manifestation showing partial anodontia and periodontitis. This case report attempt to highlights clinical, radiographic, biochemical features of osteomalacia and periodontitis.

Wankhede, Anand Narayanrao; Sayed, Arshad Jamal; Gattani, Deepti Rakesh; Bhutada, Girish Parashram

2014-01-01

194

[Microflora of periodontal pockets in advanced periodontitis].  

Science.gov (United States)

The aim of study was the evaluation of periodontal pockets microflora in patients with advanced periodontitis. From each subject 16-20 samples were taken using paper points. Pooled sample after 60 s. mixing was serially diluted in reduced BHI. For total cell counts and for the isolation of black pigmented anaerobes Brucella agar supplemented with 5% sheep blood, hemin, menadione, with and without Kanamycin-Vancomycin mixture and BM agar plates were used. For isolation of A. actinomycetemcomitans TSBV agar plates were used. Cultures were incubated in anaerobic chamber at 37 degrees C for 7 days and TSBV agar plates in an atmosphere of 95% air-5% CO2 at 37 degrees C for 5 days. Microorganisms were identified by Gram staining, colony morphology, fluorescence in UV-light, haemagglutination of 3% sheep erythrocytes, fermentation of sugars, production of indole, urease (API 20A), specific enzymes (Rapid ID 32A). Twenty seven subjects with clinically recognized periodontitis were examined. Microorganisms important in periodontitis were isolated from periodontal pockets of almost all examined subjects. The number of bacteria obtained from the sample of one patient ranged from 1 x 10(4) CFU/ml to 3,6 x 10(6) CFU/ml. Porphyromonas gingivalis was identified in the samples taken from 17 patients, Prevotella intermedia-19, Actinobacillus actinomycetemcomitans -11, Fusobacterium nucleatum-9, Peptostreptococcus spp.-22. PMID:9411079

Sawicka-Grzelak, A; Meisel-Miko?ajczyk, F; S?otwi?ska, S M; Wierzbicka, M

1997-01-01

195

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

196

Treatment of lateral periodontal cyst with guided tissue regeneration.  

Science.gov (United States)

Lateral periodontal cyst (LPC), originated from epithelial rests in the periodontal ligament, is a noninflammatory cyst on the lateral surface of the root of a vital tooth. LPC is generally asymptomatic and presents a round or oval uniform lucency with well-defined borders radiographically. In this case report, clinical, histological and radiographical findings and periodontal treatment of 32-year-old female patient, who was referred to Department of Periodontology Clinic of Faculty of Dentistry, Marmara University with a painless hyperplastic lesion on the distobuccal site of the tooth number 12, were presented. The tooth number 12 was vital and a well-defined round radiolucent area with corticated borders was determined radiographically. Preliminary diagnosis was LPC based on clinical and radiographical findings. Mechanical periodontal treatment consisted of oral hygiene instructions, scaling and root planing was applied and flap operation was performed to gain access to the lesion. Following enucleation of the lesion, alveolar bone destruction shaped as a tunnel from labial to palatinal site was observed. The bone cavity was grafted with bovine-derived xenograft, followed by placement of a resorbable collagen membrane. Tissues removed from of the lesion were examined histologically. Hematoxylen-eosin stained sections showed vasculature granulomatous structure underlying squamous epithelium, and destructed bone spaces, all of which were consisted with LPC. Acceptable clinical healing was achieved at 6 months follow-up period. Satisfactory clinical and radiographical outcome can be achieved in the treatment of LPC using regenerative periodontal approach. PMID:25202227

Meseli, Suleyman Emre; Agrali, Omer Birkan; Peker, Onder; Kuru, Leyla

2014-07-01

197

Tabaquismo y enfermedad periodontal  

Scientific Electronic Library Online (English)

Full Text Available 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

198

Tabaquismo y enfermedad periodontal  

Directory of Open Access Journals (Sweden)

Full Text Available 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 necesidad 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.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 community 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

2002-06-01

199

Refining of Polysulfide Pulps  

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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

200

Biomaterials for promoting periodontal regeneration in human intrabony defects: a systematic review.  

Science.gov (United States)

Intrabony periodontal defects are a frequent complication of periodontitis and, if left untreated, may negatively affect long-term tooth prognosis. The optimal outcome of treatment in intrabony defects is considered to be the absence of bleeding on probing, the presence of shallow pockets associated with periodontal regeneration (i.e. formation of new root cementum with functionally orientated inserting periodontal ligament fibers connected to new alveolar bone) and no soft-tissue recession. A plethora of different surgical techniques, often including implantation of various types of bone graft and/or bone substitutes, root surface demineralization, guided tissue regeneration, growth and differentiation factors, enamel matrix proteins or various combinations thereof, have been employed to achieve periodontal regeneration. Despite positive observations in animal models and successful outcomes reported for many of the available regenerative techniques and materials in patients, including histologic reports, robust information on the degree to which reported clinical improvements reflect true periodontal regeneration does not exist. Thus, the aim of this review was to summarize, in a systematic manner, the available histologic evidence on the effect of reconstructive periodontal surgery using various types of biomaterials to enhance periodontal wound healing/regeneration in human intrabony defects. In addition, the inherent problems associated with performing human histologic studies and in interpreting the results, as well as certain ethical considerations, are discussed. The results of the present systematic review indicate that periodontal regeneration in human intrabony defects can be achieved to a variable extent using a range of methods and materials. Periodontal regeneration has been observed following the use of a variety of bone grafts and substitutes, guided tissue regeneration, biological factors and combinations thereof. Combination approaches appear to provide the best outcomes, whilst implantation of alloplastic material alone demonstrated limited, to no, periodontal regeneration. PMID:25867987

Sculean, Anton; Nikolidakis, Dimitris; Nikou, George; Ivanovic, Aleksandar; Chapple, Iain L C; Stavropoulos, Andreas

2015-06-01

201

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

202

Non surgical Periodontal Therapy  

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Full Text Available Periodontal disease is the number one chronic infectious disease in the world. It is the leading cause of tooth loss, and begins as painless infection in the gums that is caused by buildup of bacterial plaque. The treatment modalities that exist for the treatment of gingivitis and Periodontitis depends on the extent and severity, but the primary objective is to restore the gingival health by removing the local factors viz plaque, calculus etc. that provoke inflammation. Non- surgical periodontal therapy or NSPT is one of the management of gingival infection with scaling, root planning, antibiotics and other non surgical means.

Harinath Reddy S

2009-12-01

203

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.)

204

CT appearance of pulmonary ligament  

International Nuclear Information System (INIS)

Pulmonary ligament consists of 2 serosal of pleura that connect the lower to the mediastinum. Author analyse and present CT appearance of pulmonary ligament of the 40 normal and abnormal patients on the basis of anatomic knowledge from the cross section of cadaver. Left pulmonary ligament is more frequency visualized than the right. The most important CT landmark in localizing pulmonary ligament is the esophagus where the ligament attaches on its lateral wall. Pitfalls in CT identification of pulmonary ligament are right phrenic nerve and right pericardiacophrenic vessels which emerge from lateral wall of the IVC and wall of the emphysematous bulla in the region of the pulmonary ligament

205

Synchrotron radiation analysis of possible correlations between metal status in human cementum and periodontal disease  

Energy Technology Data Exchange (ETDEWEB)

Periodontitis is a serious disease that affects up to 50% of an adult population. It is a chronic condition involving inflammation of the periodontal ligament and associated tissues leading to eventual tooth loss. Some evidence suggests that trace metals, especially zinc and copper, may be involved in the onset and severity of periodontitis. Thus we have used synchrotron X-ray fluorescence imaging on cross sections of diseased and healthy teeth using a microbeam to explore the distribution of trace metals in cementum and adhering plaque. The comparison between diseased and healthy teeth indicates that there are elevated levels of zinc, copper and nickel in diseased teeth as opposed to healthy teeth. This preliminary correlation between elevated levels of trace metals in the cementum and plaque of diseased teeth suggests that metals may play a role in the progress of periodontitis.

Martin, R.R.; Naftel, S.J.; Nelson, A.J.; Edwards, M.; Mithoowani, H.; Stakiw, J. (UWO); (Saskatchewan)

2010-03-16

206

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)

207

Periodontal probing: a review.  

Science.gov (United States)

Periodontal probes are the main instruments that are used to assess the status of the periodontium, either for screening purposes or to evaluate periodontal changes throughout the treatment process. With increased knowledge and understanding of periodontal disease, the probes have evolved from a unidimensional manual shape into a more sophisticated computerised instrument. This is due to the need to increase the accuracy and reproducibility of readings and to improve efficiency (time, effort, money). Each probe has characteristic features that makes it unique and, in some cases, specific and limited to use. The aim of this paper is to present a brief introduction to periodontal disease and the methodology of measuring it, followed by probing limitations. The paper will also discuss the methodology of reducing probing error, examiner calibration and probing reproducibility. PMID:25198634

Al Shayeb, Kwthar Nassar A; Turner, Wendy; Gillam, David G

2014-08-01

208

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)

209

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

210

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

211

Risk Factors for Periodontitis  

OpenAIRE

In recent years, it has become apparent that the pathogenesis of periodontal diseases is more complex than the presence of virulent microorganisms. In fact, it is now widely accepted that susceptibility to periodontitis varies greatly between individuals who harbor the same, pathogenic microflora. To date, the bulk of evidence points to the host response to bacterial challenge as a major determinant of susceptibility. In this review, we will assess the data implicating various inherited and a...

Dyke, Thomas E.; Dave, Sheilesh

2005-01-01

212

Complement and Periodontitis  

OpenAIRE

Although the complement system is centrally involved in host defense, its overactivation or deregulation (e.g., due to inherent host genetic defects or due to pathogen subversion) may excessively amplify inflammation and contribute to immunopathology. Periodontitis is an oral infection-driven chronic inflammatory disease which exerts a systemic impact on health. This paper reviews evidence linking complement to periodontal inflammation and pathogenesis. Clinical and histological observations ...

Hajishengallis, George

2010-01-01

213

REINFORCING POTENTIAL OF JUTE PULP WITH TREMA ORIENTALIS (NALITA) PULP  

OpenAIRE

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. ...

Sabina Rawshan; Sarwar Jahan, M.

2009-01-01

214

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

215

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.

216

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

217

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

Scientific Electronic Library Online (English)

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 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

218

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

219

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

220

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)

221

Bone Grafts (Periodontal Regenerative Surgery)  

Science.gov (United States)

... for the gum disease called periodontitis . People with periodontitis lose gum coverage and bone support around their teeth. Regenerative surgery regrows these lost tissues. Preparation Before your surgery, you need to have basic periodontal treatment called scaling and root planing. You also ...

222

Formas agudas de periodontitis / Acute conditions of periodontal disease  

Scientific Electronic Library Online (English)

Full Text Available La clasificación de las Enfermedades Periodontales ha cambiado en las últimas décadas. En la clasificación la AAP de 1989 la periodontitis necrotizante ocupaba el cuarto lugar. En el Workshop Europeo de 1993 la periodontitis necrotizante aparece en el grupo de los descriptores primarios. Según el In [...] ternacional Workshop for a Classification of Periodontal Diseases and Conditions 1999 en el que se revisó y se modificó la clasificación de las patologías periodontales, las enfermedades periodontales necrotizantes ocupan el punto cinco, diferenciándose entre Gingivitis Necrotizante y Periodontitis Necrotizante. Y se añade en la clasificación el grupo de abscesos periodontales. En este artículo de revisión vamos a profundizar acerca de las formas agudas de periodontitis. Abstract in english The Periodontal Diseases classification had changed in the last decades. In AAP classification of 1989 the necrotize was in the 4th position. In the European Workshop was in the group of primary descriptors. According to the International Workshop for a Classification of Periodontal Diseases and Con [...] ditions 1999, review and modificated the classification of periodontal pathologies, the periodontal necrotize diseases are in the 5th position, distinguishing between Necrotize Gingivitis and Necrotize Periodontitis. And Peridontal Abscesses was add to the classification. In this paper we are going to review about the acute forms of Periodontal Diseases.

L., Pérez-Salcedo; A., Bascones-Martínez.

2008-04-01

223

Posterior cruciate ligament (PCL) injury  

Science.gov (United States)

Cruciate ligament injury - posterior; PCL injury; Knee injury - posterior cruciate ligament (PCL); Hyperextended knee ... a physical examination to check for signs of PCL injury. This includes moving the knee joint in ...

224

Ankle ligament injuries  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Acute ankle ligament sprains are common injuries. The majority of these occur during athletic participation in the 15 to 35 year age range. Despite the frequency of the injury, diagnostic and treatment protocols have varied greatly. Lateral ligament complex injuries are by far the most common of the [...] ankle sprains. Lateral ligament injuries typically occur during plantar flexion and inversion, which is the position of maximum stress on the anterotalofibular liagment (ATFL). For this reason, the ATFL is the most commonly torn ligament during an inversion injury. In more severe inversion injuries the calcaneofibular (CFL), posterotalofibular (PTFL) and subtalar ligament can also be injured. Most acute lateral ankle ligament injuries recover quickly with nonoperative management. The treatment program, called "functional treatment," includes application of the RICE principle (rest, ice, compression, and elevation) immediately after the injury, a short period of immobilization and protection with an elastic or inelastic tape or bandage, and early motion exercises followed by early weight bearing and neuromuscular ankle training. Proprioceptive training with a tilt board is commenced as soon as possible, usually after 3 to 4 weeks. The purpose is to improve the balance and neuromuscular control of the ankle. Sequelae after ankle ligament injuries are very common. As much as 10% to 30% of patients with a lateral ligament injury may have chronic symptoms. Symptoms usually include persistent synovitis or tendinitis, ankle stiffness, swelling, and pain, muscle weakness, and frequent giving-way. A well designed physical therapy program with peroneal strengthening and proprioceptive training, along with bracing and/or taping can alleviate instability problems in most patients. For cases of chronic instability that are refractory to bracing and external support, surgical treatment can be explored. If the chronic instability is associated with subtalar instability that is refractory to conservative measures and bracing as outlined above, surgical treatment must address the subtalar joint as well. Subtalar ligament injury and instability are probably more common than appreciated. Definition and diagnosis of this entity are difficult, however. Fortunately, it appears that in the majority of the acute injuries healing occurs with the same functional rehabilitation program as that for lateral ankle ligament sprains. For chronic subtalar instability an intial attempt at functional rehabilitation with ankle proprioceptive training and bracing should be attempted. If this program fails primary repair or reconstruction can be beneficial. Reconstructive procedures must address the subtalar joint. Subtalar instability often occurs in conjunction with talocrural instability, so careful diagnosis is critical in anyone with chronic ankle instability. If either is not addressed, the patient will continue to have problems. Deltoid ligament injuries most often occur in association with ankle fractures. They are rare as isolated injuries. If no fracture is evident on radiographs, particular attention must be paid to the syndesmosis to ensure there is not an associated syndesmosis disruption. True isolated deltoid injuries seem to do well with non-operative functional treatment as for lateral ankle ligament injuries. Deltoid ruptures associated with ankle fractures appear to heal well by addressing the other injuries and allowing the deltoid to heal on its own. It is vital to correct any syndesmosis injury and to obtain correct bony alignment. Syndesmosis injuries can be debilitating if not treated properly. Careful physical exam and interpretation of radiographs is necessary to obtain a correct diagnosis. Partial injuries appear to do well with functional rehabilitation. However, complete tears, if widening is not corrected, can lead to chronic ankle pain and early degenerative changes. Widening of the syndesmosis with a tear of the inferior tibiofibular ligaments is an ind

Per A.F.H., Renström; Scott A., Lynch.

1998-06-01

225

Ankle ligament injuries  

Directory of Open Access Journals (Sweden)

Full Text Available Acute ankle ligament sprains are common injuries. The majority of these occur during athletic participation in the 15 to 35 year age range. Despite the frequency of the injury, diagnostic and treatment protocols have varied greatly. Lateral ligament complex injuries are by far the most common of the ankle sprains. Lateral ligament injuries typically occur during plantar flexion and inversion, which is the position of maximum stress on the anterotalofibular liagment (ATFL. For this reason, the ATFL is the most commonly torn ligament during an inversion injury. In more severe inversion injuries the calcaneofibular (CFL, posterotalofibular (PTFL and subtalar ligament can also be injured. Most acute lateral ankle ligament injuries recover quickly with nonoperative management. The treatment program, called "functional treatment," includes application of the RICE principle (rest, ice, compression, and elevation immediately after the injury, a short period of immobilization and protection with an elastic or inelastic tape or bandage, and early motion exercises followed by early weight bearing and neuromuscular ankle training. Proprioceptive training with a tilt board is commenced as soon as possible, usually after 3 to 4 weeks. The purpose is to improve the balance and neuromuscular control of the ankle. Sequelae after ankle ligament injuries are very common. As much as 10% to 30% of patients with a lateral ligament injury may have chronic symptoms. Symptoms usually include persistent synovitis or tendinitis, ankle stiffness, swelling, and pain, muscle weakness, and frequent giving-way. A well designed physical therapy program with peroneal strengthening and proprioceptive training, along with bracing and/or taping can alleviate instability problems in most patients. For cases of chronic instability that are refractory to bracing and external support, surgical treatment can be explored. If the chronic instability is associated with subtalar instability that is refractory to conservative measures and bracing as outlined above, surgical treatment must address the subtalar joint as well. Subtalar ligament injury and instability are probably more common than appreciated. Definition and diagnosis of this entity are difficult, however. Fortunately, it appears that in the majority of the acute injuries healing occurs with the same functional rehabilitation program as that for lateral ankle ligament sprains. For chronic subtalar instability an intial attempt at functional rehabilitation with ankle proprioceptive training and bracing should be attempted. If this program fails primary repair or reconstruction can be beneficial. Reconstructive procedures must address the subtalar joint. Subtalar instability often occurs in conjunction with talocrural instability, so careful diagnosis is critical in anyone with chronic ankle instability. If either is not addressed, the patient will continue to have problems. Deltoid ligament injuries most often occur in association with ankle fractures. They are rare as isolated injuries. If no fracture is evident on radiographs, particular attention must be paid to the syndesmosis to ensure there is not an associated syndesmosis disruption. True isolated deltoid injuries seem to do well with non-operative functional treatment as for lateral ankle ligament injuries. Deltoid ruptures associated with ankle fractures appear to heal well by addressing the other injuries and allowing the deltoid to heal on its own. It is vital to correct any syndesmosis injury and to obtain correct bony alignment. Syndesmosis injuries can be debilitating if not treated properly. Careful physical exam and interpretation of radiographs is necessary to obtain a correct diagnosis. Partial injuries appear to do well with functional rehabilitation. However, complete tears, if widening is not corrected, can lead to chronic ankle pain and early degenerative changes. Widening of the syndesmosis with a tear of the inferior tibiofibular ligaments is an indication for surgery to place a syndesmosis screw for reduction o

Per A.F.H. Renström

1998-06-01

226

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

227

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.

228

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

229

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

230

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

231

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

232

Periodontal disease: modulation of the inflammatory cascade by dietary n-3 polyunsaturated fatty acids.  

Science.gov (United States)

Periodontal disease, including gingivitis and periodontitis, is caused by the interaction between pathogenic bacteria and the host immune system. The ensuing oxidative stress and inflammatory cascade result in the destruction of gingival tissue, alveolar bone and periodontal ligament. This article reviews the underlying mechanisms and host-bacteria interactions responsible for periodontal disease and evidence that nutritional supplementation with fish oil may provide a protective effect. Historical investigations of diet and disease have highlighted an inverse relationship between ingestion of fish oil, which is high in n-3 polyunsaturated fatty acids, and the incidence of typical inflammatory diseases such as arthritis and coronary heart disease. Ingestion of n-3 polyunsaturated fatty acids, such as docosahexaenoic acid and eicosapentaenoic acid, results in their incorporation into membrane phospholipids, which can alter eicosanoid production after stimulation during the immune response. These eicosanoids promote a reduction in chronic inflammation, which has led to the proposal that fish oil is a possible modulator of inflammation and may reduce the severity of periodontal diseases. Tentative animal and human studies have provided an indication of this effect. Further human investigation is needed to establish the protective effects of fish oil in relation to periodontal disease. PMID:23889472

Sculley, D V

2014-06-01

233

Occurrence of periodontal pathogens among patients with chronic periodontitis  

OpenAIRE

The aim of the present study was to evaluate the presence of the periodontal pathogens that form the red complex (Tannerella forsythia, Porphyromonas gingivalis and Treponema denticola) and Aggregatibacter actinomycetemcomitans in patients with chronic periodontitis. The sample consisted of 29 patients with a clinical and radiographic diagnosis of chronic periodontitis based on the criteria of the American Academy of Periodontology (3). Samples for microbiological analysis were collected from...

Farias, B. C.; Souza, P. R. E.; Ferreira, B.; Melo, R. S. A.; Machado, F. B.; Gusma?o, E. S.; Cimo?es, R.

2012-01-01

234

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

235

Periodontal cell implantation contributes to the regeneration of the periodontium in an indirect way.  

Science.gov (United States)

Periodontitis is the most common human infectious disease. Regeneration of bone and soft tissue defects after periodontitis remains challenging, although the transplantation of periodontal ligament (PDL) cells seems a liable strategy. However, little is known about the function of PDL cells after transplantation. In the current study, a combination of in vitro coculture systems and in vivo immunohistochemistry (IHC) was used to investigate the role of PDL cells in the regenerative process. First, a coculture method was used, in which mesenchymal cells (representing the host tissue) were brought into direct contact with PDL cells (representing the transplanted cell population). It was found that PDL cells significantly increased mineralized matrix formation and osteocalcin expression, whereas control cells did not. Similar results were obtained when a noncontact coculture system was applied separating PDL and mesenchymal cells. In an in vivo rat model, regeneration of alveolar bone and ligament was seen after PDL cell transplantation. Implanted PDL cells were found clustered along the newly formed tissues. IHC showed enhanced osteopontin expression and gap junction staining in areas neighboring implanted PDL cells. In conclusion, PDL cells enhance periodontal regeneration through a trophic factor stimulating the osteogenic activity of the surrounding host cells. PMID:25077766

Yu, Na; Bronckers, Antonius L J J; Oortgiesen, Daniel A W; Yan, Xiangzhen; Jansen, John A; Yang, Fang; Walboomers, X Frank

2015-01-01

236

SUBGINGIVAL MICROBIOTA IN SEVERE CHRONIC PERIODONTITIS  

OpenAIRE

Literature data relate certain Gram-negative anaerobe microorganisms with advanced destructive periodontal lesion. There are some references which reported higher levels of periodontal pathogens by the red and orange complex in deep periodontal pockets. The aim of this study is to determine the presence of most important periodontal pathogens and Candida spp. in deep periodontal pockets in patients with severe chronic periodontitis. The results of this study indicate the presence of high leve...

Christina Popova; Velitchka Dosseva-Panova; Angelina Kisselova-Yaneva; Panov, Vladimir E.

2014-01-01

237

The Relationship between Diabetes Mellitus and Periodontitis  

OpenAIRE

Chronic gingivitis and periodontitis are common inflammatory conditions of the periodontal tissues. Given the ‘right’ concurrence of risk factors, a person with periodontitis can experience significant destruction of tooth-supporting bone, ultimately resulting in tooth loss. Poorly controlled diabetes is an important risk factor for periodontitis, and gingivitis and periodontitis are sometimes the first sign that a patient has diabetes. As severe periodontitis can lead to the loss of teet...

Hussain, A. M.

2011-01-01

238

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

239

Gene Polymorphisms in Chronic Periodontitis  

OpenAIRE

We aimed to conduct a review of the literature for gene polymorphisms associated with chronic periodontitis (CP) susceptibility. A comprehensive search of the literature in English was performed using the keywords: periodontitis, periodontal disease, combined with the words genes, mutation, or polymorphism. Candidate gene polymorphism studies with a case-control design and reported genotype frequencies in CP patients were searched and reviewed. There is growing evidence that polymorphisms in ...

Laine, Marja L.; Loos, Bruno G.; Crielaard, W.

2010-01-01

240

Immunohistochemical detection of ENaCbeta in the terminal Schwann cells associated with the periodontal Ruffini endings of the rat incisor.  

Science.gov (United States)

Epithelial sodium channels (ENaCs) are a subfamily of ion channels within the degenerin/ENaC (DEG/ENaC) superfamily. Previous studies have shown the immunolocalization of ENaC in the neural elements of the cutaneous mechanoreceptors as well as dorsal root and trigeminal ganglion neurons, indicating the involvement of this molecule in mechanotransduction. The present study examined the expression of ENaCbeta, a major component of ENaC protein, in the mechanoreceptive Ruffini endings in the periodontal ligament of the rat incisors by immunohistochemistry. The expression of ENaCbeta in the trigeminal ganglion--which innervates the periodontal Ruffini endings--was also investigated at the mRNA and protein levels. Furthermore, double staining and a nerve injury experiment were applied to clarify its detailed localization in the periodontal Ruffini endings. ENaCbeta immunoreaction in the trigeminal ganglion was recognizable in the comparatively large neurons which have been considered to mediate mechanotransduction. Immunohistochemistry for ENaCbeta demonstrated dendritic ramifications of the Ruffini endings as well as the rounded cells in the periodontal ligament. Double staining with ENaCbeta and either PGP9.5 or S-100 protein showed immunoreaction for ENaCbeta in both the axonal and glial elements in the periodontal ligament. Some ENaCbeta positive cells with rounded profiles were reactive to non-specific cholinesterase activity. Furthermore, a transection of the inferior alveolar nerve failed to eliminate the rounded cells with ENaCbeta reaction, indicating that they were the terminal Schwann cells associated with the periodontal Ruffini endings. These findings suggest that ENaCbeta is a key mechanotransducing channel in the periodontal Ruffini endings. Probably, the terminal Schwann cells together with the axon terminals regulate mechanotransduction in the periodontal endings. PMID:19420735

Hitomi, Yasumasa; Suzuki, Akiko; Kawano, Yoshiro; Nozawa-Inoue, Kayoko; Inoue, Makoto; Maeda, Takeyasu

2009-04-01

241

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, Y; Boudreau, S

2010-01-01

242

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

243

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

244

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

245

Risk factors for periodontal disease.  

Science.gov (United States)

Risk factors play an important role in an individual's response to periodontal infection. Identification of these risk factors helps to target patients for prevention and treatment, with modification of risk factors critical to the control of periodontal disease. Shifts in our understanding of periodontal disease prevalence, and advances in scientific methodology and statistical analysis in the last few decades, have allowed identification of several major systemic risk factors for periodontal disease. The first change in our thinking was the understanding that periodontal disease is not universal, but that severe forms are found only in a portion of the adult population who show abnormal susceptibility. Analysis of risk factors and the ability to statistically adjust and stratify populations to eliminate the effects of confounding factors have allowed identification of independent risk factors. These independent but modifiable, risk factors for periodontal disease include lifestyle factors, such as smoking and alcohol consumption. They also include diseases and unhealthy conditions such as diabetes mellitus, obesity, metabolic syndrome, osteoporosis, and low dietary calcium and vitamin D. These risk factors are modifiable and their management is a major component of the contemporary care of many periodontal patients. Genetic factors also play a role in periodontal disease and allow one to target individuals for prevention and early detection. The role of genetic factors in aggressive periodontitis is clear. However, although genetic factors (i.e., specific genes) are strongly suspected to have an association with chronic adult periodontitis, there is as yet no clear evidence for this in the general population. It is important to pursue efforts to identify genetic factors associated with chronic periodontitis because such factors have potential in identifying patients who have a high susceptibility for development of this disease. Many of the systemic risk factors for periodontal disease, such as smoking, diabetes and obesity, and osteoporosis in postmenopausal women, are relatively common and can be expected to affect most patients with periodontal disease seen in clinics and dental practices. Hence, risk factor identification and management has become a key component of care for periodontal patients. PMID:23574464

Genco, Robert J; Borgnakke, Wenche S

2013-06-01

246

Periodontal regeneration following use of ABM/P-1 5: a case report.  

Science.gov (United States)

ABM/P-15 is a combination of a natural anorganic bovine-derived hydroxyapatite matrix (ABM) and a synthetic cell-binding peptide (P- 15; PepGen P- 15) that has shown the capacity to encourage substantial clinical fill of periodontal infrabony defects. Human histology following its use has not been evaluated on pathologic root surfaces. A maxillary lateral incisor with advanced adult periodontitis that was treatment planned for extraction was treated with sulcular incisions, full-thickness flap reflection, debridement of granulomatous tissue from the defect, placement of a notch in the root at the apical extent of calculus, mechanical root planing, brief cleansing with citric acid, grafting with ABM/P-15, wound closure with sutures, and placement of a periodontal dressing. Biweekly to monthly recalls were made until removal of a small block section biopsy at about 6 months. Histologic evaluation of the region coronal to the apical edge of the calculus notch showed evidence of regeneration (new cementum, bone, and periodontal ligament). Graft particles were still present at 6 months, but no evidence of root resorption, ankylosis, or untoward inflammation was seen. This case report fulfills the proof of principle that use of ABM/P-15 can result in periodontal regeneration on previously diseased root surfaces in humans. PMID:12019710

Yukna, Raymonda; Salinas, Thomas J; Carr, Ronald F

2002-04-01

247

Common periodontal diseases of children and adolescents.  

Science.gov (United States)

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 database search using key terms: "periodontal diseases in children," "Periodontal diseasesin adolescents," "periodontal diseases risk factors," "microbiology of periodontal diseases," "classification of periodontal diseases," "epidemiology of periodontal diseases," and "treatment of periodontal diseases." Articles were evaluated by title and/or abstract and relevance to pediatric dentistry. Sixty-five citations were selected by this method and by the references within the chosen articles. A review of the comprehensive textbooks on pediatric dentistry and periodontology was done. Some recommendations were based on the opinions of experienced researchers and clinicians, when data were inconclusive. PMID:25053946

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

2014-01-01

248

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

249

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

250

Collateral ligament (CL) injury - aftercare  

Science.gov (United States)

... you may need surgery if your LCL is injured or if your injuries are severe and involve other ligaments in your knee. ... heal. You should use crutches to protect the injured ligament. ... around your knee stronger and more flexible. You may need to ...

251

In vitro differentiation and attachment of human embryonic stem cells on periodontal tooth root surfaces.  

Science.gov (United States)

Periodontal tissue engineering based on cell replacement therapies is a promising field for improved regeneration of tooth supporting structures lost as a result of destructive periodontal diseases. Human embryonic stem cells (hESCs) could become adequate cell source for tissue engineering because of their unlimited proliferative potential and ability to differentiate to all somatic cell types. The aim of this study was to analyze the differentiation capacity of hESCs toward periodontal compartment cells and their relationship with tooth root surfaces in vitro. Periodontal ligament fibroblastic cell (PDLF) cultures were established and characterized; hESCs (HUES-9 line) were expanded in undifferentiated state and characterized for pluripotency morphologically and immunohistochemically. Extracted tooth root slices (RS) of 300 microm thickness, prepared with both periodontal and endodontic instrumentation, were used. Three different experimental groups were established: (i) undifferentiated hESC colonies cultured on and around the RS; (ii) undifferentiated hESC colonies cultured on and around RS with PDLF coculture, and (iii) undifferentiated hESC colonies cultured on and around RS with PDLF coculture in osteoinductive medium for 3 weeks. The fibrogenic and osteogenic marker expression was assessed with immunohistochemistry; histological staining and scanning electron microscopy were utilized to determine the relationship between differentiating hESCs and mineralized tooth root structures. Results demonstrate that hESC differentiation is influenced by tooth structures, PDLFs, and osteogenic medium, resulting with increased propensity toward mesenchymal lineage commitment, and formation of soft-hard tissue relationship in close contact areas. The proposed experimental system may facilitate further understanding in development of periodontal structures and contribute to realization of hESCs as a cell source in periodontal tissue engineering applications. PMID:19405785

Inanç, Bülend; Elçin, A Eser; Elçin, Y Murat

2009-11-01

252

Contesting conventional periodontal wisdom : implications for periodontal classifications  

DEFF Research Database (Denmark)

This paper examines the common approach used to classify periodontal diseases and how this obstructs our understanding of the disease process. We address the implications of including etiological and pathogenesis-related considerations in the classifications of complex diseases like periodontitis and argue that the number of periodontal entities in a classification system ought to be determined by well-documented differences in the management of each entity. We finally discuss how an ecosocial theory of disease distribution can be helpful to understand the determinants of the distribution of disease in the population.

Lopez, Rodrigo; Baelum, Vibeke

2012-01-01

253

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

254

Severe Periodontitis Is Inversely Associated with Coffee Consumption in the Maintenance Phase of Periodontal Treatment  

OpenAIRE

This cross-sectional study addressed the relationship between coffee consumption and periodontitis in patients during the maintenance phase of periodontal treatment. A total of 414 periodontitis patients in the maintenance phase of periodontal treatment completed a questionnaire including items related to coffee intake and underwent periodontal examination. Logistic regression analysis showed that presence of moderate/severe periodontitis was correlated with presence of hypertension (Odds Rat...

Tatsuya Machida; Takaaki Tomofuji; Daisuke Ekuni; Tetsuji Azuma; Noriko Takeuchi; Takayuki Maruyama; Shinsuke Mizutani; Kota Kataoka; Yuya Kawabata; Manabu Morita

2014-01-01

255

Study of the patterns of periodontal destruction in smokers with chronic periodontitis  

OpenAIRE

Cigarette smoking is a well-established risk factor for periodontitis and carries an increased risk for loss of periodontal attachment as well as for bone loss. Aims: The purpose of the study was to investigate the pattern of the intraoral distribution of periodontal destruction among cigarette smokers with periodontitis by assessing the periodontal probing depth (PPD) and clinical attachment level (CAL). Materials and Methods: Thirty smokers with chronic periodontitis were enrolled in th...

Anil Sukumaran

2008-01-01

256

CT of the pulmonary ligament  

Energy Technology Data Exchange (ETDEWEB)

Most computed tomographic (CT) scans of the chest show the inferior pulmonary ligament and an associated septum in the lower lobe, although CT descriptions of these structures have not been reported. Conventional radiography of the ligament has relied on indirect signs: the position of the lower lobe in the presence of pneumothorax or pleural effusion, soft-tissue peaks along the upper surface of the diaphragm, and the rare traumatic paramediastinal pneumatocele (attributed to air in the ligament). CT clarifies the anatomic relations of the ligament and alterations caused by pleural effusion and pneumothorax. The ligament is probably responsible for some long linear shadows at the lung bases, and CT helps to distinguish these from scars, walls of bullae, and normal structures such as the phrenic nerve and the interlobar fissures.

Godwin, J.D.; Vock, P.; Osborne, D.R.

1983-08-01

257

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

258

Centipeda periodontii in human periodontitis.  

Science.gov (United States)

This study assessed the subgingival occurrence of the flagellated, Gram-negative, anaerobic rod Centipeda periodontii in chronic periodontitis and periodontal health/gingivitis with species-specific nucleic acid probes, and evaluated the in vitro resistance of subgingival isolates to therapeutic levels of amoxicillin, metronidazole, and doxycycline. Subgingival plaque biofilm specimens from 307 adults with chronic periodontitis, and 48 adults with periodontal health/localized gingivitis, were evaluated with digoxigenin-labeled, whole-chromosomal, DNA probes to C. periodontii ATCC 35019 possessing a 10(4) cell detection threshold. Fifty-two C. periodontii subgingival culture isolates were assessed on antibiotic-supplemented enriched Brucella blood agar for in vitro resistance to either amoxicillin at 2 µg/ml, metronidazole at 4 µg/ml, or doxycycline at 2 µg/ml. A significantly greater subgingival occurrence of C. periodontii was found in chronic periodontitis subjects as compared to individuals with periodontal health/gingivitis (13.4 vs. 0 %, P human periodontitis. PMID:25037463

Rams, Thomas E; Hawley, Charles E; Whitaker, Eugene J; Degener, John E; van Winkelhoff, Arie J

2014-07-19

259

[Traumatology of the alar ligaments].  

Science.gov (United States)

A postmortem study of craniocerebral traumas of varying severity was done to determine the pattern of injury of the alar ligaments. It was found that in the entire group of patients (n = 30) the alar ligaments were ruptured or suffused with blood 11 times. No close relationship was found between the massive nature of the cranial trauma and the severity of the injury of the alar ligaments. In some cases the alar ligaments were not at all involved even though the skull had suffered extensive osseous lesions, whereas on the other hand the ligaments were injured even though only soft parts had been involved (e.g., haematoma or dehiscent wounds of the scalp). Ruptures of the alar ligaments were typically involved in extended ruptures of the ligamentous apparatus (see Figure 6a involving the ligamentum apicis dentis, ligamentum transversum atlantis, m.atlanto-occipitalis anterior, m.tectoria, m.atlanto-axialis anterior et posterior). In some cases the pattern of injury of the alar ligaments was found to be decisive in enabling reconstruction of the course of the accident. Damage to the alar ligaments near the dens axis represent rotation injuries. On the other hand, insertion tears out of the condyli occipitales must be related to a lateral thrust tendency in indirect fracture of the skull (bursting fracture). Within this overall framework a new mechanism of fracture of the condylus occipitalis is described. As a matter of principle, the alar ligaments can become involved in consequence of rotation, traction and compression of the cranium. PMID:2891250

Saternus, K S; Thrun, C

1987-10-01

260

Possibilities of endodontic therapy of endodonic-periodontal lesions  

Directory of Open Access Journals (Sweden)

Full Text Available Intoduction. Endoperiodontal lesions are frequent in clinical practice and may require complex therapy. It is very important to determine differential diagnosis and the origin of the lesion, because the treatment plan is based on aetiology and stadium of the development of the lesion. Objective. The aim of this clinical study was to analyze the efficacy of endodontic treatment in different types of endodontic- periodontal lesions. Methods. Thirty patients and 42 teeth with diagnosed endoperiodontal lesions were included in the study and divided in two groups. Vital pulp therapy was applied to 18 vital teeth where the diagnosis was perio-endodontic lesions. The therapy of infected canal system was applied to 24 teeth with endodontic- periodontal or combined lesions. Standard endodontic procedure consisted of cleaning and shaping of the root canal system and between sessions filling with calcium-hydroxide paste. Obturation was made by lateral compact of the guttapercha and Apexit paste. Efficiency was evaluated clinically and radiographically three, six and twelve months later. Results. Radiographic and clinical follow-up showed a significant radiographic improvement and absence of subjective symptoms in a very high percentage of the treated vital and avital teeth. The results of this study showed that in the observation period of 12 months endodontic therapy was successful in 88.89% of vital teeth, and in the group of avital teeth the percentage was 91.67%. Conclusion. Endodontic treatment of the endoperiodontal lesions was sufficient and it was the basic condition to achieve a complete healing of endodontic-periodontal lesions. Such therapy ensures significant improvement or even complete healing of both types of lesions, of endodontic and periodontal origin.

Neškovi? Jelena

2009-01-01

261

Relationship between clinical periodontal condition and the radiological appearance at 1st molar sites in adolescents. A 3-year study.  

Science.gov (United States)

There has been considerable controversy about the incidence of periodontal disease in adolescents. It is noteworthy that there is disagreement between workers as to be radiological features that should be used to detect the earliest signs of periodontitis, and variation in the choice of criteria may have influenced the results of previous studies. The present project represents a 3-year longitudinal assessment into the periodontal condition, assessed clinically and radiologically, of a group of adolescents. The radiographic investigations were carried out using vertical bitewing radiographs and, to reduce potential error caused by variation in film placement and tube alignment, individual impressions were used so that the film could be positioned accurately at repeat assessments. It was found that several of the radiographic features, such as the width of the periodontal ligament space and the angle of the interproximal bone crest relative to the tooth, similar to those previously attributed to the commencement of destructive periodontal changes, were found to be correlated with the maturation changes associated with the eruption of the adjoining permanent teeth. In spite of the use of impressions, some of the series of radiographs showed variation in tube alignment, and several of the above radiological features were also found to correlate with errors in radiographic technique. It was concluded that the various eruptive and maturation changes taking place during this stage in the adolescent dentition must be allowed for when looking for the earliest signs of periodontal destruction. PMID:8157766

Waite, I M; Furniss, J S; Wong, W M

1994-03-01

262

Functional tissue engineering of ligament healing  

OpenAIRE

Abstract Ligaments and tendons are dense connective tissues that are important in transmitting forces and facilitate joint articulation in the musculoskeletal system. Their injury frequency is high especially for those that are functional important, like the anterior cruciate ligament (ACL) and medial collateral ligament (MCL) of the knee as well as the glenohumeral ligaments and the rotator cuff tendons of the shoulder. Because the healing responses are different in these ligaments and tendo...

Hsu Shan-Ling; Liang Rui; Ly, Woo Savio

2010-01-01

263

Lateral condensation in treatment of pulpitis and pulp gangrene: studies on dog canine teeth.  

Science.gov (United States)

The clinical investigation, carried out in dogs, comprises selected cases of chronic pulpitis and pulpal gangrene of canine teeth resulting from injuries. A group of 20 teeth (group 1) underwent extirpation of pulp, as well as elaboration of a root canal and its filling with Endomethasone paste, under general anaesthesia during a one-stage procedure. The second group of 20 teeth differed from the first in an additional concentration of the paste, due to an introduction of gutta-percha points (lateral condensation). This sealing modification proved to diminish the risk of leaving empty spaces after pulp removal in the pulpitis state. However, in teeth where gangrenous pulp extirpation was performed, lateral condensation was endangered by pushing the paste through beyond the apex. Both anomalies were likely to predispose to the development of apical periodontitis. PMID:9673569

Ratajczak, K; Gawor, J

1998-04-01

264

Low-cost periodontal therapy.  

Science.gov (United States)

Periodontitis is a complex infectious disease that affects low-income individuals disproportionately. Periodontitis is associated with specific bacterial species and herpesviruses, and successful prevention and treatment of the disease is contingent upon effective control of these pathogens. This article presents an efficacious, highly safe, minimally invasive, practical and low-cost periodontal therapy that involves professional and patient-administered mechanical therapy and antimicrobial agents. The major components are scaling for calculus removal, periodontal pocket irrigation with potent antiseptics, and treatment with systemic antibiotics for advanced disease. Povidone-iodine and sodium hypochlorite have all the characteristics for becoming the first-choice antiseptics in the management of periodontal diseases. Both agents show excellent antibacterial and antiviral properties, are readily available throughout the world, have been safely used in periodontal therapy for decades, offer significant benefits for individuals with very limited financial resources, and are well accepted by most dental professionals and patients. Four per cent chlorhexidine applied with a toothbrush to the most posterior part to the tongue dorsum can markedly reduce or eliminate halitosis in most individuals. Systemic antibiotics are used to treat periodontopathic bacteria that are not readily reached by topical therapy, such as pathogens within gingival tissue, within furcation defects, at the base of periodontal pockets, and on the tongue, tonsils and buccal mucosae. Valuable antibiotic therapies are amoxicillin-metronidazole (250?mg of amoxicillin and 250?mg of metronidazole, three times daily for 8?days) for young and middle-aged patients, and ciprofloxacin-metronidazole (500?mg of each, twice daily for 8?days) for elderly patients and for patients in developing countries who frequently harbor enteric rods subgingivally. Scaling to remove dental calculus and the prudent use of inexpensive antimicrobial agents can significantly retard or arrest progressive periodontitis in the great majority of patients. PMID:22909110

Slots, Jørgen

2012-10-01

265

The Relationship between Diabetes Mellitus and Periodontitis  

Directory of Open Access Journals (Sweden)

Full Text Available Chronic gingivitis and periodontitis are common inflammatory conditions of the periodontal tissues. Given the ‘right’ concurrence of risk factors, a person with periodontitis can experience significant destruction of tooth-supporting bone, ultimately resulting in tooth loss. Poorly controlled diabetes is an important risk factor for periodontitis, and gingivitis and periodontitis are sometimes the first sign that a patient has diabetes. As severe periodontitis can lead to the loss of teeth, it is important that patients with diabetes practise good oral hygiene and have regular dental check-ups so that problems can be detected quickly

A.M.Hussain

2011-01-01

266

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.

267

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

268

Periodontal and hematological characteristics associated with aggressive periodontitis, juvenile idiopathic arthritis, and rheumatoid arthritis  

DEFF Research Database (Denmark)

Periodontitis shares several clinical and pathogenic characteristics with chronic arthritis, and there is some degree of coexistence. The aims of this study were to elucidate whether patients with localized aggressive periodontitis (LAgP), generalized aggressive periodontitis (GAgP), juvenile idiopathic arthritis (JIA), and rheumatoid arthritis (RA) share periodontal and hematological characteristics distinguishing them from individuals free of diseases.

Poulsen, Anne Havemose; Westergaard, Jytte

2006-01-01

269

Supportive periodontal therapy and periodontal biotype as prognostic factors in implants placed in patients with a history of periodontitis  

OpenAIRE

Objectives: To evaluate bone loss around implants placed in patients with a history of treated chronic periodontitis and who did or did not attend supportive periodontal therapy, after one year in function. Furthermore, the influence of periodontal biotype and level of plaque was also evaluated. Material and Methods: Forty-nine patients participated voluntarily in the study. All subjects had a history of chronic periodontitis, which had been previously treated. After the active treatment, ...

Aguirre-zorzano, Luis A.; Vallejo-aisa, Francisco J.; Estefani?a-fresco, Ruth

2013-01-01

270

The immunopathogenesis of periodontal disease.  

Science.gov (United States)

Treatment planning in periodontics, as with any disease, must be based on an understanding of the aetiology and pathogenesis of the disease. In this context, it has slowly become recognized over the past three decades that while plaque is the cause of the disease, it is the innate susceptibility of the host that determines the ultimate outcome of the disease process. Innate susceptibility, in turn, is determined by the nature of the immune response to the specific periodontopathic complexes comprising the plaque biofilm. The aim of this review was to examine current understanding of the immunopathogenesis of chronic periodontitis with respect to its possible clinical implications in terms of treatment planning and risk assessment. Numerous studies have demonstrated that the periodontitis lesion itself involves predominantly B cells and plasma cells, while the gingivitis lesion is primarily a T cell mediated response. This led to the concept over 30 years ago that the development of periodontitis involves a switch from a T cell lesion to one involving large numbers of B cells and plasma cells. It is also well recognized that control of this shift is mediated by a balance between the so-called Th1 and Th2 subsets of T cells, with chronic periodontitis being mediated by Th2 cells. More recently, T regulatory (Treg) and Th17 cells have been demonstrated in periodontal tissues, raising the possibility that these cells are also important in the immunoregulation of periodontal disease. The clinical implications of these observations can be seen in the fact that identification of Th1/Th2 and Treg/Th17 cytokine gene expression in the peripheral blood and salivary transcriptomes is now being trialled as a possible marker of disease susceptibility. If this proves to be the case, a chairside salivary diagnostic could be developed within the next five to 10 years. PMID:19737265

Ohlrich, E J; Cullinan, M P; Seymour, G J

2009-09-01

271

Information generation and processing systems that regulate periodontal structure and function.  

Science.gov (United States)

The periodontium is a very dynamic organ that responds rapidly to mechanical and chemical stimuli. It is very complex in that it is composed of two hard tissues (cementum and bone) and two soft connective tissues (periodontal ligament and gingiva). Together these tissues are defined by the molecules expressed by the resident periodontal cells in each compartment and this determines not only the structure and function of the periodontium but also how it responds to infection and inflammation. The biological activity of these molecules is tightly regulated in time and space to preserve tissue homeostasis, influence inflammatory responses and participate in tissue regeneration. In this issue of Periodontology 2000 we explore new experimental approaches and data sets which help to understand the molecules and cells that regulate tissue form and structure in health, disease and regeneration. PMID:23931050

Bartold, P Mark; McCulloch, Christopher A

2013-10-01

272

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

273

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

274

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

275

Oxidative Stress, Systemic Inflammation, and Severe Periodontitis  

OpenAIRE

Periodontal infections have been associated with a state of chronic inflammation. To ascertain whether severe periodontitis and its treatment are associated with oxidative stress, we recruited 145 cases (periodontitis) and 56 controls in a case-control study. A further pilot intervention study of 14 cases (periodontal therapy) was performed. Blood samples were taken at baseline (case-control) and 1, 3, 5, 7, and 30 days after treatment (intervention). Diacron-reactive oxygen metabolites (D-RO...

D’aiuto, F.; Nibali, L.; Parkar, M.; Patel, K.; Suvan, J.; Donos, N.

2010-01-01

276

Treatment of periodontitis and endothelial function  

OpenAIRE

Background: Systemic inflammation may impair vascular function, and epidemiologic data suggest a possible link between periodontitis and cardiovascular disease. Methods: We randomly assigned 120 patients with severe periodontitis to community-based periodontal care (59 patients) or intensive periodontal treatment (61). Endothelial function, as assessed by measurement of the diameter of the brachial artery during flow (flow-mediated dilatation), and inflammatory biomarkers and markers of c...

Tonetti, M. S.; D Aiuto, F.; Nibali, L.; Donald, A.; Storry, C.; Parkar, M.; Suvan, J.; Hingorani, A. D.; Vallance, P.; Deanfield, J.

2007-01-01

277

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

278

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

279

Poor periodontal health: A cancer risk?  

OpenAIRE

Evidence indicates that chronic infections and inflammation are associated with increased risk of cancer development. There has also been considerable evidence that proves the interrelationship between bacterial and viral infections and carcinogenesis. Periodontitis is a chronic oral infection thought to be caused by gram-negative anaerobic bacteria in the dental biofilm. Periodontal bacteria and viruses may act synergistically to cause periodontitis. Many studies have shown that periodontal ...

Rajesh, K. S.; Thomas, Deepak; Hegde, Shashikanth; Kumar, M. S. Arun

2013-01-01

280

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

281

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

282

Genetic polymorphisms in periodontal diseases: An overview  

OpenAIRE

Periodontitis is a multi-factorial disease; several risk and susceptibility factors are proposed in its natural history. Genetics is considered a susceptibility factor in relation to periodontitis. This article is a nonsystematic review of literature and focuses on the role of genetic polymorphisms in periodontal diseases.

Vijayalakshmi R; Geetha A; Ramakrishnan T; Emmadi Pamela

2010-01-01

283

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

284

Immunohistochemical expression of heat shock proteins in the mouse periodontal tissues due to orthodontic mechanical stress  

OpenAIRE

Abstract The histopathology of periodontal ligament of the mouse subjected to mechanical stress was studied. Immunohistochemical expressions of HSP27 and pHSP27 were examined. Experimental animals using the maxillary molars of ddY mouse by Waldo method were used in the study. A separator was inserted to induce mechanical stress. After 10 minutes, 20 minutes, 1 hour, 3 hours, 9 hours and 24 hours, the regional tissues were extracted, fixed in 4% paraformaldehyde and 0.05 M phosphate-buffered f...

Muraoka R; Nakano K; Kurihara S; Yamada K; Kawakami T

2010-01-01

285

Occurrence of periodontal pathogens among patients with chronic periodontitis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The aim of the present study was to evaluate the presence of the periodontal pathogens that form the red complex (Tannerella forsythia, Porphyromonas gingivalis and Treponema denticola) and Aggregatibacter actinomycetemcomitans in patients with chronic periodontitis. The sample consisted of 29 patie [...] nts with a clinical and radiographic diagnosis of chronic periodontitis based on the criteria of the American Academy of Periodontology (3). Samples for microbiological analysis were collected from the four sites of greatest probing depth in each patient, totaling 116 samples. These samples were processed using conventional polymerase chain reaction, which achieved the following positive results: 46.6% for P. gingivalis, 41.4% for T. forsythia, 33.6% for T. denticola and 27.6% for A. actinomycetemcomitans. P. gingivalis and T. forsythia were more prevalent (p

B.C., Farias; P.R.E., Souza; B., Ferreira; R.S.A., Melo; F.B., Machado; E.S., Gusmão; R., Cimões.

2012-09-01

286

Enfermedad periodontal y climaterio / Periodontal disease and climaterium  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Se realizó un estudio descriptivo y transversal de 282 pacientes que se encontraban en la etapa del climaterio, que acudieron a la consulta de Endocrinología del Policlínico de Especialidades del Hospital Provincial Docente Clinicoquirúrgico "Saturnino Lora Torres" de Santiago de Cuba, durante el 20 [...] 12, con vistas a caracterizar el estado de la enfermedad periodontal en este grupo según variables de interés clínico, periodontal y epidemiológico. Se obtuvo que la severidad de la enfermedad gingival y periodontal estuvo directamente relacionada con los grados de higiene bucal regular y malo, con predominio de la gingivitis (90,4 %), de la gingivitis severa (81,7 %), así como de la periodontitis establecida con higiene bucal regular (79,1 %) y de la periodontitis terminal con higiene bucal mala (76,0%); asimismo, la gingivitis resultó ser la afección más común en ambas etapas del período climatérico (67,9 y 35,3 % en las premenopáusicas y posmenopáusicas, respectivamente). Se demostró que a medida que pasan los años sin efecto estrogénico, la riesgo de la afección se incrementa, sin existir relación entre esta y la edad en que ocurrió la menopausia o la gravedad del síndrome climatérico. Se recomienda continuar las investigaciones para conocer el estado de la enfermedad periodontal en pacientes climatéricas a escala nacional y elaborar programas destinados a la prevención. Abstract in english A descriptive and cross-sectional study of 282 patients who were in the climacteric stage and were assisted in the Endocrinology Department of the Specialties Polyclinic from "Saturnino Lora Torres" Clinical Surgical Teaching Provincial Hospital in Santiago de Cuba was carried out during the 2012, w [...] ith the aim of characterizing the periodontal disease in this group according to variables of clinical, periodontal and epidemiological interest. It was obtained that the severity of the gingival and periodontal disease was directly related to the degrees of mean and poor oral hygiene, with prevalence of the gingivitis (90.4%), of the severe gingivitis (81.7%), as well as of the established periodontitis with mean oral hygiene (79.1%) and of the terminal periodontitis with poor oral hygiene (76.0%); also, gingivitis turned out to be the most common disorder in both stages of the climacteric period (67.9 and 35.3% in the premenopausic and posmenopausic women, respectively). It was demonstrated that, as the years pass without estrogenic effect, the risk for the disease increases, without existing relationship between it and the age in which menopause or the severity of the climacteric syndrome took place. It is recommended to continue the investigations to know the periodontal disease in climacteric patients at a national scale and to implement programs aimed at its prevention.

María Isabel, Aguilar Vallejo; Maritza, Peña Sisto; Jacqueline, Chacón Rodríguez; Frederick, Fernández Villasante; Dixan, Gutierrez Torres.

2014-02-01

287

Influence of dimethyl formamide pulping of bagasse on pulp properties.  

Science.gov (United States)

Organosolv pulping of bagasse was conducted following a central composite design using a two-level factorial plan involving three pulping variables (temperature: 190-210 degrees C, time: 120-180 min, organic solvent charge: 40-60% dimethyl formamide). Responses of pulp properties (yield and holocellulose, alpha-cellulose, kappa number, ash and ethanol-dichloromethane extractives contents) and the pH of the resulting wastewater to the process variables were analyzed using statistical software (MINITAB). Main factor analysis revealed that optimum pulp has the following characteristics: 82.7% (yield), 92.9 (kappa number), 95.84% (holocellulose), 83.53% (alpha-cellulose), 1.403% (ash), 2.562% (ethanol-dichloromethane extractives contents) and 6.39 (pH). These results showed that acceptable properties of pulps could be gained at 200-210 degrees C for 150 min and 40-60% DMF. Based on these results, this method could be used for pulping of bagasse equivalent NSSC concerning high yield at a fixed kappa number. In addition, bagasse could be pulped with ease to approximately 55% yield with a kappa number approximately 31. Numerical analyses showed that cooking temperature had the greatest influence on properties of obtained pulps within the DMF concentrations and cooking time as cooking variables. PMID:16324845

Rezayati-Charani, P; Mohammadi-Rovshandeh, J; Hashemi, S J; Kazemi-Najafi, S

2006-12-01

288

Periodontal plastic surgery.  

Science.gov (United States)

The aim of the present article is to summarize current knowledge in terms of the etiology, diagnosis, prognosis and surgical treatment of gingival recession. Whilst the main etiological factors (i.e. toothbrushing trauma and bacterial plaque) are well established, challenges still remain to be solved in the diagnostic, prognostic and classification processes of gingival recession, especially when the main reference parameter - the cemento-enamel junction - is no longer detectable on the affected tooth or when there is a slight loss of periodontal interdental attachment. Root coverage in single type gingival recession defects is a very predictable outcome following the use of various surgical techniques. The coronally advanced flap, with or without connective tissue grafting, is the technique of choice. The adjunctive use of connective tissue grafts improves the probability of achieving complete root coverage. Surgical coverage of multiple gingival recessions is also predictable with the coronally advanced flap and the coronally advanced flap plus the connective tissue graft, but no data are available indicating which, and how many, gingival recessions should be treated adjunctively with connective tissue grafting in order to limit patient morbidity and improve the esthetic outcome. None of the allograft materials currently available can be considered as a full substitute for the connective tissue graft, even if some recent results are encouraging. The need for future studies with patient-based outcomes (i.e. esthetics and morbidity) as primary objectives is emphasized in this review. PMID:25867992

Zucchelli, Giovanni; Mounssif, Ilham

2015-06-01

289

Endometrioma contained within the broad ligament.  

Science.gov (United States)

We present a rare case of an endometrioma present within and firmly adherent to the broad ligament in a patient who experienced an episode of acute abdominal pain. The endometrioma was excised laparoscopically and the broad ligament repaired. PMID:24849806

Trehan, Abhishek; Trehan, Abhishek K; Trehan, Ashwini K; Trehan, Ashwini

2014-01-01

290

Macrophage-mediated nanoparticle delivery to the periodontal lesions in established murine model via Pg-LPS induction  

DEFF Research Database (Denmark)

We established a murine periodontitis model by local injection of lipopolysaccharide of Porphyromonas gingivalis (Pg-LPS) into the gingival sulcus of mandibular left incisor four times with 48-h interval. The histological examination of the periodontal tissues demonstrated that significant loss of periodontal bone and ligaments was observed in the lesion side with abundant inflammatory cell infiltration. Two days after the last injection, Cy5-labelled siRNA/chitosan particles were injected intraperitoneally (ip). The chitosan/siRNA particles were taken up by peritoneal macrophages, which subsequently migrated to the inflamed gingival area evaluated by in vivo imaging. The localization of macrophages in the inflamed region was further confirmed by immunofluorescent staining. The present report demonstrates that intragingival injection of Pg-LPS can be used to create an experimental model of periodontal inflammation in mice and that recruitment of macrophages with chitosan/siRNA nanoparticles to the inflamed area opens the possibility of an RNAi-based therapeutic approach using chitosan as a carrier in periodontitis.

Ma, Zhiwei; Dagnaes-Hansen, Frederik

2014-01-01

291

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.

292

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

293

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

294

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

295

Antibiotic gels for periodontal disease.  

Science.gov (United States)

Periodontal disease is a major cause of tooth loss. The underlying pathology is inflammation caused by bacterial plaque affecting the supporting structures of the teeth. Conventional treatment involves mechanical debridement of calcified plaque (calculus) by the dentist combined with meticulous oral hygiene by the patient. A more recent approach is to apply antimicrobial drugs locally to the diseased gingival tissue after debridement. Two antibiotic preparations, minocycline 2% gel (Dentomycin-Lederle) and metronidazole 25% gel (Elyzol-Dumex), are now licensed for the treatment of patients with periodontal disease. Are these treatments an advance on conventional therapy? PMID:7635031

1994-06-16

296

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, Axel Bjarke Korsgaard

2012-01-01

297

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

298

Critical issues in clinical periodontal research.  

Science.gov (United States)

As periodontal researchers and clinicians, we are challenged every day to make decisions relating to the clinical management of our patients and about how best to conduct clinical periodontal research. This volume of Periodontology 2000 addresses some of the critical issues in contemporary clinical periodontics and periodontal research that are of direct relevance to clinicians, researchers, teachers and students. The 11 review articles in this volume of Periodontology 2000 focus on aspects of periodontal research methodology and clinical periodontology. In terms of research methodology, the articles aim to inform the reader on topics relating to randomized controlled trials in periodontal research, evidence-based dentistry, calibration of clinical examiners and statistics relevant to periodontal research. The clinical periodontology articles address issues relating to decisions on retaining periodontally compromised teeth or replacing them with implants, periodontal management in the patient with osteoporosis, surgical approaches for root coverage and the emerging science of advanced regenerative technologies, including the use of stem cells, for periodontal regeneration. It is hoped that these critical reviews will address many of the dilemmas that confront us on a regular basis and provide practical guidance to those engaged in both clinical periodontology and clinical periodontal research. PMID:22507056

Preshaw, Philip M

2012-06-01

299

Pro-inflammatory cytokine levels in human apical periodontitis: Correlation with clinical and histological findings.  

Science.gov (United States)

This study aimed to compare the levels of tumour necrosis factor-alpha (TNF-?), interleukin-1 beta (IL-1?) and interleukin-6 (IL-6) between apical periodontitis lesions with different clinical and histological features. Based on clinical data and history of disease, 100 human apical periodontitis lesions were categorised as either asymptomatic or symptomatic lesions. According to histological examination, lesions were divided into periapical granulomas and radicular cysts. Pulp tissues of 25 impacted wisdom teeth were used as controls. Homogenised tissue samples were centrifuged and supernatants were used for the determination of cytokine levels by enzyme-linked immunosorbent assay. Significantly higher levels of IL-1? and IL-6 were found in symptomatic lesions compared with asymptomatic lesions and control tissues (P?IL-6, represent an immunologically active stage of the disease. PMID:25163634

Jakovljevic, Aleksandar; Knezevic, Aleksandra; Karalic, Danijela; Soldatovic, Ivan; Popovic, Branka; Milasin, Jelena; Andric, Miroslav

2014-08-27

300

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

301

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

302

Oral Chlamydia trachomatis in Patients with Established Periodontitis  

OpenAIRE

Periodontitis is considered a consequence of a pathogenic microbial infection at the periodontal site and host susceptibility factors. Periodontal research supports the association of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, and Bacteroides forsythus, and periodontitis; however causality has not been demonstrated. In pursuit of the etiology of periodontitis, we hypothesized that the intracellular bacteria, Chlamydia trachomatis, may play a role. A...

Reed, Susan G.; Lopatin, Dennis E.; Foxman, Betsy; Burt, Brian A.

2000-01-01

303

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

304

Periodontal Disease: Causes and Prevention  

Science.gov (United States)

... to help reduce the pressure of clenching or grinding on the teeth. This device is sometimes called an occlusal guard, night guard, mouth guard or bite guard. Stress — Stress can make periodontal disease worse and harder to treat. Stress weakens your body's immune system. This makes it harder for your ...

305

Biomaterials in periodontal osseous defects  

Science.gov (United States)

Introduction Osseous defects in periodontal diseases require osseous grafts and guided tissue regeneration (GTR) using barrier membranes. The present study was undertaken with the objectives to clinically evaluate the osteogenic potential of hydroxyapatite (HA), cissus quadrangularis (CQ), and oxidized cellulose membrane (OCM) and compare with normal bone healing. Materials and Methods Twenty subjects with periodontitis in the age group ranging from 20 years to 40 years were selected from our outpatient department on the basis of presence of deep periodontal pockets, clinical probing depth ?5 mm, vertical osseous defects obvious on radiograph and two- or three-walled involvement seen on surgical exposure. Infrabony defects were randomly divided into four groups on the basis of treatment to be executed, such that each group comprised 5 defects. Group I was control, II received HA, III received CQ and IV received OCM. Probing depth and attachment level were measured at regular months after surgery. Defects were re-exposed using crevicular incisions at 6 months. Results There was gradual reduction in the mean probing pocket depth in all groups, but highly significant in the site treated with HA. Gain in attachment level was higher in sites treated with HA, 3.2 mm at 6 months. Conclusion Hydroxyapatite and OCM showed good reduction in pocket depth, attachment level gain and osseous defect fill. Further study should be conducted by using a combination of HA and OCM in periodontal osseous defects with growth factors and stem cells.

Lal, Nand; Dixit, Jaya

2012-01-01

306

Periodontal Status of Postmenopausal Women  

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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

307

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

308

Periodontal disease epidemiology - learned and unlearned?  

DEFF Research Database (Denmark)

The notion of periodontal disease being the major cause of tooth loss among adults was rooted in the focal infection paradigm that dominated the first half of the 20th century. This paradigm was established largely by personal opinions, and it was not until the development of periodontal indices in the mid-1950s that periodontal epidemiology gained momentum. Unfortunately, the indices used suffered from a number of flaws, whereby the interpretation of the research results took the form of circular reasoning. It was under this paradigm that therapeutic and preventive intervention for periodontal diseases became entirely devoted to oral hygiene, as poor oral hygiene and older age were understood to explain nearly all the variation in disease occurrence. In the early 1980s, studies appeared that contradicted the concepts of poor oral hygiene as the inevitable trigger of periodontitis and of linear and ubiquitous periodontitis progression, whereby periodontal epidemiology was led into a relatively short-lived high-risk era. At this time, it became evident that old scourges continue to haunt periodontology: the inability to agree in operational clinical criteria for a periodontitis diagnosis and the inability to devise both a meaningful and a useful classification of periodontal diseases based on nominalist principles. The meager outcome of the high-risk era led researchers to resurrect the focal infection paradigm, which is now dressed up as periodontal medicine. Unfortunately, these developments have left the core of periodontology somewhat disheveled and deserted.

Bælum, Vibeke; López, Rodrigo

2013-01-01

309

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...

310

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

311

NEWSPRINT FROM SODA BAGASSE PULP IN ADMIXTURE WITH HARDWOOD CMP PULP  

OpenAIRE

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 st...

Seed Rahman Jafari Petroudy; Hossein Resalati Mail; pejman Rezayati Charani Mail

2011-01-01

312

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

313

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

314

Association between Postmenopausal Osteoporosis and Experimental Periodontitis  

OpenAIRE

To investigate the correlation between postmenopausal osteoporosis (PMO) and the pathogenesis of periodontitis, ovariectomized rats were generated and the experimental periodontitis was induced using a silk ligature. The inflammatory factors and bone metabolic markers were measured in the serum and periodontal tissues of ovariectomized rats using an automatic chemistry analyzer, enzyme-linked immunosorbent assays, and immunohistochemistry. The bone mineral density of whole body, pelvis, and s...

Kai Luo; Souzhi Ma; Jianbin Guo; Yongling Huang; Fuhua Yan; Yin Xiao

2014-01-01

315

Identification of periodontal pathogens in atherosclerotic vessels  

DEFF Research Database (Denmark)

Epidemiological studies have shown that periodontitis may be associated with presence of atherosclerosis. DNA from periodontal pathogens has been detected in atherosclerotic lesions, but viable oral bacteria have not yet been isolated from atherosclerotic plaques. The purpose of the present study was to determine if viable oral bacteria could be isolated from atherosclerotic lesions and if DNA from periodontal pathogens could be detected by use of polymerase chain reaction (PCR) techniques.

Fiehn, Nils-Erik; Larsen, Tove

2005-01-01

316

Nonsurgical periodontal treatment: review of the evidence.  

Science.gov (United States)

An increasing number of patients have become aware of the detrimental effects of periodontal disease and tooth-loss and they seek periodontal care. The cornerstone of management of chronic periodontitis is the non-surgical periodontal treatment. The primary goal of periodontal therapy is to preserve the natural dentition by achieving and maintaining a healthy functional periodontium. Many adjunctive treatment modalities have been introduced lately to enhance the therapeutic outcome of periodontal treatment. The aim of this review is to search for systematic reviews which evaluate these therapeutic modalities and discuss their efficacy. The databases of Medline via Ovid, Embase and the Cochrane Database of Systematic Reviews were searched for up to date systematic reviews in English language. The results and conclusions of the systematic reviews found in the periodontal literature are discussed in this paper. The efficacy of different oral hygiene regimens in maintaining and improving gingival health, the efficacy of the nonsurgical periodontal treatment, the full mouth disinfection, the systematic antimicrobial therapy, the local adjunctive therapies, the host modulation treatment, the Photodynamic and laser therapy are discussed. It appears that there is no certain magnitude of initial probing pocket depth where nonsurgical periodontal therapy is no longer effective. Some of the aforementioned modalities have been found to offer statistical significant benefit in clinical outcomes than the scaling and root planing alone. If this statistical significance is clinically significant needs to be critically assessed by the clinician upon the treatment planning and decision making. PMID:24603920

Plessas, Anastasios

2014-03-01

317

Can periodontal infection induce genotoxic effects?  

Science.gov (United States)

Abstract Objective. This study aimed to evaluate the occurrence of chromosomal abnormalities, through micronuclei, and apoptosis by the sum of karyorrhexis, pyknosis and condensed chromatin in individuals with chronic periodontitis, gingivitis associated with biofilm and no periodontal disease. Materials and methods. This study included 72 individuals divided into three groups: gingivitis (n = 21), periodontitis (n = 24) and control (n = 27). Information on sociodemographic characteristics, health and lifestyle was obtained. Full mouth clinical examination was performed to define the periodontal condition. Exfoliated cells from gingival mucosa were collected for computation of micronuclei and nuclear changes indicative of apoptosis. The differences in the occurrence of endpoints (micronucleus, karyorrhexis, pyknosis and condensed chromatin) were evaluated using the conditional test to compare proportions in a rare events situation. Results. There was no statistically significant difference in the occurrence of micronucleus (p > 0.1) between gingivitis, periodontitis and control groups. The occurrence of apoptosis was significantly higher among individuals with periodontitis compared to individuals with gingivitis (p periodontitis is not related to a higher occurrence of chromosomal damage. However, the higher occurrence of apoptosis in individuals with periodontitis points to genotoxic effects induced by periodontal infection. PMID:25428625

Brandão, Paulo de Tarso Jambeiro; Gomes-Filho, Isaac Suzart; Cruz, Simone Seixas; Passos-Soares, Johelle de Santana; Trindade, Soraya Castro; Souza, Leonardo da Cunha Menezes; Meireles, José Roberto Cardoso; Cerqueira, Eneida de Moraes Marcílio

2015-04-01

318

ASSOCIATION OF SERUM ALBUMIN CONCENTRATION AND PERIODONTITIS  

Directory of Open Access Journals (Sweden)

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

319

Automated Periodontal Diseases Classification System  

Directory of Open Access Journals (Sweden)

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

320

Neural network analysis of the information content in population responses from human periodontal receptors  

Science.gov (United States)

Understanding of the information processing in some sensory systems is hampered for several reasons. First, some of these systems may depend on several receptor types with different characteristics, and the crucial features of natural stimuli encoded by the receptors are rarely known with certainty. Second, the functional output of sensory processing is often not well defined. The human tooth is endowed with several types of sensory receptors. Among these, the mechanoreceptors located in the periodontal ligaments have been implicated in force encoding during chewing and biting. Individual receptors cannot, however, code unambiguously either the direction or the magnitude of the applied forces. Neuronal responses recorded in single human nerve fibers from periodontal receptors were fed to multi-layered feed-forward networks. The networks were trained with error back-propagation to identify specific features of the force stimuli that evoked the receptor responses. It was demonstrated that population responses in periodontal receptors contain information about both the point of attack and the direction of applied forces. It is concluded that networks may provide a powerful tool to investigate the information content in responses from biological receptor populations. As such, specific hypotheses with respect to information processing may be tested using neural networks also in sensory systems less well understood than, for instance, the visual system.

Edin, Benoni B.; Trulsson, Mats

1992-07-01

321

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

322

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

323

The validity of periodontal probing as a method of measuring loss of attachment.  

Science.gov (United States)

Linear probe measurements are used to assess the severity and extent of attachment loss in chronic periodontitis and to identify, retrospectively, sites of disease activity. The use of the probe for these purposes is based on the implicit assumption that there is a direct and predictable relationship between linear probe measurements of attachment loss and the area of cemental surface which has been denuded of periodontal ligament. The aim of this study was to test this assumption by determining the correlation between loss of attachment as expressed by probe readings, and that expressed as the area of denuded root surface. The areas of denuded root surface of 236 teeth of different morphotype in 41 human dried skulls were determined by a rubber base impression technique and compared with their corresponding probe measurements, made at 10 sites per tooth. Although the majority of correlations between linear and area measurements were statistically significant for some individual morphotypes and categories of bone loss, there was overall, no consistent pattern of correlation between the two parameters. Furthermore, many correlations which were statistically significant had low values of the correlation coefficient: Kendall's T. It was concluded that probe readings are not a very precise measure of attachment loss, particularly with increasing severity destruction. These results cast doubt on the ability of individual linear measurements to represent the true severity of attachment loss, and thus on the precision of loss of attachment charts for retrospectively identifying sites of periodontal disease activity. PMID:1960233

Theil, E M; Heaney, T G

1991-10-01

324

[Oto-mandibular ligaments: disco-mallear and malleo-mandibular ligaments].  

Science.gov (United States)

Phylogenesis, embryology and anatomy are emphasizing that two ligaments are found between the temporo-mandibular joint and the middle ear. These two oto-mandibular ligaments are named the disco-mallear ligament and the malleo-mandibular ligament. Originating from the first arch, these ligaments are not involved in the otologic manifestations of the temporo-mandibular joint syndrome. The disco-mallear ligament is a brake applied to the anterior excursion of the disc. When this disco-mallear ligament is stretched the disc can be displaced anteriorly breeding disc displacement, hypermobility and temporo-mandibular dislocation. The malleo-mandibular ligament is a remainder of the Meckel's cartilage: its role is not clear. When excessive forces are applying on the mandible, ossicles dislocation can be seen the forces being transmitted through it. PMID:9324731

Gola, R; Chossegros, C; Cheynet, F

1997-08-01

325

Periodontal Disease and Pregnancy Outcomes  

OpenAIRE

An increasing number of studies are confirming an association between periodontal disease (PD) and adverse outcomes in pregnancy. PD places pregnant women at greater risk for preterm birth than alcohol consumption or smoking. This underscores the importance of offering dental screening to women who are pregnant or contemplating pregnancy and the need for physicians who provide obstetric care to be aware of the possible connection between poor dental health and poor pregnancy outcomes.

Babalola, Dolapo A.; Folashade Omole

2010-01-01

326

Diagnóstico educativo y capacitación periodontal  

Directory of Open Access Journals (Sweden)

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

327

Phagocyte function in juvenile periodontitis.  

OpenAIRE

We studied the chemotaxis of peripheral blood polymorphonuclear leukocytes (PMNs) and monocytes and the production of tumor necrosis factor alpha by monocytes of patients with juvenile periodontitis (JP). As a group, the patients' PMNs showed significantly increased chemotaxis determined by counting the number of migrating cells within a 3-microns-pore-size filter. Determined as distance of migration within the filter, as chemotactic increment based on checkerboard analysis, as leukotactic in...

Repo, H.; Saxe?n, L.; Ja?a?ttela?, M.; Ristola, M.; Leirisalo-repo, M.

1990-01-01

328

Characteristics of the three ligaments of human spring ligament complex from a viewpoint of elements.  

Science.gov (United States)

To elucidate characteristics of the three ligaments constituting the spring ligament complex from a viewpoint of elements, the authors investigated age-related changes of elements, relationships among their elements, relationships among ligaments in the elements, and gender differences in the three ligaments of the spring ligament complex, the superomedial calcaneonavicular (SMCN), inferoplantar longitudinal calcaneonavicular (ICN), and third or medioplantar oblique calcaneonavicular (TCN) ligaments. After ordinary dissection at Nara Medical University was finished, the SMCN, ICN, and TCN ligaments of the spring ligament complex were removed from the subjects. The subjects consisted of 10 men and 12 women, ranging in age from 62 to 99 years (average age = 80.5 ± 9.7 years). After incineration with nitric acid and perchloric acid, the element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was found that although the Ca and P content hardly changed in the SMCN ligament with aging, the Ca and P content in the ICN ligament increased to about three and five times higher in the 80s in comparison with the 60s, respectively, whereas in the TCN ligament, it increased about 40% and 90% higher in the 80s compared with the 60s, respectively. Regarding the relationships among elements, significant direct correlations were found among the contents of Ca, P, and Mg in all the three ligaments of the spring ligament complex. This finding was in agreement with the previous finding obtained with the three ligaments of the anterior cruciate ligament, posterior longitudinal ligament, and ligamentum capitis femoris. Whether there were significant correlations among the three ligaments of the spring ligament complex with regard to the Ca, P, S, Mg, Zn, and Fe contents was examined using Pearson's correlation. It was found that there were significant direct correlations between the SMCN and TCN ligaments in all the Ca, P, Mg, and Zn contents and also between the SMCN and ICN ligaments in both the Mg and Fe contents but not between the TCN and ICN ligaments in the six element contents. Regarding the gender difference in elements, a significant gender difference was found only in the Mg content of the SMCN ligament, being significantly higher in men than in women. PMID:22072216

Tohno, Yoshiyuki; Tohno, Setsuko; Taniguchi, Akira; Azuma, Cho; Minami, Takeshi; Mahakkanukrauh, Pasuk

2012-06-01

329

Gene Polymorphisms in Chronic Periodontitis  

Directory of Open Access Journals (Sweden)

Full Text Available We aimed to conduct a review of the literature for gene polymorphisms associated with chronic periodontitis (CP susceptibility. A comprehensive search of the literature in English was performed using the keywords: periodontitis, periodontal disease, combined with the words genes, mutation, or polymorphism. Candidate gene polymorphism studies with a case-control design and reported genotype frequencies in CP patients were searched and reviewed. There is growing evidence that polymorphisms in the IL1, IL6, IL10, vitamin D receptor, and CD14 genes may be associated with CP in certain populations. However, carriage rates of the rare (R-allele of any polymorphism varied considerably among studies and most of the studies appeared under-powered and did not correct for other risk factors. Larger cohorts, well-defined phenotypes, control for other risk factors, and analysis of multiple genes and polymorphisms within the same pathway are needed to get a more comprehensive insight into the contribution of gene polymorphisms in CP.

Marja L. Laine

2010-01-01

330

Strength loss in kraft pulping  

Science.gov (United States)

Unbleached kraft pulps from two U.S. mills were 21% and 26% weaker than comparable laboratory pulps from the same chip sources, when assessed as the tear index at a tensile index of 70 kN.m/kg. The phenomena involved were clarified by characterizing the differences between the mill and laboratory pulps in terms of fundamental fiber properties. All of the strength loss could be explained by a reduction in intrinsic fiber strength of 9% to 11%, as estimated from wet zero-span tensile tests and fiber length distributions. Most of the effects of different fiber shape and length were isolated by PFI mill refining and decrilling, respectively. The higher fiber coarseness of mill pulps was a factor in their maximum density and bond strength, but changes in these variables were analogous to those of laboratory pups due to similar swelling. Specific bond strength, determined from a wet pressing experiment, was similar in mill and laboratory pulps. Neither carbohydrate composition nor crystalline structure, assessed through x-ray diffraction analysis, were significant factors in the observed fiber strength differences. The mill pulps were not more heterogeneous than the laboratory pulps, within the resolution of a fractionation experiment. The number of weak points in each pulp was assessed through analysis of the amount of fiber cutting during PFI mill refining and treatments with potassium superoxide or cellulase. The results suggested that the chemistry of kraft pulping preferentially weaken short, slender fibers, while mechanical stresses during the hot discharge of batch digesters mainly affect long, thick fibers. The greater number of weak points in the long-fiber fractions of mill pulps is probably associated with their lower wet zero-span tensile indices. Automated optical detection of major singularities with a prototype instrument suggested that only the weak points induced by mechanical stress could be detected by local variations in birefringence. In contrast, chemically damaged short, slender fibers were not optically active. Strong chemical attack during superoxide treatment appeared to affect all fibers, but the effect of fiber cutting was partially offset by a preferential dissolution of short fibers and fines. A simple model of weak point formation by combinations of mechanical stress and localized chemical attack was sufficient to explain all the experimental results.

Iribarne, Jose

331

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

Directory of Open Access Journals (Sweden)

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

332

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

Directory of Open Access Journals (Sweden)

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

333

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 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; I, Retamal; M, Cáceres; A, Romero; D, Silva; R, Arancibia; C, Martínez.

2012-08-01

334

Filifactor alocis - involvement in periodontal biofilms  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Bacteria in periodontal pockets develop complex sessile communities that attach to the tooth surface. These highly dynamic microfloral environments challenge both clinicians and researchers alike. The exploration of structural organisation and bacterial interactions within these biofilms is critically important for a thorough understanding of periodontal disease. In recent years, Filifactor alocis, a fastidious, Gram-positive, obligately anaerobic rod was repeatedly identified in periodontal lesions using DNA-based methods. It has been suggested to be a marker for periodontal deterioration. The present study investigated the epidemiology of F. alocis in periodontal pockets and analysed the spatial arrangement and architectural role of the organism in in vivo grown subgingival biofilms. Results A species-specific oligonucleotide probe, FIAL, was designed and evaluated. A total of 490 subgingival plaque samples were submitted to PCR and subsequent dot blot hybridization to compare the prevalence of F. alocis in patients suffering from generalized aggressive periodontitis (GAP, chronic periodontitis (CP, and control subjects resistant to periodontitis. Moreover, a specially designed carrier system was used to collect in vivo grown subgingival biofilms from GAP patients. Subsequent topographic analysis was performed using fluorescence in situ hybridization. While the majority of patients suffering from GAP or CP harboured F. alocis, it was rarely detected in the control group. In the examined carrier-borne biofilms the organism predominantly colonized apical parts of the pocket in close proximity to the soft tissues and was involved in numerous structures that constitute characteristic architectural features of subgingival periodontal biofilms. Conclusions F. alocis is likely to make a relevant contribution to the pathogenetic structure of biofilms accounting for periodontal inflammation and can be considered an excellent marker organism for periodontal disease.

Göbel Ulf B

2010-03-01

335

[Laparoscopic management of median arcuate ligament syndrome].  

Science.gov (United States)

Median arcuate ligament syndrome is a rare disorder resulting from luminal narrowing of the celiac trunk. The classic management of median arcuate ligament syndrome involves the surgical division of the median arcuate ligament fibers in order to decompress the celiac trunk. This has traditionally required an upper midline incision. A few authors have described a successful laparoscopic release of celiac artery compression syndrome. Laparoscopy provides a less invasive, but equally effective method for decompressing the celiac trunk. PMID:18313874

Jarry, J; Berard, X; Ducasse, E; Biscay, D; Pailler, A; Sassoust, G; Midy, D; Baste, J-C

2008-02-01

336

[Median arcuate ligament syndrome: a controversial entity.].  

Science.gov (United States)

Median arcuate ligament syndrome is a disorder resulting from compression of the origin of the celiac trunk by the arcuate ligament, a fibrous arch that connects the right and left diaphragmatic crura. This is a controversial entity because the clinical manifestations are often nonspecific and isolated compression of the celiac trunk is relatively common in asymptomatic individuals. We report two cases of median arcuate ligament syndrome and review the radiographic features necessary for the imaging workup of this entity. PMID:19361828

Meilán Martínez, A; Jiménez de la Peña, M; Recio Rodríguez, M; Carrascoso Arranz, J

2009-01-01

337

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

338

Imaging of the anterior cruciate ligament  

OpenAIRE

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 A...

Wing Hung Alex Ng; James Francis Griffith; Esther Hiu Yee Hung; Bhawan Paunipagar; Billy Kan Yip Law; Patrick Shu Hang Yung

2011-01-01

339

Tissue Engineering Strategies in Ligament Regeneration  

OpenAIRE

Ligaments are dense fibrous connective tissues that connect bones to other bones and their injuries are frequently encountered in the clinic. The current clinical approaches in ligament repair and regeneration are limited to autografts, as the gold standard, and allografts. Both of these techniques have their own drawbacks that limit the success in clinical setting; therefore, new strategies are being developed in order to be able to solve the current problems of ligament grafting. Tissue eng...

Gazi Huri; Pinar Yilgor Huri; Caglar Yilgor

2011-01-01

340

Concordancia entre nivel de inserción clínico y examen radiográfico para diagnóstico de periodontitis crónica / Concordance between Clinical Attachment Level and Radiographic Examination for Diagnosis of Chronic Periodontitis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish Objetivo: Determinar la concordancia y relación entre el nivel de inserción clínico periodontal y el examen radiográfico en pacientes con periodontitis crónica. Métodos: Estudio de corte transversal en 135 participantes mayores de 16 años, seleccionados de forma aleatoria, con diagnóstico de periodo [...] ntitis crónica. De los cuales se obtuvieron 352 radiografías periapicales en 1292 sitios interproximales. Se midieron las alturas de las crestas alveolares con una regla milimetrada. Además se examinaron el tipo de defecto, la continuidad de la lámina dura y el ensanchamiento del espacio del ligamento periodontal. Los datos fueron analizados a través de medidas de tendencia central y dispersión. Para cuantificar la concordancia se utilizó la prueba Kappa y para las relaciones se utilizaron las razones de odds con intervalos de confianza del 95%, además para establecer significancia se utilizó la prueba ?² asumiendo un límite de decisión de 0,05. Resultados: Se encontró una relación estadísticamente significativa entre los niveles de inserción 4, 5 y 6 mm y la pérdida ósea radiográfica. Para las demás relaciones no hubo significancia estadística. Con respecto al tipo de defecto, el horizontal fue el más común con un 23% de los sitios examinados. Conclusión: Para el diagnóstico de periodontitis crónica no es suficiente con la valoración del examen radiográfico, porque en niveles de inserción 1, 2 y 3 mm no se presenta pérdida ósea visible. Es evidente que al utilizar solamente este método diagnóstico se aumentaría los falsos negativos, subregistrándose la enfermedad. Abstract in english Objective: Determine the concordance and relationship between periodontal clinical attachment level and radiographic examination in patients with chronic periodontitis. Methods: Cross-sectional study of 135 participants over 16 years, randomly selected, diagnosed with chronic periodontitis. Of which [...] 352 were obtained in 1292 periapical interproximal sites. It was measured the height of the ridge with a millimeter ruler. Furthermore, were examined the type of defect, the continuity of the lamina dura and widening of the periodontal ligament space. The data were analyzed using measures of central tendency and dispersion. To quantify the correlation test was used for Kappa and relationships were used odds ratios with confidence intervals of 95%, and was used to establish significance Chi-square test assuming a decision limit of 0.05. Results: There was a statistically significant relationship between attachment levels 4, 5 and 6 mm and radiographic bone loss. For the other relationships were not statistically significant. Regarding the type of defect, the horizontal pattern loss was the most common with 23% of the sites examined. Conclusion: For the diagnosis of chronic periodontitis is not enough with the assessment of radiographic examination, because attachment levels 1, 2 and 3 mm bone loss occurs not visible. It is clear that using only this method of diagnosis would increase the false negative underreported disease.

A.J., Díaz Caballero; F.D., González Martínez; L.L., Arévalo Tovar.

2012-08-01

341

Psychosocial distress and periodontitis in adolescents  

DEFF Research Database (Denmark)

Periodontitis is an inflammatory disease associated with predominantly gram negative biofilms and characterized by the progressive destruction of the supporting tissues of the teeth. Some studies conducted among adults have found a significant association between periodontitis and dimensions of psychosocial distress and it is unclear whether this association can be found among younger subjects in which destruction of periodontal tissues as a result of periodontitis are less severe. Purpose: The main aim of this study was to assess whether adolescents with periodontitis presented with higher scores for non-psychotic psychosocial disorders than control subjects without periodontitis. Materials and Methods: We used a case control study (n=160) nested in a well-defined adolescent population (n=9,163) and the 28-item Spanish version of the General Health Questionnaire. The inclusion criterion for being a case was clinical attachment level ? 3 mm in at least two teeth. Multiple logistic regression analyses were used to assess the association between periodontitis and psychosocial distress. Results: The response rate was high and 94% of the participants answered all the items of the questionnaire. Similarly, the internal consistency of the instrument was high (Cronbach’s ? = 0.91). The results of multiple logistic regression analyses, adjusted for age and gender, suggested an association between case status and higher total scoring for psychosocial distress (OR=1.69). Among the four subdomains of General Health Questionnaire, the dimensions ‘somatic symptoms’ and ‘severe depression’ appeared positively associated with periodontal case status though not significantly.

Lopez, Rodrigo; Ramírez, Valeria

2012-01-01

342

Dissolving pulp from jute stick.  

Science.gov (United States)

Jute stick is woody portion of jute plant, which remain as leftover after extracting bast fibre. Presently, it is being used for fencing in the rural area. In this investigation, biorefinery concept was initiated in producing dissolving pulp from jute stick by pre-hydrolysis kraft process. At 170°C for 1h of pre-hydrolysis, 70% of hemicelluloses was dissolved with negligible loss of ?-cellulose. At this condition, 75% of dissolved sugars in the pre-hydrolysis liquor were in the oligomeric form. The pre-hydrolysed jute stick was subsequently pulped by kraft process with the variation of active alkali. The pulp yield was 36.2% with kappa number 18.5 at the conditions of 16% active alkali for 2h of cooking at 170°C. Final pulp was produced with 92% ?-cellulose and 89% brightness after D0EpD1EpD1 bleaching. The produced dissolving pulp can be used in rayon production. PMID:25439866

Matin, Mhafuza; Rahaman, M Mostafizur; Nayeem, Jannatun; Sarkar, Mamon; Jahan, M Sarwar

2015-01-22

343

Anti-Nanobacterial Therapy for Prevention and Control of Periodontal Diseases  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction: Nanobacteria have been implicated in the formation of pathogenic calcifications e.g. kidney stones, arterial plaque, calcified cardiac valves, dental pulp stone, etc. It has been hypothesized that nanobacteria may be present in dental calculus which has a similar mineralization formation process and that nanobacteria may play an efficient role in the calcification of dental calculus. Recently nanobacteria were found in gingival crevicular fluid samples from two subjects with chronic periodontitis.The hypothesis: An anti-nanobacterial mouthwash or tooth paste containing bisphosphonates specifically etidronate and clodronate (1 mg/ml, gallium nitrate 14% (3.4% w/w gallium at 99.995% purity and ethylenediaminetetraacetic acid (1% with neutral pH (7.0 will may be effective for prevention of calculus formation and consequently prevention of periodontal diseases. Despite of excellent anti-nanobacterial activity of tetracycline, it is removed from the formulation. It has a wide spectrum of anti-bactericidal activity and may affect normal oral flora and cause supra-infection. Evaluation of the hypothesis: We should consider a balance between negative effect of nanobacteria regarding formation of calculus and periodontal diseases and positive role of nanobacteria in enamel repair and prevention of dental caries and its positive role in enamel repair and prevention of dental caries.

Jafar Kolahi

2010-03-01

344

Periodontal disease and atherosclerosis / Doença periodontal e aterosclerose  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Languages: English, Portuguese Abstract in portuguese A doença aterosclerótica (DA) constitui uma das principais causas de morbimortalidade no mundo. A sua expressão laboral pode ser através de marcadores inflamatórios, como a proteína C reativa (PCR) e/ou o espessamento da parede arterial, que pode ser analisado pela ultrassonografia com Doppler color [...] ido. Os fatores de risco associados à DA são o diabetes mellitus, a hipertensão arterial sistêmica, a dislipidemia e o tabagismo. Mais recentemente, a doença periodontal (DP), que tem uma elevada prevalência na população mundial, tem sido considerada um fator relacionado ao desenvolvimento da DA, em que o processo inflamatório e a atividade bacteriana no periodonto parecem aumentar o risco para a DA. A motivação da higiene oral pode diminuir a expressão dos marcadores inflamatórios da DA. Com base em dados publicados em revistas eletrônicas e indexados pelos mecanismos de busca PUBMED, SCIELO e BIREME, foi realizada uma revisão de literatura sobre a DP e a DA, além dos marcadores inflamatórios expressos em ambas as doenças e suas possíveis inter-relações. Abstract in english Atherosclerotic disease (AD) is one of the most important causes of morbidity and mortality in the world. It expresses inflammatory markers such as C-reactive protein (CRP) and can provoke arterial wall thickening, which can be evaluated using Doppler ultrasound. Risk factors associated with AD incl [...] ude diabetes mellitus, systemic arterial hypertension, dyslipidemia and smoking. More recently, periodontal disease (PD) has been identified as a factor related to AD. Periodontal disease has a high prevalence in the global population and the inflammatory process and bacterial activity at the periodontium appear to increase the risk of AD. Encouraging good oral hygiene can reduce expression of inflammatory markers of AD. A review of literature on PD, AD and inflammatory markers and the interrelationships between the two diseases was conducted using data published in articles indexed on the PUBMED, SCIELO and BIREME databases.

Jeferson Freitas, Toregeani; Carlos Augusto, Nassar; Krischina Aparecida Mendes, Toregeani; Patrícia Oehlmeyer, Nassar.

2014-09-01

345

Some modern aspects of periodontal disease  

International Nuclear Information System (INIS)

During the last three to four decades, extensive changes in opinion concerning the etiology, pathogenesis, and treatment of periodontal disease have taken place. During these decades, contributing factors are standardized and controlled trials, as well as epidemiological studies, were performed. Periodontics is no longer an art as it was at the end of the 19th century- it is a science based on research. Pyorrhea alveoiaris or periodontitis has been considered a multifactorial disease with bad prognosis which, together with caries, causes loss of teeth in the population. It was supposed to affect most of the population with age progress, trauma from occlusion, systemic diseases, and bad oral hygiene. The discovery that plaque was the cause of gingivitis, and that the subgingival microflora differed in composition between sites, teeth, and individuals created new suggestions and demands for the treatment of periodontal disease. The aim of this paper is to summarize some modern aspects on periodontal disease. (author)

346

Role of Stress in Periodontal Disease  

Directory of Open Access Journals (Sweden)

Full Text Available Psychological stress, if sustained over an extended period of time can have deleterious effects on the body representing an example of the mind-body interaction. Human and animal studies have shown that dental plaque bacteria are important for the development of gingivitis and periodontitis in both healthy and immunocompromised humans. As with many chronic infections the onset and progression of periodontal infections are clearly modified by local and systemic host conditions or risk factors that markedly affect the resistance of the host to infecting periodontal organisms. Psychological conditions, particularly psychological stress have been implicated as risk indicators for periodontal disease. This article reviews the current literature with emphasis on the potential role of psychological stress in periodontal disease progression.

Ramesh Reddy B V

2012-04-01

347

Association between Human Body Composition and Periodontal Disease  

OpenAIRE

Obesity in humans might increase the risk of periodontitis. The aim of the present study was to examine the relationship between body composition of males and their periodontal status. AS total of 150 males (aged 30–60) were selected: 31 were periodontally healthy, 45 had gingivitis, 39 had initial periodontitis, and 35 suffered from ...

Farough Nayebi; Mohammad Rahbar; Adileh Shirmohammadi; Yagoub Salekzamani; Seyed-kazem Shakouri

2011-01-01

348

Methanol-based pulping of Eucalyptus globulus  

Energy Technology Data Exchange (ETDEWEB)

The dissolution of wood components using organosolv pulping was discussed. Solvents such as ethanol and methanol can provide more efficient utilization of the lignocellulosic feedstock, ease of bleachability, and lower capital production costs compared to the kraft process. In this study, the autocatalyzed pulping of Eucalyptus globulus wood in a methanol-water media was examined. The influence of pulping temperature, pulping time and methanol concentration on pulp properties were determined by a surface response method. One of the advantages of using methanol pulping of hardwoods compared to ethanol pulping is the low boiling point of methanol which makes its recovery easy from pulping black liquor by distillation. The price of methanol is also very low compared to other solvents. The optimum pulping conditions were found to be a cooking temperature of 185 degrees C, a cooking time of 110 minutes and a methanol concentration of 50 per cent. These conditions yielded a pulp with a low kappa number and a viscosity value of 110 mL/g. When ethanol pulping was used under the same conditions, the resulting pulp had a higher kappa number and a lower viscosity. 27 refs., 2 tabs., 8 figs.

Gilarranz, M.A.; Oliet, M.; Rodriguez, F.; Tijero, J. [Universidad Complutense de Madrid, Madrid (Spain). Dept. de Ingenieria Quimica

1999-06-01

349

21 CFR 872.1720 - Pulp tester.  

Science.gov (United States)

...2010-04-01 2010-04-01 false Pulp tester. 872.1720 Section 872.1720 Food and...DEVICES Diagnostic Devices § 872.1720 Pulp tester. (a) Identification. A pulp tester is an AC or battery powered device...

2010-04-01

350

Enzymatic hydrolysis of potato pulp  

Directory of Open Access Journals (Sweden)

Full Text Available Background. Potato pulp constitutes a complicated system of four types of polysaccharides: cellulose, hemicellulose, pectin and starch. Its composition makes it a potential and attractive raw material for the production of the second generation bioethanol. The aim of this research project was to assess the usefulness of commercial enzymatic preparations for the hydrolysis of potato pulp and to evaluate the effectiveness of hydrolysates obtained in this way as raw materials for ethanol fermentation. Material  and methods. Sterilised potato pulp was subjected to hydrolysis with commercial enzymatic preparations. The effectiveness of the preparations declared as active towards only one fraction of potato pulp (separate amylase, pectinase and cellulase activity and mixtures of these preparations was analysed. The monomers content in hydrolysates was determined using HPLC method. Results.  The application of amylolytic enzymes for potato pulp hydrolysis resulted in the release of only 18% of raw material with glucose as the dominant (77% constituent of the formed product. In addition, 16% galactose was also determined in it. The hydrolysis of the cellulose fraction yielded up to 35% raw material and the main constituents of the obtained hydrolysate were glucose (46% and arabinose (40%. Simultaneous application of amylolytic, cellulolytic and pectinolytic enzymes turned out to be the most effective way of carrying out the process as its efficiency in this case reached 90%. The obtained hydrolysate contained 63% glucose, 25% arabinose and 12% other simple substances. Conclusion. The application of commercial enzymatic preparations made it possible to perform potato pulp hydrolysis with 90% effectiveness. This was achieved by the application of a complex of amylolytic, cellulolytic and pectinolytic enzymes and the hydrolysate obtained in this way contained, primarily, glucose making it a viable substrate for ethanol fermentation.

Mariusz Lesiecki

2012-03-01

351

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.)

352

APPLICATION OF SURFACTANTS AS PULPING ADDITIVES IN SODA PULPING OF BAGASSE  

OpenAIRE

The effects of several non-ionic commercial surfactants and their dosage on soda pulping and ECF bleaching of soda and soda-surfactant pulps of bagasse were investigated. The properties of bleachable pulps obtained with conventional soda and with soda-surfactants were studied and compared. The results showed application of surfactants during the soda pulping of bagasse decreased kappa number and improved the yield and brightness of resulting pulp. Using the surfactants reduced alkali consumpt...

Yahya Hamzeh; Ali Abyaz; Mahsa O-Sadat Mirfatahi Niaraki; Ali Abdulkhani

2009-01-01

353

RANKL Expression in Periodontal Disease: Where Does RANKL Come from?  

OpenAIRE

Periodontitis is an inflammatory disease characterized by periodontal pocket formation and alveolar bone resorption. Periodontal bone resorption is induced by osteoclasts and receptor activator of nuclear factor-?B ligand (RANKL) which is an essential and central regulator of osteoclast development and osteoclast function. Therefore, RANKL plays a critical role in periodontal bone resorption. In this review, we have summarized the sources of RANKL in periodontal disease and explored which fa...

Bin Chen; Wenlei Wu; Weibin Sun; Qian Zhang; Fuhua Yan; Yin Xiao

2014-01-01

354

Recent advances in periodontal drug delivery systems.  

Directory of Open Access Journals (Sweden)

Full Text Available

Periodontitis, a disease involving supportive structures of the teeth prevails in all groups, ethnicities, races and both genders. The relationship between bacterial plaque and the development of periodontal disease and caries is well established. Antibacterial agents have been used effectively in the management of periodontal infection. The effectiveness of mechanical debridement of plaque and repeated topical and systemic administration of antibacterial agents are limited due to the lack of accessibility to periodontopathic organisms in the periodontal pocket. Systemic administration of drugs leads to therapeutic concentrations at the site of infection, but for short periods of time, forcing repeated dosing for longer periods. Local delivery of antimicrobials has been investigated for the possibility of overcoming the limitations of conventional therapy. The use of sustained release formulations to deliver antibacterials to the site of infection (periodontal pocket has recently gained interest. These products provide a long-term, effective treatment at the site of infection at much smaller doses. Biodegradable polymers are extensively employed in periodontal drug delivery devices because of their abundant source, lack of toxicity, and high tissue compatibility. A major advantage of natural polymers is that they do not affect periodontal tissue regeneration. Amongst various natural polymers, chitosan, a deacetylated product of chitin is widely used in drug delivery devices. Since it exhibits favourable biological properties such as non-toxicity, biocompatibility, biodegradability and wound healing traits, it has attracted great attention in the pharmaceutical and biomedical fields. The conventional treatment consists of tooth surface mechanical cleaning and root planning, associated or not to the systemic use of high concentrations of antibiotics, but with reduced effectiveness, and adverse effects. The patient compliance to the therapeutic is committed too. In the last decades, the treatment has been optimized for the use of drug delivery systems to the periodontal pocket, with the advantage of delivering the drug in the specific site, sustaining and/or controlling the drug concentration. Recently, the use of new drug delivery systems has been receiving great interest. This review approaches the main delivery systems for the administration of drugs to the periodontal pocket, their usefulness, as well as the advancement of these systems effectiveness in the periodontal therapy.

Keywords : Periodontal diseases; Periodontal pocket; Delivery systems; Periodontal pocket delivery

Pragati S

2011-04-01

355

Relationship between the Pathogenic Representatives of Periodontal Pockets Microbiocenosis in Patients with Periodontitis with Varying Degrees of Severity  

OpenAIRE

Periodontitis is a common disease that is considered to be a manifestation of the distortion of the ratio between the normal and conditionally pathogenic microflora of periodontal pockets. In this study, the ratio between the six most important periodontal pathogens and the total microflora of the periodontal pocket in healthy individuals and patients with varying severity of periodontitis was ascertained by quantitative real-time PCR. It was ascertained that the relative content ofPorphyromo...

Zorina, O. A.; Kulakov, A. A.; Boriskina, O. A.; Rebrikov, D. V.

2011-01-01

356

Combined periodontic-orthodontic-endodontic interdisciplinary approach in the treatment of periodontally compromised tooth  

OpenAIRE

Orthodontic treatment in adult patients is one of the most frequently encountered components involving multidisciplinary approaches. In the present report, a 28-year-old male patient was treated for localized chronic periodontitis with pocket formation, mobility, pathologic migration and malalignment of maxillary left lateral incisor tooth #22. The periodontal therapy included motivation, education and oral-hygiene instructions (O.H.I.), scaling and root planing and periodontal flap surgery. ...

Deepa D; Mehta D; Puri Viren; Shetty Sadashiva

2010-01-01

357

The clinical course of chronic periodontitis: V. Predictive factors in periodontal disease  

OpenAIRE

Background: The factors associated with initial periodontitis are not well understood and cannot be identified by cross-sectional studies. Aim: To identify the factors associated with the initiation of chronic periodontitis using ante-dependence modelling. Material & Methods: A 26-year longitudinal study of the natural history of periodontitis served as the basis for the study. In 1969, 565 Norwegian men aged 16 to 34 years were surveyed. Subsequent surveys were performed in 1971, 1973,...

Scha?tzle, M.; Faddy, M. J.; Cullinan, M. P.; Seymour, G. J.; Lang, N. P.; Bu?rgin, W.; A?nerud, A?; Boysen, H.; Lo?e, H.

2009-01-01

358

Tooth loss in aggressive periodontitis after active periodontal therapy. Patient and tooth related prognostic factors  

OpenAIRE

Abstract Objectives: To assess prognostic factors for tooth loss after active periodontal therapy (APT) in patients with aggressive periodontitis (AgP) on tooth-level. Material and Methods: 84 patients with AgP were re-evaluated after a mean period of 10.5 years of Supportive Periodontal Therapy (SPT). 2154 teeth were entered into the model. The tooth-related factors: baseline bone loss, tooth location and type, furcation involvement (FI), regenerative therapy, and abutment sta...

Ba?umer, Amelie; Pretzl, Bernadette; Cosgarea, Raluca; Kim, Ti-sun; Reitmeir, Peter; Eickholz, Peter; Dannewitz, Bettina

2011-01-01

359

Periodontitis and coronary artery disease: a questioned association between periodontal and vascular plaques  

OpenAIRE

Periodontitis is a bacterially-induced, localized chronic inflammatory disease destroying both the connective tissue and the supporting bone of the teeth. In the general population, severe forms of the disease demonstrate a prevalence of almost 5%, whereas initial epidemiological evidence suggests an association between periodontitis and coronary artery disease (CAD). Both the infectious nature of periodontitis and the yet etiologically unconfirmed infectious hypothesis of CAD, question their...

Thomopoulos, Costas; Tsioufis, Costas; Soldatos, Nikos; Kasiakogias, Alexandros; Stefanadis, Christodoulos

2011-01-01

360

Prevalence of Clinical Periodontitis and Putative Periodontal Pathogens among South Indian Pregnant Women  

OpenAIRE

In view of recent understanding of the association of periodontal infections and adverse pregnancy outcomes, the present investigation was undertaken to study the periodontal infections among 390 asymptomatic pregnant women and to find an association of bacterial etiologies with the disease. Prevalence of gingivitis was 38% and clinical periodontitis was 10% among the study population. Subgingival plaque specimens were subjected to multiplex PCR targeting ten putative periodontopathogenic bac...

Chaitanya Tellapragada; Vandana Kalwaje Eshwara; Shashidhar Acharya; Parvati Bhat; Asha Kamath; Shashidhar Vishwanath; Chiranjay Mukhopadhyay

2014-01-01

361

Periodontitis and coronary artery disease : Studies on the association between periodontitis and coronary artery disease  

OpenAIRE

Periodontitis and coronary artery disease (CAD) are highly prevalent in Sweden’s population; both diseases have complicated pathogeneses and clinical manifestations due to immune-system triggered inflammation. Research in recent years reported that inflammation is a significant active participant in many chronic diseases. The literature described a CAD-periodontitis association, but underlying mechanisms are not fully understood. It is important to acquire knowledge about how periodontitis ...

Starkhammar Johansson, Carin

2012-01-01

362

Smoking and periodontal tissues: a review  

Scientific Electronic Library Online (English)

Full Text Available The impact of smoking on general health has been widely studied and is directly related to several important medical problems including cancer, low birth weight, and pulmonary and cardiovascular disease. In the past 25 years, there has also been an increasing awareness of the role of cigarette consu [...] mption in oral health problems such as periodontal disease. Smoking is considered the major risk factor in the prevalence, extent and severity of periodontal diseases. This article will discuss the available evidence and provide the reader with an overview of the impact of smoking and its cessation on the pathogenesis and treatment of periodontal diseases.

João Batista, César Neto; Ecinele Francisca, Rosa; Cláudio Mendes, Pannuti; Giuseppe Alexandre, Romito.

363

Association between periodontal diseases and systemic diseases  

Directory of Open Access Journals (Sweden)

Full Text Available Current evidence suggests that periodontal disease may be associated with systemic diseases. This paper reviewed the published data about the relationship between periodontal disease and cardiovascular diseases, adverse pregnancy outcomes, diabetes and respiratory diseases, focusing on studies conducted in the Brazilian population. Only a few studies were found in the literature focusing on Brazilians (3 concerning cardiovascular disease, 7 about pregnancy outcomes, 9 about diabetes and one regarding pneumonia. Although the majority of them observed an association between periodontitis and systemic conditions, a causal relationship still needs to be demonstrated. Further studies, particularly interventional well-designed investigations, with larger sample sizes, need to be conducted in Brazilian populations.

Patrícia Weidlich

2008-08-01

364

Relationship between invasion of the periodontium by periodontal pathogens and periodontal disease: a systematic review.  

Science.gov (United States)

Bacterial invasion of the periodontal tissues has been suggested as a relevant step in the etiopathogenesis of periodontal disease. However, its exact importance remains to be defined. The present systematic review assessed the scientific evidence concerning the relationship between the quality or quantity of periodontal microbiota in periodontal tissues and development of periodontal disease. The databases Medline-PubMed, Cochrane-CENTRAL, ISI Web of Knowledge and SCOPUS were searched, up to January 2014. Studies that reported evaluation of periodontal pathogens invasion on human tissues were selected. The screening of 440 title/abstracts elected 26 papers for full-text reading. Twenty three papers were subsequently excluded because of insufficient data or a study protocol not related to the objectives of this systematic review. All included studies were case-control studies that evaluated intracellular or adherent bacteria to epithelial cells from periodontal pockets versus healthy sulci. Study protocols presented heterogeneity regarding case and control definitions and methodological approaches for microbial identification. No consistent significant differences were found related to the presence/absence or proportion of specific periopathogens across the studies, as only one study found statistically significant differences regarding the presence of A. actinomycetemcomitans (p = 0.043), T. forsythia (P design, poor reporting and methodological diversity. As so, there is insufficient evidence to support or exclude the invasion by periodontal pathogens as a key step in the etiopathogenesis of periodontal disease. Further research is needed. PMID:25654367

Mendes, Luzia; Azevedo, Nuno Filipe; Felino, António; Pinto, Miguel Gonçalves

2015-04-01

365

Effect of Periodontal Therapy on Crevicular Fluid Interleukin-6 and Interleukin-8 Levels in Chronic Periodontitis  

OpenAIRE

Purpose. The aim of this study was to analyse the levels of interleukin-6 (IL-6) and interleukin-8 (IL-8) in gingival crevicular fluid (GCF) of patients with chronic periodontitis prior to and following surgical and/or nonsurgical periodontal therapy for a period of 32 weeks. Methods. GCF samples were obtained from 24 nondiseased and 72 diseased sites of 12 periodontal patients prior to as well as at 6, 16, and 32 weeks following non-surgical and surgical periodontal therapy. IL-6 and IL-8 le...

Paschalina Goutoudi; Evdoxia Diza; Malamatenia Arvanitidou

2011-01-01

366

Prevalence of Clinical Periodontitis and Putative Periodontal Pathogens among South Indian Pregnant Women  

Science.gov (United States)

In view of recent understanding of the association of periodontal infections and adverse pregnancy outcomes, the present investigation was undertaken to study the periodontal infections among 390 asymptomatic pregnant women and to find an association of bacterial etiologies with the disease. Prevalence of gingivitis was 38% and clinical periodontitis was 10% among the study population. Subgingival plaque specimens were subjected to multiplex PCR targeting ten putative periodontopathogenic bacteria. Among the periodontitis group, high detection rates of Porphyromonas gingivalis (56%), Prevotella nigrescens (44%), Treponema denticola (32%), and Prevotella intermedius (24%) were noted along with significant association with the disease (P < 0.05). PMID:24899898

Tellapragada, Chaitanya; Eshwara, Vandana Kalwaje; Acharya, Shashidhar; Bhat, Parvati; Kamath, Asha; Vishwanath, Shashidhar; Mukhopadhyay, Chiranjay

2014-01-01

367

Tratamiento periodontal quirúrgico: Revisión. Conceptos. Consideraciones. Procedimientos. Técnicas / Periodontal surgical therapy: Review. Concepts. Considerations. Procedures. Techniques  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish El tratamiento global de pacientes con enfermedad periodontal se divide en tres fases diferentes que, con frecuencia, se superponen: fase de terapia causal o fase inicial y la fase correctiva o fase de soporte periodontal o de mantenimiento. Como la mayoría de las formas de enfermedad periodontal so [...] n trastornos relacionados con la placa bacteriana, el tratamiento periodontal quirúrgico está considerado como un auxiliar del tratamiento periodontal causal inicial. Así mismo, la decisión respecto a qué tipo de cirugía periodontal debe realizarse, cuántas localizaciones deben incluirse y en qué momento del tratamiento, se adopta tras haberse evaluado el efecto de las medidas iniciales relacionadas con la causa. El objetivo principal del tratamiento periodontal quirúrgico es la preservación a largo plazo del periodonto. La cirugía periodontal puede contribuir, a este propósito, creando accesibilidad para el raspado y alisado radicular correctos, realizados por el profesional y al restablecer una morfología gingival que facilita el autocontrol de placa por parte del paciente. Las diversas técnicas quirúrgicas desarrolladas a lo largo del tiempo deben evaluarse sobre la base de su potencial para facilitar la eliminación de los depósitos subgingivales, bien como facilitar el autocontrol de la placa y así mejorar la preservación a largo plazo del periodonto. En el presente artículo se pretende realizar una revisión de los fundamentos del tratamiento periodontal quirúrgico, conceptos y consideraciones, objetivos, indicaciones y contraindicaciones, procedimientos y factores que determinan la elección de una u otra técnica quirúrgica. Abstract in english Periodontal treatment can be divided in three different phases most frequently superposed: cause-related or initial phase, corrective phase and supportive periodontal phase. Because the majority of these pathologies are related to plaque accumulation, periodontal surgical treatment might only be con [...] sidered as an adjunct to cause-related periodontal therapy. The kind of surgery performed, the number of sites included and the moment at which it should performed is decided after evaluating for the initial cause-related therapy results. The ultimate objective of periodontal surgical treatment is the long term preservation of the periodontium. Periodontal surgery can contribute to this end creating accessibility for an adequate scaling and root planning therefore restoring the gingival morphology which facilitates the automatic plaque control of the patient. Developed surgical techniques must be evaluated on the basis of their potential to facilitate the elimination of subgingival deposits, as well as facilitate plaque control and thus improve the long term preservation of the periodontium. In the present article the authors review the basis of surgical periodontal treatment as well as related concepts and considerations, objectives, indications and contraindications, procedures and factors that determine the selection of one or the other surgical technique.

R., Matos Cruz; A., Bascones-Martínez.

2011-12-01

368

Effect of Non-Surgical Periodontal Therapy on Interleukin-29 Levels in Gingival Crevicular Fluid of Chronic Periodontitis and Aggressive Periodontitis Patients  

OpenAIRE

Recently discovered interleukin 29 (IL-29) has antiviral properties and its production is induced by herpes viruses. This study was aimed at analyzing the effect of non-surgical periodontal treatment on IL-29 levels in gingival crevicular fluid (GCF) of chronic and aggressive periodontitis patients. A total of 60 participants were divided into healthy group (group 1; n = 20), chronic periodontitis group (group 2; n = 20), and aggressive periodontitis group (group 3; n = 20). GCF samples colle...

Shivaprasad, B. M.; Pradeep, A. R.

2013-01-01

369

Functional development of the sheep diaphragmatic ligament.  

Science.gov (United States)

1. The diaphragmatic ligament, which lines the thoracic surface of the diaphragm, plays a major role in setting the passive compliance of the diaphragm in the adult. Since many elastic tissues are more compliant at younger ages, our aim was to determine whether this diaphragmatic ligament plays an important role during development of the diaphragm. 2. We examined the passive biaxial length-tension properties of the isolated mid-costal diaphragm from fetal, newborn and adult sheep; initially with the diaphragm intact and then with the diaphragmatic ligament removed to reveal its functional significance. 3. We found that unlike other elastic tissues the diaphragmatic ligament is stiffer in early development than in the adult. The diaphragmatic ligament supports about 75% of the passive tension in the diaphragm in the 121 day fetus (term at 147 days) declining to about 50% from 3 weeks of age. The fetal diaphragm muscle fibres are exposed to 1-7 kPa of stress over the last 26 days of gestation. 4. We suggest that the diaphragmatic ligament provides a structural framework on which the muscle fibres of the diaphragm grow in fetal life, and that the ligament's elasticity is regulated to maintain a low and constant stress on the diaphragm muscle fibres during development. PMID:8735001

Griffiths, R I; Berger, P J

1996-05-01

370

MR imaging of posttraumatic spinal ligament injury  

International Nuclear Information System (INIS)

The accuracy of MR imaging in the detection of ligamentous injury was evaluated in 29 patients (24 male, five female) with spinal injury resulting in fractures (n=27), evidence of instability (n=11), or neurologic deficit (n=2). MR examinations were performed acutely (average, 7.5 days posttrauma) with T1- and T2-weighted imaging and were blindly evaluated. Subsequently, plain films (n=27), tomograms (n=10), and CT scans (n=22) were evaluated. Eighteen patients underwent surgery. Fourteen patients had torn ligaments as indicated by clinical and surgical findings. MR imaging demonstrated ligament damage in 13. One case imaged 40 days following trauma was not detected. No patients with intact ligaments had evidence of ligamentous damage on MR images. MR imaging demonstrated retropulsed fractures in six patients in whom the posterior longitudinal ligament was intact but displaced from the vertebra. MR imaging was more reliable than radiography and CT for detection of ligamentous injury, and T2- weighted sequences are essential in such cases

371

Chronic injuries of the cruciate ligaments  

International Nuclear Information System (INIS)

The high incidence of cruciate ligament injuries as a result of acute knee trauma with hemartrosis and abuse of diagnostic arthroscopies call for a suitable radiological imaging of the central pivot. Computed Arthrotomography (CAT) was used to examine the knee joint in 20 cases of clinically suspected chronic cruciate ligament injury. The images were correlated with arthroscopic and/or arthrotomic findings. Thirteen lesions of the anterior cruciate ligament (ACL) (65%) were found, plus 1 lesion of the posterior cruciate ligament (PCL) (5%), 2 associated lesions of ACL + PCL (10%), and 4 normal cases. Confirmation of pathology was available in all cases but one by arthroscopy and/or surgery. The central pivot diseases were classified as follows: absence, detachement, partial or complete tear. CAT findings of cruciate ligament injuries are emphasized and the role of the technique as compared to arthroscopy is discussed. CAT is useful in 3-D evaluation of central pivot and detection of different cruciate ligament injuries, with high sensitivity-specifity for ACL and high specifity-moderate sensitivity for PCL. In the evaluation of the chronic unstable knee, CAT is highly accurate and gives the surgeon useful information towards the planning of therapeutic procedures. CAT is almost non-invasive, well tolerated and easy to perform in out-patients, which make it a first-choice procedure in the screening of chronic ligament injuries

372

Functional tissue engineering of ligament healing  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Ligaments and tendons are dense connective tissues that are important in transmitting forces and facilitate joint articulation in the musculoskeletal system. Their injury frequency is high especially for those that are functional important, like the anterior cruciate ligament (ACL and medial collateral ligament (MCL of the knee as well as the glenohumeral ligaments and the rotator cuff tendons of the shoulder. Because the healing responses are different in these ligaments and tendons after injury, the consequences and treatments are tissue- and site-specific. In this review, we will elaborate on the injuries of the knee ligaments as well as using functional tissue engineering (FTE approaches to improve their healing. Specifically, the ACL of knee has limited capability to heal, and results of non-surgical management of its midsubstance rupture have been poor. Consequently, surgical reconstruction of the ACL is regularly performed to gain knee stability. However, the long-term results are not satisfactory besides the numerous complications accompanied with the surgeries. With the rapid development of FTE, there is a renewed interest in revisiting ACL healing. Approaches such as using growth factors, stem cells and scaffolds have been widely investigated. In this article, the biology of normal and healing ligaments is first reviewed, followed by a discussion on the issues related to the treatment of ACL injuries. Afterwards, current promising FTE methods are presented for the treatment of ligament injuries, including the use of growth factors, gene delivery, and cell therapy with a particular emphasis on the use of ECM bioscaffolds. The challenging areas are listed in the future direction that suggests where collection of energy could be placed in order to restore the injured ligaments and tendons structurally and functionally.

Hsu Shan-Ling

2010-05-01

373

Four-strand hamstring tendon autograft versus LARS artificial ligament for anterior cruciate ligament reconstruction  

OpenAIRE

This retrospective study compared the results after anterior cruciate ligament (ACL) reconstruction using a four-strand hamstring tendon graft (4SHG) versus Ligament Advanced Reinforcement System (LARS) artificial ligament in 60 patients between January 2003 and July 2004 with a minimum four-year follow-up. The KT-1000 examination, the International Knee Documentation Committee (IKDC) scoring systems and Lysholm knee scoring scale were used to evaluate the clinical results. The mean side-to-s...

Liu, Zhong-tang; Zhang, Xian-long; Jiang, Yao; Zeng, Bing-fang

2009-01-01

374

Medial collateral ligament injuries in athletes.  

Science.gov (United States)

Medial collateral ligament (MCL) sprains are tension injuries to the medial ligamentous structures of the knee. They are usually the result of an acute blow to the lateral aspect of the knee. The diagnosis can usually be made on the basis of a characteristic clinical examination. The treatment of these injuries has evolved over several years. Current recommended treatment for isolated MCL sprains is lightweight support and an aggressive early functional rehabilitation programme. In combined injuries, cruciate ligaments are usually surgically reconstructed and the MCL treated non-operatively. Although many braces have been developed to prevent MCL sprains, their effectiveness is uncertain. PMID:8775518

Reider, B

1996-02-01

375

Porphyromonas gingivalis Strain Variability and Periodontitis  

OpenAIRE

To determine if there is variability in virulence among strains of Porphyromonas gingivalis in human periodontitis, their distribution in a group of subjects with clear indicators of periodontitis and in a healthy, age-matched control group was examined. The presence of heteroduplex types of P. gingivalis in the two groups was determined with a PCR-based assay. This assay relied on detection of polymorphisms in the ribosomal internal spacer region (ISR). ISR fragments generated by PCR with P....

Griffen, Ann L.; Lyons, Sharon R.; Becker, Mitzi R.; Moeschberger, Melvin L.; Leys, Eugene J.

1999-01-01

376

The association of periodontitis and metabolic syndrome  

OpenAIRE

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 ...

Gurav, Abhijit N.

2014-01-01

377

Effect of gene polymorphisms on periodontal diseases  

OpenAIRE

Periodontal diseases are inflammatory diseases of supporting structures of the tooth. It results in the destruction of the supporting structures and most of the destructive processes involved are host derived. The processes leading to destruction and regeneration of the destroyed tissues are of great interest to both researchers and clinicians. The selective susceptibility of subjects for periodontitis has remained an enigma and wide varieties of risk factors have been implicated for the mani...

Tarannum, Fouzia; Faizuddin, Mohamed

2012-01-01

378

Quorum Sensing Inhibition, Relevance to Periodontics  

Science.gov (United States)

Quorum sensing helps bacteria to communicate with each other and in coordinating their behavior. Many diseases of human beings, plants, and animals are mediated by quorum sensing. Various approaches are being tried to inhibit this communication to control the diseases caused by bacteria. Periodontal pathogens also communicate through quorum sensing and new approaches to treat periodontal disease using quorum sensing inhibition need to explored. PMID:25709373

Yada, Sudheer; Kamalesh, B; Sonwane, Siddharth; Guptha, Indra; Swetha, R K

2015-01-01

379

Diabetes, periodontitis, and the subgingival microbiota  

OpenAIRE

Both type 1 and type 2 diabetes have been associated with increased severity of periodontal disease for many years. More recently, the impact of periodontal disease on glycaemic control has been investigated. The role of the oral microbiota in this two-way relationship is at this stage unknown. Further studies, of a longitudinal nature and investigating a wider array of bacterial species, are required in order to conclusively determine if there is a difference in the oral microbiota of diabet...

Ohlrich, Edward J.; Cullinan, Mary P.; Leichter, Jonathan W.

2010-01-01

380

Periodontitis in patients with focal tuberculosis  

Directory of Open Access Journals (Sweden)

Full Text Available The research goal is to investigate the mechanisms of formation and peculiarities of periodontitis in patients with focal tuberculosis. Patients with periodontitis and focal tuberculosis are proved to develop local inflammatory reaction with increased infection and activation of proinflammatory cytokines in parodontal pockets fluid. The main risk factor of frequent and durable recurrence of parodontal pathology in case of focal tuberculosis was the development of pathologic process as a cause of disbalance of lipid peroxidation and antioxidant system, endotoxicosis syndrome

Alexandrova ?.?.

2010-12-01

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