Influence of Inflammation to Lymphangiogenesis in Human Dental Pulp

Summary During inflammation, lymphangiogenesis takes place to enhance the transport of filtered fluid, proteins, and immune cells. Dental pulp tissue is frequently exposed to inflammatory insults, but the lymphatic system of the pulp and its responses to injury have not been investigated in detail using specific lymphatic markers. The aim of this study was to evaluate and to compare the lymphatic system in health dental pulp and pulp with inflammation, and to establish whether lymphangiogenesis takes place during dental pulp inflammation. Ten pulps with irreversibile pulpitis and eleven samples of healthy dental pulps were included in this study. All pulp samples were analyzed microscopically using the standard hematoxylin-eosin (HE) staining to detect the presence of inflammation. Immunohistochemical staining was performed using monoclonal anti-CD31 antibody (DAKO) at dilution 1:20. Microvessels identified by CD31, in which lumen the red blood cells were not detected, were considered as lymph vessels. Active areas of lymphangiogenesis (“hot spots”) were selected using low magnification. Images from five high power fields in the hot spot areas were recorded for each sample. Lymph vessels were counted using ImageJ program. The total number of lymph vessels so obtained was then divided by the number of the counted hot spots, and the result was used to denote the lymph vessel density. The mean number of lymphatic vessels, detected by CD31, in the group without inflammation was significantly lower than in the group with inflammation (3.75 versus 13.58, t=7.093, p<0.001). The present study established an increased number of lymphatic vessels in the inflamed human dental pulp suggesting that inflammation contributes to lymphangiogenesis.

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Specialized pro-resolving lipid mediators in endodontics: a narrative review

BMC Oral Health ◽

10.1186/s12903-021-01619-8 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Davy Aubeux ◽

Ove A. Peters ◽

Sepanta Hosseinpour ◽

Solène Tessier ◽

Valérie Geoffroy ◽

...

Keyword(s):

Dental Pulp ◽

Tissue Injury ◽

Inflammatory Diseases ◽

Promising Result ◽

Young Patients ◽

Lipid Mediators ◽

Pulp Tissue ◽

Pulp Inflammation ◽

Wide Range ◽

Human Dental Pulp

AbstractEndodontics is the branch of dentistry concerned with the morphology, physiology, and pathology of the human dental pulp and periradicular tissues. Human dental pulp is a highly dynamic tissue equipped with a network of resident immunocompetent cells that play major roles in the defense against pathogens and during tissue injury. However, the efficiency of these mechanisms during dental pulp inflammation (pulpitis) varies due to anatomical and physiological restrictions. Uncontrolled, excessive, or unresolved inflammation can lead to pulp tissue necrosis and subsequent bone infections called apical periodontitis. In most cases, pulpitis treatment consists of total pulp removal. Although this strategy has a good success rate, this treatment has some drawbacks (lack of defense mechanisms, loss of healing capacities, incomplete formation of the root in young patients). In a sizeable number of clinical situations, the decision to perform pulp extirpation and endodontic treatment is justifiable by the lack of therapeutic tools that could otherwise limit the immune/inflammatory process. In the past few decades, many studies have demonstrated that the resolution of acute inflammation is necessary to avoid the development of chronic inflammation and to promote repair or regeneration. This active process is orchestrated by Specialized Pro-resolving lipid Mediators (SPMs), including lipoxins, resolvins, protectins and maresins. Interestingly, SPMs do not have direct anti-inflammatory effects by inhibiting or directly blocking this process but can actively reduce neutrophil infiltration into inflamed tissues, enhance efferocytosis and bacterial phagocytosis by monocytes and macrophages and simultaneously inhibit inflammatory cytokine production. Experimental clinical application of SPMs has shown promising result in a wide range of inflammatory diseases, such as renal fibrosis, cerebral ischemia, marginal periodontitis, and cancer; the potential of SPMs in endodontic therapy has recently been explored. In this review, our objective was to analyze the involvement and potential use of SPMs in endodontic therapies with an emphasis on SPM delivery systems to effectively administer SPMs into the dental pulp space.

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Resolvin E1 accelerates pulp repair by regulating inflammation and stimulating dentin regeneration in dental pulp stem cells

Stem Cell Research & Therapy ◽

10.1186/s13287-021-02141-y ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jie Chen ◽

Huaxing Xu ◽

Kun Xia ◽

Shuhua Cheng ◽

Qi Zhang

Keyword(s):

Dental Pulp ◽

Tissue Repair ◽

Pulp Tissue ◽

Tissue Repair And Regeneration ◽

Injury Model ◽

Tnf Α ◽

Pulp Inflammation ◽

Inflammation Resolution ◽

Pulp Repair ◽

Dentin Regeneration

Abstract Background Unresolved inflammation and tissue destruction are considered to underlie the failure of dental pulp repair. As key mediators of the injury response, dental pulp stem cells (DPSCs) play a critical role in pulp tissue repair and regeneration. Resolvin E1 (RvE1), a major dietary omega-3 polyunsaturated fatty-acid metabolite, is effective in resolving inflammation and activating wound healing. However, whether RvE1 facilitates injured pulp-tissue repair and regeneration through timely resolution of inflammation and rapid mobilization of DPSCs is unknown. Therefore, we established a pulp injury model and investigated the effects of RvE1 on DPSC-mediated inflammation resolution and injured pulp repair. Methods A pulp injury model was established using 8-week-old Sprague-Dawley rats. Animals were sacrificed on days 1, 3, 7, 14, 21, and 28 after pulp capping with a collagen sponge immersed in PBS with RvE1 or PBS. Hematoxylin-eosin and Masson’s trichrome staining, immunohistochemistry, and immunohistofluorescence were used to evaluate the prohealing properties of RvE1. hDPSCs were incubated with lipopolysaccharide (LPS) to induce an inflammatory response, and the expression of inflammatory factors after RvE1 application was measured. Effects of RvE1 on hDPSC proliferation, chemotaxis, and odontogenic differentiation were evaluated by CCK-8 assay, transwell assay, alkaline phosphatase (ALP) staining, alizarin red staining, and quantitative PCR, and possible signaling pathways were explored using western blotting. Results In vivo, RvE1 reduced the necrosis rate of damaged pulp and preserved more vital pulps, and promoted injured pulp repair and reparative dentin formation. Further, it enhanced dentin matrix protein 1 and dentin sialoprotein expression and accelerated pulp inflammation resolution by suppressing TNF-α and IL-1β expression. RvE1 enhanced the recruitment of CD146+ and CD105+ DPSCs to the damaged molar pulp mesenchyme. Isolated primary cells exhibited the mesenchymal stem cell immunophenotype and differentiation. RvE1 promoted hDPSC proliferation and chemotaxis. RvE1 significantly attenuated pro-inflammatory cytokine (TNF-α, IL-1β, and IL-6) release and enhanced ALP activity, nodule mineralization, and especially, expression of the odontogenesis-related genes DMP1, DSPP, and BSP in LPS-stimulated DPSCs. RvE1 regulated AKT, ERK, and rS6 phosphorylation in LPS-stimulated DPSCs. Conclusions RvE1 promotes pulp inflammation resolution and dentin regeneration and positively influences the proliferation, chemotaxis, and differentiation of LPS-stimulated hDPSCs. This response is, at least partially, dependent on AKT, ERK, and rS6-associated signaling in the inflammatory microenvironment. RvE1 has promising application potential in regenerative endodontics.

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NLRP6‐caspase 4 inflammasome activation in response to cariogenic bacterial lipoteichoic acid in human dental pulp inflammation

International Endodontic Journal ◽

10.1111/iej.13469 ◽

2020 ◽

Author(s):

X. Tian ◽

R. Li ◽

C. Liu ◽

F. Liu ◽

L.J. Yang ◽

...

Keyword(s):

Dental Pulp ◽

Lipoteichoic Acid ◽

Inflammasome Activation ◽

Pulp Inflammation ◽

Human Dental Pulp

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A comparison of four extraction methods for substance P, neurokinin A and calcitonin gene-related peptide from human dental pulp tissue

Archives of Oral Biology ◽

10.1016/s0003-9969(99)00102-8 ◽

1999 ◽

Vol 44 (12) ◽

pp. 999-1004 ◽

Cited By ~ 9

Author(s):

L. Awawdeh ◽

F.T. Lundy ◽

C. Shaw ◽

P-J. Lamey ◽

G.J. Linden ◽

...

Keyword(s):

Substance P ◽

Dental Pulp ◽

Extraction Methods ◽

Calcitonin Gene Related Peptide ◽

Neurokinin A ◽

Pulp Tissue ◽

Related Peptide ◽

Calcitonin Gene ◽

Dental Pulp Tissue ◽

Human Dental Pulp

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Review on the Lymphatic Vessels in the Dental Pulp

Biology ◽

10.3390/biology10121257 ◽

2021 ◽

Vol 10 (12) ◽

pp. 1257

Author(s):

Kamila Wiśniewska ◽

Zbigniew Rybak ◽

Maria Szymonowicz ◽

Piotr Kuropka ◽

Maciej Dobrzyński

Keyword(s):

Dental Pulp ◽

Lymphatic System ◽

Light And Electron Microscopy ◽

Fluid Pressure ◽

Lymphatic Vessels ◽

Main Role ◽

Reaction Products ◽

Dental Tissues ◽

Optical Electron ◽

Antigen Antibody

Despite many studies, opinions on the lymphatic system of the teeth are still incompatible. Studies using light and electron microscopy and directly using methods such as a radioisotope (radionuclide) scan and interstitial fluid pressure measurement reported incomplete results. Immunohistochemistry (IHC) plays the main role in investigating presence of the lymphatic system in dental tissues. This method uses labeled antibodies against antigens typical of lymphatic vessels. The use of appropriate staining enables the detection of antigen-antibody reaction products using a light (optical), electron or fluorescence microscope. However, these studies do not show the system of vessels, their histologic structure under physiological conditions and inflammation as well as the lymphangiogenesis process in the dental pulp. Unfortunately, there is a lack of studies associating the presence of lymphatic vessels in the dental pulp with local lymphatic nodes or large vessels outside the tooth. In the scientific and research environment, the evaluation of the lymphatic system of the teeth is problematic because it is quite difficult to clearly distinguish lymphatic vessels from small blood vessels. Despite many indications of the presence of lymphatic vessels in the pulp chamber, this problem remains open and needs further research.

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Flow cytometric analysis of human dental pulp tissue

Journal of Endodontics ◽

10.1016/s0099-2399(06)81607-9 ◽

1991 ◽

Vol 17 (2) ◽

pp. 49-53 ◽

Cited By ~ 17

Author(s):

Chutima Mangkornkarn ◽

James C. Steiner ◽

Roger Bohman ◽

Robert A. Lindemann

Keyword(s):

Dental Pulp ◽

Flow Cytometric Analysis ◽

Pulp Tissue ◽

Flow Cytometric ◽

Dental Pulp Tissue ◽

Human Dental Pulp

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Human Dental Pulp Tissue during Orthodontic Tooth Movement: An Immunofluorescence Study

Journal of Functional Morphology and Kinesiology ◽

10.3390/jfmk5030065 ◽

2020 ◽

Vol 5 (3) ◽

pp. 65 ◽

Cited By ~ 1

Author(s):

Giovanna Vermiglio ◽

Antonio Centofanti ◽

Giovanni Matarese ◽

Angela Militi ◽

Marco Matarese ◽

...

Keyword(s):

Protein Expression ◽

Dental Pulp ◽

Tooth Movement ◽

Orthodontic Tooth Movement ◽

Control Group ◽

Pulp Tissue ◽

Force Application ◽

Dental Pulp Tissue ◽

Human Dental Pulp

The orthodontic tooth movement is the last step of several biological processes that take place after the application of external forces. During this process, dental pulp tissue is subjected to structural and protein expression modifications in order to maintain their integrity and functional morphology. The purpose of the present work was to perform an in vivo study, evaluating protein expression modifications in the human dental pulp of patients that have undergone orthodontic tooth movement due to pre-calibrated light force application for 30 days. Dental pulp samples were extracted from molars and premolars of the control group and after 7 and 30 days of treatment; the samples were then processed for immunofluorescence reactions using antibodies against fibronectin, collagen I and vascular endothelial growth factor (VEGF). Our results show that, after 7 days of treatment, all tested proteins change their pattern expression and will reset after 30 days. These data demonstrate that the dental pulp does not involve any irreversible iatrogenic alterations, supporting the efficacy and safety of using pre-calibrated force application to induce orthodontic tooth movement in clinical practice.

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Does hypersensitive teeth show pulp inflammation?

RGO - Revista Gaúcha de Odontologia ◽

10.1590/1981-86372019000113580 ◽

2019 ◽

Vol 67 ◽

Author(s):

Daniele Paraguassú FAGUNDES-DE-SOUZA ◽

Marcelo Henrique NAPIMOGA ◽

Andresa Borges SOARES ◽

Vera Cavalcanti ARAÚJO ◽

Cecilia Pedroso TURSSI

Keyword(s):

Inflammatory Response ◽

Dental Pulp ◽

Mineral Water ◽

Sagittal Plane ◽

Soft Drink ◽

Histological Evaluation ◽

Dentin Hypersensitivity ◽

Pulp Tissue ◽

Pulp Inflammation ◽

Significant Difference

ABSTRACT Objective: This study investigated the presence of inflammatory response in the dental pulp of rats showing hypersensitive dentin, induced by erosive episodes. Methods: Sixteen Wistar rats were fed with commercial sucrose-free pellet diet for 12 hours; whereas the food was removed during the remainder of the day, and the animals received mineral water or a lemon-based sucrose-free soft drink, according to the group to which they belonged. Eight animals consumed the soft drink to induce hypersensitivity, while the other 8 animals received mineral water (control). After six weeks, the animals were euthanized, the mandible was removed and subjected to a median incision in the sagittal plane, to obtain right and left hemimandibles. The slides stained with hematoxylin-eosin were analyzed using light microscopy. Results: Histological evaluation of the control and experimental groups revealed no inflammatory process in the pulp tissue, and the presence of inflammatory cells, such as lymphocytes, plasma cells, eosinophils and macrophages, was not observed. In addition, there was no edema or dilated and congested blood vessels. The Mann-Whitney test showed no significant difference (p = 1.000) between the experimental and the control groups. Conclusion: In the animal model used, dentin hypersensitivity does not trigger dental pulp inflammatory response.

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