Complement C5a Implication in Axonal Growth After Injury.

Complement C5a protein has been shown to play a major role in tissue regeneration through interaction with its receptor (C5aR) on target cells. Expression of this receptor has been reported in the nervous system which, upon injury, has no treatment to restore the lost functions. This work aimed at investigating the Complement C5a effect on axonal growth after axotomy in vitro.

Tissue-Engineered Oral Epithelium for Dental Material Testing: Toward Biomimetic Models.

Tissue-engineered oral epithelium (ΤΕΟΕ) was developed after comparing various culture conditions, including submerged (SUB) and air-liquid interface (ALI) human cell expansion options. Barrier formation was evaluated via transepithelial electrical resistance (TEER) and calcein permeation via spectrofluorometry. TEOE was further assessed for long-term viability via live/dead staining and development of intercellular connections via transmission electron microscopy.

Immunological isolation and characterization of neuronal progenitors from human dental pulp: A laboratory-based investigation.

Aims: Dental pulp stem cells (DPSCs) contain a population of stem cells with a broad range of differentiation potentials, as well as more lineage-committed progenitors. Such heterogeneity is a significant obstacle to experimental and clinical applications. The aim of this study is to isolate and characterize a homogenous neuronal progenitor cell population from human DPSCs.

The Added Value of a Collagenated Thermosensitive Bone Substitute as a Scaffold for Bone Regeneration.

A pre-hydrated thermosensitive collagenated biomaterial which sets at body temperature and maintains the space of the missing alveolar bone volume, OsteoBiol GTO (GTO), has been released as a bone substitute. This study was designed to check its angiogenic and osteogenic potentials compared to OsteoBiol Gen-Os (Gen-Os) and Geistlich Bio-Oss (Bio-Oss). Samples of materials were incubated in culture media to obtain the extracts.

Osteogenic Potential of a Polyethylene Glycol Hydrogel Functionalized with Poly-Lysine Dendrigrafts (DGL) for Bone Regeneration.

Resorbable hydrogels are widely used as scaffolds for tissue engineering. These hydrogels can be modified by grafting dendrimer-linked functionalized molecules (dendrigrafts). Our aim was to develop a tunable poly(L-lysine) dendrigrafts (DGL)/PEG-based hydrogel with an inverse porosity and to investigate its osteogenic potential.

Regulation of caries-induced pulp inflammation by NLRP3 inflammasome: A laboratory-based investigation.

Aim: To evaluate the expression and function of the nod-like receptor pyrin domain containing 3 (NLRP3) inflammasome in caries induced pulpitis.

Methodology: NLRP3 expression was determined with immunohistochemistry in the dental pulp and qPCR in dental pulp cells (DPCs). THP-1 macrophages expressing the apoptosis-related speck-like protein (ASC) and green fluorescent protein (GFP) fusion protein were used to assess NLRP3 inflammasome activation by live cell imaging, following treatment with lipopolysaccharide (LPS) and lipoteichoic acid (LTA).

Novel Antibacterial Properties of the Human Dental Pulp Multipotent Mesenchymal Stromal Cell Secretome.

It is well recognized that clearance of bacterial infection within the dental pulp precedes pulpal regeneration. However, although the regenerative potential of the human dental pulp has been investigated extensively, its antimicrobial potential remains to be examined in detail. In the current study bactericidal assays were used to demonstrate that the secretome of dental pulp multipotent mesenchymal stromal cells (MSCs) has direct antibacterial activity against the archetypal Gram-positive and Gram-negative bacteria, Staphylococcus aureus and Escherichia coli, respectively, as well as the oral pathogens Streptococcus mutans, Lactobacillus acidophilus, and Fusobacterium nucleatum.

Nanoarchitectonics of Electrically Activable Phosphonium Self-Assembled Monolayers to Efficiently Kill and Tackle Bacterial Infections on Demand.

Prosthetic implants are widely used in dentistry and orthopedics and, as a result, infections can occur which cause their removal. Therefore, it is essential to propose methods of eradicating the bacteria that remain on the prosthesis during treatment. For this purpose, it is necessary to develop surfaces whose antibacterial activity can be controlled.

Multicomponent Peptide Hydrogels as an Innovative Platform for Cell-Based Tissue Engineering in the Dental Pulp.

In light of the increasing levels of antibiotic resistance, nanomaterials and novel biologics are urgently required to manage bacterial infections. To date, commercially available self-assembling peptide hydrogels have not been studied extensively for their ability to inhibit micro-organisms relevant to tissue engineering sites such as dental root canals. In this work, we assess the biocompatibility of dental pulp stem/stromal cells with commercially available multicomponent peptide hydrogels.

Fibroblasts Control Macrophage Differentiation during Pulp Inflammation.

Introduction: During pulp inflammation, recruited macrophages can differentiate into 2 phenotypes: proinflammatory M1 and anti-inflammatory M2. Pulp fibroblasts have previously been shown to regulate pulp inflammation via cytokine and growth factor secretion. We hypothesized that upon carious injury, pulp fibroblasts interact with macrophages and modulate their differentiation.

Identification and validation of novel biomarkers and therapeutics for pulpitis using connectivity mapping.

Aim: To create an irreversible pulpitis gene signature from microarray data of healthy and inflamed dental pulps, followed by a bioinformatics approach using connectivity mapping to identify therapeutic compounds that could potentially treat pulpitis.

Methodology: The Gene Expression Omnibus (GEO) database, an international public repository of genomics data sets, was searched for human microarray datasets assessing pulpitis. An irreversible pulpitis gene expression signature was generated by differential expression analysis.

Ultrashort Peptide Hydrogels Display Antimicrobial Activity and Enhance Angiogenic Growth Factor Release by Dental Pulp Stem/Stromal Cells.

Recent studies on peptide hydrogels have shown that ultrashort peptides (<8 amino acids) can self-assemble into hydrogels. Ultrashort peptides can be designed to incorporate antimicrobial motifs, such as positively charged lysine residues, so that the peptides have inherent antimicrobial characteristics. Antimicrobial hydrogels represent a step change in tissue engineering and merit further investigation, particularly in applications where microbial infection could compromise healing.

Endogenous Mas-related G-protein-coupled receptor X1 activates and sensitizes TRPA1 in a human model of peripheral nerves.

Mas-related G-protein-coupled receptor X1 (MrgprX1) is a human-specific Mrgpr and its expression is restricted to primary sensory neurons. However, its role in nociception and pain signaling pathways is largely unknown. This study aims to investigate a role for MrgprX1 in nociception via interaction with the pain receptor, Transient Receptor Potential Ankyrin 1 (TRPA1), using in-vitro and in-vivo human neuronal models.

Biocompatibility assessment of resin-based cements on vascularized dentin/pulp tissue-engineered analogues.

Objectives: A three-dimensional (3D) dentin/pulp tissue analogue, resembling the human natural tissue has been engineered in an in vitro setup, aiming to assess the cytocompatibility of resin-based dental restorative cements.

Methods: Stem Cells from Apical Papilla (SCAP) and Human Umbilical Vein Endothelial Cells (HUVEC) were embedded in Collagen-I/Fibrin hydrogels at 1:3 ratio within 24-well plates. Hanging culture inserts were placed over the hydrogels, housing an odontoblast-like cell layer and a human treated-dentin barrier.

Advanced in Vitro Experimental Models for Tissue Engineering-based Reconstruction of a 3D Dentin/pulp Complex: a Literature Review.

Objective: Experimental procedures have been used to monitor cellular responses at the dentin/pulp interface. Aiming to divert from in vivo studies and oversimplified two-dimensional assays, three-dimensional (3D) models have been developed. This review provides an overview of existing literature, regarding 3D in vitro dentin/pulp reconstruction.

Complement activation links inflammation to dental tissue regeneration.

Objectives: Complement is an efficient plasma immune surveillance system. It initiates inflammation by inducing vascular modifications and attracting immune cells expressing Complement receptors. Investigating Complement receptors in non-immune cells pointed out Complement implication in the regeneration of tissue such as liver, skin, or bone.

Conservative Management of Mature Permanent Teeth with Carious Pulp Exposure.

Vital pulp therapy (VPT) in mature permanent teeth with carious pulp exposure has been a matter of debate, with root canal therapy being the conventional standard of care. Previously reported negative outcomes for VPT in these teeth were based on data from studies that have used calcium hydroxide in direct pulp capping and partial and full pulpotomy. The introduction of hydraulic calcium silicate-based materials with sealing and bioactive potentials have opened a new era in VPT with more favorable results.

Pulp Fibroblast Contribution to the Local Control of Pulp Inflammation via Complement Activation.

Upon traumatic injuries or carious lesions, the elimination of bacteria infiltrating the pulp is recognized as a prerequisite for initiating the regeneration process. Complement is a major system involved in initiating the inflammatory reaction and the subsequent bacteria elimination. This plasma system of above 35 proteins is synthesized by the liver and some immune cells.

Preclinical effectiveness of an experimental tricalcium silicate cement on pulpal repair.

Objectives: To investigate the pulpal repair potential of an experimental zirconium-oxide containing tricalcium-silicate cement, referred to as 'TCS 50'.

Materials And Methods: The effect of TCS 50 on viability, proliferation, migration, and odontoblastic differentiation of human dental pulp cells (HDPCs) was assessed using XTT assay, in-vitro wound healing assay and RT-PCR, respectively. Additionally, the pulp-capping potential was evaluated using a vital human tooth model.

Xenogeneic bone filling materials modulate mesenchymal stem cell recruitment: role of the Complement C5a.

Objectives: When bone filling materials are applied onto the periodontal tissues in vivo, they interact with the injured periodontal ligament (PDL) tissue and modulate its activity. This may lead to mesenchymal stem cells (MSCs) recruitment from bone marrow and initiate bone regeneration. Our hypothesis is that the filling materials affect PDL cells and MSCs functional activities by modulating PDL C5a secretion and subsequent MSCs proliferation and recruitment.

The consequence of substrates of large-scale rigidity on actin network tension in adherent cells.

There is compelling evidence that substrate stiffness affects cell adhesion as well as cytoskeleton organization and contractile activity. This work was designed to study the cytoskeletal contractile activity of single cells plated on micropost substrates of different stiffness using a numerical model simulating the intracellular tension of individual cells. We allowed cells to adhere onto micropost substrates of various rigidities and used experimental traction force data to infer cell contractility using a numerical model.

BioRoot RCS Extracts Modulate the Early Mechanisms of Periodontal Inflammation and Regeneration.

Introduction: The balance between periapical tissue inflammation and regeneration after the removal of necrotic/infected tissues is pivotal in determining the success of endodontic treatment. This study was designed to investigate the effect of silicate-based root canal sealer BioRoot RCS (BRCS; Septodont, Saint-Maur-des-Fossés, France) on modulating the inflammatory mechanisms and early steps of regeneration initiated by human periodontal ligament (PDL) fibroblasts.

Methods: Samples of BRCS and Pulp Canal Sealer (PCS; SybronEndo, Orange, CA) were incubated in culture medium to obtain material extracts.

Survival of human dental pulp cells after 4-week culture in human tooth model.

Objectives: This study aimed to validate the human tooth model by investigating the growth efficiency, expression of mesenchymal stem cell (MSC) markers and differentiation ability of human dental pulp cells (hDPCs) harvested from extracted immature third molars and cultured for different periods. Moreover, the effect of exposure and capping with a hydraulic calcium-silicate cement on pulp tissue after 4-week culture in the tooth model was investigated.

Methods: Primary hDPCs were collected from 18 molars from six individuals (15-19 years).

Investigating unset endodontic sealers' eugenol and hydrocortisone roles in modulating the initial steps of inflammation.

Introduction: Endodontic treatment success is achieved not only when the cement provides a hermetic seal but also when the injured periapical tissue is regenerated. However, an exaggerated inflammatory reaction hinders tissue regeneration and it has been shown that dental materials affect the inflammatory response through modulation of cytokine secretion. This work was set to investigate the effects of the presence of hydrocortisone in zinc oxide eugenol sealers (Endomethasone N) on modulating the initial steps of inflammation in vitro.