Prrx2, the paired-related homeobox transcription factor, functions as a potential regulator of pannexin 3 expression in odontoblast differentiation.

Objectives: This study aimed to elucidate the roles of Prrx1 and Prrx2, homeobox transcription factors, in tooth development and determine whether Prrx2 regulates pannexin 3 (Panx3) expression, which is important in preodontoblasts.

Methods: Tooth sections were prepared from 13.5-, 15.

Impact of restorative material on fracture behaviors of class II restoration in endodontically treated deciduous molars.

The purpose of this study was to investigate the fracture behavior of endodontically treated (ET) deciduous molar when directly restored with different restorative materials in Class II (MO) cavities in comparison with permanent teeth. MO cavities were prepared with 2.4-2.

Gene-Transferred Skeletal Muscles with Needle-Type Electrodes as Efficient and Reliable Biomaterials for Bone Regeneration.

Background: Bone morphogenetic protein-2 () has a high potential to induce bone tissue formation in skeletal muscles. We developed a bone induction system in skeletal muscles using the gene through in vivo electroporation. Natural bone tissues with skeletal muscles can be considered potential candidates for biomaterials.

Effect of ethylene oxide unit number in bis-EMA on the physical properties of additive-manufactured occlusal splint material.

Purpose: To investigate the effects of the number of ethylene oxide units in bis-EMA on the physical properties of additively manufactured occlusal splints.

Methods: Seven experimental materials containing bis-EMAs with three and 10 ethylene oxide units (BE3 and BE10, respectively) were prepared at different BE10 content rates (BE10-0%, -20%, -30%, -40%, -50%, -60%, and -80%). Half the specimens of each material were aged in boiling water.

C-terminus of PIEZO1 governs Ca influx and intracellular ERK1/2 signaling pathway in mechanotransduction.

Cells sense and respond to extracellular mechanical stress through mechanotransduction receptors and ion channels, which regulate cellular behaviors such as cell proliferation and differentiation. Among them, PIEZO1, piezo-type mechanosensitive ion channel component 1, has recently been highlighted as a mechanosensitive ion channel in various cell types including mesenchymal stem cells. We previously reported that PIEZO1 is essential for ERK1/2 phosphorylation and osteoblast differentiation in bone marrow-derived mesenchymal stem cells (BMSCs), induced by hydrostatic pressure loading and treatment with the PIEZO1-specific activator Yoda1.

Effect of splinting material type and location on resistance against deflection force of splinted periodontally compromised teeth with hypermobility.

This study aimed to evaluate the effect of splinting material type and material location on the force resistance of splinted periodontally compromised teeth with hypermobility. Extracted teeth including the target tooth (maxillary second premolar) and its adjacent teeth were placed into the alveolar sockets of a dental arch model via artificial periodontal ligaments made of elastic impression material. Three different experimental models with varied target tooth mobility including Periotest® values (PTVs) of 20, 30, and 40 were fabricated (named models #20, #30, and #40, respectively).

Effect of 3D printing system and post-curing atmosphere on micro- and nano-wear of additive-manufactured occlusal splint materials.

Although additive manufacturing has been widely applied for occlusal splint (OS) fabrication, it is still unclear whether 3D printing system and post-curing atmosphere would play a role in the wear resistance of additive-manufactured OS. Therefore, the aim of this study was to evaluate the effect of 3D printing system (liquid crystal display (LCD) and digital light processing (DLP)) and post-curing atmosphere (air and nitrogen gas (N)) on the wear resistance of hard and soft OS materials for additive-manufactured OSs (KeySplint® Hard and Soft). The evaluated properties were microwear (by two-body wear test) and nano-wear resistances (by nanoindentation wear test) as well as flexural strength and flexural modulus (by three-point bending test), surface microhardness (by Vickers hardness test), and nanoscale elastic modulus (reduced elastic modulus) and nano surface hardness (by nanoindentation test).

Identification of GPI-anchored protein LYPD1 as an essential factor for odontoblast differentiation in tooth development.

Lipid rafts are membrane microdomains rich in cholesterol, sphingolipids, glycosylphosphatidylinositol-anchored proteins (GPI-APs), and receptors. These lipid raft components are localized at the plasma membrane and are essential for signal transmission and organogenesis. However, few reports have been published on the specific effects of lipid rafts on tooth development.

Deficiency of G protein-coupled receptor Gpr111/Adgrf2 causes enamel hypomineralization in mice by alteration of the expression of kallikrein-related peptidase 4 (Klk4) during pH cycling process.

Enamel is formed by the repetitive secretion of a tooth-specific extracellular matrix and its decomposition. Calcification of the enamel matrix via hydroxyapatite (HAP) maturation requires pH cycling to be tightly regulated through the neutralization of protons released during HAP synthesis. We found that Gpr115, which responds to changes in extracellular pH, plays an important role in enamel formation.

Development of a novel ex vivo organ culture system to improve preservation methods of regenerative tissues.

Recent advances in regenerative technology have made the regeneration of various organs using pluripotent stem cells possible. However, a simpler screening method for evaluating regenerated organs is required to apply this technology to clinical regenerative medicine in the future. We have developed a simple evaluation method using a mouse tooth germ culture model of organs formed by epithelial-mesenchymal interactions.

Therapeutic benefits of factors derived from stem cells from human exfoliated deciduous teeth for radiation-induced mouse xerostomia.

Radiation therapy for head and neck cancers is frequently associated with adverse effects on the surrounding normal tissue. Irreversible damage to radiation-sensitive acinar cells in the salivary gland (SG) causes severe radiation-induced xerostomia (RIX). Currently, there are no effective drugs for treating RIX.

Iroquois homeobox 3 regulates odontoblast proliferation and differentiation mediated by Wnt5a expression.

Iroquois homeobox (Irx) genes are TALE-class homeobox genes that are evolutionarily conserved across species and have multiple critical cellular functions in fundamental tissue development processes. Previous studies have shown that Irxs genes are expressed during tooth development. However, the precise roles of genes in teeth remain unclear.

Effect of Surface Polishing on Physical Properties of an Occlusal Splint Material for Additive Manufacturing under Protection Gas Post-Curing Condition.

The aim of this study was to evaluate the effect of surface polishing as well as the post-curing atmospheres (air and nitrogen gas) on the physical properties of an occlusal splint material for additive manufacturing. Flexural strength, flexural modulus, Vickers hardness number (VHN), degree of carbon double bond conversion (DC), water sorption (W), and water solubility (W) were evaluated. Surface polishing significantly affected the evaluated properties.

Three-dimensional microscopic comparison of wear behavior between immature and mature enamel: an in vitro study.

Background: Dental enamel, the hardest outermost layer of a human tooth, is subjected to occlusal forces throughout life during different oral function as talking, mastication etc. Due to this continuous stress, wear causes the loss of this protective shell. This study aimed to detect microscopic differences in enamel's wear behavior among different age groups of adolescents and adults.

Wear behavior of materials for additive manufacturing after simulated occlusion of deciduous dentition.

Objectives: To evaluate wear characteristics of materials for additive manufacturing (AM) after a simulated occlusal test in primary teeth. Wear was simulated by means of impacting - sliding wear testing (ISWT) between specimens prepared from materials for AM against enamel derived from deciduous teeth.

Methods: The prepared hemispherical upper specimens were subjected to impacting-sliding wear test (ISWT) machine against the flattened enamel of deciduous molars on lower specimens.

Effect of 3D Printer Type and Use of Protection Gas during Post-Curing on Some Physical Properties of Soft Occlusal Splint Material.

Despite the fact that three-dimensional (3D) printing is frequently used in the manufacturing of occlusal splints, the effects of the 3D printer type and post-curing methods are still unclear. The aim of this study was to investigate the effect of the printer type (digital light processing: DLP; and liquid crystal display: LCD) as well as the post-curing method with two different atmospheric conditions (air and nitrogen gas (N)) on the mechanical and surface properties of 3D-printed soft-type occlusal splint material. The evaluated properties were flexural strength, flexural modulus, Vickers hardness (VHN), fracture toughness, degree of double bond conversion (DC%), water sorption, water solubility, and 3D microlayer structure.

GSK3beta inhibitor-induced dental mesenchymal stem cells regulate ameloblast differentiation.

Objectives: Epithelial-mesenchymal interactions are extremely important in tooth development and essential for ameloblast differentiation, especially during tooth formation. We aimed to identify the type of mesenchymal cells important in ameloblast differentiation.

Methods: We used two types of cell culture systems with chambers and found that a subset of debtal mesenchimal cells is important for the differentiatiuon of dental spithelial cells into ameloblasts.

Effect of Nitrogen Gas Post-Curing and Printer Type on the Mechanical Properties of 3D-Printed Hard Occlusal Splint Material.

Although three-dimensional (3D) printing is clinically convenient to fabricate occlusal splints, it is still unclear how the post-curing method and the printer type can affect 3D-printed splints. This study aimed to evaluate the effect of stroboscopic post-curing at a nitrogen gas (N) atmosphere versus post-curing in an air atmosphere, as well as the printer type (liquid crystal display (LCD) and digital light processing (DLP)) on the mechanical properties of a 3D-printed hard-type occlusal splint material. Flexural strength, flexural modulus, Vickers hardness number (VHN), fracture toughness, degree of double bond conversion (DC), 3D microlayer structure, water sorption, and water solubility were evaluated.

Transient ventricular bigeminy during emergence from general anesthesia in a pediatric patient with catecholaminergic polymorphic ventricular tachycardia.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare genetic disease that is characterized by ventricular arrhythmias and sudden death, induced by exogenous and endogenous catecholamine. We performed general anesthesia for dental treatment of multiple teeth in a 7-year-old boy with CPVT. To avoid sympathetic tone, anesthesia was maintained by total intravenous anesthesia, but ventricular bigeminy was induced by stimulation on emergence form general anesthesia.

Conditioned Medium From the Stem Cells of Human Exfoliated Deciduous Teeth Ameliorates Neuropathic Pain in a Partial Sciatic Nerve Ligation Model.

In neuropathic pain (NP), injury or diseases of the somatosensory system often result in highly debilitating chronic pain. Currently, there is no effective drug for the complete and definitive treatment of NP. We investigated the therapeutic potential of conditioned medium (CM) derived from stem cells from human exfoliated deciduous teeth (SHED-CM) against NP using a mouse partial sciatic nerve ligation (PSL) model.

An ex vivo organ culture screening model revealed that low temperature conditions prevent side effects of anticancer drugs.

Development of chemotherapy has led to a high survival rate of cancer patients; however, the severe side effects of anticancer drugs, including organ hypoplasia, persist. To assume the side effect of anticancer drugs, we established a new ex vivo screening model and described a method for suppressing side effects. Cyclophosphamide (CPA) is a commonly used anticancer drug and causes severe side effects in developing organs with intensive proliferation, including the teeth and hair.

von Willebrand factor D and EGF domains regulate ameloblast differentiation and enamel formation.

Cell- and tissue-specific extracellular matrix (ECM) composition plays an important role in organ development, including teeth, by regulating cell behaviors, such as cell proliferation and differentiation. Here, we demonstrate for the first time that von Willebrand factor D and epidermal growth factor (EGF) domains (Vwde), a previously uncharacterized ECM protein, is specifically expressed in teeth and regulates cell proliferation and differentiation in inner enamel epithelial cells (IEEs) and enamel formation. We identified the Vwde as a novel ECM protein through bioinformatics using the NCBI expressed sequence tag database for mice.

Effects of pH on the Properties of Membrane Vesicles Including Glucosyltransferase in .

releases membrane vesicles (MVs) and induces MV-dependent biofilm formation. Glucosyltransferases (Gtfs) are bound to MVs and contribute to the adhesion and glucans-dependent biofilm formation of early adherent bacteria on the tooth surface. The biofilm formation of may be controlled depending on whether the initial pH tends to be acidic or alkaline.

Fibroblast growth factor 2 suppresses the expression of C-C motif chemokine 11 through the c-Jun N-terminal kinase pathway in human dental pulp-derived mesenchymal stem cells.

The regulation of the mesenchymal stem cell (MSC) programming mechanism promises great success in regenerative medicine. Tissue regeneration has been associated not only with the differentiation of MSCs, but also with the microenvironment of the stem cell niche that involves various cytokines and immune cells in the tissue regeneration site. In the present study, fibroblast growth factor 2 (FGF2), the principal growth factor for tooth development, dental pulp homeostasis and dentin repair, was reported to affect the expression of cytokines in human dental pulp-derived MSCs.

Connexin 43-Mediated Gap Junction Communication Regulates Ameloblast Differentiation ERK1/2 Phosphorylation.

Connexin 43 (Cx43) is an integral membrane protein that forms gap junction channels. These channels mediate intercellular transport and intracellular signaling to regulate organogenesis. The human disease oculodentodigital dysplasia (ODDD) is caused by mutations in Cx43 and is characterized by skeletal, ocular, and dental abnormalities including amelogenesis imperfecta.