Publications by authors named "Jirun Sun"

Root caries caused by cariogenic bacteria are a burden on a large number of individuals worldwide, especially the elderly. Applying a protective coating to exposed root surfaces has the potential to inhibit the development of caries, thus preserving natural teeth. This study aimed to develop a novel antibacterial coating to combat root caries and evaluate its effectiveness using the antibacterial monomer dimethylaminohexadecyl methacrylate (DMAHDM).

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Recurrent caries remain a persistent concern, often linked to microleakage and a lack of bioactivity in contemporary dental composites. Our study aims to address this issue by developing a low-shrinkage-stress nanocomposite with antibiofilm and remineralization capabilities, thus countering the progression of recurrent caries. In the present study, we formulated low-shrinkage-stress nanocomposites by combining triethylene glycol divinylbenzyl ether and urethane dimethacrylate, incorporating dimethylaminododecyl methacrylate (DMADDM), along with nanoparticles of calcium fluoride (nCaF) and nanoparticles of amorphous calcium phosphate (NACP).

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Objectives: Composites are commonly used for tooth restorations, but recurrent caries often lead to restoration failures due to polymerization shrinkage-stress-induced marginal leakage. The aims of this research were to: (1) develop novel low-shrinkage-stress (L.S.

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Objectives: Current dental resins exhibit polymerization shrinkage causing microleakage, which has the potential to cause recurrent caries. Our objectives were to create and characterize low-shrinkage-stress (LSS) composites with dimethylaminododecyl methacrylate (DMADDM) as an antibacterial agent to combat recurrent caries.

Methods: Triethylene glycol divinylbenzyl ether and urethane dimethacrylate were used to reduce shrinkage stress.

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Purpose: The purpose of this study was to investigate the reaction products formed by application of three tooth etchants to hydroxyapatite.

Methods: Tooth etchants with three different compositions, designed for application to teeth before dental adhesive - " K-etchant GEL" (containing phosphoric acid), "Enamel Conditioner" (containing organic acids), and "Multi Etchant" (containing acidic monomer) - were applied to hydroxyapatite plates.

Results: Atomic force microscopy measurements revealed that Multi Etchant formed nano-sized particles on the hydroxyapatite.

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Bioactive materials for dental resin restorations are a rising field of investigation exploring treatment strategies for reducing the recurrence of carious lesions. The current effort has been directed toward developing dental materials that can inhibit biofilms and prevent tooth mineral loss. Bioactive resin materials have shown the potential to interfere with polymicrobial consortia in vivo and help maintain the lifespan of restorations.

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This study reports two cases of squamous cell carcinoma of the thyroid (SCCT) presenting as the thyroid goiter, involving one case of primary squamous cell carcinoma originating from the thyroid (PSCCT) and the other case of secondary SCCT of the thyroid. A retrospective analysis of the clinical and pathological findings was done in this study report. In case 1, the thyroid ultrasound showed multi-hypoechoic well-defined nodules, labeled as 3 using Thyroid Imaging Reporting and Data System, measuring 34.

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The objective of this study is to replace a traditional methacrylate-based primer (glycine, N-(2-hydroxy-3-(2-methyl-1-oxo-2-propenyl)propyl)-N-(4-methylphenyl) monosodium salt, NTG-GMA) with a hydrolytically stable ether-based primer (glycine, N-2-hydroxy-3-(4-vinylbenzyloxy)-propyl-N-(4-methylphenyl), monosodium salt, NTG-VBGE). The performance and durability of bonding composites to detin of two primers combined with methacrylate-based or ether-based adhesives were evaluated using shear bond strength (SBS) and micro-tensile bond strength (μTBS) combined with thermal cycling. The hydrolysis resistance of NTG-VBGE against hydrolysis was tested by challenging primed hydroxyapatite crystals with an esterase.

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Objective: A low-shrinkage-stress resin-based cement with antibacterial properties could be beneficial to create a cement with lower stress at the tooth-restoration interface, which could help to enhance the longevity of the fixed dental restoration by reducing microleakage and recurrent caries. To date, there has been no report on the development of a low-shrinkage-stress and bio-interactive cement. Therefore, the objectives of this study were to develop a novel low-shrinkage-stress resin-based cement containing dimethylaminohexadecyl methacrylate (DMAHDM) and investigate the mechanical and antibacterial properties for the first time.

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Objectives: Recent studies developed low-shrinkage-stress composite with remineralizing and antibacterial properties to combat secondary caries and increase restoration longevity. However, their long-term durability in thermal cycling is unclear. The objectives of this study were to develop an antibacterial, remineralizing and low-shrinkage-stress composite, and to investigate its durability in thermal cycling for 20,000 cycles, equivalent to two years of clinical life.

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Background/purpose: A common reason for dental composite restoration failure is recurrent caries at the margins. Our objectives were to: (1) develop a novel low-shrinkage-stress, antibacterial and remineralizing resin composite; (2) evaluate the effects of dimethylaminohexadecyl methacrylate (DMAHDM) on mechanical properties, biofilm inhibition, calcium (Ca) and phosphate (P) ion release, degree of conversion, and shrinkage stress on the new low-shrinkage-stress resin composite for the first time.

Material And Methods: The resin consisted of urethane dimethacrylate (UDMA) and triethylene glycol divinylbenzyl ether (TEG-DVBE) with high resistance to salivary hydrolytic degradation.

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Dimethacrylate-based resin composites restorations have become widely-used intraoral materials in daily dental practice. The increasing use of composites has greatly enhanced modern preventive and conservative dentistry. They have many superior features, especially esthetic properties, bondability, and elimination of mercury and galvanic currents.

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Unlabelled: The objectives of this in vitro study were to develop a novel low-shrinkage-stress flowable nanocomposite with antibacterial properties through the incorporation of dimethylaminohexadecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP), and investigate the mechanical and oral biofilm properties, to be used in minimally-invasive techniques.

Methods: The light-cured low-shrinkage-stress flowable resin was formulated by mixing urethane dimethacrylate (UDMA) and triethylene glycol divinylbenzyl ether (TEG-DVBE) at a 1:1 mass ratio. Different mass fractions of glass, and either 5% DMAHDM or 20%NACP or both were incorporated.

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Objective: Composites with remineralizing and antibacterial properties are favorable for caries inhibition. The objectives of this study were to develop a new bioactive nanocomposite with remineralizing and antibiofilm properties by incorporating dimethylaminohexadecyl methacrylate (DMAHDM) and nano-calcium fluoride (nCaF).

Methods: nCaF was produced via a spray-drying method and integrated at 15% mass fraction into composite.

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A low-shrinkage-stress (LSS), antibacterial and remineralizing nanocomposite was recently developed; however, validation of its long-term antibacterial potency in modulating human salivary-derived biofilm is an unmet need. This study aimed to evaluate the antibacterial effect of the bioactive LSS composite before and after aging in acidic solution for 90 days using a multi-species biofilm model, and to evaluate its cytotoxicity. The LSS composite consisted of urethane dimethacrylate (UDMA) and triethylene glycol divinylbenzyl ether (TEG-DVBE), 3% dimethylaminohexadecyl methacrylate (DMAHDM) and 20% nanoparticles of amorphous calcium phosphate (NACP).

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The aims are: (a) To develop the first low-shrinkage-stress nanocomposite with antibacterial and remineralization capabilities through the incorporation of dimethylaminododecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP); (b) to investigate the effects of the new composite on biofilm inhibition, mechanical properties, shrinkage stress, and calcium (Ca) and phosphate (P) ion releases. The low-shrinkage-stress resin consisted of urethane dimethacrylate and triethylene glycol divinylbenzyl ether. Composite was formulated with 3% DMAHDM and 20% NACP.

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Recurrent dental caries is one of the main reasons for resin composite restoration failures. This study aimed to: (1) develop a bioactive, low-shrinkage-stress, antibacterial and remineralizing composite and evaluate the sustainability of its antibacterial effect against Streptococcus mutans (S. mutans) biofilms; and (2) evaluate the remineralization and cariostatic potential of the composite containing nanoparticles of amorphous calcium phosphate (NACP) and dimethylaminohexadecyl methacrylate (DMAHDM), using dentin hardness measurement and a biofilm-induced recurrent caries model.

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Objective: Pit and fissure sealants with antibacterial and remineralization properties have broad application prospects in caries prevention. The objectives of this study were to: (1) develop a novel pit and fissure sealant containing CaF nanoparticles (nCaF) and dimethylaminohexadecyl methacrylate (DMAHDM); and (2) investigate the effects of nCaF and DMAHDM on biofilm response and fluoride (F) ion release for the first time.

Methods: Helioseal F was used as a control.

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Objectives: Polymerization shrinkage stress may lead to marginal damage, microleakage and failure of composite restorations. The objectives of this study were to : (1) develop a novel nanocomposite with low-shrinkage-stress, antibacterial and remineralization properties to reduce marginal enamel demineralization under biofilms; (2) evaluate the mechanical properties of the composite and calcium (Ca) and phosphate (P) ion release; and (3) investigate the cytotoxicity of the new low-shrinkage-stress monomer in vitro.

Methods: The low-shrinkage-stress resin consisted of urethane dimethacrylate (UDMA) and triethylene glycol divinylbenzyl ether (TEG-DVBE), and 3 % dimethylaminohexadecyl methacrylate (DMAHDM) and 20 % calcium phosphate nanoparticles (NACP) were added.

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Objectives: Root canal re-infection and weakening of roots are two main challenges in endodontics. The objectives of the study were: (1) to develop a novel root canal sealer containing dimethylaminohexadecyl methacrylate (DMAHDM), nanoparticles of silver (NAg), and nanoparticles of amorphous calcium phosphate (NACP), and (2) to investigate the effects on the physical, anti-biofilm, remineralizing ions, and hardness of human dentin for the first time.

Methods: Methacrylate-resin dual-cured root canal sealer contained 5% DMAHDM, 0.

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Article Synopsis
  • Developed a new root canal sealer featuring dimethylaminohexadecyl methacrylate (DMAHDM) and silver nanoparticles (NAg) to combat endodontic treatment failures and biofilm recontamination.
  • Experimented with various concentrations of DMAHDM and NAg, assessing their impact on biofilm inhibition and the physical properties of the sealer.
  • Achieved significant reductions in biofilm formation and bacterial counts while maintaining effective sealing qualities compared to existing commercial sealers.
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Objective: Secondary caries and micro-cracks are the main limiting factors for dentin bond durability. The objectives of this study were to develop a self-healing adhesive containing dimethylaminohexadecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP), and investigate the effects of water-aging for 12 months on self-healing, dentin bonding, and antibacterial properties for the first time.

Methods: Microcapsules were synthesized with poly (urea-formaldehyde) (PUF) shells containing triethylene glycol dimethacrylate (TEGDMA) and N,N-dihydroxyethyl-p-toluidine (DHEPT).

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Purpose: To investigate the influence of firing condition and thickness of a yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) frame on the fracture toughness of veneering ceramics.

Methods: Layering and pressable ceramics without frames or on 0.8- and 1.

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Objective: Millimeter-scale ("miniature") specimens enable in-situ evaluation of mechanical properties of engineering materials at reduced cost. Here three such specimens for measuring fracture toughness (K) are developed and implemented to new dental materials. The latter include concurrent methacrylate-based and new ether-based resin composites designed to reduce polymerization stress and enhance service life in restored teeth.

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