Minimally-invasive dentistry via dual-function novel bioactive low-shrinkage-stress flowable nanocomposites.

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.

Long-term antibacterial activity and cytocompatibility of novel low-shrinkage-stress, remineralizing composites.

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).

Low-shrinkage-stress nanocomposite: An insight into shrinkage stress, antibacterial, and ion release properties.

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.

Bioactive low-shrinkage-stress nanocomposite suppresses S. mutans biofilm and preserves tooth dentin hardness.

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.

Novel pit and fissure sealant containing nano-CaF and dimethylaminohexadecyl methacrylate with double benefits of fluoride release and antibacterial function.

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.

Novel low-shrinkage-stress nanocomposite with remineralization and antibacterial abilities to protect marginal enamel under biofilm.

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.

High-Performance Dental Adhesives Containing an Ether-Based Monomer.

Dental adhesives are vital for the success of dental restorations. The objective of this study is to make strong and durable dental adhesives that are free from 2 symbolic methacrylate-based dental resins-2-bis[4-(2-hydroxy-3-methacryl-oxypropoxy)-phenyl]-propane (Bis-GMA) and 2-hydroxyethyl-methacrylate (HEMA)-and have equivalent/improved bonding strength and durability. We formulated, prepared, and evaluated 2 dental adhesives using mixtures of a hydrolytically stable ether-based monomer, triethylene glycol divinylbenzyl ether (TEG-DVBE), with urethane dimethacrylate (UDMA) or pyromellitic glycerol dimethacrylate.

In Vitro Models, Standards, and Experimental Methods for Tobacco Products.

Traditional tobacco products have well-known systemic and local oral effects, including inflammation, vasoconstriction, delayed wound healing, and increased severity of periodontal disease. Specifically in the oral cavity and the lung, cigarette smoking produces cancer, increased infectivity, acute and chronic inflammation, changes in gene expression in epithelial lining cells, and microbiome changes. In recent years, cigarette smoking has greatly decreased in the United States, but the use of new tobacco products has gained tremendous popularity.

Iron oxide nanoparticle-calcium phosphate cement enhanced the osteogenic activities of stem cells through WNT/β-catenin signaling.

Calcium phosphate cement (CPC), functionalized with iron oxide nanoparticles (IONP), is of great promise to promote osteoinduction and new bone formation. In this work, the IONP powder was added into the CPC powder to fabricate CPC + IONP scaffolds and the effects of the novel composite on bone matrix formation and osteogenesis of human dental pulp stem cells (hDPSCs) were explored. A series of CPC + IONP magnetic scaffolds with different IONP contents (1%, 3% and 6%) were fabricated using 5% chitosan solution as the cement liquid.

Novel root canal sealer with dimethylaminohexadecyl methacrylate, nano-silver and nano-calcium phosphate to kill bacteria inside root dentin and increase dentin hardness.

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.

Stoichiometry and Kinetics of Sequential Dimethacrylate Enzymolysis.

The increasing use of methacrylate-based materials in tissue engineering and dental restorations demands detailed evaluation of enzymolysis of these materials due to toxicity, durability, and biocompatibility concerns. The objective of this study is to develop tools for assessing and ranking the enzymolysis kinetics of dimethacrylate (DMA) compounds. Triethyleneglycol DMA and diurethane DMA are employed as model DMAs for kinetic studies of 2-step enzymolysis by 2 esterases, pseudocholine esterase and cholesterol esterase.

Morphological and kinetic study of oral keratinocytes assembly on reconstituted basement membrane: Effect of TEGDMA.

Objective: Open wounds of oral cavity require rapid healing. The cytotoxic monomer, triethylene glycol dimethacrylate (TEGDMA) can leach out from dental restoratives, reach the oral epithelial barrier and trigger an immune response. It is speculated that low and moderate concentrations of TEGDMA (0.

Self-healing adhesive with antibacterial activity in water-aging for 12 months.

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).

Synthesis, Purification and Characterization of Polymerizable Multifunctional Quaternary Ammonium Compounds.

Methacrylate analogs of quaternary ammonium salts functionalized with carboxylic (AMadh1 68.8% yield, AMadh2 53.2% yield) and methoxysilane (AMsil1 94.

Ionic Dimethacrylates for Antimicrobial and Remineralizing Dental Composites.

Two ionic dimethacrylates (IDMA1 and IDMA2) intended for utilization in multifunctional, antibacterial and remineralizing dental resins and composites were synthesized by nucleophilic substitution reactions. Crude IDMAs were purified by multi-step extraction from ethanol-diethyl ether-hexane solvent system. Their structures were validated by nuclear magnetic resonance and mass spectrometry.

A possible risk of CAD/CAM-produced composite resin premolar crowns on a removable partial denture abutment tooth: a 3-year retrospective cohort study.

Purpose: To evaluate the early performance of computer-aided design/computer-aided manufacturing (CAD/CAM)-produced composite resin crown (CAD/CAM composite crown) treatment on premolars, specifically, placement on a removable partial denture (RPD) abutment tooth, and the distalmost tooth in the dental arch, as possible clinical risk factors.

Methods: A retrospective cohort study (April 2014 to July 2017) was performed utilizing the clinical records of patients who received a premolar CAD/CAM composite crown treatment. The variables of time of treatment for (1) successful crowns (complication event-free) and (2) surviving crowns (clinically functional including re-luted) were estimated using Kaplan-Meier analysis.

A thick frame decreases the fracture toughness of veneering ceramics used for zirconia-based all-ceramic restorations.

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.

Miniature specimens for fracture toughness evaluation of dental resin composites.

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.

Novel rechargeable calcium phosphate nanoparticle-filled dental cement.

The objectives were to develop a novel rechargeable cement containing amorphous calcium-phosphate nanoparticles (nanoACP) to suppress tooth decay. Five cements were made with: (1) 60% glass particles (experimental control); (2) 40% glass+20% nanoACP; (3) 30% glass+30% nanoACP; (4) 20% glass+40% nanoACP; (5) 10% glass+50% nanoACP. Groups 1-4 had enamel bond strengths similar to Transbond XT (3M) and Vitremer (3M) (p>0.

Stoichiometric analysis of competing intermolecular hydrogen bonds using infrared spectroscopy.

We quantitatively analyze multiple hydrogen bonds in mixtures of two monomers: urethane dimethacrylate (UDMA) and triethylene glycol-divinylbenzyl ether (TEG-DVBE). The carbonyl stretching band in infrared (IR) absorption spectra is deconvoluted into free and hydrogen-bonded carbonyl groups. The amounts of the sub-components are determined for 21 mixture compositions and initially analyzed using a simple stoichiometric model (based on one dominant hydrogen acceptor group per monomer species) for the equilibrium state of hydrogen bond formation.

Oral mucosa-on-a-chip to assess layer-specific responses to bacteria and dental materials.

The human oral mucosa hosts a diverse microbiome and is exposed to potentially toxic biomaterials from dental restoratives. Mucosal health is partly determined by cell and tissue responses to challenges such as dental materials and pathogenic bacteria. An model to rapidly determine potential layer-specific responses would lead to a better understanding of mucosal homeostasis and pathology.

Durability of self-healing dental composites: A comparison of performance under monotonic and cyclic loading.

Unlabelled: Durability is an important quality of dental restorative materials, and the ability to autonomously heal damage incurred during their oral function is highly desirable.

Objective: The objective was to evaluate the improvement in durability of self-healing dental composites (SHDCs) in terms of their resistance to fracture and capacity for healing of damage under monotonic and cyclic loading.

Methods: SHDCs were prepared by incorporating dental resin composites with microcapsules containing healing liquid.

Protein-repellent nanocomposite with rechargeable calcium and phosphate for long-term ion release.

Objective: There has been no report on the effect of incorporating protein repellent 2-methacryloyloxyethyl phosphorylcholine (MPC) into a composite containing nanoparticles of amorphous calcium phosphate (NACP) on calcium (Ca) and phosphate (P) ion rechargeability. The objectives of this study were to develop a Ca and P ion-rechargeable and protein-repellent composite for the first time, and investigate the effects of MPC and NACP on mechanical properties, protein-repellency, anti-biofilm effects, and Ca and P ion recharge and re-release.

Methods: NACP were synthesized using a spray-drying technique.

Assessing the effect of triethyleneglycol dimethacrylate on tissue repair in 3D organotypic cultures.

Leachables from dental restoratives induce toxicity in gingival and pulp tissues and affect tissue regeneration/healing. Appropriate testing of these materials requires a platform that mimics the in vivo environment and allows the architectural self-assembly of cells into tissue constructs. In this study, we employ a new 3D model to assess the impact of triethyleneglycol dimethacrylate (TEGDMA) on early organization and advanced recruitment/accumulation of immortalized mouse gingival fibroblasts (GFs) and dental papilla mesenchymal cells (DPMCs) in extracellular matrix.