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Glove Selection for Work with Acrylates Including Those Cured by Ultraviolet, Visible Light, or Electron Beam
Published in Robert N. Phalen, Howard I. Maibach, Protective Gloves for Occupational Use, 2023
Common UV or light-cured composites for dental fillings and sealants include bisphenol A-diglycidyl methacrylate (BIS-GMA), triethyleneglycol dimethacrylate (TREGDMA), 2-HEMA, TMPTA, and sometimes methyl methacrylate (MMA; Figure 23.2).66,67 The most common ACD reactions are to 2-HEMA and TREGDMA;62,65 however, reactions to 2-HPMA, THFMA, EMA, butanediol dimethacrylate (BUDMA), and urethane dimethacrylate (UDMA) are common among dental workers.62 In the latter, cross-allergy to other methacrylates is suspected.Methyl methacrylate (MMA).The figure shows the chemical structure for methyl methacrylate (MMA) with a carboxylic acid group (–COOH), bound to a carbon-carbon double bond (C=C), and bound to a methyl group (–CH3).
Effects of Thermal Cycling on Surface Hardness, Diametral Tensile Strength and Porosity of an Organically Modified Ceramic (ORMOCER)-Based Visible Light Cure Dental Restorative Resin
Published in P. Mereena Luke, K. R. Dhanya, Didier Rouxel, Nandakumar Kalarikkal, Sabu Thomas, Advanced Studies in Experimental and Clinical Medicine, 2021
Dental restorative polymer composite materials based on polymerizable bisphenol-A glycidyl methacrylate (Bis-GMA) monomers [1, 2] and quartz/radiopaque glass fillers has been the most popular materials used in dentistry, since Bowen [1, 2] introduced (Bis-GMA) in the 1960s. Though they have good aesthetic and physical properties [3], attempts including few structural variations in the organic matrix of dental composites are going on to improve the clinical performance of restorative materials [4–14]. Among these modifications, urethane dimethacrylates (UDMAs), [4] urethane tetramethacrylates, [5] organically modified ceramics (ORMOCERS) [6,-13], and bioactive materials [14] are included.
Interaction between microorganisms and dental material surfaces: general concepts and research progress
Published in Journal of Oral Microbiology, 2023
Yan Tu, Huaying Ren, Yiwen He, Jiaqi Ying, Yadong Chen
Resin composites have become the most common oral restorative materials [21] because of their widespread application in anterior and posterior teeth, unique aesthetic characteristics, and the advantage of easy handling. These materials are composed of a polymer matrix, reinforcing fillers, a silane coupling agent, and some chemical components that promote the regulation of the polymerization process. The main monomer in the composite resin is Bisphenol A-glycidyl methacrylate (bis-GMA), which is usually mixed with other dimethacrylates. In addition, the new monomer has a high molecular weight and can reduce the composite resin shrinkage. Resin composites are classified according to their fillers, especially concerning their size. The latest development in resin composites is the introduction of nanoparticle composite fillers, which can improve the mechanical and aesthetic properties of resin composites by reducing the particle size and bringing about even distribution [22]. Developing restorative materials that are not conducive to microbial adhesion and colonization is the goal of contemporary dental materials science. The development of new resin composites and adhesive systems prolongs the release of antibacterial agents [23–27]; however, biofilm formation also depends on the surface characteristics of these materials [28,29]. Therefore, fine-tuning the physical and chemical properties of resin composites can prevent biofilm formation, laying a solid foundation for developing new resins.
Tailoring the monomers to overcome the shortcomings of current dental resin composites – review
Published in Biomaterial Investigations in Dentistry, 2023
Jingwei He, Lippo Lassila, Sufyan Garoushi, Pekka Vallittu
Since being invented, Bis-GMA, which is a derivative of Bisphenol A (BPA), have dominated as the main monomer in DRCs. BPA is an endocrine-disrupting compound that can cause several diseases [157–161]. Although BPA is not a component of dental materials, and although alternative synthetic routes of Bis-GMA no longer require BPA, several studies still found the presence of BPA in patients’ urine and saliva after dental procedures [162]. Moreover, the latest studies showed that BPA may be released during the grinding and degradation of dental materials [163,164]. Consequently, numerous BPA-free monomers have been developed and used as alternatives to Bis-GMA, and most of them have shown promising properties and great potential in dentistry [74,146,165–177]. However, the estrogenicity of these new developed BPA-free monomers has not been investigated. Jun et al. [178] used isosorbide to synthesize light polymerizable isosorbide-derived biomonomers (ISDBs, as shown in Figure 19) and prepared Bis-GMA free sealants with ISDBs. They found the ISD-based sealants to have properties comparable to a Bis-GMA-based sealant and no estrogenicity. Sun et al. [179,180] tested the estrogenicity of two bio-based phenols and used these two phenols to prepare a series of BPA-free monomers (as shown in Figure 19), after confirming the absence of estrogenicity. Subsequently, they used these monomers to prepare Bis-GMA-free DRCs. Though these Bis-GMA-free DRCs exhibited acceptable physicochemical properties, certain properties still need to be improved to maintain the same level of performance as Bis-GMA-based DRCs.
Physical-chemical characterization and bond strength to zirconia of dental adhesives with different monomer mixtures and photoinitiator systems light-activated with poly and monowave devices
Published in Biomaterial Investigations in Dentistry, 2022
Constantino Fernandes Neto, Mayara Hana Narimatsu, Pedro Henrique Magão, Reginaldo Mendonça da Costa, Carmem Silvia Pfeifer, Adilson Yoshio Furuse
Adhesives are mainly composed of monomer mixtures and a photoinitiator system [7]. Monomers contain methacrylates that are responsible for binding to the silane coupling agent and forming the resin matrix with monomers of the cement, while photoinitiators trigger the polymerization reaction. The monomer mixture and the photoinitiator of choice will influence the final performance [8–10]. Bisphenol A glycidyl dimethacrylate (Bis-GMA) is a highly reactive monomer present in most adhesive and resin composite formulations. However, the presence of hydroxyl groups in its backbone increases its viscosity and lowers its degree of conversion (DC) [11]. In turn, the viscosity of the monomers greatly influences polymerization rate, since it determines the early onset of diffusion limitations to propagation [6,12]. For this reason, less viscous co-polymers such as triethylene glycol dimethacrylate (TEGDMA), ethoxylated bisphenol methacrylate (Bis-EMA), urethane dimethacrylate (UDMA) and 2-hydroxyethyl methacrylate (HEMA) are added [9,13]. In this sense, Bis-EMA appears as an interesting alternative due to its reported high DC and low water solubility [14]. The monomer composition is known to influence water sorption and solubility of the final polymer [15,16], which are crucial parameters to determine the longevity of the restorative interface [17]. Thus, varying monomer composition seems to be an alternative for providing a good interaction of luting agents with Y-TZP surface in the long-term.