Novel Urethane-Dimethacrylate Monomers and Compositions for Use as Matrices in Dental Restorative Materials

Abstract

In this study, novel urethane-dimethacrylate monomers were synthesized from 1,3-bis(1-isocyanato-1-methylethyl)benzene (MEBDI) and oligoethylene glycols monomethacrylates, containing one to three oxyethylene groups. They can potentially be utilized as matrices in dental restorative materials. The obtained monomers were used to prepare four new formulations. Two of them were solely composed of the MEBDI-based monomers. In a second pair, a monomer based on triethylene glycol monomethacrylate, used in 20 wt.%, was replaced with triethylene glycol dimethacrylate (TEGDMA), a reactive diluent typically used in dental materials. For comparison purposes, two formulations, using typical dental dimethacrylates (bisphenol A glycerolate dimethacrylate (Bis-GMA), urethane-dimethacrylate (UDMA) and TEGDMA) were prepared. The monomers and mixtures were tested for the viscosity and density. The homopolymers and copolymers, obtained via photopolymerization, were tested for the degree of conversion, polymerization shrinkage, water sorption and solubility, hardness, flexural strength and modulus. The newly developed formulations achieved promising physico-chemical and mechanical characteristics so as to be suitable for applications as dental composite matrices. A combination of the MEBDI-based urethane-dimethacrylates with TEGDMA resulted in copolymers with a high degree of conversion, low polymerization shrinkage, low water sorption and water solubility, and good mechanical properties. These parameters showed an improvement in relation to currently used dental formulations.

Clinical Effectiveness of Bulk-Fill and Conventional Resin Composite Restorations: Systematic Review and Meta-Analysis

“…Preferably, these restorations should also prevent biofilm attachment, present remineralization capabilities, and be able to self-repair. To date, no commercially available material is able to meet all of these requirements [ 3 ], however attempts are being made to develop new resin materials containing bisphenol A-free monomers [ 4 ]. According to the guidelines of the Academy of Dental Materials [ 5 ], the highest priorities for evaluating resin composites are strength, elastic modulus, fracture toughness, fatigue, indentation hardness, and wear (abrasion and attrition) measurements.…”

A Low-Viscosity BisGMA Derivative for Resin Composites: Synthesis, Characterization, and Evaluation of Its Rheological Properties

“…It has strong advantages over its (di)(meth)acrylate-based analogs, including its low polymerization shrinkage, suitable mechanical properties, relatively high refractive index, and excellent adhesion to enamel [ 9 , 10 ]. The major disadvantage of BisGMA is its high viscosity [ 9 ], which prevents the addition of high contents of fillers. On the molecular level, BisGMA has a stiff central aromatic core and two hydroxyl groups that kinetically cause a reduced degree of molecular freedom.…”

“…As polymerization proceeds, the movement of the macro-radicals becomes more restricted, and thereafter, diffusion-controlled process being the dominant mechanism of propagation and termination [ 6 , 13 ]. To obtain suitable low-viscose monomers, scientists have synthesized different BisGMA-alike monomers [ 7 , 9 ]. Others tried the fabrication of the BisGMA chemical structure by, for example, synthesizing various derivatives [ 5 , 12 , 14 , 15 , 16 , 17 ]; however, reaching the state-of-the-art monomer with low viscosity and superior properties for dental restorations is one current objective for specialists.…”

Physical and Mechanical Properties of Resins Blends Containing a Monomethacrylate with Low-polymerization Shrinkage

“…[1][2][3] Dental composites are derived from methacrylate networks, and the base monomer most currently used in these composites is bisphenol glycidyl methacrylate (Bis-GMA), known to be somewhat volatile, low diffusivity between tissues and low shrinkage. 2 The high viscosity of Bis-GMA monomers requires the addition of low-molecular weight monomer to obtain a suitable viscosity and improve mobility of the monomers during the polymerization reaction, increasing the degree of conversion 4,5 , in addition to providing the incorporation of inorganic particle fillers. 4,6 Due to its low viscosity and ability to increase the degree of conversion, triethyleneglycol dimethacrylate (TEGDMA) is a diluent monomer widely added to the base monomer.…”

“…2 The high viscosity of Bis-GMA monomers requires the addition of low-molecular weight monomer to obtain a suitable viscosity and improve mobility of the monomers during the polymerization reaction, increasing the degree of conversion 4,5 , in addition to providing the incorporation of inorganic particle fillers. 4,6 Due to its low viscosity and ability to increase the degree of conversion, triethyleneglycol dimethacrylate (TEGDMA) is a diluent monomer widely added to the base monomer. 4,7 However, TEGDMA has high volumetric shrinkage (VS).…”