New urethane oligodimethacrylates with quaternary alkylammonium for formulating dental composites

Abstract

The aim of this study was to prepare urethane dimethacrylates containing quaternary alkyl (C16, C12) ammonium and polyethylene glycol short sequences (Mn, 400 g/mol) and to investigate their behaviour in some experimental formulations in order to evaluate their potential applicability in the dental composites field. The structure of urethane dimethacrylates has been confirmed by (1)H ((13)C) NMR and FTIR spectra, as well as by electrospray ionization tandem mass spectroscopy, and gel permeation chromatography measurements. The effects of the cationic macromers on the properties of the filled/non-filled composites were examined through FTIR, photoDSC, and specific measurements as volumetric polymerization shrinkage, water sorption/solubility, contact angle, mechanical parameters, and morphology. The monomer compositions based on cationic dimethacrylate (6.88-27.52 wt%), BisGMA-analogue (48.18-68.82 wt%) and TEGDMA (23.3 wt%) showed a good photoreactivity in terms of double bond conversion (DC, 50.07-68.81 %) and polymerization rate (Rp, 0.099-0.141 s(-1)) measured by photoDSC compared to a control sample (BisGMA-1/TEGDMA: DC, 45.91 %; Rp, 0.162 s(-1)), while the polymerization shrinkage increased in acceptable limits (5.37-7.74 vol%). The mechanical properties (compressive, flexural and diametral tensile strength) of the composite resin incorporating 70 wt% silanized zirconium silicate micro/nanopowder can be modulated by the initial co-monomer concentrations.

Isocyanate‐Free, UV‐Crosslinked Poly(Hydroxyurethane) Networks: A Sustainable Approach toward Highly Functional Antibacterial Gels

“…A reduction of 0–95.4% was seen when seeded with 10 4 CFU of bacteria . More often, PU networks are made into composites with other antibacterial moieties, which also show good properties …”

“…[16] More often, PU networks are made into composites with other antibacterial moieties, which also show good properties. [32][33][34] The detailed killing mechanisms for both Gram-positive and Gram-negative bacteria have been reported and reviewed extensively in the previous literature. [13] Immobilized QACs are known to show contact killing ability where the positive charge carried by the QACs accounts for the major antibacterial function.…”

Microstructural Features of Current Resin Composite Materials

“…These products have been demonstrated to regulate bacterial adhesion and colonization [71,72], as well as to pose potential toxicity concerns, especially when used in dental adhesives [72][73][74][75]. Several direct restorative materials are in fact conducive of biofilm colonization, and therefore, antimicrobial composites have also been proposed [76,77]. The most common approaches are based either on charged sites within the monomer (e.g., quaternary alkylammonium functionalities) [76,78], or the addition of triclosan monomer units [77] or Irgasan-containing delivery beads [79].…”

“…Several direct restorative materials are in fact conducive of biofilm colonization, and therefore, antimicrobial composites have also been proposed [76,77]. The most common approaches are based either on charged sites within the monomer (e.g., quaternary alkylammonium functionalities) [76,78], or the addition of triclosan monomer units [77] or Irgasan-containing delivery beads [79]. While general mechanical properties and polymerization efficiency remain unaltered in comparison to conventional counterparts, the biological activity and substantivity of such materials remain to be elucidated.…”

Ester-free thiol–ene dental restoratives—Part B: Composite development

“…A multitude of approaches have been undertaken to improve subsequent generations of dimethacrylate composites. Urethane dimethacrylates and other low-shrinkage resins have been developed by synthesis of high molecular weight monomers and oligomers, or alternatively by employing a ring-opening polymerization mechanism, to reduce the shrinkage [16–19], . In recent years chain transfer reactions have been implemented within methacrylate polymerizations by thiol and ene inclusion [20–22] or specifically designed addition fragmentation monomers have been considered [23,24].…”