Acrylamides and methacrylamides as alternative monomers for dental adhesives. Issue 11 (November 2018)

• Record Type: Journal Article
• Authors: Rodrigues, Stéfani Becker; Petzhold, Cesar Liberato; Gamba, Douglas; Leitune, Vicente Castelo Branco; Collares, Fabrício Mezzomo
• Is Part Of: Dental materials. Volume 34:Issue 11(2018)
• Page Start: 1634
• Page End: 1644
• Publication Date: 2018-11
• Subjects: Organic synthesis -- Dental adhesives -- Acrylamides -- Differential Scanning Calorimetry -- Cytotoxicity -- Degree of conversion; Dentistry -- Periodicals; Dental materials -- Periodicals; 617.695
• DOI: 10.1016/j.dental.2018.08.296
• Languages: English
• ISSNs: 0109-5641

Abstract

Highlights: New synthetic route for tris(methacrylamide) was proposed, and monomer was characterized. Primer composed by acrylamides was formulated for 3-step etch-and-rise adhesive system. Trifunctional methacrylamide monomer in adhesive resin increase of mechanical properties and represents an alternative adhesive resin without HEMA monomer. Abstract: Objective: Synthesize and characterize a methacrylamide monomer for adhesive system and evaluate the physicochemical properties of the adhesive resin. Methods: The liquid methacrylamide monomer N, N′, N ″ - (nitrilotris(ethane-2, 1-dyil)tris(2-methylacrylamide) (TMA) was prepared by reaction of methacrylic anhydride and tris(2-aminoethyl)amine with 60% yields. The TMA structure was analyzed by 1 H NMR, 13 C NMR, ATR-FTIR and UHPLC-QTOF-MS. Experimental adhesive resin containing bisphenol-A glycidyl methacrylate (BISGMA), 2-hydroxyethylacrylamide (HEAA), 2-hydroxyethylmethacrylate (HEMA) and TMA were formulated. Polymerization kinetics of neat TMA and experimental adhesive resin (TMA33%/HEAA66%, TMA50%/HEAA50%, TMA66%/HEAA33%, TMA50%/HEMA50%, BisGMA/HEAA/TMA and BisGMA/HEMA) were evaluated using Differential Scanning Calorimetry. Physiochemical properties for BisGMA/HEAA/TMA and BisGMA/HEMA adhesives were evaluated by cytotoxicity, ultimate tensile strength (UTS), softening in solvent (ΔKHN), contact angle (θ), microtensile bond strength (μTBS) and failure analysis. A primer was also formulated with H2 O/HEAA/AMPS (2-acrylamido-2-methylpropane sulfonic acid) and the pH value was verified and compared to commercial primer. Results: Adhesive resin with only HEAA and TMA (TMA33%/HEAA66%, TMA50%/HEAA50%, TMA66%/HEAA33%) showed lower conversion and polymerization rate after 40 s of light activation. Conversion up to 60% was found for BisGMA/HEAA/TMA and BisGMA/HEMA adhesive resin without significant difference between groups, p > 0.05. Cytotoxicity, UTS, μTBS, ΔKHN and θ showed no statistical difference, p > 0.05, between BisGMA/HEAA/TMA and BisGMA/HEMA adhesive resin. Significance: In this study, the proposed synthetic route resulted in a tris(methacrylamide). A new primer composed without acrylates or methacrylates was formulated for 3-step etch-and-rinse adhesive system without the presence of HEMA monomer. Physicochemical properties and cell viability of BisGMA/HEAA/TMA adhesive resin represents an alternative adhesive resin without HEMA monomer.