Nick J Walters1, Wendy Xia2, Vehid Salih3, Paul F Ashley4, Anne M Young5. 1. Division of Biomaterials & Tissue Engineering, UCL Eastman Dental Institute, 256 Gray's Inn Road, London WC1X 8LD, UK. Electronic address: nick.walters@uta.fi. 2. Division of Biomaterials & Tissue Engineering, UCL Eastman Dental Institute, 256 Gray's Inn Road, London WC1X 8LD, UK. 3. Division of Biomaterials & Tissue Engineering, UCL Eastman Dental Institute, 256 Gray's Inn Road, London WC1X 8LD, UK; Plymouth University Peninsula Schools of Medicine and Dentistry, Portland Square, Drake Circus, Plymouth, Devon PL4 8AA, UK. 4. Paediatric Dentistry, UCL Eastman Dental Institute, 256 Gray's Inn Road, London WC1X 8LD, UK. 5. Division of Biomaterials & Tissue Engineering, UCL Eastman Dental Institute, 256 Gray's Inn Road, London WC1X 8LD, UK. Electronic address: anne.young@ucl.ac.uk.
Abstract
OBJECTIVES: To determine the effects of various monomers on conversion and cytocompatibility of dental composites and to improve these properties without detrimentally affecting mechanical properties, depth of cure and shrinkage. METHODS: Composites containing urethane dimethacrylate (UDMA) or bisphenol A glycidyl methacrylate (Bis-GMA) with poly(propylene glycol) dimethacrylate (PPGDMA) or triethylene glycol dimethacrylate (TEGDMA) were characterized using the following techniques: conversion (FTIR at 1 and 4mm depths), depth of cure (BS EN ISO 4049:2009 and FTIR), shrinkage (BS EN ISO 17304:2013 and FTIR), strength and modulus (biaxial flexural test) and water sorption. Cytocompatibility of composites and their liquid phase components was assessed using three assays (resazurin, WST-8 and MTS). RESULTS: UDMA significantly improved conversion, BFS and depth of cure compared to Bis-GMA, without increasing shrinkage. UDMA was cytotoxic at lower concentrations than Bis-GMA, but extracts of Bis-GMA-containing composites were less cytocompatible than of those containing UDMA. PPGDMA improved conversion and depth of cure compared to TEGDMA, without detrimentally affecting shrinkage. TEGDMA was shown by all assays to be highly toxic. Resazurin, but not WST-8 and MTS, suggested that PPGDMA exhibited improved cytocompatibility compared to TEGDMA. SIGNIFICANCE: The use of UDMA and PPGDMA results in composites with excellent conversion, depth of cure and mechanical properties, without increasing shrinkage. Composites containing UDMA appear to be slightly more cytocompatible than those containing Bis-GMA. These monomers may therefore improve the material properties of dental restorations, particularly bulk fill materials. The effect of diluent monomer on cytocompatibility requires further investigation.
OBJECTIVES: To determine the effects of various monomers on conversion and cytocompatibility of dental composites and to improve these properties without detrimentally affecting mechanical properties, depth of cure and shrinkage. METHODS: Composites containing urethane dimethacrylate (UDMA) or bisphenol A glycidyl methacrylate (Bis-GMA) with poly(propylene glycol) dimethacrylate (PPGDMA) or triethylene glycol dimethacrylate (TEGDMA) were characterized using the following techniques: conversion (FTIR at 1 and 4mm depths), depth of cure (BS EN ISO 4049:2009 and FTIR), shrinkage (BS EN ISO 17304:2013 and FTIR), strength and modulus (biaxial flexural test) and water sorption. Cytocompatibility of composites and their liquid phase components was assessed using three assays (resazurin, WST-8 and MTS). RESULTS: UDMA significantly improved conversion, BFS and depth of cure compared to Bis-GMA, without increasing shrinkage. UDMA was cytotoxic at lower concentrations than Bis-GMA, but extracts of Bis-GMA-containing composites were less cytocompatible than of those containing UDMA. PPGDMA improved conversion and depth of cure compared to TEGDMA, without detrimentally affecting shrinkage. TEGDMA was shown by all assays to be highly toxic. Resazurin, but not WST-8 and MTS, suggested that PPGDMA exhibited improved cytocompatibility compared to TEGDMA. SIGNIFICANCE: The use of UDMA and PPGDMA results in composites with excellent conversion, depth of cure and mechanical properties, without increasing shrinkage. Composites containing UDMA appear to be slightly more cytocompatible than those containing Bis-GMA. These monomers may therefore improve the material properties of dental restorations, particularly bulk fill materials. The effect of diluent monomer on cytocompatibility requires further investigation.
Authors: Piyaphong Panpisut; Muhammad Adnan Khan; Kirsty Main; Mayda Arshad; Wendy Xia; Haralampos Petridis; Anne Margaret Young Journal: PLoS One Date: 2019-03-18 Impact factor: 3.240
Authors: Kanokrat Kangwankai; Sarah Sani; Piyaphong Panpisut; Wendy Xia; Paul Ashley; Haralampos Petridis; Anne Margaret Young Journal: PLoS One Date: 2017-11-14 Impact factor: 3.240