Stevan M Cokic1, Radu C Duca2, Jan De Munck1, Peter Hoet2, Bart Van Meerbeek1, Mario Smet3, Lode Godderis4, Kirsten L Van Landuyt5. 1. KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium. 2. Centre for Environmental and Health, Department of Public Health and Primary Care, University of Leuven, Kapucijnenvoer 35, 3000 Leuven, Belgium. 3. Polymer Chemistry and Materials, Department of Chemistry, KU Leuven (University of Leuven), Celestijnenlaan 200f - Box 2404, 3000 Leuven, Belgium. 4. Centre for Environmental and Health, Department of Public Health and Primary Care, University of Leuven, Kapucijnenvoer 35, 3000 Leuven, Belgium; Idewe, External Service for Prevention and Protection at Work, Interleuvenlaan 58, B-3001 Heverlee, Belgium. 5. KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium. Electronic address: kirsten.vanlanduyt@med.kuleuven.be.
Abstract
OBJECTIVE: Accurate knowledge of the quantity of released monomers from composites is important. To evaluate the elution of monomers, polymerized composites are typically immersed in an extraction solvent. The objective was to determine whether the volume of extraction solvent and the immersion time influences monomer leachability from dental composite materials. METHODS: Composite disks of two commercial composites, (Filtek Supreme XTE, 3M ESPE and G-aenial Universal Flo, GC) were prepared. The disks (n=10) were placed in a glass vial with 1ml, 2ml or 3ml of extraction solvent (100% ethanol with deuterated diethylphalate as internal standard). After either 7 or 30 days at 37°C, the supernatant was collected and the amount of released monomers (BisEMA, BisGMA, UDMA, TEGDMA) and bisphenol A was measured with liquid chromatography mass spectroscopy. RESULTS: For both tested composites, the highest amount of released monomers was measured after sample incubation in 3ml, while the lowest amount was measured in 1ml of extraction solvent. Furthermore, 30 days did not result in much more monomer release compared to 7 days, and for most monomers, there was no statistically significant difference in release between 7 and 30 days. SIGNIFICANCE: Release kinetics in in-vitro experiments are also influenced by saturation of the extraction solvent with the leached monomers. This is important as it is unlikely that saturation can be reached in an in-vivo situation, where saliva (or pulpal fluid) is continuously refreshed. Saturation of the extraction solvent can be avoided in-vitro by refreshing the extraction medium after equal time intervals.
OBJECTIVE: Accurate knowledge of the quantity of released monomers from composites is important. To evaluate the elution of monomers, polymerized composites are typically immersed in an extraction solvent. The objective was to determine whether the volume of extraction solvent and the immersion time influences monomer leachability from dental composite materials. METHODS: Composite disks of two commercial composites, (Filtek Supreme XTE, 3M ESPE and G-aenial Universal Flo, GC) were prepared. The disks (n=10) were placed in a glass vial with 1ml, 2ml or 3ml of extraction solvent (100% ethanol with deuterated diethylphalate as internal standard). After either 7 or 30 days at 37°C, the supernatant was collected and the amount of released monomers (BisEMA, BisGMA, UDMA, TEGDMA) and bisphenol A was measured with liquid chromatography mass spectroscopy. RESULTS: For both tested composites, the highest amount of released monomers was measured after sample incubation in 3ml, while the lowest amount was measured in 1ml of extraction solvent. Furthermore, 30 days did not result in much more monomer release compared to 7 days, and for most monomers, there was no statistically significant difference in release between 7 and 30 days. SIGNIFICANCE: Release kinetics in in-vitro experiments are also influenced by saturation of the extraction solvent with the leached monomers. This is important as it is unlikely that saturation can be reached in an in-vivo situation, where saliva (or pulpal fluid) is continuously refreshed. Saturation of the extraction solvent can be avoided in-vitro by refreshing the extraction medium after equal time intervals.