title: Cytotoxic effects of composite dust on human bronchial epithelial cells.
abstract: Previous research revealed that during routine abrasive procedures like polishing, shaping or removing of composites, high amounts of respirable dust particles (<5μm) including nano-sized particles (<100nm) may be released.
  
  
  
  To determine the cytotoxic potential of composite dust particles on bronchial epithelium cells.
  
  
  
  Composite dust of five commercial composites (one nano-composite, two nano-hybrid and two hybrid composites) was generated following a clinically relevant protocol. Polymerized composite samples were cut with a rough diamond bur (grain size 100μm, speed 200,000rpm) and all composite dust was collected in a sterile chamber. Human bronchial epithelial cells (16HBE14o-) were exposed to serially diluted suspensions of composite dust in cell culture medium at concentrations between 1.1 and 3.3mg/ml. After 24h-exposure, cell viability and membrane integrity were assessed by the WST-1 and the LDH leakage assay, respectively. The release of IL-1β and IL-6 was evaluated. The composite dust particles were characterized by transmission electron microscopy and by dynamic and electrophoretic light scattering.
  
  
  
  Neither membrane damage nor release of IL-1β was detected over the complete concentration range. However, metabolic activity gradually declined for concentrations higher than 660μg/ml and the release of IL-6 was reduced when cells were exposed to the highest concentrations of dust.
  
  
  
  Composite dust prepared by conventional dental abrasion methods only affected human bronchial epithelial cells in very high concentrations.
authors.affiliation: KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium.
authors.forename: Stevan M
authors.initials: SM
authors.lastname: Cokic
authors.affiliation: Centre for Environmental and Health, Department of Public Health and Primary Care, KU Leuven (University of Leuven), Kapucijnenvoer 35, 3000 Leuven, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: Hoet
authors.affiliation: Centre for Environmental and Health, Department of Public Health and Primary Care, KU Leuven (University of Leuven), Kapucijnenvoer 35, 3000 Leuven, Belgium; IDEWE, External Service for Prevention and Protection at Work, Heverlee, Belgium.
authors.forename: Lode
authors.initials: L
authors.lastname: Godderis
authors.affiliation: IBE R&D gGmbH, Institute for Lung Health, Mendelstraße 11, 48149 Münster, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Wiemann
authors.affiliation: Institute of Energy and Environmental Technology (IUTA) e.V., Bliersheimer Straße 60, 47229 Duisburg, Germany.
authors.forename: Christof
authors.initials: C
authors.lastname: Asbach
authors.affiliation: Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University of Munich, Nussbaumstraße 26, 80336 Munich, Germany.
authors.forename: Franz X
authors.initials: FX
authors.lastname: Reichl
authors.affiliation: KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium.
authors.forename: Jan
authors.initials: J
authors.lastname: De Munck
authors.affiliation: KU Leuven BIOMAT, Department of Oral Health Sciences, University of Leuven & Dentistry University Hospitals Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium.
authors.forename: Bart
authors.initials: B
authors.lastname: Van Meerbeek
authors.affiliation: 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.
authors.forename: Kirsten L
authors.initials: KL
authors.lastname: Van Landuyt
mesh_terms: D002462:Cell Membrane / Q000187:drug effects; D003188:Composite Resins / Q000633:toxicity*; D004391:Dust; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6; D008168:Lung / Q000166:cytology; D010316:Particle Size
chemical_list: D003188:Composite Resins; D004391:Dust; D053583:Interleukin-1beta; D015850:Interleukin-6
keywords: Composite dust; Cytotoxicity; Dental composite; Human bronchial cells; Nano-particle; TEM