title: Thiol-ene oligomers as dental restorative materials.
abstract: OBJECTIVE
  The aim of this work was to prereact thiol-ene monomers to create reactive thiol or vinyl (ene)-functionalized oligomers, and to investigate the use of these materials as novel dental restorative material. Investigation has focused on the application of oligomeric thiol-ene materials as dental restorative resins with lower polymerization shrinkage and polymerization stress as compared to monomeric thiol-ene systems and particularly with respect to current dimethacrylate-based systems.
  
  
  METHODS
  Reactive thiol-functionalized oligomers were created via photopolymerization using triallyl-1,3,5-triazine-2,4,6-trione (TATATO), trimethylolpropane tris(3-mercaptopropionate) (trithiol) and pentaerythritol tetramercaptopropionate (tetrathiol). Kinetic and mechanical investigation of Bis-GMA/TEGDMA, and oligomeric and monomeric thiol-ene systems were conducted. More specifically, polymerization shrinkage and stress, polymerization kinetics, glass transition temperature, flexural strength and flexural modulus were evaluated.
  
  
  RESULTS
  Upon evaluation, the polymerization stress of oligomeric thiol-ene systems was dramatically reduced by as much as 33% when compared with the stress exhibited by monomeric thiol-ene systems and as much as a 92% reduction in stress relative to the current dimethacrylate-based dental restorative materials. Furthermore, the flexural strength and modulus of the monomeric and oligomeric thiol-ene resins were not significantly different.
  
  
  CONCLUSIONS
  Oligomeric thiol-ene systems offer potential as alternative dental restorative resins due to the significant reduction in polymerization shrinkage and stress while retaining the mechanical properties of monomer-based thiol-ene resins.
authors.affiliation: Department of Chemical and Biological Engineering, Engineering Center, University of Colorado at Boulder, ECCH 111, 80309-0424, USA.
authors.forename: Jacquelyn A
authors.initials: JA
authors.lastname: Carioscia
authors.forename: Hui
authors.initials: H
authors.lastname: Lu
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Stanbury
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Bowman
mesh_terms: D015097:3-Mercaptopropionic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D000498:Allyl Compounds / Q000737:chemistry*; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D004548:Elasticity; D006801:Humans; D007700:Kinetics; D008422:Materials Testing; D018583:Pliability; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011409:Propylene Glycols / Q000737:chemistry*; D013314:Stress, Mechanical; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties; D044366:Transition Temperature; D014227:Triazines / Q000737:chemistry*
chemical_list: D000498:Allyl Compounds; D003188:Composite Resins; D003764:Dental Materials; D011108:Polymers; D011109:Polymethacrylic Acids; D011409:Propylene Glycols; D013438:Sulfhydryl Compounds; D014227:Triazines; C501435:pentaerythritol tetra(3-mercaptopropionate); C507611:triallyl-1,3,5-triazine-2,4,6-trione; C018163:trimethylolpropane; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; D015097:3-Mercaptopropionic Acid