title: Bonding of resin composite precured or postcured to primary dentin.
abstract: OBJECTIVE
  The purpose of this study was to examine in vitro the effect of cure mode on the shear bond strength (SBS), failure mode (FM), microleakage (ML), and resin tag penetration (RTP) of two resin composite (RC)/adhesive systems: (1) Clearfil Majesty Esthetic/Clearfil SE Bond (CME/SEB); and (2) TPH 3 Micro Matrix Restorative/Prime&Bond NT (TPH/P&B).
  
  
  METHODS
  Paired RC samples (10 CME/SEB; 10 TPH/P&B) were precured or postcured with adhesive on primary molar dentinal substrates and tested for SBS (10 per group); debonded surfaces were examined. Cavities (Class V) in extracted primary molars were restored (20 CME/SEB; 20 TPH/P&B), following precuring or postcuring the adhesive, and examined for ML (eight per group) and RTP (two per group).
  
  
  RESULTS
  Mean SBS (MPa) values differed: precured CME/SEB exceeded postcured CME/SEB (20.16±2.70 versus 10.97±4.39; P<.001), and postcured TPH/P&B exceeded precured TPH/P&B (14.17±3.73 versus 11.10±2.62; P=.007). The FM differed between systems: CME/SEB: precured (four adhesive-dentin; six mixed), postcured (10 adhesive-dentin); TPH/P&B: precured (10 adhesive-dentin), postcured (nine adhesive-dentin; one mixed). Only one specimen showed true ML (postcured TPH/P&B). The RTP was greater in postcured than precured specimens.
  
  
  CONCLUSIONS
  Precured CME/SEB was deemed superior for restoration of primary teeth, despite extra time required clinically to precure the adhesive.
authors.affiliation: School Dental Service, Health Promotion Board, Singapore.
authors.forename: Wanyi
authors.initials: W
authors.lastname: Lim
authors.affiliation: Melbourne Dental School, The University of Melbourne, Melbourne, Victoria, Australia. ljbm@unimelb.edu.au.
authors.forename: Louise B
authors.initials: LB
authors.lastname: Messer
authors.affiliation: Melbourne Dental School, The University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Joseph E A
authors.initials: JE
authors.lastname: Palamara
mesh_terms: D000268:Adhesiveness; D004396:Coloring Agents; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003737:Dental Cavity Preparation / Q000379:methods; D003763:Dental Leakage / Q000145:classification; D003764:Dental Materials / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D003804:Dentin / Q000648:ultrastructure*; D006801:Humans; D006813:Humidity; D008422:Materials Testing; D008751:Methylene Blue; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D033081:Shear Strength; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014094:Tooth, Deciduous / Q000648:ultrastructure*
chemical_list: C438313:Clearfil SE Bond; D004396:Coloring Agents; D003188:Composite Resins; D003764:Dental Materials; D011109:Polymethacrylic Acids; C425843:Prime and Bond NT; D019279:Resin Cements; C113300:TPH hybrid; C541508:clearfil majesty; D008751:Methylene Blue