title: Cuspal deflection and cervical microleakage scores to determine the adhesive potential of universal bonding systems.
abstract: OBJECTIVE
  To assess the adhesive performance of three universal bonding systems (self-etch and total-etch protocols) with cuspal deflection and cervical microleakage score.
  
  
  METHODS
  Fifty-six standardised sound maxillary premolar teeth with uniform mesio-occlusal-distal (MOD) cavities were randomly allocated to six groups. Restoration with resin-based composite (RBC) was performed in conjunction with a universal bonding system facilitated by a quartz-tungsten-halogen light-curing-unit. The dependent variable was the universal bonding protocol (self-etch or total-etch). Buccal and palatal cuspal deflections were recorded at 0, 30, 60 and 180s post-irradiation using a twin channel deflection measuring gauge. Following restoration, the teeth subjected to 500 thermocycles, immersed in a 0.2% basic fuchsin dye for 24h, sectioned and examined for cervical microleakage.
  
  
  RESULTS
  Comparing between bonding protocol (self-etch or total-etch), a decrease in total cuspal deflection and a concomitant increase in cervical microleakage were evident when employing the total-etch compared with the self-etch protocol for two of the three universal dental adhesives.
  
  
  CONCLUSIONS
  The 'Adhesion-Decalcification concept' suggests a trend towards 'mild self-etch' adhesives. Differences in adhesive performance (cuspal deflection and cervical microleakage) between the teeth restored using the self-etch or total-etch protocols is suggested to be a result of the pH of the self-etch solutions. 'Mild self-etch' (pH∼2.0) adhesives out-performed ultra-mild (pH>2.5) or strong (pH<1.5) self-etch solutions.
  
  
  CONCLUSIONS
  Poorly performing adhesives could be identified using the cuspal deflection and cervical microleakage protocol reported which could save the complications encountered clinically with Class II RBC restorations.
authors.affiliation: Materials Science Unit, Division of Oral Biosciences, Dublin Dental University Hospital, Lincoln Place, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: Jennifer O
authors.initials: JO
authors.lastname: Kearns
authors.affiliation: Materials Science Unit, Division of Oral Biosciences, Dublin Dental University Hospital, Lincoln Place, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: John G
authors.initials: JG
authors.lastname: Barry
authors.affiliation: Materials Science Unit, Division of Oral Biosciences, Dublin Dental University Hospital, Lincoln Place, Trinity College Dublin, Dublin 2, Ireland. Electronic address: garry.fleming@dental.tcd.ie.
authors.forename: Garry J P
authors.initials: GJ
authors.lastname: Fleming
mesh_terms: D001641:Bicuspid / Q000033:anatomy & histology / Q000502:physiology; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D004396:Coloring Agents; D003188:Composite Resins / Q000737:chemistry*; D055117:Curing Lights, Dental / Q000145:classification; D001840:Dental Bonding / Q000379:methods*; D003763:Dental Leakage / Q000145:classification*; D003764:Dental Materials / Q000737:chemistry*; D003793:Dental Restoration, Permanent / Q000379:methods; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D018583:Pliability; D011109:Polymethacrylic Acids / Q000737:chemistry; D011897:Random Allocation; D019279:Resin Cements / Q000737:chemistry*; D012394:Rosaniline Dyes; D013696:Temperature; D019237:Tooth Cervix / Q000033:anatomy & histology*; D019228:Tooth Crown / Q000502:physiology*
chemical_list: D004396:Coloring Agents; D003188:Composite Resins; D003764:Dental Materials; C474035:Filtek Supreme; C509998:Grandio; D008689:Methacrylates; D011109:Polymethacrylic Acids; C103500:Prime & Bond; C408584:Prompt L-Pop; D019279:Resin Cements; D012394:Rosaniline Dyes; C467914:TPH spectrum; C512545:futurabond NR; D017438:Bisphenol A-Glycidyl Methacrylate; C025485:basic fuchsin; C041330:Scotchbond
keywords: Cervical microleakage score; Cuspal deflection measurement; Resin-based composite; Universal bonding systems