title: Effect of placement techniques on the marginal adaptation of Class V composite restorations.
abstract: BACKGROUND
  Several techniques are proposed for the restoration of Class V cavities but there is no agreement in the literature as to which technique is more effective.
  
  
  OBJECTIVE
  To evaluate the effect of different techniques of composite increment placement on the marginal adaptation of Class V restorations.
  
  
  METHODS
  Twenty-four human molars were selected and prepared with standardized saucer-shaped cavity dimensions of 3.0 mm (occlusal-gingival), 2.0 mm (mesial-distal), and 2.0 mm (depth). The margins are in reference to the cemento-enamel junction with 1.5 mm being located on enamel and 1.5 mm on dentin. The cavities were randomly assigned into three groups (n=8) and restored with composites as follows: Group 1, the occlusal increment was placed and cured first followed by the gingival increment; Group 2, the gingival increment was placed and cured first followed by the occlusal increment; and Group 3, the cavities were restored with one bulk increment. Restorations were immediately finished and stored for 24 h in tap water. Specimens were subjected to thermocycling (1000 cycles, 5 degrees C to 55 degrees C, 30 s dwell time) and immersed in 0.5% basic fuchsin solution for 24 h in room temperature. After rinsing with running water, the restorations were sectioned longitudinally and enamel and dentin margins were evaluated and scored according to the microleakage on a 0-3 scale. Data were subjected to Kruskal-Wallis test at p<0.05.
  
  
  RESULTS
  Median of microleakage scores for all evaluated groups was zero. No statistical difference was observed among the three groups both in enamel (p = 0.5929) and dentin (p = 0.3679) margins
  
  
  CONCLUSIONS
  The placement technique did not influence the marginal adaptation of moderate Class V restorations.
  
  
  CONCLUSIONS
  No differences on marginal adaptation were observed when restoring conservative Class V cavities using incremental or bulk placement techniques.
authors.affiliation: Department of Operative Dentistry, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil. luis_sensi@hotmail.com
authors.forename: Luis Guilherme
authors.initials: LG
authors.lastname: Sensi
authors.forename: Fabiano Carlos
authors.initials: FC
authors.lastname: Marson
authors.forename: Luiz Narciso
authors.initials: LN
authors.lastname: Baratieri
authors.forename: Sylvio
authors.initials: S
authors.lastname: Monteiro Junior
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate; D003188:Composite Resins; D001840:Dental Bonding; D003763:Dental Leakage / Q000517:prevention & control*; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000379:methods*; D006801:Humans; D008963:Molar; D011897:Random Allocation; D019279:Resin Cements; D018709:Statistics, Nonparametric
chemical_list: D003188:Composite Resins; C474035:Filtek Supreme; D019279:Resin Cements; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate