title: Effect of insertion technique and adhesive system on microleakage of Class V resin composite restorations.
abstract: OBJECTIVE
  To evaluate the effect of different insertion techniques and adhesive systems on microleakage of Class V composite resin restorations.
  
  
  METHODS
  Forty-eight human molars were randomly assigned to four groups (n = 12). Standardized mixed Class V cavities (enamel and dentin margins) were prepared at the CEJ. A total-etch (Adper Scotchbond MultiPurpose) and a self-etching (iBond) adhesive system were evaluated using either an incremental or single-step (bulk) insertion technique. The preparations were restored with Esthet*X micromatrix hybrid composite. The teeth were thermocycled 1000 cycles, immersed in 1% methylene blue dye for 24 h, and invested in acrylic resin. The specimen blocks were then sectioned longitudinally, with dye penetration (microleakage) examined with a 20X binocular microscope. Enamel and dentin margins were scored separately for microleakage using an ordinal ranking system. Results were analyzed using non-parametric tests at a p < 0.05 level of significance.
  
  
  RESULTS
  Significance was exhibited between the groups (adhesive material/insertion technique) at the coronal and apical margins. At the coronal margin, the total-etch adhesive/incremental insertion group exhibited significantly less leakage than the other groups, while at the apical margin, the total-etch adhesive/incremental insertion group showed significantly less leakage than the self-etching adhesive/bulk insertion group. Significantly less leakage was found at the coronal margins compared to the apical margins of the material/technique groups.
  
  
  CONCLUSIONS
  The use of a total-etch adhesive system and incremental insertion of composite significantly reduced microleakage at the coronal and apical margins of Class V composite restorations.
authors.affiliation: Department of Restorative Dentistry, College of Dentistry, University of Tennessee, Memphis, TN 38163, USA. bowens@utmem.edu
authors.forename: Barry M
authors.initials: BM
authors.lastname: Owens
authors.forename: William W
authors.initials: WW
authors.lastname: Johnson
mesh_terms: D004396:Coloring Agents; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding / Q000379:methods*; D003737:Dental Cavity Preparation / Q000145:classification; D003743:Dental Enamel / Q000033:anatomy & histology; D003763:Dental Leakage / Q000145:classification*; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry*; D003793:Dental Restoration, Permanent / Q000145:classification* / Q000379:methods; D003804:Dentin / Q000033:anatomy & histology; D017220:Dentin-Bonding Agents / Q000737:chemistry; D006801:Humans; D008751:Methylene Blue; D019279:Resin Cements / Q000737:chemistry; D019237:Tooth Cervix / Q000033:anatomy & histology
chemical_list: D004396:Coloring Agents; D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C466112:Esthet-X; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; C477386:iBond; D008751:Methylene Blue