title: Effect of prepolymerized composite megafiller on the marginal adaptation of composite restorations in cavities with different C-factors: an SEM study.
abstract: OBJECTIVE
  To evaluate the effect of prepolymerized custom-made composite megafiller and configuration factors (C-factor) on marginal adaptation of resin composite restorations.
  
  
  METHODS
  Forty extracted human mandibular molars were divided into four experimental groups consisting of 10 samples each. In groups I and III, class V (configuration factor 5) and in groups II and IV, class II box-shaped cavities (configuration factor 2) were prepared. Groups I and II were restored with a nanofilled composite (Filtek™ Z350 3M ESPE, St Paul, MN, USA) placed in horizontal increments. In groups III and IV, preformed composite megafiller was placed and cavities were restored with nanofilled composite Z-350. After curing, the samples were finished and prepared for examination under low vacuum scanning electron microscope. The data were analyzed with one-way analysis of variance. The significance between the individual groups was calculated by Post hoc test using the Holm-Sidak method ( P≤0.05).
  
  
  RESULTS
  The marginal gap values in groups III and IV were significantly lower than in groups I and II, respectively ( P≤0.05). Minimum gap values were seen in group IV.
  
  
  CONCLUSIONS
  Use of prepolymerized composite megafiller and a lower C-factor decreased the marginal gaps between the tooth and composite restorations.
authors.affiliation: Department of Conservative Dentistry and Endodontics, All India Institute of Medical Sciences, New Delhi, India. dr.saruendo2007@gmail.com
authors.forename: Sarita
authors.initials: S
authors.lastname: Bhushan
authors.forename: Ajay
authors.initials: A
authors.lastname: Logani
authors.forename: Naseem
authors.initials: N
authors.lastname: Shah
mesh_terms: D000134:Acid Etching, Dental; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D003737:Dental Cavity Preparation / Q000145:classification*; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing; D003793:Dental Restoration, Permanent / Q000145:classification*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008963:Molar / Q000648:ultrastructure; D053761:Nanocomposites / Q000737:chemistry; D010756:Phosphoric Acids / Q000737:chemistry; D058105:Polymerization; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties; D015040:Zirconium / Q000737:chemistry
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D010756:Phosphoric Acids; C533204:filtek Z350; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate; D012822:Silicon Dioxide; D015040:Zirconium; C030242:phosphoric acid; C028541:zirconium oxide