title: Polymerization shrinkage and microleakage in Class II cavities of various resin composites.
abstract: This study investigated the polymerization shrinkage of restorative materials and microleakage in the proximal box of Class II restorations. Twenty caries free extracted human molars were prepared on the mesial and distal, making 40 slot cavities. Groups (n=10) were classified as: Group 1: Single bond/Filtek Z-250; Group 2: Single Bond/Filtek Flow/Filtek Z-250; Group 3: Admira Bond/Admira; Group 4: Ariston Liner/Ariston. Dentin bonding systems and resin composites were applied according to the manufacturer's instructions. The specimens were stored in distilled water for one week at 37 degrees C, thermocycled (5 degrees-55 degrees C x 2000), stained with 50% aqueous silver nitrate, immersed in a diluted developer solution (24 hours), rinsed and sectioned in two pieces with a low speed saw (Isomet). Dye penetration (Score 0-4) was determined separately at the occlusal enamel margin and cementoenamel junction. The volumetric polymerization shrinkage of materials was determined with the apparatus of Watts and Cash (Watts Cash, 1991) for 300 seconds. Polymerization shrinkage results were as follows: Filtek Flow (3.5% +/- 0.1) > Admira (2.1% +/- 0.1) = Ariston AT (2.3% +/- 0.1) > Filtek Z-250 (1.8% +/- 0.1) (One-way Anova, post hoc Bonferroni test at p = 0.05 level). No statistical difference was found at the enamel margins for any of the materials (Score 0-1). At the cemento-enamel junction, all test groups showed significantly higher microleakage when compared to the enamel margins (Kruskal-Wallis test, Mann-Whitney U). Dye penetration results at dentin were as follows: Filtek Flow + Filtek Z-250 = Admira < Ariston AT = Filtek Z-250. microleakage than the ion-releasing and hybrid composites lined only with bonding agent at the cementoenamel junction in Class II cavities.
authors.affiliation: Department of Operative Dentistry, Faculty of Dentistry, Yeditepe University, Istanbul, Turkey. arzucivelek@hotmail.com
authors.forename: Arzu
authors.initials: A
authors.lastname: Civelek
authors.forename: M
authors.initials: M
authors.lastname: Ersoy
authors.forename: E
authors.initials: E
authors.lastname: L'Hotelier
authors.forename: M
authors.initials: M
authors.lastname: Soyman
authors.forename: Esra Can
authors.initials: EC
authors.lastname: Say
mesh_terms: D000180:Acrylic Resins; D017438:Bisphenol A-Glycidyl Methacrylate; D003188:Composite Resins / Q000528:radiation effects*; D003737:Dental Cavity Preparation; D003743:Dental Enamel; D003763:Dental Leakage; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000379:methods*; D003804:Dentin; D017220:Dentin-Bonding Agents; D006801:Humans; D008027:Light; D008689:Methacrylates; D008963:Molar; D019279:Resin Cements; D012833:Siloxanes
chemical_list: D000180:Acrylic Resins; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C467913:Filtek Flow; C444701:Filtek Z250; D008689:Methacrylates; D019279:Resin Cements; D012833:Siloxanes; C479084:admira; C479085:admira bond; C479083:ariston AT; C454691:ariston liner; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate