title: Flowable composites as "filled adhesives:" a microleakage study.
abstract: OBJECTIVE
  The purpose of this in vitro study was to investigate the microleakage at dentin margins of a flowable resin composite associated with an adhesive, either light cured separately or co-cured, in Class V cavities.
  
  
  METHODS
  Twenty four recently extracted human molars were prepared with standardized box-shaped Class V cavities of 3.0 mm (mesial-distal), 2.0 mm (occlusal-gingival), and 2.0 mm depth with margins located on enamel and dentin/cementum on the buccal or lingual surfaces. The cavities were randomly assigned into three groups (n=8): Group I - Single Bond + Filtek Z250 (control); Group II - Single Bond + Filtek Flow (light cured separately) + Filtek Z250; and Group III - Single Bond + Filtek Flow co-cured (light cured simultaneously) + Filtek Z250. After being immersed in tap water for 24 h, the specimens were thermocycled (1000x, 5 degrees -55 degrees C, 30 sec dwell time) and immersed in a 0.5% basic fuchsine solution for 24 h. The restorations were sectioned longitudinally and gingival margins were evaluated for microleakage using a 0-4 scale. Data were subjected to the Kruskal-Wallis test at p<0.05.
  
  
  RESULTS
  A statistically significant difference at p = 0.0044 between Groups 1 and 3 and Groups 2 and 3 was observed. Although Group 2 performed slightly better than Group 1, no significant difference was observed.
  
  
  CONCLUSIONS
  The use of a flowable resin composite cured simultaneously with an adhesive yielded the worst results in this study. As no statistical differences were seen between Groups 1 and 2, the use of a flowable composite as a means of minimizing microleakage at dentin margins may be questioned.
authors.affiliation: Department of Operative Dentistry, Universidade Federal de Santa Catarina, Florianópolis, 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: Sylvio
authors.initials: S
authors.lastname: Monteiro
authors.forename: Luiz Narciso
authors.initials: LN
authors.lastname: Baratieri
authors.forename: Mauro Amaral
authors.initials: MA
authors.lastname: Caldeira de Andrada
mesh_terms: D000269:Adhesives / Q000528:radiation effects; D017438:Bisphenol A-Glycidyl Methacrylate / Q000528:radiation effects; D003188:Composite Resins / Q000528:radiation effects; D003763:Dental Leakage / Q000209:etiology* / Q000517:prevention & control; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000009:adverse effects* / Q000379:methods*; D017220:Dentin-Bonding Agents / Q000528:radiation effects; D004338:Drug Combinations; D006801:Humans; D008027:Light; D008963:Molar; D044367:Phase Transition; D011897:Random Allocation; D018709:Statistics, Nonparametric
chemical_list: D000269:Adhesives; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D004338:Drug Combinations; C467913:Filtek Flow; C444701:Filtek Z250; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate