title: Influence of phosphoric acid etching on microleakage of a self-etch adhesive and a self-adhering composite.
abstract: BACKGROUND
  The aim of this study was to evaluate the influence of preliminary phosphoric acid etching on the microleakage of a self-adhering flowable composite and a self-etch adhesive used in combination with the proprietary flowable composite.
  
  
  METHODS
  Standard Class V cavities were prepared on the buccal side of 20 extracted sound human molars. Specimens were randomly divided into five groups: (1) Gel Etchant/Optibond FL/Premise Flowable; (2) Vertise Flow; (3) Optibond XTR/Premise Flowable; (4) Gel Etchant/Vertise Flow; and (5) Gel Etchant/Optibond XTR/Premise Flowable (Kerr). The interfacial sealing ability of the materials was evaluated by scoring the depth of silver nitrate penetration and through scanning electron microscopy observations. Differences in leakage at either the enamel or the dentine interface were evaluated for statistical significance (Kruskal-Wallis ANOVA, Mann-Whitney U test, p < 0.05).
  
  
  RESULTS
  At the enamel interface, no significant differences were found among the materials. On dentine, Gel Etchant/Vertise Flow had the highest leakage scores and the difference was statistically significant (p < 0.05).
  
  
  CONCLUSIONS
  The early sealing ability of the self-adhering flowable composite and the self-etch adhesive in Class V restorations did not significantly benefit from selective enamel etching. Preliminary phosphoric acid etching of dentine negatively affected the quality of the seal when using the adhesive-free flowable composite.
authors.affiliation: Department of Dental Materials and Fixed Prosthodontics, Tuscany School of Dental Medicine, University of Florence and Siena, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Rengo
authors.forename: C
authors.initials: C
authors.lastname: Goracci
authors.forename: J
authors.initials: J
authors.lastname: Juloski
authors.forename: N
authors.initials: N
authors.lastname: Chieffi
authors.forename: A
authors.initials: A
authors.lastname: Giovannetti
authors.forename: A
authors.initials: A
authors.lastname: Vichi
authors.forename: M
authors.initials: M
authors.lastname: Ferrari
mesh_terms: D000134:Acid Etching, Dental; D003188:Composite Resins; D001840:Dental Bonding; D003743:Dental Enamel; D003763:Dental Leakage; D003793:Dental Restoration, Permanent / Q000145:classification / Q000379:methods*; D003804:Dentin; D006801:Humans; D008422:Materials Testing; D010756:Phosphoric Acids; D019279:Resin Cements; D018709:Statistics, Nonparametric; D019237:Tooth Cervix
chemical_list: D003188:Composite Resins; D010756:Phosphoric Acids; D019279:Resin Cements