title: Effects of chlorhexidine-containing adhesives on the durability of resin-dentine interfaces.
abstract: OBJECTIVE
  This study evaluated the effect of addition of diacetate CHX in different concentrations into two simplified etch-and-rinse (ER) adhesive systems (XP Bond [XP] and Ambar {AM}) on the ultimate tensile strength (UTS), degree of conversion (DC), 60-day cumulative water sorption (WS), solubility (SO) and CHX release (CR) as well as the immediate (IM) and 1-year (1Y) resin-dentine bond strength (μTBS) and nanoleakage (NL).
  
  
  METHODS
  Ten experimental adhesive systems were formulated according to the addition of CHX diacetate (0 [control], 0.01, 0.05, 0.1 and 0.2%) in the two ER. For UTS and DC, specimens were constructed and tested after 24h. For WS, SO and CR, after specimens build-up, they were stored in water and the properties measured after 60 days. The occlusal enamel of fifty molars was removed and the adhesives were applied in dentine surface after 37% phosphoric acid etching. After composite resin build-ups, specimens were longitudinally sectioned to obtain resin-dentine bonded sticks (0.8mm(2)). Specimens were tested in tension at 0.5mm/min in the IM or 1Y. For NL, 2 bonded sticks from each tooth were prepared and analyzed under SEM. The data were submitted to appropriate statistical analysis (α=0.05).
  
  
  RESULTS
  The addition of CHX did not influence UTS, DC, WS and SO (p<0.05). Higher CR was observed in adhesives with higher concentration of CHX (p<0.05). After 1Y, significant reductions of μTBS and increases of NL were observed in the control groups (p<0.05). Reductions of μTBS and increase of NL over time were not observed (AM) for CHX-containing adhesives or it was less pronounced than the control (XP) regardless of the CHX concentration.
  
  
  CONCLUSIONS
  The addition of CHX diacetate in concentrations until 0.2% in the simplified ER adhesive systems may be an alternative to increase the long-term stability of resin-dentine interfaces, without jeopardizing the adhesives' mechanical properties evaluated.
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Brazil; Department of Restorative, Dentistry, Center of High Education of Campos Gerais, Ponta Grossa, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Stanislawczuk
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Brazil.
authors.forename: Fabiane
authors.initials: F
authors.lastname: Pereira
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Brazil; Department of Restorative, Dentistry, Center of High Education of Campos Gerais, Ponta Grossa, Brazil.
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Muñoz
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Brazil; Department of Restorative, Dentistry, Center of High Education of Campos Gerais, Ponta Grossa, Brazil.
authors.forename: Issis
authors.initials: I
authors.lastname: Luque
authors.affiliation: Department of Pharmaceutical Sciences, State University of Ponta Grossa, Ponta Grossa, Brazil.
authors.forename: Paulo Vitor
authors.initials: PV
authors.lastname: Farago
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Brazil.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Reis
authors.affiliation: Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Brazil. Electronic address: aloguercio@hotmail.com.
authors.forename: Alessandro D
authors.initials: AD
authors.lastname: Loguercio
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000293:Adolescent; D000328:Adult; D002710:Chlorhexidine / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003763:Dental Leakage / Q000145:classification; D003764:Dental Materials / Q000737:chemistry; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D058105:Polymerization; D011140:Polyurethanes / Q000737:chemistry; D012995:Solubility; D013314:Stress, Mechanical; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D013718:Tensile Strength; D013997:Time Factors; D014867:Water / Q000737:chemistry; D055815:Young Adult
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D008689:Methacrylates; D011140:Polyurethanes; D013501:Surface-Active Agents; C532387:XP-Bond; D014867:Water; C029824:urethane dimethacrylate luting resin; C069749:methacryloyloxydecyl dihydrogen phosphate; D002710:Chlorhexidine
keywords: Adhesives systems; Chlorhexidine; Durability; Long-term; Microtensile bond strength; Nanoleakege