title: Effect of chlorhexidine application on the long-term shear bond strength to dentin of a resin-modified glass ionomer.
abstract: OBJECTIVE
  The aim of this study was to investigate the effect of chlorhexidine digluconate (CHX) application on the shear bond strength (SBS) of a resin-modified glass ionomer cement (RMGIC) to polyalkenoic acid-preconditioned dentin after 24 hours, six months, and 12 months of water storage at 37°C.
  
  
  METHODS
  Cylindrical molds, placed on flat, polyalkenoic acid (Cavity Conditioner® [GC]) preconditioned dentin surfaces of 90 human teeth embedded in resin, were filled with Fuji II LC® (GC), a RMGIC, with (n=45) or without (n=45) the prior application of a 0.05% CHX solution. Within each group, SBS was determined after 24 hours (n=15), six months (n=15), and 12 months (n=15) of storage in water at 37°C. The results were analyzed with two-way analysis of variance followed by Tukey multiple means comparisons (p<0.05). The type of bond failure (adhesive/cohesive/mixed) was noted and the results were analyzed with chi-square test (p<0.05).
  
  
  RESULTS
  After 24 hours, the SBS of RMGIC was not significantly different with (9.0 ± 2.8 MPa) or without (8.3±0.6 MPa) the application of CHX. After six months, however, SBS increased significantly in the group without CHX (12.7±3.4 MPa) but remained unchanged in the CHX group (9.4±4.0 MPa). Similar results without CHX (12.6±3.8 MPa) and with CHX (9.5±3.2 MPa) were obtained after 12 months. No significant differences in the type of debonding were found between the various groups tested.
  
  
  CONCLUSIONS
  The application of 0.05% CHX after dentin preconditioning did not seem to have affected the 24-hour SBS of RMGIC. However, the six- and 12-month SBS was significantly lower for CHX-treated samples, possibly as a result of CHX interference with both the bonding mechanism and the maturation reaction of RMGIC.
authors.affiliation: Faculty of Dental Surgery, Paris Descartes University, and Dental Department, Hospital Albert Chenevier-Henri Mondor, APHP, Paris, France. elisabethdursun@gmail.com
authors.forename: E
authors.initials: E
authors.lastname: Dursun
authors.forename: S
authors.initials: S
authors.lastname: Le Goff
authors.forename: D N
authors.initials: DN
authors.lastname: Ruse
authors.forename: J P
authors.initials: JP
authors.lastname: Attal
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000891:Anti-Infective Agents, Local / Q000737:chemistry*; D002710:Chlorhexidine / Q000031:analogs & derivatives* / Q000737:chemistry; D001840:Dental Bonding; D003804:Dentin / Q000648:ultrastructure*; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D019279:Resin Cements / Q000737:chemistry*; D012117:Resins, Synthetic / Q000737:chemistry; D033081:Shear Strength; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D000891:Anti-Infective Agents, Local; C079765:Fuji II LC cement; D005899:Glass Ionomer Cements; D019279:Resin Cements; D012117:Resins, Synthetic; D014867:Water; C006903:carbopol 940; C010882:chlorhexidine gluconate; D002710:Chlorhexidine