Influence of 2% chlorhexidine digluconate on bond strength of a glass-fibre post luted with resin or glass-ionomer based cement

J Dent. 2014 Jun;42(6):735-41. doi: 10.1016/j.jdent.2014.02.019. Epub 2014 Mar 5.

Abstract

Objectives: This study evaluated the influence of 2% chlorhexidine digluconate (CHX) on the bond strength (BS) of a glass-fibre post to the root canal, regarding the cements (dual-cured resin or resin-modified glass-ionomer cement), the root thirds and the time of storage.

Method: Eighty bovine roots were selected and endodontically treated, before being randomly assigned to the following groups according to the luting protocol: ARC (RelyX ARC); ARC+CHX; RL (RelyX Luting 2); and RL+CHX. After 24 h of luting, the roots were sliced to obtain 1 mm-thick slices. Half of each group was submitted to either 7-day or 6-month storage in artificial saliva (n=10). The specimens were subjected to push-out tests with a crosshead speed of 0.5 mm/min. The data were analysed with four-way ANOVA and Tukey's test (P≤0.05). The failure modes were analysed with a digital microscope (50× and 200×).

Results: ARC yielded a significantly higher BS compared to RL (P<0.001). Despite CHX exerted a significant effect; it depends on the interaction with the luting cement and time (P<0.001). Thus, CHX decreased the values of BS to those of ARC after 6 months (P<0.001). On the 7th day of storage, the ARC+CHX presented higher BS to the cervical and middle thirds compared to RL+CHX (P=0.012). Time solely was not a significant factor (P=0.081). Adhesive cement-dentine type and mixed failures were predominant modes for the ARC groups. For the RL groups, the main failures were adhesive cement-post and mixed modes.

Conclusions: Glass-fibre posts luted with RelyX ARC dual-cure resin cement exhibited higher BS than those luted with RelyX Luting 2 resin-modified glass-ionomer cement. Furthermore, CHX was not effective to improve the BS and negatively affected the BS of RelyX ARC after 6 months of storage.

Clinical significance: The use of chlorhexidine solution seems not to improve the bond strength of fibre posts to root canals, disregarding the composition of the luting cement.

Keywords: Bond strength; Chlorhexidine; Dual-cure resin cement; Resin-modified glass-ionomer cement; Root canal.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bisphenol A-Glycidyl Methacrylate / chemistry
  • Cattle
  • Chlorhexidine / analogs & derivatives*
  • Chlorhexidine / chemistry
  • Composite Resins / chemistry
  • Dental Bonding*
  • Dental Materials / chemistry*
  • Dental Pulp Cavity / ultrastructure*
  • Dentin / ultrastructure
  • Enzyme Inhibitors / chemistry*
  • Glass / chemistry*
  • Glass Ionomer Cements / chemistry*
  • Materials Testing
  • Polyethylene Glycols / chemistry
  • Polymethacrylic Acids / chemistry
  • Post and Core Technique / instrumentation*
  • Random Allocation
  • Resin Cements / chemistry*
  • Root Canal Preparation / methods
  • Saliva, Artificial / chemistry
  • Self-Curing of Dental Resins
  • Stress, Mechanical
  • Surface Properties
  • Time Factors
  • Tooth Apex / ultrastructure

Substances

  • Composite Resins
  • Dental Materials
  • Enzyme Inhibitors
  • Glass Ionomer Cements
  • Polymethacrylic Acids
  • RelyX ARC
  • Resin Cements
  • Saliva, Artificial
  • Vitremer
  • fiberglass
  • Polyethylene Glycols
  • Bisphenol A-Glycidyl Methacrylate
  • chlorhexidine gluconate
  • Chlorhexidine