The efficacy of different sealer removal protocols on bonding of self-etching adhesives to AH plus-contaminated dentin.
BACKGROUND
Smearing of unset root canal sealers over the pulp chamber dentin may adversely affect bonding of self-etching adhesives and jeopardize their coronal sealing potential. This study examined the influence of different sealer removal protocols on the microtensile bond strengths of two self-etching adhesives to AH Plus-contaminated dentin.


METHODS
Coronal dentin surfaces were prepared from extracted human third molars. In the positive control groups, these surfaces were not contaminated with sealer and were bonded with Clearfil SE Bond or Clearfil Tri-S Bond. For the experimental groups, dentin surfaces were contaminated with AH Plus and wiped with either dry cotton pellets, cotton pellets saturated with ethanol, or cotton pellets saturated with Endosolv R followed by rinsing the dissolved sealer with water prior to bonding with the two adhesives. Bonded specimens were sectioned into resin-dentin beams for microtensile bond strength evaluation. Additional specimens were prepared for transmission electron microscopy to examine the ultrastructure and nanoleakage within the hybrid layers.


RESULTS
For both adhesives, microtensile bond strengths significantly declined when the sealer was removed with dry cotton pellets or cotton pellets saturated with ethanol. Only the Endosolv R/water sealer removal protocol restored tensile bond strengths to those of the uncontaminated positive controls without adversely affecting hybrid layer formation in intact dentin or increasing nanoleakage within the resin-dentin interfaces.


CONCLUSIONS
The Endosolv R sealer removal protocol appears to be effective in preventing the deterioration of bond strengths of the two self-etching adhesives to AH Plus-contaminated dentin and warrants further clinical investigation.
Department of Endodontics, School of Dentistry, Medical College of Georgia, Augusta, GA 30912-1129, USA.
Steven
S
Roberts
Jong Ryul
JR
Kim
Li-sha
LS
Gu
Young Kyung
YK
Kim
Quinn M
QM
Mitchell
David H
DH
Pashley
Franklin R
FR
Tay
D001840:Dental Bonding; D017005:Dental Debonding / Q000379:methods*; D003799:Dental Stress Analysis; D003804:Dentin; D017220:Dentin-Bonding Agents; D004853:Epoxy Resins; D000431:Ethanol; D005559:Formamides; D006801:Humans; D008422:Materials Testing; D046529:Microscopy, Electron, Transmission; D008964:Molar, Third; D019279:Resin Cements; D012387:Root Canal Filling Materials; D012997:Solvents; D013718:Tensile Strength
C438313:Clearfil SE Bond; C515604:Clearfil Tri-S Bond; D017220:Dentin-Bonding Agents; C473452:Endosolv R; D004853:Epoxy Resins; D005559:Formamides; D019279:Resin Cements; D012387:Root Canal Filling Materials; D012997:Solvents; C534916:epoxy resin-based root canal sealer; D000431:Ethanol