Bonding strategies to pulp chamber dentin treated with different endodontic irrigants: microshear bond strength testing and SEM analysis.
OBJECTIVE
To evaluate the effect of 6 irrigant regimens on the microshear bond strength of different adhesives to pulp chamber dentin and to determine their interfacial morphology by SEM.


METHODS
Forty-three human molars were split into halves and ground to provide flat pulp chamber dentin. Eighty-five halves were used. The specimens were assigned to 6 groups according to the irrigant regimen used. Group I (n=10) was irrigated with distilled water (control). The remaining 5 groups (n=15 each) were irrigated with 5.25% NaOCl followed by either 5.25% NaOCl, 17% EDTA, benzalkonium chloride (Tubilcid Plus) or MTAD (Biopure), either rinsed or not. Irrigated specimens were bonded using Clearfil S3 Bond or Adper Single Bond 2, which was employed with or without etching. Resin composite cylinders were bonded using tygon tubes for microshear bond strength testing. Data were analyzed using two-way ANOVA followed by Tukey's post-hoc test. Representative specimens of each group were prepared from 17 further molars for interfacial SEM examination.


RESULTS
The different irrigant regimens used did not significantly alter the microshear bond strength values using either of the bonding systems, except NaOCl, which significantly reduced the microshear bond strength values with Adper Single Bond 2. Bonding irrigated specimens directly using the Adper Single Bond 2 without prior etching provided significantly reduced values.


CONCLUSIONS
The irrigant regimens examined could be used safely prior to bonding except for the NaOCl, which should be negated if it is to be followed by Adper Single Bond 2, and the etching step cannot be omitted if an etch-and-rinse adhesive system is the adhesive of choice.
Faculty of Oral and Dental Medicine Cairo University, Dept. of Operative Dentistry, Manial, Cairo, Egypt.
Elham M
EM
Fawzi
Dina W
DW
Elkassas
Angie G
AG
Ghoneim
D000134:Acid Etching, Dental / Q000379:methods*; D017438:Bisphenol A-Glycidyl Methacrylate; D001840:Dental Bonding; D003786:Dental Pulp Cavity; D003799:Dental Stress Analysis; D003804:Dentin / Q000648:ultrastructure; D017220:Dentin-Bonding Agents; D006801:Humans; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements; D012388:Root Canal Irrigants / Q000737:chemistry; D033081:Shear Strength
C505694:Clearfil S3 Bond; D017220:Dentin-Bonding Agents; D019279:Resin Cements; D012388:Root Canal Irrigants; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate