1000 Effect of Root-Canal Pretreatment on Fiber Post Bond Strength

Friday, March 23, 2012: 3:30 p.m. - 4:45 p.m.
Presentation Type: Poster Session
B.C. YAMAN, Operative Dentistry, University of Istanbul, Istanbul, Turkey, F. OZER, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, B. KARABUCAK, Department of Endodontics, University of Pennsylvania, Philadelphia, PA, F. KORAY, Faculty of Dentistry, University of Istanbul -, Capa Istanbul, Turkey, and M.B. BLATZ, Robert Schattner Center, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA
Objectives:

To evaluate bond strength of a self-adhesive resin cement to a quartz-fiber post and to dentin after different root canal irrigantion protocols and with or without bonding agent application.

Methods:

Roots of thirty-six human premolars were endodontically treated and divided into six groups. All roots were drilled for post spaces in a standardized manner. Before post cementation, root canals were pretreated with one of three irrigation protocols (5.25% NaOCl, 18% EDTA, 2% Chlorhexidine) and with or without a dual-cure adhesive bonding agent (Prime&Bond NT, Dentsply). Application procedures and groups (G) were: G1-5.25% NaOCl with (w/bonding) and without bonding agent application (w/o bonding), G2-18% EDTA→5.25% NaOCl w/o bonding and w/bonding agent, G3-18% EDTA→5.25% NaOCl→2% Chlorhexidine w/o bonding and w/bonding agent. Afterwards, quartz fiber posts (Unicore, Ultradent) were luted with self-adhesive resin cement (G-CEM, GC Corporation). The roots were then thermocycled for 2000 cycles between 5-55° C and cut into 1 mm thick dentin slabs. The bond strength of slabs was measured with an hourglass microtensile test method at a cross-head speed of 0.5 mm/minute. Failure modes were assessed with a stereomicroscope and data analyzed with two-way ANOVA and Tukey HSD test.

Results:

 

Bond Strength [MPa]±SD

Groups

w/o bonding

w/ bonding

G1

12.6±4.15a

19.1±3.42b

G2

10.8±1.92a

15.0±4.15ab

G3

12.6±2.52a

18.0±1.89b

 *Means with same letter are not significantly different

The different irrigation procedures did not influence bond strength of a quartz fiber post to root canal dentin (P>0.05). Bonding application did, in general, increase bond strength values. The groups with bonding agent application showed mainly adhesive failures between resin cement and post surface.

Conclusions:

 Dentin bonding agent application significantly increases bond strength of a self-adhesive resin cement to a fiber post and root canal dentin, independent of the root canal irrigation protocol.


Keywords: Cements, Dentin bonding agents, Endodontics and Fiber Posts