Accelerated aging of adhesive-mediated fiber post-resin composite bonds: A modeling approach.
OBJECTIVE
Although fiber posts luted in root canals are not directly exposed to oral fluids, water storage is considered as in vitro accelerated aging test for bonded interfaces. The aim of the study was to evaluate the influence of accelerated water aging on fiber post-resin composite adhesion.


METHODS
Forty fiber posts (DT Light Post, RTD) were randomly divided into two main groups, according to the surface treatment performed. Group I: XPBond adhesive (Dentsply Caulk); Group II: sandblasting (Rocatec-Pre, 3M ESPE) and XPBond. Dual-cured resin cement (Calibra, Dentsply Caulk) and flowable composite (X-Flow, Dentsply Caulk) were applied on the posts to produce cylindrical specimens. The bond strength at the interface between post and cement/composite was measured with the microtensile test according to the non-trimming technique. Half of the sticks were tested immediately for bond strength, while in the other half testing was performed after 1 month of water storage at 37 degrees C. Post-cement/composite interfaces were evaluated under SEM prior and after water aging. Statistical analysis was performed using the Kruskal-Wallis ANOVA followed by Dunn's multiple range test (p<0.05).


RESULTS
Immediate bond strength was higher on sandblasted posts. After water aging the two post surface treatments resulted comparable in bond strength. Resin cement achieved higher bond strength to fiber posts than flowable composite. Water aging significantly reduced bond strength.


CONCLUSIONS
Sandblasting followed by adhesive coating may improve immediate post-resin bond strength in comparison to adhesive alone. However, fiber post-resin bond strength mediated by hydrophilic adhesive tends to decrease after water aging.
Radovic
Ivana
I
Clinic for Pediatric and Preventive Dentistry, Faculty of Dentistry, University of Belgrade, Dr. Subotica 11, Beograd 11000, Serbia. ivana.radovic@iritel.com
Monticelli
Francesca
F
Papacchini
Federica
F
Magni
Elisa
E
Cury
Alvaro Hafiz
AH
Vulicevic
Zoran R
ZR
Ferrari
Marco
M
D000180:Acrylic Resins / Q000737:chemistry*; D020906:Air Abrasion, Dental; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding / Q000379:methods*; D011140:Polyurethanes / Q000737:chemistry*; D011176:Post and Core Technique; D013499:Surface Properties; D013718:Tensile Strength; D013997:Time Factors
D000180:Acrylic Resins; C029012:Composite Dental Resin; D003188:Composite Resins; D011140:Polyurethanes