Effect of the activation mode of post adhesive cementation on push-out bond strength to root canal dentin.
OBJECTIVE
To evaluate the effect of the activation mode of adhesive cementation on push-out bond strength of fiber-reinforced resin posts to root canal dentin.


METHODS
Forty mandibular premolars were endodontically treated and randomly divided into 4 equal groups. In groups G-1, G-2, and G-3, Single Bond (3M Espe) was applied and light polymerized for 20 seconds; in group G-4, Scotchbond Multi-Purpose Plus (3M Espe) was used as an autopolymerized adhesive. The dual-cure resin cement Rely X ARC (3M Espe) was light polymerized in G-2 and G-3 but not in G-1 and G-4. The translucent post Light-Post (Bisco) was used in G-3 and the opaque post Aestheti-Plus (Bisco) in the other groups. The roots were sectioned in 3 parts (cervical, middle, apical); each slice was submitted to the push-out test at a crosshead speed of 0.5 mm/min. Data were analyzed by analysis of variance and Tukey test (a = .05).


RESULTS
Light polymerization of both the adhesive and resin cement in G-2 led to significantly higher bond strength than in G-1, where only the adhesive was light polymerized. No difference was found between G-2 (opaque post) and G-3 (translucent post). The autopolymerized adhesive showed the highest bond strength in all root regions. The middle and apical post/root regions had similar bond strength, but it was significantly lower than that in the cervical region (P <.001).


CONCLUSIONS
Bond strength to root dentin varied as a function of the activation mode of post adhesive cementation and post/root regions.
Boff
Luis Leonildo
LL
Federal University of Santa Catarina (UFSC), Florianópolis, Santa Catarina, Brazil. luisboff@uol.com.br
Grossi
Márcio Lima
ML
Prates
Luiz Henrique Maykot
LH
Burnett
Luiz Henrique
LH
Shinkai
Rosemary Sadami Arai
RS
D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry* / Q000528:radiation effects; D003738:Dental Cements / Q000737:chemistry* / Q000528:radiation effects; D006801:Humans; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000528:radiation effects; D011109:Polymethacrylic Acids / Q000737:chemistry* / Q000528:radiation effects; D011176:Post and Core Technique / Q000295:instrumentation*; D019279:Resin Cements / Q000737:chemistry*
D003738:Dental Cements; D011109:Polymethacrylic Acids; C462240:RelyX ARC; D019279:Resin Cements; C425844:Scotchbond Multi-Purpose Plus; C115612:single bond; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate