Effects of pretreatment and thermocycling on bond strength of resin core materials to various fiber-reinforced composite posts.
OBJECTIVE
To evaluate the effects of pretreatment (silanization) and thermocycling on bond strengths of 2 core materials to 3 different types of fiber posts.


METHODS
Bond strengths of prefabricated glass (group 1), quartz (group 2), and individually formed glass fiber posts (group 3) to either a flowable or a highly viscous composite resin core material were measured using a push-out design. All posts were investigated with or without the application of a silane. Half of the specimens were stored in distilled water for 28 days, and were subsequently subjected to thermocycling (5000 cycles, 5 to 55 degrees C), whereas the other half was investigated after 24-h water storage.


RESULTS
Bond strengths were significantly affected by thermocycling (p < 0.0005), post type (p < 0.0005), and pretreatment (p < 0.0005), but not by the core material (p = 0.149; four-way ANOVA). Posts of group 3 demonstrated significantly higher bond strengths than all other posts, even after thermocycling (p < 0.05; Tukey-B).


CONCLUSIONS
While silanization had negligible effects, thermocycling drastically reduced bond strengths regardless of pretreatment, post type, or core material. The higher bond strengths between the group 3 posts and the flowable composite resin core material might result in improved stability of the core for postendodontic restorations.
Bitter
Kerstin
K
Department of Operative Dentistry and Periodontology, University School of Dental Medicine, CharitéCentrum 3, Charité-Universitätsmedizin Berlin, Berlin, Germany. Kerstin.bitter@charite.de
Neumann
Konrad
K
Kielbassa
Andrej M
AM
D000180:Acrylic Resins / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D017267:Dental Prosthesis Design; D004853:Epoxy Resins / Q000737:chemistry; D005898:Glass / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D011176:Post and Core Technique / Q000295:instrumentation*; D011791:Quartz / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
D000180:Acrylic Resins; C489662:AdheSE cement; C029849:Clearfil Bonding Agent; C469237:Clearfil Core; D003188:Composite Resins; D003738:Dental Cements; D003764:Dental Materials; D004853:Epoxy Resins; D008689:Methacrylates; C076808:Monobond S; C509715:MultiCore Flow; D019279:Resin Cements; D012821:Silanes; C496140:everStick; C009753:fiberglass; C111840:flowable hybrid composite; D014867:Water; D011791:Quartz