Durability of the bond between resin composite cores and prefabricated posts.
OBJECTIVE
This study evaluated the effect of post surface treatment and of storage condition on the bond between resin composite cores (Clearfil Core) and posts of titanium alloy (Fysika), silica-zircon fiber reinforced epoxy resin (SiliciumPost), and zirconia (CosmoPost).


METHODS
In the experimental groups, the coronal part of each post received sandblasting or tribochemical silicate-coating (CoJet) treatment. The coronal part of each post was embedded in a cylinder of resin composite core material with the aid of a fixation apparatus. After 15 min, the specimen was freed from the mold and stored in de-ionized water. The axial tensile strength (ATS) of posts was determined in a Universal Testing Machine when extracting the posts from the resin composite cores after: 1) 14 d water storage at 37°C, 2) 14 d water storage at 37°C followed by thermal cycling (6,000 cycles between 5°C and 55°C), or 3) 1 year water storage at 37°C. The results were statistically analyzed by three-way factorial ANOVA and Newman-Keuls' multiple range test.


RESULTS
The ATS values were generally higher for Fysika posts and SiliciumPost posts than for CosmoPost posts. Surface treatment effectively improved the ATS values of Fysika posts and SiliciumPost posts, but not those of CosmoPost posts. Thermal cycling or long-term water storage had only minimal effect on the ATS values of the posts.


CONCLUSIONS
Bonding of resin composite cores to the posts depended more on the material of the post and the surface treatment of posts than on the storage condition.
Department of Oral Rehabilitation, School of Dentistry, University of Copenhagen, Copenhagen, Denmark.
Alireza
A
Sahafi
Anne
A
Peutzfeldt
D000497:Alloys; D003188:Composite Resins / Q000737:chemistry*; D003722:Dental Alloys / Q000737:chemistry; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods; D003764:Dental Materials / Q000737:chemistry*; D017267:Dental Prosthesis Design; D003799:Dental Stress Analysis / Q000295:instrumentation; D004853:Epoxy Resins / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D011176:Post and Core Technique / Q000295:instrumentation*; D019279:Resin Cements / Q000737:chemistry; D017640:Silicates / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors; D014025:Titanium / Q000737:chemistry; D014867:Water / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry
D000497:Alloys; C469237:Clearfil Core; D003188:Composite Resins; D003722:Dental Alloys; D003764:Dental Materials; D004853:Epoxy Resins; D019279:Resin Cements; D017640:Silicates; D014867:Water; C031462:titanium alloy (TiAl6V4); C003784:zircon; D012822:Silicon Dioxide; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide