Bond strength between fibre posts and composite resin cores: effect of post surface silanization.
OBJECTIVE
To evaluate the tensile bond strength between two different composite resin cores and (Clearfil Core, MultiCore Flow) and fibre posts (DT Light Post), with and without silanization of the post surface.


METHODS
Forty fibre posts were shortened to a length of 15 mm. Specimens were then produced by covering the upper 3 mm of the posts with standardized composite core build-ups. The bonding surfaces of twenty posts were treated with silane coupling agent (Monobond-S). Four experimental groups were formed: G1: Clearfil Core; G2: Monobond-S + Clearfil Core; G3: MultiCore Flow; G4: Monobond-S + MultiCore Flow. Each post was positioned upright in a post centric device with moulds to ensure standardized shapes of the abutments. After tensile bond strength testing, the type of failure at the interface was determined. The results obtained were compared using an unpaired sample t-test.


RESULTS
The mean tensile bond strengths and standard deviations were [MPa] 10.08 +/- 0.92 for Clearfil Core, 10.47 +/- 1.05 for Clearfil Core + silane; 6.65 +/- 0.79 for MultiCore Flow and 6.91 +/- 0.83 for MultiCore Flow + silane. Statistical analysis revealed that Clearfil Core achieved significantly higher bond strengths than MultiCore Flow (P < 0.0001). Post silanization had no significant effect. All tested specimens had an adhesive failure mode.


CONCLUSIONS
Type of composite had a significant effect on tensile bond strength. Silanization of fibre post surfaces had no effect on core retention.
Wrbas
K T
KT
Department of Operative Dentistry and Periodontology, University School and Dental Hospital, Albert-Ludwigs-University Freiburg, Freiburg i Br, Germany. wrbas@uniklinik-freiburg.de
Schirrmeister
J F
JF
Altenburger
M J
MJ
Agrafioti
A
A
Hellwig
E
E
D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D019232:Dental Restoration Failure; D004853:Epoxy Resins / 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; D013718:Tensile Strength
C469237:Clearfil Core; D003188:Composite Resins; D003738:Dental Cements; D004853:Epoxy Resins; C481260:Lightpost; D008689:Methacrylates; C076808:Monobond S; C509715:MultiCore Flow; D019279:Resin Cements; D012821:Silanes; D011791:Quartz