Poster 5, Language: GermanNergiz, Ibrahim/Pfeiffer, PeterThe recommended bond strength for polymer-based crown and bridge veneering materials without macromechanical retention is at least 5 MPa (ISO 10477, amendment 1, 04-98). The purpose of this study was to evaluate the shear bond strength of veneering composite resins to the gold alloy using different bonding systems. Two commercial bonding systems [Kevloc (Kulzer), Rocatector Delta (ESPE)] were evaluated. Bonding was attempted with the opaque resin provided by each system. Dentacolor, Artglass (Kulzer) and Sinfony (ESPE) were used as veenering composite resins. Samples with mechanical retention acted as a control group. Nine specimens were tested from each combination. Shear bond tests were performed after aging the disk samples (Au-Pt) by 5000 thermocycles (5 - 55 oC) and one week water storage at 37 oC. Data were analyzed by ANOVA at a significance level of 0.05. Shear bond strengths, exceeding 8 MPa, were achieved for all the bonding systems with corresponding veneering composite resins (control groups: 10 - 15 MPa). Mean shear bond strengths of the Kevloc system in combination with different composites (10 - 13 MPa) showed no significant differences to the Rocatector/Sinfony combination (10 MPa). Bond strength of nearly all combinations of products of different manufacturers (Dentacolor/Artglass/Rocatector and Sinfony/Kevloc) were close (with the exception of Sinfony/Kevloc) to the recommended clinical threshold value of 5 MPa for the resin/alloy bond (ISO). Strong, durable bonds can be achieved between the chemically conditioned (Kevloc, Rocatector Delta) gold alloy and the corresponding veneering composite resins, thus enhancing the usefulness of chemical bonds for resin-veneered crowns.