Comparative evaluation of tensile bond strength of denture base resins to surface pretreated cobalt chromium base metal alloys--an in vitro study.

This study was undertaken to evaluate the tensile bond strength of acrylic resins to surface pretreated Cobalt-chromium base metal alloy. A total of 60 tensile bar specimens were prepared. One half of the bar was cast in cobalt-chromium alloy and the other half made of denture base resins attached to the alloy following surface pretreatment. Two denture base resins and five surface pre-treatments were used which included sandblasting, acid etching, use of metal adhesive primers and the combination of the above mentioned modes. Gradual axial loads were applied on the tensile bar specimen mounted on a Hounsfield tensometer till bond failure was evident. Statistical evaluation was done using Mann-Whitney U test. The study results indicate that the bond strength in those specimens wherein a combination of sandblasting, acid etching and priming was done as surface pretreatment, showed the maximum values as compared to the other groups.