A Comparative Study of the Effectiveness of Metal Surface Treatment in Controlling Microleakage of Two Different Metal and Acrylic Resin Interface

Microleakage at the junction between the metal alloy and acrylic resin in a removable partial denture may result in discoloration, fluid percolation, and acrylic resin deterioration and Failure of a removable partial denture. Dye penetration test was conducted on eighty specimens each of Nickel-Chromium/Cobalt-Chromium metal-Heat cure acrylic resin. Samples were randomly divided into eight groups (n=10) & adapted with base plate wax and they were invested. Groups were Sandblasted, Tin plated and silane coated individually and in their various combinations and were then packed with clear heat cure acrylic resin and processed over the surface treated side of the metal. All specimens were immersed in distilled water for 24 hours followed by thermocycling for 3000 cycles before immersion in dye for 24hrs. Counting of the grids which exhibited dye penetration allowed the assessment of extent of microleakage. The mean values of the grids that exhibited dye penetration in this group for Nickel-Chromium and Cobalt-Chromium alloys are 3.3000±2.584 and 3.6000±2.6331. microleakage values for both the metals were different for different combinations.