The effect of selected variables on the retention of irreversible hydrocolloid impression material.

Aim: The aim of this study was to investigate the effect selected variables have on the retention of irreversible hydrocolloid impression material in an impression tray.

Methods And Materials: To simulate custom impression trays, acrylic resin plates were fabricated from autopolymerizing tray resin and visible light-activated composite resin (VLC). A total of 240 plates of each material were fabricated.

Some variables influencing the bond strength between PMMA and a silicone denture lining material.

Purpose: The purpose of the present study was to investigate the effect of roughening the denture base surface on the tensile and shear bond strengths of a poly(dimethylsiloxane) resilient lining material (Molloplast-B) bonded to a heat-cured acrylic resin denture base material. These measured bond strengths were compared to those obtained by packing the soft lining material against poly(methyl methacrylate) (PMMA) denture base acrylic resin dough.

Materials And Methods: Three groups of 10 specimens each were constructed for both tensile and shear tests.