Effect of Metal Fillers on Thermal Conductivity of Acrylic Base Complete Dentures

Dental material research has entailed creating new and improved materials for prosthetic and restorative purposes, as well as modifying current materials. A number of studies on the use of fillers for strengthening denture base resin demonstrated an important enhancement in its physical properties. The purpose of this study is to prepare heat-curing PMMA denture base composites containing micron-size silver, alumina, and Chrome cobalt alloy filler particles separated with three different percentages in PMMA composite and investigate their thermal conductivity. In the dental application, improving the PMMA denture base can be provided by using several different filler loadings. Materials and Method: This research explored the preparation of PMMA denture base materials enhanced with silver, alumina, and chrome cobalt alloy fillers. PMMA powder was combined with these metal fillers at varying concentrations (1%, 2%, and 3% by weight) and mixed with a liquid component at a 2.5:1 ratio. The mixture achieved a workable dough stage in about 15 minutes and was then molded. Curing occurred in a water bath at 78 °C for 90 minutes to ensure complete polymerization. Twelve acrylic specimens were created, each measuring 60 mm by 40 mm, with thicknesses from 0.4 mm to 5.0 mm, following ISO 1567:2001 standards for denture base preparation. This study aims to optimize the mechanical properties of denture bases through the incorporation of metal fillers. Result: The difference in thermal conductivity among the three concentrations of Ag, Al2O3, and CoCr is slight. The control group exhibited significantly lower average thermal conductivity values compared to the experimental groups. The thermal conductivity value of (Ag) was statistically significantly higher than that of (Al₂ O₃) and (CoCr). Keywords: Metal fillers, Polymethyl Methacrylate (PMMA), thermal conductivity, silver nanoparticles, nanocomposites.