Comparative study of thermo-mechanical and thermogravimetric characterization of hybrid dental restorative composite materials

Abstract

The purpose of the study is to create resin-based micro-nano particulates-filled dental restorative composite materials and investigate the influence of variable nano-hydroxyapatite filler concentration on their thermo-mechanical and thermogravimetric properties. Two series were created by combining silane treated nano-hydroxyapatite filler particles (wt.% of 0, 2, 4, 6, and 8) with foreign ceramic particles (alumina and titanium oxide). Each series consists of five compositions. For each dental composition, the amount of foreign ceramics (20 wt.%) remained constant. The dental composite samples were polymerized for 30 s on each side using a blue LED light. Thermo-mechanical and thermogravimetric analysis was performed at various temperatures range. At preliminary temperatures (30–40°C), the hybrid nano-hydroxyapatite-TiO2 dental composite filled with 8 wt.% nano-hydroxyapatite exhibited storage modulus (about 90 MPa) whereas nano-hydroxyapatite-Al2O3 dental composite filled with 8 wt.% nano-hydroxyapatite exhibited storage modulus (about 260 MPa). Themal stability of nano-hydroxyapatite-Al2O3 and nano-hydroxyapatite-TiO2 dental composite was 99.90% and 99.82% at 90°C, respectively. The glass phase, glass transition phase, and rubbery phase were observed at various temperatures. From the results, it revealed that Al2O3-nano-hydroxyapatite filled dental composite was observed significant than TiO2–nano-hydroxyapatite filled dental composite.