Synthesis and Characterization of Dental Nanocomposite Resins Filled with Different Clay Nanoparticles

Abstract

Nanotechnology comprises a promising approach towards the update of dental materials.The present study focuses on the reinforcement ofdental nanocomposite resins with diverse organomodified montmorillonite (OMMT) nanofillers. The aim is to investigate whether the presence of functional groups in the chemical structure of the nanoclay organic modifier may virtually influence the physicochemical and/or the mechanical attitude of the dental resin nanocomposites. The structure and morphology of the prepared materials were investigated by means of wide angle X-ray diffraction and scanning electron microscopy analysis. Fourier transform infrared spectroscopy was used to determine the variation of the degree of conversion over time. Measurements of polymerization shrinkage and mechanical properties were conducted with a linear variable displacement transducer apparatus and a dynamometer, respectively. All the obtained nanocomposites revealed intercalated structures and most of them had an extensive filler distribution into the polymer matrix. Polymerization kinetics werefound to be influenced by the variance of the clay organomodifier, whilenanoclays with vinyl groups considerably increased the degree of conversion. Polymerization shrinkage was almost limited up to 50% by incorporating nanoclays. The absence of reactive groups in the OMMT structure may retain setting contraction atlow levels. An enhancement of the flexural modulus was observed, mainly by using clay nanoparticles decorated with methacrylated groups, along with a decrease in the flexural strength at a high filler loading. The overall best performance was found for the nanocomposites with OMMTs containing double bonds. The significance of the current work relies on providing novel information about chemical interactions phenomena between nanofillers and the organic matrix towards the improvement of dental restorative materials.

Study of POSS on the Properties of Novel Inorganic Dental Composite Resin

“…However, some of its shortcomings such as poor strength, bad abrasion resistance, and large polymerization shrinkage are also exposed as the service time increases. The application of new nanofillers in dental resins has been widely studied to improve the mechanical and anti-caries properties [4][5][6].…”

Pit and fissure nanocomposite sealants reinforced with organically modified montmorillonite: A study of their mechanical properties, surface roughness and color stability

“…Based on a correlation between the emerged tendencies of flexural modulus and the differences in the chemical structures of the clay organomodifiers (Table 1), it is apparent that chemical interactions could play a key role towards the improvement of flexural modulus. Specifically, methacrylated groups located in the quaternary ammonium molecule of MMT-DMAODM are capable of forming covalent bonds with Bis-GMA/TEGDMA system through a polymerization reaction 42) , contributing to the highest stiffness of the corresponding nanocomposite. Furthermore, the significant augmentation of modulus due to Nanomer ® I.34MN nanoparticles could be attributed to their hydroxy-groups which might be involved in hydrogen bonging with ester groups of monomers.…”

Advanced characterization of surface-modified nanoparticles and nanofilled antibacterial dental adhesive resins

“…In addition, phase separation between nanoparticles and the polymeric matrix was not be observed for all nanoparticles and experimental materials investigated. According to Nikolaidis et al 49 the absence of phase separation in nanofilled dental biomaterials is a good indication of the successful functionalization of nanoparticles into current polymer compositions, and typically translates into experimental materials with superior physical, mechanical and biological properties.…”