Reinforcement of a PMMA resin for interim fixed prostheses with silica nanoparticles

Marianthi Topouzi; Eleana Kontonasaki; Dimitrios Bikiaris; Lambrini Papadopoulou; Konstantinos M Paraskevopoulos; Petros Koidis

doi:10.1016/j.jmbbm.2017.01.013

Reinforcement of a PMMA resin for interim fixed prostheses with silica nanoparticles

J Mech Behav Biomed Mater. 2017 May:69:213-222. doi: 10.1016/j.jmbbm.2017.01.013. Epub 2017 Jan 9.

Authors

Marianthi Topouzi¹, Eleana Kontonasaki¹, Dimitrios Bikiaris², Lambrini Papadopoulou³, Konstantinos M Paraskevopoulos⁴, Petros Koidis⁵

Affiliations

¹ School of Health Sciences, Department of Dentistry, Section of Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece.
² Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece.
³ Department of Geology, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece.
⁴ Department of Physics, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece.
⁵ School of Health Sciences, Department of Dentistry, Section of Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece. Electronic address: pkoidis@dent.auth.gr.

PMID: 28088693
DOI: 10.1016/j.jmbbm.2017.01.013

Abstract

Purpose: Fractures in long span provisional/interim restorations are a common complication. Adequate fracture toughness is necessary to resist occlusal forces and crack propagation, so these restorations should be constructed with materials of improved mechanical properties. The aim of this study was to investigate the possible reinforcement of neat silica nanoparticles and trietoxyvinylsilane-modified silica nanoparticles in a PMMA resin for fixed interim restorations.

Materials and methods: Composite PMMA-Silica nanoparticles powders were mixed with PMMA liquid and compact bar shaped specimens were fabricated according to the British standard BS EN ISO 127337:2005. The single-edge notched method was used to evaluate fracture toughness (three-point bending test), while the dynamic thermomechanical properties (Storage Modulus, Loss Modulus, tanδ) of a series of nanocomposites with different amounts of nanoparticles (0.25%, 0.50%, 0.75%, 1% w.t.) were evaluated. Statistical analysis was performed and the statistically significant level was set to p<0.05.

Results: The fracture toughness of all experimental composites was remarkably higher compared to control. There was a tendency to decrease of fracture toughness, by increasing the concentration of the filler. No statistically significant differences were detected among the modified/unmodified silica nanoparticles. Dynamic mechanical properties were also affected. By increasing the silica nanoparticles content an increase in Storage Modulus was recorded, while Glass Transition Temperature was shifted at higher temperatures.

Conclusions: Under the limitations of this in-vitro study, it can be suggested that both neat silica nanoparticles and trietoxyvinylsilane-modified silica nanoparticles, especially at low concentrations, may enhance the overall performance of fixed interim prostheses, as can effectively increase the fracture toughness, the elastic modulus and the Glass Transition Temperature of PMMA resins used in fixed provisional restorations.

Keywords: Dental fixed interim prostheses; Fracture toughness; Nanonocomposites; Poly(methyl methacrylate)-PMMA; Silica nanoparticles; Viscoelastic properties.

MeSH terms

Composite Resins*
Dental Restoration, Temporary*
Dental Stress Analysis
Materials Testing
Nanoparticles*
Pliability
Polymethyl Methacrylate*
Prostheses and Implants*
Silicon Dioxide
Stress, Mechanical
Surface Properties

Substances

Composite Resins
Silicon Dioxide
Polymethyl Methacrylate