Scanning electron microscopy of some acrylic resin specimens after the addition of different types of fibres

Abstract EN

Objective: The aim of this scanning electron microscopic study was to investigate the interface characteristics between acrylic resin and five different types of fibres, which are thought to play an important role in the reinforcement of the denture base.

The fibres used are poly methyl methacrylate, polyethylene, glass, carbon and silk.

Methods: Initially 140 poly (methyl methacrylate) denture base resin specimens reinforced with different fibres in a longitudinal and woven orientation was prepared for testing both transverse bend and impact strength testing.

The specimens were divided according to the fibre type into seven groups of which two were control groups.

A selection of 21 acrylic resin specimens which had undergone transverse bend and impact test procedures were prepared for examination using the scanning electron microscope.

After the specimens had been broken by the test machine, each of the fractured surfaces were subjected to acid etching, which reveals details of the margins of the fibres and differentiates them from the matrix.

The specimens were prepared for examination under the scanning electron microscope (Model S600, Cambridge Scientific Instruments Ltd, Cambridge, UK).

Results: The fractured surfaces of the acid etched acrylic resin specimen containing silk, polyethylene, glass strand and carbon fibres showed that the fibres can be seen protruding through the fracture surfaces indicating poor bonding with the matrix.

The fractured surfaces of the acid etched acrylic resin specimen containing poly methyl methacrylate fibres and woven glass fibres showed that the fibres are visible on the fracture surfaces and are well integrated within the resin.

Conclusion: Examination of selected specimens under the scanning electron microscope demonstrated that the specimen containing poly methyl methacrylate fibres and woven glass fibres showed that the fibres are well integrated in the matrix of the acrylic resin with no evidence of an interface between the matrix and the fibres.