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Influence of Chemical Composition on the Properties of Experimental Silicone-Based Soft Lining Composites

Jabłońska-Stencel E., Pakieła W., Żmudzki J., Kasperski J., Chladek G.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 3

1371--1377

EN

The paper analyses the influence of chemical composition of silicone-based composites on their properties in the aspect of using them as long-term soft denture lining materials. Different concentrations of filler and methylhydrosiloxane-dimethylsiloxane copolymer were used. The filler was introduced into the composite with mechanical mixing combined with ultrasonic homogenization. Scanning electron microscopy was used to investigate the quality of filler dispersion. Shore A hardness, tensile strength, sorption, solubility and tensile bond strength to poly(methyl methacrylate) were measured. Tests show satisfactory results for some experimental composites, which met all the requirements for such materials.

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The properties of experimental silicones reinforced with silica fillers for dentistry

Kalamarz I., Chladek G., Pokój M., Łukowiec D., Krawczyk C., Stencel R., Jabłońska-Stencel E.

Archives of Materials Science and Engineering

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2016

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Vol. 81, nr 1

22--29

EN

Purpose: Silicone materials crosslinked during the hydrosilylation reaction are common in dental prosthetics and dentistry. These materials are characterized by a relatively very good properties. However, one of the fundamental problems associated with the use of such polymers is a low resistance to microbial colonization. Numerus fillers with antimicrobial potential have been used experimentally for a decade. Anyway point of concern in this type of work is the use of commercially available materials as the matrix. However, the composition of the matrix for this materials is not clearly known. Therefore, the aim of this study was to obtain a two-component silicone material, crosslinking at room temperature, with properties corresponding to the needs of dental prosthetics, in particular as denture soft linings. Such material would be a starting point to obtain more sophisticated compositions, however, of known composition in full. Design/methodology/approach: As the matrix the mixtures of polymers were prepared. As the “catalyst” component a vinyl polydimethylsiloxane with platinum catalyst in xylene was prepared. As the “base” component a mixture of vinyl polydimethylsiloxane with methylhydrosiloxane - dimethylsiloxane copolymer was made. One of the two fillers differing in the functionalizing was added into prepared substrates (10 or 15% by weight) and ultrasonically homogenized. The Shore A hardness, tensile strength, bond strength to denture base material, water sorption and solubility were investigated. Measurements were made after different aging periods in distilled water at 37±1°C. Findings: The study showed an increase in mechanical properties with increasing concentrations of fillers. The type of filler significantly affects the test results. Increasing the aging time effects on increasing the hardness of materials. Water absorption and solubility were within the desired range. Research limitations/implications: Research limitations/implications The results of the presented research may be generally dependent on technology of fillers introduction into polymers matrix. Practical implications: The results show promising properties of the tested materials. It can be used as starting material for further studies on soft or super soft denture lining and other materials characterized by similar requirements. Originality/value: The method of receiving silicone - based composites with properties required for the selected prosthetic materials, especially denture soft linings was presented. Their properties were similar to commercially available products.

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The method of evaluation of the abilities of the lining soft materials to relieve the mucous membran

Chladek G., Żmudzki J., Malara P.

Archives of Materials Science and Engineering

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2013

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Vol. 64, nr 2

125--134

EN

Purpose: The presentation of a simple method of evaluation of the effectiveness to relieve the mucous membrane under thednture through soft lining materials, which is based on the analysis of creep curves and energy dissipated by the samples during the cyclic compression. Design/methodology/approach: On the testing machine there were conducted studies of time characteristics and there was determined the energy dissipated by the samples during the cyclic compression. The results were subjected to the analysis of variation ANOVA (α=0.05) with the Newman-Keuls post-hoc test. Findings: The presented method allowed to conduct the evaluation of abilities to relieve the mucous membrane of soft lining materials significantly different in hardness. The studies showed that the softer materials characterised with a greater ability to dissipate energy, nevertheless, after taking the load off, the return to the original form in case of materials with the lowest hardness lasted much longer. The samples of softer materials with large values of stress underwent much greater stiffening, Research limitations/implications: Limitations not allow the full translation of the obtained results into the expected results of clinical trials. The demonstrated relations between the behaviour of the samples and the hardness of materials are proper for the tested materials, but not necessarily for other materials of a similar hardness. Practical implications: The presented methodology of the research is even closer to the expected clinical reality, when the alveolar ridge is more uniform and flat, but in order to obtain an even fuller image of the situation in case of uneven or sharp alveolar ridges, one should conduct additional tests with the method consisting of the load of the samples with a properly shaped penetrator. Originality/value: The advantages of the presented methods are: the possibility for a quantitative use of the comparison of energy dissipated by the samples and the estimation of the material reaction while maintaining the possibility to use the tests of variable values of stresses, what enables an easy association of the obtained results with the values of stresses, which cause pain sensations in the mucous.