J Adv Prosthodont.  2016 Oct;8(5):372-379. 10.4047/jap.2016.8.5.372.

Empirical study of alginate impression materials by customized proportioning system

• Kurtulus K
• Tüfekci K

• KMID: 2355441
• DOI: http://doi.org/10.4047/jap.2016.8.5.372

Abstract

PURPOSE
Alginate mixers available in the market do not have the automatic proportioning unit. In this study, an automatic proportioning unit for the alginate mixer and controller software were designed and produced for a new automatic proportioning unit. With this device, it was ensured that proportioning operation could arrange weight-based alginate impression materials.
MATERIALS AND METHODS
The variation of coefficient in the tested groups was compared with the manual proportioning. Compression tension and tear tests were conducted to determine the mechanical properties of alginate impression materials. The experimental data were statistically analyzed using one way ANOVA and Tukey test at the 0.05 level of significance.
RESULTS
No statistically significant differences in modulus of elastisity (P>0.3), tensional/compresional strength (P>0.3), resilience (P>0.2), strain in failure (P>0.4), and tear energy (P>0.7) of alginate impression materials were seen. However, a decrease in the standard deviation of tested groups was observed when the customized machine was used. To verify the efficiency of the system, powder and powder/water mixing were weighed and significant decrease was observed.
CONCLUSION
It was possible to obtain more mechanically stable alginate impression materials by using the custom-made proportioning unit.

Keyword

Alginate impression material; Alginate mixer; Mechanical properties of alginate; Preparing methods of alginate

MeSH Terms

Tears

Figure

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  Fig. 1 (A) Working principle of the machine and, (B) Cross-section view of the dust hopper.

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  Fig. 2 A photograph of the fully assembled device (A) and its schematic illustration (B).

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  Fig. 3 (A) Compression test setup, (B) Tensile test setup, (C) Split mould for tensile test specimen.

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  Fig. 4 A schematic diagram of the LVDTs installation for compression test.12

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  Fig. 5 Stress-strain curves of the selected VP-AM sample.

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  Fig. 6 Mechanical properties of VP-MM, VP-AM, and WP-AM under compression. (A) Modulus of elastisity, (B) Failure Strain, (C) Compressive Strength, (D) Resilience.

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  Fig. 7 Mechanical properties of VP-MM, VP-AM, and WP-AM under tension.(A) Modulus of elastisity, (B) Failure Strain, (C) Compressive Strength, (D) Resilience.

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  Fig. 8 Tear energy values of VP-MM, VP-AM, and WP-AM.

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