Influence of water/powder ratio in the mineral and synthetic casts

  • Rudys Rodolfo De Jesus Tavarez
  • Rufino José Klug
  • Mayana Soares Vieira
  • Gisele Lima Bezerra
  • Matheus Coelho Bandeca
  • Leily Macedo Firoozmand

Abstract

Aim: To evaluate the influence of varying the water/powder ratio on the compressive strength of type IV mineral and synthetic casts. Methods: Four commercial brands of type IV mineral and synthetic casts were evaluated: Durone, Herostone, Fuji Rock, and Elite Rock. Ninety-six test samples were prepared from a silicone matrix, according to ADA’s standard no. 25. The samples were prepared according to the manufacturer’s recommendations with a normal water/powder ratio (n = 12) and with 20% extra water (n = 12), forming the control (A) and experimental (B) subgroups, respectively. Compressive strength tests were performed using a universal testing machine EMIC (DL 2000) with a load cell of 2,000 kgf/cm2. The obtained data were analyzed statistically using two-way ANOVA and Tukey’s test (α=5%). Results: The synthetic Elite Rock cast was statistically different from the one obtained when the portion of water indicated by the manufacturer was used; no significant differences were found in the remaining casts when the proportion of water was increased by 20%. Conclusions: the groups of synthetic and mineral casts differed and the water increase (20%) did not cause significant difference on the compressive strength of the materials.

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Published
2016-12-12
How to Cite
TAVAREZ, Rudys Rodolfo De Jesus et al. Influence of water/powder ratio in the mineral and synthetic casts. Brazilian Journal of Oral Sciences, [S.l.], p. 225-228, dec. 2016. ISSN 1677-3225. Available at: <https://www.fop.unicamp.br/bjos/index.php/bjos/article/view/415>. Date accessed: 16 july 2019.
Section
Original Research