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Published on: May 17, 2018
[Influence of positive pressure on gypsum bonded investments]
G M Vecchio1, R R Vaz, A E Rocha
1Faculdade de Odontologia da UFMG.
Abstract:
The work aims to investigate the influence of positive pressure to initial and final setting time, as well as the volume variation in course of the pressure carried out gypsum-bonded investment found at Dental Commerce. Seventy-six test samples were obtained, being five of them through conventional investing technique and seventy-one through technique by pressure. Gillmore needles were employed for determining the setting time, meanwhile for volumetric variation a mathematic formula had been applied. According to results, it was concluded that the use of positive pressure affected the initial and the final setting time and the volume after set.
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