Dimensional stability of molds obtained with late storage alginate

Abstract

Introduction

Recently, some extended-pour alginate impression materials have been placed in the market. However, there is no consensus in the literature regarding the dimensional stability of these materials during these storage.

Objective

To evaluate, through the experimental model, the durability and velocity with respect to dimensional alteration, analyzing the material and detecting distortions.

Material and method

The material for molding in this test was alginate (Hydrogum 5, Zhermack). A cylindrical metallic matrix was used to make the moldings with: 38 mm of external diameter, 30 mm of internal diameter and superior of the upper series of the card 3d transport lines with each 25 mm in length and 20, 50 and 75μm in width. After the time of jellification / polymerization of the molding material, 16 molds were inserted in a doser and were photographed with a digital camera (Canon EOS Rebel 3Ti, Canon) associated with a software for analysis of sacred images (ImageJ 1.52a, US National Institutes of Health, DI). The calibration of the ruler was performed in 10 cm and then in 3 lines were means 3 (three) times to obtain a mean of the lengths of the lines. The photographs were taken at the following intervals: immediately, 24, 48, 72, 96 and 120 hours after being cast.

Result

The data were found when compared with the other parts of the reading time (p <0.001) and when compared to the execution after 24 hours of locomotion with the other parts of the time (p <0.001). The rest time of 48 hours, 72 hours, 96 hours and 120 hours were compared to each other.

Conclusion

The molds of the tested alginates can be stored for 5 days in 100% relative sauce.

Descriptors:
Dimensional measurement accuracy; dental impression material; alginates