DOI: 10.36347/sjams.2017.v05i10.063

Pages: 4128-4139

Alginate impression materials are most commonly used materials to take preliminary impression during the prosthetic treatment. They have several advantages, like hydrophilic properties during the contact with saliva or gypsum, easy to dose and cheap compare to other type like silicone for example. With alginate, it is a common problem with the stability during the time especially after opening the original container. Each raw material used during the alginate production contain a small concentration of water, and after storage it catalase the reaction in solid phase. Purpose of this study was to test the alginate impression materials storage at room temperature during a time, to see the change in the mechanical properties.Seven kinds of commercial alginate were storage in plastic jars after opening the original containers during 3 months’ time. One composition of alginate was prepared in laboratory condition and tested in the same conditions like market products. Before preparing this composition sample of each raw material was tested at the water concentration. Following mechanical properties of alginate were tested during the ageing time: setting time, compressive strength, recovery for deformation, strain in compressive and compatibility with gypsum. Alginate impression materials after storage have lower mechanical properties compressive strength after 3 months is reduced about 10%, setting time is shorter, permanent deformation is increasing about 10 % from original value. All the commercial materials, Heraus Alligat Chroma (Heraeus Kultzer), Aroma Fine Plus (GC) Hydrogum 5, Hydrocolor 5 (Zhermack), Kromopan (Lascod), Ypeen Premium, Elastic Cromo ( Spofa) and sample X1 pass ISO 1563:1990. Alginate impression materials must be storage at original container, to protect from external humidity. After opening the package materials should be storage in plastic jars good closed. Raw material for alginate impression material production contains some water, which ca