ADA و پيشرو ايراني با استاندارد شماره سه KERR, KEMDENT, HARRARD:i بررسي ميزان سيلان استنس هاي نوع

Evaluation of the flow of Harvard, Kemdent, Kerr and Pishro compounds based on no.3 ADA standard

Background and Aim: Compound is one of the oldest impression materials that is nowadays widely used. The flow of compound is one of the most important physical properties for impression. The aim of this study was to evaluate the flow of an Iranian made compound (Pishro) according to ADA standards and to compare with Kerr, Kemdent and Harvard compounds. Materials and Methods: According to ADA, two samples of each compound with the diameter of 10mm and the height of 6mm were prepared. The specimens were put in 37°C and 45°C at 2kg pressure in hot water bath. Changes were measured by a micrometer. Based on the percentage of changes to the original length, the compound flow in a special temperature was taken and compared with standard criteria. The data were analyzed using one-way and two-way ANOVA. Results: The flow Kerr compound in 37°C was according to BS 3880 standard but didnʹt meet ADA standard. The three others were in the standard range (P<0.05). In 45°C, the flow of the Kerr compound was according to ADA standard and the three others had less flow than standard requirements. It should be noted that Pishro compound was the weakest.(P<0.05) Conclusion: In 37°C the silane percentage of Kerr stance does not correspond with ADA standards, however; in 45°C the silane percentages of Kerr, Kemdent, Harvard approximate to that of standard sequentially but Pishro stance is the weakest one and its percentage is far from that of standard.