Abstract
Background Alginate is a widely used irreversible hydrocolloid impression material in dentistry because of its ease of use, affordability, and acceptable clinical performance. Modification of alginate with additives may alter its physical and mechanical properties. This study evaluated the effect of incorporating vanillin at different concentrations into two alginate impression materials, Zelgan and Neocolloid. Methods Vanillin was incorporated into Zelgan and Neocolloid alginate impression materials at concentrations of 0.5% and 1%. The materials were mixed with deionized water using a figure-of-8 motion for 45 seconds and moulded in polyvinyl chloride moulds to prepare specimens. Gel strength, permanent deformation, gelation time, flow, and tear strength were evaluated using standardized methods. Data were analyzed using the Shapiro–Wilk test for normality, followed by ANOVA or Kruskal–Wallis tests with appropriate post-hoc analyses. Between-group comparisons were performed using the independent-samples t-test or Mann–Whitney U test. Statistical significance was set at P