2.6. Data Analysis

Statistical software, JMP 9.0 (SAS, Cary, NC, USA), was used for all data analyses. One-way analysis of variance (ANOVA) and comparison of the means using Tukey’s honestly significant difference (HSD) or Wilcoxon/Kruskal–Wallis rank sum test were performed on the mean oxidative stress responses as measured by salivary lipid oxidation in the control and test samples. The SLO was also reported as delta SLO as the arithmetic difference between the measured salivary TBARS in the control and the iron-containing test samples. To normalize the measured iron-induced SLO levels, the delta SLO values in micromoles of TBARS were divided by the concentration of total iron in milligrams. All statistical analyses were performed at alpha level of 0.05, and results are presented as means ± standard error (SEM).