A Shapiro–Wilk test was used to assess the data for normality. One-way ANOVA was performed to compare the contact angle, mucin absorption, and log CFU among the four experimental groups. A Bonferroni test was carried out for multiple comparisons of the result. All the analyses were conducted using IBM SPSS version 2.0 software (IBM Corporation, Armonk, New York, NY, USA). The cut-off level for significance was taken as 5% for all the analyses.