The effect of using a pre-brushing mouthwash (Plax®) on removal of tooth stain in vivo and in vitro

Abstract The aim of this study was to determine whether the use of a pre-brushing mouthwash Plax - reduced extrinsic tooth staining in vivo and in vitro. Firstly, in a double-blind placebo controlled cross-over study, 20 subjects with tooth staining used Plax® or a placebo for 14-day periods separated by a 1-month wash-out period. The area of stain was assessed before and after each mouthwash had been used from clinical photographs. Secondly, extracted 3rd molar teeth were stained with tea and chlorhexidine. After exposure to either Plax® or placebo, the teeth were brushed in a standardized manner. The area and intensity of stain were assessed before and after rinsing and brushing. Results of the study in vivo showed that the mean % stained area for any of the surfaces studied changed very little throughout the study. No statistically significant changes were detected (Student t-test, p > 0.05). Results of the study in vitro showed that the mean area of stain fell by 19% after exposure to Plax® and by 17% after exposure to placebo. No statistically significant changes were detected (Student t-test, p > 0.05). There were also no significant changes in intensity (Wilcoxon signed rank sum test p > 0.1).