Effects of Fragaria vesca leaf extract on the initial pellicle-an atypical representative among polyphenol-containing substances

Abstract

Objective: Polyphenol-containing mouth rinses are known to improve the protective properties of the dental pellicle against acids by increasing its thickness and density. Even though fragaria vesca (wild strawberry) leaf extract (WSLE) contains high concentrations of polyphenols and possesses beneficial properties on the oral biofilm, its effects on dental pellicle have not been studied yet. Methods: Transmission electron microscopy (TEM) and atomic adsorption spectrometry (AAS) were used to visualize the ultrastructure of the 6-min and 120-min pellicle as well as measure the calcium release of the enamel surface after rinsing for 1 min with WSLE or water as control and applying different acidic challenges (1% citric acid, 0.01 M HCl or water). Results: Mouth rinsing with WSLE did neither increase thickness or density of the pellicle nor improve its protectivity against acids. Compared to water- rinsing, samples showed equal or even higher dissolution of the pellicle upon acidic attack. AAS experiments demonstrated an increased calcium release and the leaf extract was shown to possess an appreciable calcium content. Conclusion: WSLE represents an outlier in the group of polyphenol-containing mouth rinses in terms of its effects on the dental pellicle. The increased calcium release upon rinsing and its appreciable calcium content suggests it may act as a calcium source for the dental pellicle. Clinical significance: Based on its previously demonstrated anti-adhesive properties on the oral biofilm and the current results on its remarkable calcium content, WSLE presents as a promising candidate for daily mouth rinse use, warranting further clinical studies.