Bioadhesion and bio-adsorption of proteins, glycoproteins and other biomolecules are ubiquitous phenomena in the oral cavity. While the protective role of the adsorbed salivary biomolecules on teeth (the acquired enamel pellicle) is well established, it has yet to be defined whether comparable processes occur on the desquamating oral soft tissues. The general term for these layers is pellicle, but due to the different characteristics of the coated surfaces the enamel pellicle and mucosal pellicle are their own entities. There is considerable information on the enamel pellicle, whereas only limited data are available on the mucosal pellicle. This can be attributed to the difficult standardized preparation of this biological structure. Based on the present knowledge the abundant and characteristic components of the mucosal pellicle include secreted soluble mucins (MUC5B, MUC7), membrane-associated epithelial mucins (MUC1), and to a lesser degree CA VI, sIgA, and cystatin. However, it seems to be of completely different ultrastructure as compared with the enamel pellicle. Since it is comprised of larger glycoproteins retaining water, it might be considered as a hydrogel, and it appears to have a lower tenacity than the enamel pellicle. Maturation and turnover are influenced by the delivery of salivary proteins, by the flow of saliva and the underlying desquamating oral epithelium. Its probable functions include lubrication and moisture retention. In general, the mucosal pellicle can be regarded as an underestimated key player in oral physiology.

Polyphenols are natural substances that have been shown to provide various health benefits. Antioxidant, anti-inflammatory, and anti-carcinogenic effects have been described. At the same time, they inhibit the actions of bacteria, viruses, and fungi. Thus, studies have also examined their effects within the oral cavity. This review provides an overview on the different polyphenols, and their structure and interactions with the tooth surface and the pellicle. In particular, the effects of various tea polyphenols on bioadhesion and erosion have been reviewed. The current research confirms that polyphenols can reduce the growth of cariogenic bacteria. Furthermore, they can decrease the adherence of bacteria to the tooth surface and improve the erosion-protective properties of the acquired enamel pellicle. Tea polyphenols, especially, have the potential to contribute to an oral health-related diet. However, in vitro studies have mainly been conducted. In situ studies and clinical studies need to be extended and supplemented in order to significantly contribute to additive prevention measures in caries prophylaxis.

Background: Bioadhesion and surface interactions on enamel are of essential relevance for initiation, progression and prevention of caries and erosions. Salivary proteins on and within initial carious and erosive lesions can facilitate or aggravate de- and remineralization. This applies for the pellicle layer, the subsurface pellicle and for proteins within initial carious lesions. Little is known about these proteinaceous structures related to initial caries and erosion. Accordingly, there is a considerable demand for an understanding of the underlying processes occurring at the interface between the tooth surface and the oral cavity in order to develop novel agents that limit and modulate caries and erosion. Objectives and findings: The present paper depicts the current knowledge of the processes occurring at the interface of the tooth surface and the oral fluids. Proteinaceous layers on dental hard tissues can prevent or aggravate demineralization processes, whereas proteins within initial erosive or carious lesions might hinder remineralization considerably and restrict the entry of ions into lesions. Conclusions: Despite the fact that organic–inorganic surface interactions are of essential relevance for de- and remineralization processes at the tooth surface, there is limited knowledge on these clinically relevant phenomena. Accordingly, intensive research is necessary to develop new approaches in preventive dentistry.