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