Disclosed are methods for detecting demineralization of a surface of a tooth, comprising a) contacting the tooth of a subject with an orally acceptable, binding composition comprising a binding agent that binds to a demineralized surface of the tooth; b) removing unbound binding compound; c) contacting the tooth with an orally acceptable, detector composition comprising a probe compound that reacts with the binding agent to form a visually detectable reaction product; and d) detecting formation of the reaction product as an indication of the presence or extent of surface demineralization of the tooth. Systems, kits, and compositions for practicing the methods are also provided.