Structure of surface coatings on teeth. A review.

Classification by origin and structure of the many different coatings which occur on the surfaces of teeth and artificial surfaces exposed to the oral environment necessitate a revision of the terminology used to describe these coatings. Numerous gaps still exist in our understanding of the origin, morphological structure and chemical composition of many of these structures, notably the ones in the "acquired" category. The proposed classification of surface coatings, although not definitive, may provide a more accurate categorization of these structures in the light of contemporary knowledge.