Stratification of composite restorations: systematic and durable replication of natural aesthetics.

A thorough knowledge of the internal structure of natural dentition provides invaluable information for increasing the aesthetic potential in dental restorations. To achieve the optimal aesthetic results, this knowledge must be integrated in a systematic therapeutic procedure. The learning objective of this article is to guide the practitioner in clinical case analysis, evaluation, and the application of a personalized technique of stratification for each individual case in direct composite restorations. The article evaluates treatment demarcations, differences in composite stratification between anterior and posterior teeth, color selection, and the "sandwich technique." The treatment protocol section discusses the element of reference, which can be either an adjacent natural tooth or provisional restorations, permitting the diagnostic study of a more extensive case. The structure of the element of reference is analyzed as to the enamel, dentin, and incisal edge, and replicated. Since light penetration is different in the anterior and posterior dentition, the color stratification must differ accordingly. The "worn" tooth must be distinguished from the "unworn" tooth. In color selection, the luminosity and saturation of the teeth are evaluated first; tint is selected from the element of reference.