Current status and rationale for composite inlays and onlays.

Abstract Composite inlay systems, now available to the dental profession, are classified and evaluated. Principle motives for their deployment are the aviodance or reduction of in situ polymerisation shrinkage and the optimisation of restoration contour and adaptation. The criteria for placement of direct or indirect composite inlay restorations are critically reviewed in relation to alternative materials and operative procedures. Dimensions of typical molar and premolar inlay cavities are presented and interim guidelines for inlay cavity design are discussed.