Effect of various incremental techniques on the marginal adaptation of class II composite resin restorations

The effects of various placement techniques on the formation of microgaps were compared at the gingival margins of class II composite resin restorations. Three incremental techniques (occlusogingival layering, oblique layering, and faciolingual layering) and two one-bulk techniques of placing composite resin were studied. In the first one-bulk placement technique the composite resin was photocured occlusally; in the second one-bulk technique the composite resin was irradiated from three directions; facial, lingual, and occlusal. None of the incremental placement techniques improved the adaptation at the gingival margin compared with a one-bulk technique irradiated occlusally. However, the one-bulk placement technique that was irradiated from three directions created a substantial marginal discrepancy.