Figure 3.

The shrinkage vectors point in the direction of mass movement upon polymerization of resin composites. Bulk application of a bulk-fill composite resulted in an upward movement at the gingival margin of the proximal box (A). The application of a thin flowable liner (B) below the bulk application of a hybrid bulk-fill composite resulted in smaller shrinkage vectors in the proximal box and yielded a more favorable shrinkage movement toward the tooth–restoration interface (C); image reprinted with permission from Kaisarly et al., published by Elsevier 2022 [93].