Atabek D, et al. - This split-mouth randomized controlled study aimed to compare the 2-year clinical performance of two restorative techniques and materials for posterior permanent carious teeth. In terms of clinical success, the sonic-resin placement system indicated similar results to incrementally placed conventional composite resin. Considering the advantages of providing up to 5 mm in a single layer, and the adjustability of the viscosity, bulk-fill composite restorations appeared to be a good alternative to posterior Class 1 composite restorations.