Currently, composite resins have become the material of choice for the restoration of posterior teeth. Although bulk-fill resins represent a tempting alternative due to their lower complexity and faster use, some dentists are reluctant to use this material. The objective is to compare the performance of bulk-fill resins and conventional resins in direct restorations of posterior teeth based on the literature. The databases that were used to carry out the research were PubMed/MEDLINE, Embase, the Cochrane Library and the WOS. This umbrella literature review complies with PRISMA standards and assesses the quality of studies using the AMSTAR 2 tool. With the application of the criteria of the AMSTAR 2 tool, the reviews were considered low to moderate. The overall meta-analysis, although without statistical significance, favours mostly the use of conventional resin, as it is about five times more likely to obtain a favourable result than bulk-fill resin. Bulk-fill resins result in a simplification of the clinical process of posterior direct restorations, which is an advantage. The performance in terms of several properties of bulk-fill resins and conventional resins showed that they present similar behaviour.
Keywords: abrasion; bulk-fill; composite resin; microleakage; modulus of elasticity; polymerisation shrinkage.