Key Aspects of Working with 8th Generation Adhesive Systems in Direct Restorations: A Case Study of Clearfil Universal Bond Quick

To analyse structural changes in dental hard tissues associated with the use of the 8th generation adhesive system (Clearfil Universal Bond Quick (CUBQ) under various adhesive application protocols; to determine the most effective clinical strategy depending on the operative conditions; and to propose refinements to the application technique for the investigated adhesive aimed at enhancing the functional performance of subsequent restorations. A systematic review of current literature was conducted across electronic databases including PubMed, Google Scholar, and the Cochrane Library, in accordance with the PICO framework. The selected studies focused on the application of CUBQ under different clinical protocols for direct restorations. Based on the findings of this systematic review, a table was constructed, summarizing the studies and their outcomes according to the strategies of using CUBQ. The systematic review revealed that the etch-and-rinse technique demonstrates superior bond strength and durability between the adhesive and dental hard tissues. However, it requires strict adherence to the protocol, particularly when applied to dentin. The self-etch mode minimized nanoleakage and postoperative sensitivity but may be less effective on intact enamel. Factors such as dentin condition, timing of adhesive application, proper placement of the dental matrix, and others must be carefully considered when selecting the optimal strategy for working with CUBQ. Additionally, the use of chemical agents (NaOCl, HOCl, EDTA, sulfonates) to treat dentin improves the adhesive properties of CUBQ, particularly in the SE mode. The quality of direct restorations using CUBQ is directly influenced by the etching mode, the condition and type of dentin, the adhesive strategy, and the application of chemical agents. © 2025 Elsevier B.V., All rights reserved.