Microleakage at the tooth-restoration interface poses a significant challenge in restorative dentistry, contributing to secondary caries, pulpal inflammation, and restoration failure. This systematic review examines the effect of water flossing on microleakage in self-adhesive resin cement (SARC) and resin-modified glass ionomer cement (RMGIC). Evidence was synthesized from studies that evaluated microleakage from water flossers using dye penetration and other analytical techniques under simulated clinical conditions. The results show that water flossers significantly reduce microleakage in SARC restorations by increasing marginal integrity and bond strength, outperforming traditional brushing methods. In contrast, their effect on RMGIC was modest, potentially due to the material's distinct adhesive properties and composition. Water flossers were found to effectively clean interproximal and subgingival areas, contributing to improved restoration longevity and reduced plaque accumulation. However, the variability in experimental protocols highlights the need for standardized methodologies in future research. This review emphasizes the clinical value of water flossers as a supplementary oral hygiene tool, especially for patients with SARC restorations. Further long-term clinical studies are recommended to confirm these findings and optimize water flosser settings for different dental materials.
