Introduction/objectives: white spot lesions (WSL) are enamel defects that can lead to esthetic concerns when located on facial surfaces of anterior teeth. In recent years, resin infiltration has been suggested as a treatment to mask WSL and arrest non-cavitated initial carious lesions. This narrative review aims to summarize the current literature on this technique.

Data source: an electronic search on Pubmed, Embase and Scopus databases was conducted for human randomized clinical trial (RCT), prospective and retrospective cohort studies, reviews, meta-analysis, case reports, and in vitro studies. The key words used in the search were: Resin infiltration, White spot lesion, White spot lesions and caries.

Results: the current literature suggests that resin infiltration might be an effective treatment to mask white spot lesions and arrest initial non-cavitated carious lesions. The concept of infiltrating carious lesions aims to occlude the porosity in the carious lesion thus inhibiting the diffusion of cariogenic acids. This procedure utilizes capillary forces to carry methacrylate resins (infiltrants) with high penetration coefficients into the porous enamel. The resin refractive index is closer to the refractive index of enamel, which gives this material the ability to mask white spot lesions.

Conclusion: color masking with resin infiltration seems successful and stable in the short-term. However, more clinical data is needed to report long-term masking effect.