Keilbassa AM, Müller J et al. Quintessence Int 2009; 40: 663–681

In this literature review, the authors cite a recent SEM study that showed resin tags only penetrate to a depth of 4.2- 5.5 μm. In another study using subtraction radiography, 43.5% of sealed early proximal lesions had progressed compared with 84.1% of untreated controls (flossing). Other studies were also unconvincing. '7 to 8% of the sealed lesions showed progression, compared to 12% rate in the control group (fluoride varnish)'.Examination of white spot lesions associated with orthodontic treatment has also been used to explore the 'resin infiltration concept'. 'Unsealed teeth had 3.8 times greater number of white spot lesions than did the teeth with sealants'. Although this paper lacks rigorous interrogation of the literature, and the results of the papers the authors have cited are equivocal, the possible efficacy of this technique should not be dismissed.