Randomized controlled clinical trial of resin infiltration in primary molars: 2 years follow-up

Objective: The aim of this split-mouth, randomized, controlled clinical trial was to evaluate the efficacy of resin infiltration in controlling the progression of non-cavitated proximal lesions in primary molars after two-years follow-up. Methods: Fifty healthy children presenting at least two primary molars with proximal lesion detected radiographically (in the inner half of enamel or the outer third of dentin) were included in the study. The proximal lesions were randomly allocated into resin infltration+flossing (test group) or flossing (control group). All patients received oral hygiene instructions for daily brushing with fluoride toothpaste (1100 ppmF) and flossing. The proportion of caries progression was compared using the McNemar test. The main outcome after 2-years, caries progression in the radiography was assessed by pair-wise reading by an independent examiner who was blind regarding the treatment. Results: The sample comprised 28 (56%) girls and 22 (44%) boys with a defs of 7,3 (SD = 6,5), mainly of moderate (46%) to high (48%) caries risk. Results after one year were published previously. After 2-years, 29 (58%) patients were assessed. Caries progression was observed in 24.1% (7/29) of the test lesions, compared with 55.2% (16/29) of the control lesions (p = 0.012). The therapeutic effect was 31.1% and the relative risk reduction (RRR) was 56.3%. Eigth lesions from the control group and two lesions from the test group progressed to the inner third of dentin and were restored. Conclusions: In conclusion, resin infiltration was more efficacious in controlling proximal caries lesions in primary molars than non-invasive approach alone. Clinical Significance: The results indicate that resin infiltration was an efficacious method in controlling proximal caries lesions in primary molars after 2 years, even in patients with high caries risk, reaffirming the results of 1-year follow-up.