Seven-year-efficacy of proximal caries infiltration - Randomized clinical trial

We report efficacy of resin infiltration to arrest progression of caries lesions as compared with non-invasive measures and oral hygiene education alone after a mean observation time of seven years.

This randomized split-mouth placebo-controlled clinical trial included 22 young adults having 29 pairs of interproximal non-cavitated caries lesions with radiographic extensions into inner half of enamel (E2) or outer third of dentin (D1). Lesion pairs were randomly allocated to two treatment groups: infiltration (Icon, pre-product; DMG) or mock (control) treatment. All subjects received risk-related instructions for diet, flossing and fluoridation. The primary outcome was radiographic (digital subtraction radiography) lesion progression after seven years. Secondly, Kaplan-Meier-analyses were applied to analyze time-to-failure additionally including patients followed up for less than 54 months as well.

Two lesion pairs were excluded due to invasive treatment decision by another dentist, five lesion pairs were lost to follow-up prior to 54 months but included in the survival analysis. No unwanted effects could be observed. For the primary outcome in 17 patients followed up in mean for 84 months 2/22 infiltrated lesions (9 %) compared with 10/22 control lesions (45 %) progressed (p = 0.018). The relative risk reduction for test in relation to control was 80 % (CI 95 % = 19-95 %). For the survival analysis within a mean (SD) observation time of 73 (25) months mean failure rates of 1.3 % and 7.8 % could be observed for test and controls, respectively. Hazard risk (95 % CI) for caries progression was 6.6 (2-22) for the control compared with the test lesions (p = 0.002).

We conclude that resin infiltration of proximal caries lesions extending radiographically around the enamel dentin junction is efficacious to reduce lesion progression after a mean observation time of seven years.

This randomized clinical trial proves that caries infiltration is highly efficacious compared with non-invasive measures and oral hygiene education alone after a considerably longer observation time of 7 years than studied so far before.