An In Vitro Study Comparing Marginal Leakage of Resin Composite Restorations on Selectively Excavated Caries Lesions and Silver Diammine Fluoride.

<b>Purpose:</b> To evaluate the effect of selective caries excavation and the application silver diammine fluoride (SDF) on marginal leakage of resin composite restorations. <b>Methods:</b> A total of 128 samples from deidentified carious and noncarious extracted teeth were randomly divided into 4 groups: Group 1-complete caries excavation with no SDF; Group 2-complete caries excavation with SDF application (Advantage Arrest ® silver diamine fluoride 38%, Elevate Oral Care, LLC; West Palm Beach, FL, USA); Group 3-selective caries excavation with no SDF application; Group 4-selective caries excavation with SDF application. Following a period of storage in distilled water, microleakage measurements were done using a stereo-optical microscope at 40X magnification at 2 points on each sample. The independent samples t-test and Mann-Whitney U test were used for assessing statistical significance. <b>Results:</b> A significant difference was found when comparing Groups 1 and 3 (P<0.001) and Groups 2 and 4 (P<0.001) for microleakage. No significant difference was observed when comparing Groups 1 and 2 (P=0.37 and P=0.69, respectively) or Groups 3 and 4 (P=0.39 and P=0.80, respectively) for microleakage assessments. A general positive trend in microleakage values was noted between the complete caries excavation Groups (1 and 2) and the partial caries excavation Groups (3 and 4). <b>Conclusions:</b> The results indicate a significant difference in microleakage between complete and partial caries excavation groups. There was no significant difference in microleakage values within the complete caries excavation Groups (1 and 2) and the selective caries excavation Groups (3 and 4), regardless of SDF application.