Comparative evaluation of saturated and 10% potassium iodide in reducing silver diamine fluoride staining under RMGIC...

Silver diamine fluoride (SDF) effectively arrests caries lesions, but its major drawback is staining. Potassium iodide (KI) has been suggested to minimise this effect. The present clinical trial compared 10% KI and saturated KI in reducing SDF-induced staining under resin-modified glass ionomer cement (RMGIC) restorations in primary teeth.

A triple-blinded, parallel-design randomised clinical trial was conducted on 46 primary teeth meeting standardised ICDAS criteria to eliminate selection bias. Teeth were randomly assigned to Group A (10% KI) or Group B (saturated KI). Changes in staining were quantified using mean grey values at baseline and follow-up intervals. Secondary outcomes included parental satisfaction assessed through a structured questionnaire.

A significant difference in mean grey value change was observed between groups at the 15 day interval, with saturated KI showing greater stain reduction. However, no significant differences were found at subsequent follow-ups. Parental satisfaction related to aesthetic outcomes varied between the two groups.

This is one of the first clinical studies, beyond predominantly in vitro evidence, to evaluate KI formulations for SDF stain reduction under RMGIC restorations. Neither 10% KI nor saturated KI provided consistent long-term aesthetic benefits, although short-term improvements and positive parental acceptance were noted. Future trials with larger samples and adjunctive approaches are warranted to identify more reliable strategies for managing SDF-related discolouration.