Potential discolouration of silver diamine fluoride versus silver diamine fluoride/potassium iodide in primary teeth: a randomised clinical study

Aim This study aimed to evaluate the potential discolouration and carious lesion arresting effect of silver diamine fluoride (SDF) and silver diamine fluoride/potassium iodide (SDF/KI) in the treatment of carious primary teeth. Materials and method A total of 30 carious primary canines were randomly assigned to treatment groups where Group I was treated with SDF while Group II was treated with SDF/KI. Caries arrest was assessed based on consistency and stability of lesion size while the discolouration of treated lesions was assessed digitally using a VITA Easyshade spectrophotometer. Results Both treatments demonstrated 100% efficacy in arresting active caries lesions. Regarding discolouration, the total colour difference represented by delta E (ΔE) was 16.45 ± 5.69 for Group I compared to 9.54 ± 3.09 for Group II immediately post-operative, with a statistically significant difference (p = 0.003). Both groups showed similar values at 1, 3, 6 and 12 months after the treatment, with no statistically significant difference. No incidence of serious adverse effects related to either treatment and the majority of parents/guardians were satisfied with both treatments compromising their child's aesthetic appearance. Conclusions Both SDF and SDF/KI are effective in arresting carious lesions in primary teeth but in terms of the discolouration potential, the use of KI significantly reduced the discolouration caused by SDF immediately post-operatively. Unfortunately, marked discolouration was recorded in the subsequent follow-up visits, compromising the aesthetic outcome.