Childhood caries remains a significant worldwide public health problem with untreated decay in primary teeth being the tenth most prevalent condition with untreated caries in permanent teeth being the commonest.1 Traditional restorative treatment approaches are expensive and are not available to all so cost-effective prevention or management approaches are needed. Silver diamine fluoride has been in active use in many countries and the first review of its effectiveness in 20092 suggested caries reductions ranging between 70–96%. The aim of this current review was to look at the latest evidence on the effectiveness of SDF in reducing caries in children.

An extensive database search had been conducted with no restrictions on publication date or language so the relevant studies should have been identified. The authors have chosen to include all prospective studies not restricting inclusion to randomised controlled trials so many of the included studies have no control group. Of those studies included in the meta-analysis only five of the eight had control groups. The authors have undertaken a risk of bias assessment using the Cochrane tool, although, it is not clear if this was conducted independently. It is not specifically stated how many of the included studies were randomised controlled trials and the random sequence generation was only considered to be low risk in four studies and none of the studies were considered to be low risk for allocation concealment. Given that SDF is known to cause black staining of the teeth it is interesting to see that five of the studies are rated as being at low risk of detection bias as this would be difficult to achieve.

These concerns would suggest that the quality of the available evidence in this review is likely to be low. However, the included studies have shown consistently high levels of caries arrest and some studies have demonstrated a better effect than fluoride varnish.3,4 SDF also offers a low cost alternative to other topical fluoride vehicles. Its main limitation remains the fact that it stains carious lesions black which may not be acceptable to many children and parents. A recent trial5 has examined a nano-silver diamine fluoride agent which was able to demonstrate effectiveness in arresting dentine caries but not stain teeth. For both this new SDF agent and the older 38% SDF solution high quality randomised controlled trials are needed to fully clarify their role in the prevention and management of childhood caries.