Cost-effectiveness of silver diamine fluoride depends on caries activity: A decision analytic model.

Introduction: The study sought to assess the cost-effectiveness of silver diamine fluoride (SDF) relative to sodium fluoride varnish (NaF), and direct restorations placed chairside or under general anaesthesia (GA), accounting for caries activity.

Methods: An analytical decision tree model was developed with clinical data from multiple centres to evaluate the four treatment options among all children aged 1 to 6 years in Singapore (N=231,880) over a 12-month time horizon. Base-case scenarios consisted of children with low- (1 carious tooth) and high- (7 carious teeth) caries activity. Incremental cost-effectiveness ratios (ICER) and net monetary benefits (NMB) were tabulated with the outcomes set to be the control of active caries and avoidance of tooth extractions. Deterministic and probabilistic sensitivity analyses were conducted.

Results: Overall, SDF was less effective than direct restorations placed chairside but was less costly. For children with low-caries activity, the ICER for SDF was $9 per caries-controlled tooth, and $68 per extraction avoided. For children with high-caries activity, the ICERs were $267 and $1 909 respectively. At a willingness-to-pay threshold of $30, the NMB was negative (favours restorations) for caries control in children with low-caries activity and positive (favours SDF) for all other situations. In the low-caries activity group, SDF had a 41.5% probability of being cost-effective for caries control and 49.2% probability of being cost-effective for the avoidance of extraction. The corresponding probabilities for the high-caries activity group were 99.8% and 100%. The NMB of SDF increases proportionally with caries activity, suggesting utilisation of SDF should depend on caries activity. Results were most sensitive to changes in relative cost, and effectiveness of SDF/direct restorations.

Conclusion: SDF was cost-effective in most situations except for caries control in children with low-caries activity. Direct restorations were more effective and should be considered in low-caries activity children.