A Randomized Clinical Trial of Silver Diamine Fluoride to Arrest Early Childhood Caries in Young Children

Good oral health during early childhood sets the foundation for a lifetime of optimal dental health. Unfortunately, many Canadian children develop Early Childhood Caries (ECC), defined as caries in the primary dentition in those < 72 months of age. ECC is a significant concern as not only can it increase the risk for caries throughout childhood and adolescence, but severe forms can impact health and well-being. Many with ECC suffer from an aggressive subtype, called severe ECC (S-ECC), which frequently requires rehabilitative dental surgery under general anesthesia (GA).

There is an urgent need to implement public health strategies to reduce the proportion of children developing ECC, especially S-ECC, and to manage effectively children who already have the disease. The challenge is that there are few effective interventions. Traditional primary prevention modalities have had little impact on reducing the incidence and severity of ECC in North America. Until recently there have been no effective non-surgical products for secondary prevention available. Though primary prevention is always preferred, secondary prevention can reduce the morbidity from caries and preserve the function of affected teeth until exfoliation.

Recent reports highlight the anti-caries effects of silver diamine fluoride (SDF). One systematic review and meta-analysis reported that 38% SDF is safe and effective in arresting dentin caries in primary teeth resulting in the arrest of 81% of active caries lesions. The recent American Dental Association (ADA) report on non-restorative management of caries prioritizes the use of SDF over other products to manage cavitated caries lesions. Despite this evidence, true consensus on the frequency of SDF applications in children with ECC is lacking. Further, the current American Academy of Pediatric Dentistry (AAPD) Clinical Practice Guidelines on SDF emphasize that research is needed on the use of SDF to arrest caries lesions in both primary and permanent teeth, specifically urging researchers to undertake randomized clinical trials (RCTs). SDF has the potential to arrest ECC in young children and delay treatment until children can be seen in outpatient settings, thereby reducing the need for rehabilitative dental surgery under GA.

While Advantage Arrest TM (38% SDF) received approval for clinical use in Canada in 2017, there has been little guidance on the frequency and duration of applications. Some proposed SDF protocols may not easily translate into dental public health clinical settings or work well in remote Indigenous communities, where access to care is often limited. Recommendations for frequent reapplication are not practical or realistic in these programs or remote regions where follow-up visits may be several months away and not within a matter of weeks. Since there was no clear protocol for dental professionals to follow for arresting caries in young children when SDF was approved for use in Canada in 2017, The investigators undertook a mixed-methods pilot feasibility study of SDF. Data from 40 children 40.2 ± 14.9 months of age are encouraging. Children with 239 active caries lesions in primary teeth underwent treatment with 38% SDF (followed by 5% sodium fluoride varnish/5%NaFV) at baseline and 4 months later. Treated lesions were assessed 4 and 8 months after baseline to determine arrest. The early childhood oral health impact scale (ECOHIS) questionnaire was completed at second and third visits to assess oral health related quality of life (OHRQoL). ECOHIS is a validated tool for use with parents/caregivers of children < 72 months of age. Arrest rates after one and two applications of SDF were 74.1% and 96.2%, respectively. OHRQoL was not found to be adversely affected by the success of SDF treatment. From these pilot data the investigators concluded that SDF is a promising agent to manage ECC, but at least two applications are recommended.

The purpose of this current study is to investigate the effectiveness of using SDF to arrest ECC in very young children randomized to different application frequency regimens. The investigators will also study potential oral microbiome changes in children receiving SDF treatment. The investigators hypothesize that two applications of SDF at different frequencies will yield similar arrest rates, and that SDF will negatively influence the population of cariogenic bacteria in the oral microbiome.