This is a community-based, parallel-group, double-blinded randomised controlled trial aimed at evaluating the effectiveness of single and dual applications of 38% Silver Fluoride (SF) in arresting dentinal caries among Malaysian preschool children aged 4 to 6 years.

The main questions this study aims to answer are:

i) Does dual application of 38% Silver Fluoride differ from single application in arresting dentinal caries lesions after 6 months? ii) How does SF application influence oral health-related quality of life (OHRQoL) among preschool children, as measured by the Malay-ECOHIS questionnaire? iii) Is there a correlation between caries arrest and changes in Oral Health-Related Quality of Life (OHRQoL) measured using the Malay-ECOHIS questionnaire?

Researchers will compare children receiving a single application of 38% Silver Fluoride with those receiving dual applications to determine whether more frequent application improves caries arrest outcomes.

Participants will:

i) Undergo oral examination for assessment of dentinal caries using ICDAS criteria.

ii) Receive 38% Silver Fluoride application at baseline, with the dual-application group receiving an additional application at 3 months.

iii) Attend follow-up assessments at 3 and 6 months to evaluate caries arrest status.

iv) Have parents or guardians complete the Malay-ECOHIS questionnaire to assess changes in OHRQoL.

Inclusion Criteria:

1. Children aged 4-6 years enrolled in selected preschools.
2. Presence of at least one active dentinal caries lesion.
3. Parental or guardian consent obtained.
4. Asymptomatic cavitated dentine carious lesions in primary teeth.
5. Parents/caregivers who understand the Malay language.

Exclusion Criteria:

1. Clinical signs or symptoms of irreversible pulpitis or dental abscess/fistula.
2. Systemic illness or medical contraindications for SF use.
3. Developmental abnormalities of tooth structure, including amelogenesis imperfecta or dentinogenesis imperfecta.
4. History of allergy or sensitivity to dental materials, including silver or fluoride contained in silver fluoride (SF).
5. Children who have received professionally applied fluoride within the past six months at the time of recruitment.
6. Arrested caries lesion.
7. Children presenting with oral ulceration or mucositis.
8. Uncooperative behaviour precluding oral examination.
9. Children with pre-shedding tooth mobility

Individual participant data will not be publicly shared due to participant confidentiality and ethical considerations

This is a double-blinded study. Participants and outcome assessors will be blinded to group allocation. A placebo, normal saline in a foil-wrapped bottle, will be used at the 3-month visit in the single-application group to maintain blinding