June 2023

Objectives: Literature on the effectiveness of theory-based oral health education on the oral hygiene of children is limited. We aimed to determine the effectiveness of an health behaviour theory-based school oral health education intervention on 1) oral hygiene and 2) oral health-related knowledge, attitude and practices among 6–12-year-old children in Kerala, India. Methods: Cluster randomized controlled trial. Sixteen class divisions (clusters) were randomized into intervention and control groups of 225 and 228 children respectively. Primary and secondary outcomes were plaque score as measured using the simplified oral hygiene index (OHI-S) and oral health-related knowledge, attitude and practices respectively. The intervention group received structured oral health education classes for three months and materials including pamphlets. Children in the control group were not given the classes or materials. Results: Post-intervention OHI-S scores in the intervention group and control groups were 1.65 and 2.17 respectively (difference = -0.52, 95%CI -0.86, -0.18). All the secondary outcomes improved in the intervention group compared to the control group. Conclusions: The intervention improved the oral hygiene status, oral health-related knowledge, attitude and practices of the children. Longer term follow-up and economic appraisal are needed to help policymakers plan and develop OHEI based on health behaviour theories. Keywords: Children, India, Kerala, cluster randomized controlled trial, oral health education