Effect of Oral Hygiene Instruction by an Educational Film versus Practical Face-to-Face Instruction on Simplified Oral Hygiene Index of Third Graders: A Clinical Trial

<b>Objectives:</b> Oral hygiene instruction is an important step to promote oral health. Educational health promoting interventions focus on knowledge enhancement and adoption of optimal oral health behaviors. The visual media can greatly help in this respect. This study aimed to compare the effect of an educational film versus practical face-to-face instruction on Oral Hygiene Index-Simplified (OHI-S). <b>Materials and Methods:</b> This parallel-design single-blind clinical trial was conducted on 120 third-graders (9-year-olds) in Hamadan city in 2020 who were selected by convenience sampling from 4 random schools. They were randomly assigned to two groups of educational film and practical face-to-face instruction. An educational film was sent to all students through Shaad mobile application. The second group received practical face-to-face oral hygiene instructions. Next, all students were requested to use their own toothbrush for one month. The OHI-S was calculated for students at the onset of the study and at one month after the intervention. Data were analyzed by ANOVA using SPSS version 24. <b>Results:</b> In the practical instruction group, the OHI-S was 1.55±0.45 at one month after the intervention, showing a reduction by 0.25±0.11 units. In the educational film group, the OHI-S was 1.48±0.39 at one month after the intervention, showing a reduction by 0.29±0.19 units. The two groups had no significant difference regarding the reduction of OHI-S (P=0.10). <b>Conclusion:</b> Both practical instruction and educational film effectively decreased the OHI-S of students. Considering the ongoing COVID-19 pandemic, educational film can serve as a suitable alternative to practical face-to-face oral hygiene instruction.