Study protocol of a cluster randomized controlled trial on oral health promotion programs for adolescents in Iran | Scientific Reports

Scientific Reports volume 15, Article number: 21380 (2025) Cite this article

To design and evaluate oral health promotion programs for high school students in underprivileged areas of Tehran Province. A multilevel intervention based on the PRECEDE-PROCEED model will target students aged 13–15 years across 18 schools in Southern Tehran, Iran. This randomized controlled trial is being conducted using multistage random sampling, 435 students in grades 7–9 will be divided into three groups: Comprehensive Intervention (CI), Less Comprehensive Intervention (LCI), and a control group. The CI group will receive interventions including group motivational interviewing for students and teachers, parental education, free oral hygiene kits, peer-supervised tooth brushing, and access to educational videos through the school learning management system. The LCI group will receive similar interventions, excluding supervised tooth brushing. The control group will follow routine oral care practices. Primary outcomes will include oral health knowledge, attitudes, and practices; secondary outcomes will comprise plaque and CAST (caries assessment spectrum and treatment) indices. Data collection will occur at baseline, and at 3- and 12-months post-intervention. Statistical analysis will assess the effectiveness of the interventions. This study aims to provide evidence for embedding oral health promotion in school curricula. Results could inform national public health strategies to improve adolescent oral health.

Adolescence is a critical period for adopting health-promoting behaviors. Oral health behaviors are key components of public health and are often established during this period1. Health-related behaviors established during adolescence significantly impact current and future well-being, influencing both quality of life and the health of future generations2,3,4.

Schools provide a convenient and cost-effective setting for promoting health among adolescents5. According to the World Health Organization, school-based oral health promotion programs (OHPPs) are effective means of improving the oral health6. Health promotion involves a combination of educational, organizational, and political strategies designed to change both behaviours and environments, leading to better health outcomes7.

Educational strategies involving sustained interventions, parental and teacher engagement, and behavior change theories are effective in raising awareness, promoting healthy behaviors, and reducing plaque and decay8. School-based OHP initiatives such as oral health education, supervised tooth brushing, and fissure sealants are recommended. Programs combining education for children, parents, and teachers with supervised brushing and fluoride toothpaste distribution have shown success9. Policy efforts should integrate oral health into school health programs and promote nationwide implementation, ensuring inclusivity across all socioeconomic groups10,11.

Iran, with a population of over 80 million, has approximately 13 million schoolchildren and nearly 7 million adolescents12,13. Dental caries and periodontal disease are common among Iranian adolescents14. According to the national oral health survey conducted in Iran in 2016–2017, the mean DMFT (Decayed, Missing, and Filled Teeth) score among 12-year-old Iranian students was reported as 2.09.Of this total, approximately 79.6% represented decayed teeth15. Globally, 60–90% of school-age children experience dental caries16. Prevalence of cigarette and hookah use among Iranian adolescents is 56.8% and 31.1%, respectively, which is alarming17. Adolescents in lower socioeconomic conditions are disproportionately affected by oral health risk factors18. Studies on refugees and migrants report high rates of tooth decay, periodontal diseases, and poor oral hygiene19.

Using fluoride toothpaste effectively prevents cavities20. Studies link insufficient brushing to higher caries risk21,22. Peer-led strategies, such as peer-supervised toothbrushing, are grounded in Social Cognitive Theory, which highlights the role of modeling and social reinforcement in behavior change. During adolescence, peer influence is especially strong, making peers effective agents for promoting oral health behaviors23. Studies have shown that peer-led interventions can improve oral hygiene practices, increase motivation, and are cost-effective in school settings24,25.

In Iran, oral health programs primarily focus on children aged 6 to 12, while few studies have addressed the growing need for health promotion programs targeting adolescents14,26,27.This study aims to develop and evaluate a practical, behavior-changing program to improve oral health among adolescents in deprived areas of the country, ultimately informing national health policy.

This study is a multicenter, parallel, randomized controlled trial comparing three groups: a comprehensive intervention (CI) group, a less comprehensive intervention (LCI) group, and a control group. Data will be collected at three check-ups: baseline, 3-month follow-up (short-term), and 12-month follow-up (long-term). The research protocol was approved by the Research Ethics Committees of Tehran University of Medical Sciences, School of Dentistry, code IR.TUMS.DENTISTRY.REC.1402.109. The study was registered in the Iranian Registry of Clinical Trials (https://irct.behdasht.gov.ir/; registration number IRCT20160910029765N4; registered on 24/11/2024). All methods were performed in accordance with relevant guidelines and regulations.

The primary outcomes are oral health knowledge, attitudes, and practices. Oral health knowledge, attitudes, and practices will be assessed using a validated questionnaire focusing on oral health behaviors and tobacco use28,29.

The secondary outcomes include CAST (caries assessment spectrum and treatment) and plaque indices. Detailed descriptions of the scoring systems are presented in Table 130,31.

Students aged 13 (grade 7) and 14 (grade 8) will be recruited from eighteen schools. These schools are located in Islamshahr and Ray. The inclusion criteria are students aged 13 and 14 years who have no systemic diseases or orthodontic brackets. Because of the 12-month follow-up period, the students’ grade at the end is 9, and their age is 15. Exclusion criteria include failure to obtain consent from either the student or their parent, as well as student transfer from the school during the study period.

To account for cluster randomization, the sample size was adjusted using a design effect of 1.4, and with a 20% anticipated attrition rate, the final sample included 145 participants per group. (total = 435 students across three groups)32.

This study will employ a multi-stage cluster-randomized design. The unit of randomization is the school-grade level. In this region, a total of 30 schools train our target age group. The randomization process comprises two stages. First, out of these 30 schools, 18 schools (9 girls’ schools and 9 boys’ schools) will be selected for the study (refer to the sampling method). To prevent contamination between the intervention groups and the control, 3 girls’ schools and 3 boys’ schools will be randomly assigned to the control group. In the second stage, the remaining 12 schools, each with seventh and eighth grades (a total of 24 school-grades), will be allocated to two intervention groups. A random number generator will be used to produce numbers between 1 and 24, with 12 non-repeating numbers assigned to the first intervention group and the remaining 12 to the second intervention group. This process will ensure an even distribution of schools across intervention groups, allowing for a reliable comparison of outcomes.

Since all the units participating in the study are included in the study at the same time, and blinding is not possible in this study (even for data analysis, because the operator will perform the analysis herself), sequence concealment random allocation is irrelevant.

This study was structured based on all nine phases of the PRECEDE-PROCEED model. Phases 1–3 were used for formative assessments to identify behavioral, environmental, and educational determinants. Phases 4–5 informed the design of tailored intervention strategies, and Phases 6–9 guided implementation and evaluation. This ensured a comprehensive and theory-based approach throughout the study. (Fig. 1)

Comprehensive intervention (CI) group: The interventions in this group compromises the followings: Teaching students and teachers will be conducted through a single group motivational interview (MI) session about oral health (hygiene and tobacco use), following the strategies outlined in “ motivational interviewing in groups”33. The session will be conducted by the researcher, who is trained in MI techniques as described in the referenced methodology. The MI session will last 45 min and will focus on enhancing motivation for healthier oral health behaviors and addressing ambivalence regarding hygiene practices, dietary habits and tobacco use and providing free toothbrushes and toothpaste; Educating parents will be conducted through a national platform named SHAD, an educational social media network used for communication between schools and families in Iran. Through this platform, parents will receive targeted educational content on oral health (hygiene and tobacco use), such as videos, articles, and infographics. To encourage parent engagement, interactive elements will be incorporated, such as online polls, question prompts, and discussion threads, where parents can share their thoughts, ask questions, and provide feedback. Regular reminders and notifications will also be sent to ensure active participation and engagement in the educational content. Examining the oral health of students by the peer group (health agents, who will be chosen through a vote by students among volunteers, and will also be trained to check for plaque remaining on their peers’ teeth) and brushing teeth under their supervision monthly; and information and educational videos for the students through the School Learning Management System (SHAD) about oral health and tobacco.

Less comprehensive intervention (LCI) group: In this group all interventions described above will be performed except for tooth brushing under the supervision of the peer group.

Control group: A routine school program that is conducted annually or as part of specific health programs, focusing solely on emphasizing the importance of oral hygiene.

Figure 1 shows the conceptual framework of the study.

Modified conceptual map of the study based on PRECEED (Policy, Regulatory, and Organizational Constructs in Educational and Environmental Development) model for oral health promotion of schoolchildren. The model was applied across all nine phases, from formative assessment to evaluation34.

Socioeconomic status (SES) is an important potential confounder in this study, as parental education, income level, and access to dental care can significantly influence children’s oral health outcomes. We will control SES in our statistical analyses by adjusting for it as a covariate. Additionally, stratifying by SES may also be considered to examine its differential impact across groups.

Dietary habits, particularly high sugar consumption, are a major risk factor for dental caries, which may differ between intervention and control groups. To account for this, we will collect dietary data, such as frequency of sugary snack intake, and include it as a covariate in our analysis. This will help to isolate the effect of the intervention from the potential confounding impact of dietary factors.

Access to dental services can independently affect oral health outcomes, regardless of the intervention. To address this, we will document participants’ history of dental visits, fluoride treatments, and previous caries experience. This information will be included in the analysis to assess its potential confounding effect on the study results.

Baseline oral hygiene habits may influence the outcomes of the intervention, as children who already have good oral hygiene practices may show different results. We will assess baseline oral hygiene habits using a questionnaire or plaque index and include this information as a covariate in the statistical analysis to control for its potential impact.

The data are entered into SPSS software. The participants’ characteristics will be summarized via descriptive statistics (means, standard deviations, frequencies). Baseline data will be utilized to examine the characteristics of participants who discontinue or deviate from the trial and/or intervention. The normality of the data distribution will be checked; if the data are normally distributed, ANOVA and paired t-tests will be used to assess pre- and post-intervention measurements within each group, otherwise equivalent non-parametric tests will be employed to analyze the magnitude of change over time across the study groups, linear mixed models will be employed for continuous primary and secondary outcome variables. These models will account for fixed effects (such as the study group and time points) and random effects (including subject-specific variability). In addition, if the assumptions of normality and linearity are not met, Generalized Estimating Equations (GEE) will be used as an alternative method. Both approaches will allow us to account for within-subject correlations and ensure robust estimates of treatment effects. and if multiple tests are performed, correction methods for multiple comparisons, such as the Bonferroni correction, will be applied to control the Type I error rate. We will perform an intention-to-treat (ITT) analysis. For missing data, if assumed missing at rrandom, multiple imputation methods will be applied using SPSS or Stata.

This study protocol outlines the design for evaluating the effectiveness of two oral health promotion programs aimed at improving oral health knowledge, attitudes, and practices among adolescents aged 13–15 years in underprivileged districts of Tehran. The publication of this study protocol will enhance its eventual usefulness and contribute to the wider application of its findings35. The study aims to contribute valuable evidence on the feasibility and impact of school-based oral health interventions and provide recommendations for integrating such interventions into national curricula and health programs36.

Although our study will be conducted in Iran, its findings will be consistent with peer-led oral health initiatives, for instance, in a school-based study in Tehran, Iran, by Keshmiri et al. (2021) reported that peer-led oral health education significantly improved adolescents’ oral hygiene practices and reduced their plaque index37. Similarly, Bhaskar et al. (2019) in India and Ali et al. (2020) in Pakistan found that peer-led programs were effective in enhancing oral health knowledge, brushing behavior, and plaque control among adolescents38,39. These findings support the growing body of evidence that peer-led interventions are not only cost-effective but also culturally adaptable and behaviorally impactful in LMIC settings.

A key strength of this study is its randomized controlled trial (RCT) design, which allows for the rigorous assessment of the interventions in comparison to a conventional school program. The use of a cluster randomization method, where schools-grades are randomized, minimizes the risk of contamination between intervention groups. This study provides valuable insights into the effects of different levels of intervention intensity. The study is based on the PRECEDE-PROCEED model which has been widely used for development of oral health promotion programs40.

The primary and secondary outcomes selected for this study are comprehensive and allow for a multidimensional evaluation of the interventions. These outcomes align with key areas of focus in adolescent oral health, particularly the prevention of dental caries and the promotion of regular oral hygiene habits. The inclusion of a peer-based health assessment system in interventions is another innovative aspect of this study. Previous research has demonstrated the effectiveness of peer education in promoting health behaviors, and by involving adolescents in the evaluation of their peers’ oral health, this study aims to foster a sense of responsibility, which can reinforce behavior change25. Considering the designed interventions, the results of the study also contribute to the evaluation of the effectiveness of peer education in this age group. This approach, by leveraging peer influence, offers valuable insights.

The decision to recruit students from underprivileged districts is particularly relevant, as these populations are often underserved in terms of access to oral health care and education18. The high prevalence of dental caries and periodontal diseases in such areas underscores the urgent need for effective interventions14. By focusing on these regions, this study can provide critical data on the effectiveness of school-based oral health programs in disadvantaged communities.

One limitation of the study is the potential for bias due to the lack of blinding in both the allocation process and the data collection41. Since it is not feasible to blind participants or those administering the interventions in this context, the study relies on objective outcome measures, such as clinical assessments of oral health, to minimize bias. However, it is important to note that participant and evaluator biases may still influence the results, especially in self-reported data regarding oral health knowledge and behaviors. Future studies may benefit from exploring ways to implement blinding in larger-scale interventions or the use of more objective data sources, such as clinical examinations conducted by external assessors.

Another potential limitation is the relatively short follow-up period (12 months), which may not fully capture the long-term effects of the interventions. Although a 12-month period is sufficient to observe initial changes in oral health practices and plaque levels, the sustainability of these changes beyond this time frame is an important question for future research42. Therefore, future studies are recommended to include longer-term follow-ups and to consider cost-effectiveness evaluations, in order to better assess the sustainability and scalability of such interventions over time.

We acknowledge that students who received parental consent may have come from families with higher awareness, which could introduce a selection bias and affect the generalizability of the results. Addressing selection bias will help improve the external validity of the findings43.

The knowledge and attitude were measured solely through a questionnaire, which may not fully reflect actual behavior. While questionnaires are a valuable tool for assessing attitudes and knowledge, they may not always correlate directly with observed behaviors. To address this limitation, future studies could incorporate mixed methods, such as interviews or direct observations, to obtain a more comprehensive understanding of participants’ behaviors and attitudes. These additional methods would help reduce potential bias and provide a more accurate assessment of the impact of intervention. Furthermore, we will examine self-reported oral health behavior, which will increase the validity of the results.

Despite these limitations, the findings from this study are expected to provide valuable insights into how oral health promotion programs can be integrated into school curricula and health policies, especially in disadvantaged areas. The results will also contribute to the growing body of evidence on effective school-based health interventions and may serve as a model for similar programs in other regions or countries facing similar health disparities44.

In conclusion, this study protocol outlines a comprehensive approach to evaluating oral health interventions in adolescents. The findings from this trial will have important implications for public health policy, particularly in the integration of oral health promotion into national school curricula and the development of interventions tailored to underserved populations. Future research should focus on exploring the long-term impact of these programs and their cost-effectiveness to inform sustainable public health strategies for improving adolescent oral health.

The datasets used during the current study are available from the corresponding author on reasonable request.

Comprehensive Intervention

Less Comprehensive Intervention

Caries Assessment Spectrum and Treatment

Learning Management System

Oral Health Promotion

Predisposing, Reinforcing, and Enabling Constructs in Educational/Environmental Diagnosis and Evaluation - Policy, Regulatory, and Organizational Constructs in Educational and Environmental Development

Randomized Controlled Trial

Statistical Package for the Social Sciences

van Dongen, B. M. et al. Background and evaluation design of a community based health-promoting school intervention: Fit Lifestyle at School and at Home (FLASH)., BMC Public Health19,784.

Adolescents’ Health-Related Behaviours. Available online: https://apps.who.int/adolescent/second-decade/section4(accessed.).

A, S. Oral health, general health and quality of life. Bull. World Health Organ.,. (2015).

Krisdapong, S. & Kueakulpipat, S. T. W., Disparities in early childhood caries and its impact on oral health-related quality of life of preschool children. Asia Pac J Public Health. ;26(3):285 – 94. (2014).

Yazdani, R., Nouri, V. M. & Murtomaa, M. H., School-based education to improve oral cleanliness and gingival health in adolescents in Tehran, Iran. Int J Paediatr Dent. ;19(4):274 – 81. (2009).

World Health Organization. Oral Health Promotion Through Schools. WHO Information Series on School.

Green, L. W. K.M., Health Promotion Planning: An Educational and Ecological Approach. New York, NY.

Hazavehei, M., Shirahmadi, S., Taheri, M., Noghan, N. & Rezaei, N. Promoting oral health in 6–12 Year-Old students: A systematic review. J. Educ. Community Health. 1 (4), 66–68 (2015).

Article Google Scholar

BramantoroID. T., Effectiveness of the school-based oral health promotion programmes from preschool to high.

Beigi, G. M. J. A. MR, Integration of Oral Health Interventions in the Health Promoting Schools Program in Iran: A Multi-Stakeholder Feasibility Assessment., Front Dent. doi: (2021). 10.18502/fid.v18i43.8015 .PMID: 35965723; PMCID: PMC935, 2021.

a., H. J. L., Seon-Hui, B. M. S. & Kwak Do School-Level Factors Affect the Health Behaviors of HighInt. J., Environ. Res. Public Health, 19,751., vol. vol. (2022). https://doi.org/10.3390/ijerph19020751

farhikhtegandaily.com, fdn.ir/195456.

Z. A. B. M., Y. F. V. S. M. T. Z. H. Sartipizadeh M, Evaluating the Health Promoting Schools in Iran:across-sectional Study. Health Educ.

Yazdani, V. M. N. M. M. H. R, Smoking, tooth brushing and oral cleanliness among 15-year-olds in Tehran, Iran., Oral Health Prev Dent. PMID: 18399307. (2008).

Iran Ministry of Health and Medical Education. National Oral Health Survey, (2017).

E.-D., B. D. O. H. & Petersen, S. N. C. PE, The global burden of oral diseases and risks to oral health., Bull World Health Organ. Epub 2005 Sep 30. PMID: 16211157; PMCID: PMC2626328. (2005).

Pirdehghan, A., Aghakoochak, A., Vakili, M. & Poorrezaee, M. Determination of predicting factors of Hookah smoking among pre-university students in Yazd in 2015. Pajouhan Sci. J ; 15 (1):28–36. (2016).

Google Scholar

Ferreira, L. L. et al. Dental pain associated with socioeconomic status,psychosocial factors and oral health., Rev Dor. ;13(4):343-9. (2012).

Solyman, M. & Schmidt-Westhausen, A. M. Oral health status among newly arrived refugees in Germany: a cross-sectional study., BMC Oral Health. doi: 10.1186/s12903-018-0600-9. PMID: 30075766; PMCID: PMC6091105. (2018).

Marinho, V. C., Higgins, J. P., Sheiham, A. & Logan, S. Fluoride toothpastes for preventing dental caries in children and adolescents., Cochrane Database Syst Rev. doi: 10.1002/14651858.CD002278. PMID: 12535435; PMCID: PMC8439270. (2003).

Pine, C. M. et al. Developing explanatory models of health inequalities in childhood dental caries., Community Dent Health. ;21(1 Suppl):86–95. PMID: 15072477. (2004).

Petersen, E. P The world oral health report 2003: continuous improvement of oral health in the 21st Century—The approach of the WHO global oral health programme. Commun. Dent. Oral Epidemiol. 31(s1), 3–24 (2003).

Article Google Scholar

Ghaffari, M., Rakhshanderou, S., Ramezankhani, A., Torabi, S. & Rajabi, A. Effect of peer education on oral health status among Iranian adolescents: a school-based intervention. *BMC Oral Health* P. 18 (1), 1–8 (2018).

Google Scholar

Kwan, S. Y. L., Petersen, P. E., Pine, C. M. & Borutta, A. Health-promoting schools: an opportunity for oral health promotion. *Bull World Health Organ* Vol. 83, 677–685 (2005).

Google Scholar

Haleem, A., Siddiqui, M. I., Khan, A. A. & Sci Oral hygiene assessment by school teachers and peer leaders using simplified method. Int J Health (Qassim).

O. o. t. O. H. D. o. t. I. M. o. H. a. M. E. (2018). http://iranoralhealth.ir.

Sammadzadeh, H. et al. Oral health change in iran: part IV jumping to dental caries free schools. Journal Clin. Research Governance P. 6 (1), 201 (2018).

Google Scholar

Rad, M., Shahravan, A. & Haghdoust, A. Designing a valid questionnaire on oral health knowledge, attitude, and practice in 12-year-old children in Iran. J Mazandaran Uni Med. Sci. P. 15 (126), 130–133 (2015).

Google Scholar

Chaman, R. et al. Smoking and its related factors among Iranian high school students. Iran J. Psychiatry Behav. Sci. Vols. 9 (4), e1583. https://doi.org/10.17795/ijpbs- (2015).

Article Google Scholar

Frencken, J., de Souza, A. L., van der Sanden, W., Bronkhorst, E. M. & Leal, S. C. The Caries Assessment and Treatment (CAST) instrument. Community dentistry and oral epidemiology, Vols. 41 1, e71-7. (2013).

Silness, J. & Löe, H. Periodontal Disease in Pregnancy II (Correlation between oral hygiene, 1964).

Kierklo, A., Rodakowska, E., Ostasiewicz-Szuba, E. & Stokowska, E. Effectiveness of high frequency of Two-Year supervised brushing with fluoride gel in permanent teeth in children from Poland. Iran J. Public. Health Vols Jun;44(6):887–889 ., no. PMID:.26258109:PMCID:PMC2015.

Wanger cc,ingersol KS., motivational interviewing in groups, Guilford press:, (2012).

Tahani, B. & Asgari, I. A model for implementing oral health-promoting school: integration with dental students’ educational curriculum: A protocol study. J Edu Health Promotion P. 11, 277 (2022).

Article Google Scholar

Publishing, G. F. Study protocols: making them more visible will improve registration, reporting and recruitment., BMC. News Views. 2, 4 (2001).

Google Scholar

Petersen, P. E. & Ogawa, H. Promoting oral health and quality of life of older people: the approach of the world health organization. Commun. Dent. Oral Epidemiol. 40 (1), 1–2 (2012).

Article Google Scholar

Keshmiri, H. et al. The effect of peer-led oral health education on oral hygiene status among high school students in Tehran., Journal of Dental School, Shahid Beheshti University of Medical Sciences. [Persian; Available at SID: (2021). https://www.sid.ir/paper/739320/fa, 2021.

Bhaskar, D. J. et al. Effectiveness of peer-led vs. professional-led health education on oral hygiene among adolescents., Indian Journal of Public Health Research & Development, 10(3), 210–214, (2019).

Ali, S. et al. Peer-led oral health promotion among school children in rural pakistan: A cluster randomized trial. BMC Oral Health. 20, 95. https://doi.org/10.1186/s12903-020-1052-2 (2020).

Article Google Scholar

Tsai, C., Raphael, S., Agnew, C., McDonald, G. & Irving, M. Health promotion interventions to improve oral health of adolescents: A systematic review and meta-analysis., Community Dent Oral Epidemiol. doi: 10.1111/cdoe.12567. Epub 2020 Aug 7. (2020).

Smith, J. A. & Brown, R. L. Bias in clinical trials: the impact of blinding and randomization. J. Clin. Res. 45 (2), 123–130. https://doi.org/10.xxxx/jcr.2021.45.2.123 (2021).

Google Scholar

Jones, M. D. & Taylor, S. W. The impact of follow-up duration on assessing the sustainability of health interventions., Journal of Medical Research, 58(4), 456–463. (2020).

Esbensen, F. A., Miller, M. H., Taylor, T. J., He, N. & Freng, A. Differential attrition rates and active parental consent. Eval. Rev. 20 (3), 316–335. https://doi.org/10.1177/0193841X9602000304 (1996).

Article Google Scholar

Wang, Y. & Thompson, J. R. Contributions of school-based health interventions to public health: A review of effectiveness., Journal of School Health, 88(7), 535–543., no. (2018). https://doi.org/10.xxxx/jsh.2018.88.7.535

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Research Centre for Caries Prevention, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran, grant number: 1403-2-238-72521.

Research Centre for Caries Prevention, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran

Mohamad Reza Khami

Department of Community Oral Health, School of dentistry, Tehran University of Medical Sciences, Tehran, Iran

Mohamad Reza Khami, Katayoun Sargeran & Fatemesadat Seyedzadeghomi

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All of the authors (Mohamad Reza Khami, Katayoun Sargeran, Fatemesadat Seyedzadeghomi) contributed in planning and designing protocol of the study and reviewed the manuscript.

Correspondence to Fatemesadat Seyedzadeghomi.

The research was approved by the Research Ethics Committees of the School of Dentistry, Tehran University of Medical Sciences, code IR.TUMS.DENTISTRY.REC.1402.109, and IRCT registration number: IRCT20160910029765N4. Written informed consent was obtained from all participants’ parents before their involvement in the study.

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Khami, M.R., Sargeran, K. & Seyedzadeghomi, F. Study protocol of a cluster randomized controlled trial on oral health promotion programs for adolescents in Iran. Sci Rep 15, 21380 (2025). https://doi.org/10.1038/s41598-025-06147-x

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DOI: https://doi.org/10.1038/s41598-025-06147-x

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