Introduction: Dentists by their professional knowledge of prevention have a key role in providing a positive role model for oral health-promoting behaviours. We aimed to investigate the health behaviour of Iranian senior dental students in terms of oral self-care and tobacco use during a 10-year period to assess their preparedness to act as role models for health-promoting behaviours.

Materials and methods: The study was performed in six dental schools selected through stratified cluster random sampling to have a representative sample of all dental schools in Iran. Data were collected in four occasions in 2005, 2008, 2011 and 2015. Senior dental students (N = 1188) were invited to voluntarily complete a self-administered anonymous questionnaire about their oral self-care and tobacco use. Recommended tooth-brushing habit (RTH) was defined as at least twice a day brushing with fluoridated toothpaste. Three separate questions about cigarette, pipe and waterpipe use were applied to assess the students' reported use of tobacco.

Results: The response rate was 81%. Female students reported more frequently RTH than males (p < .001). The reported RTH was more prevalent among nonsmokers. In 2005, 2008, 2011 and 2015, 22.5%, 26%, 28.5% and 24.6% of the students reported smoking, respectively. The trend of reported smoking had the least variation among female students. This was true also for male students regarding RTH.

Conclusion: The status and trend of oral self-care and tobacco use among Iranian dental students call for more emphasis on adopting health-promoting behaviours during dental education.