Background Young adults are exposed to a variety of risk-related behaviours such as alcohol, smoking, and changes in dietary habits, which may result in unknown outcomes in their oral health. There is limited evidence on whether different risk behaviours are associated with oral health behaviours in the university student population. This study gathers data on the behaviours of students in their first year of university, which will inform the future development of oral health behaviour change interventions for this population. Method This longitudinal quantitative survey involved 205 first-year university students, aged 18-24. They completed questionnaires at baseline and a 6-month follow-up interval providing information regarding self-reported oral health status, hygiene routines, risk behaviours (e.g., diet, smoking, alcohol) and attitudes towards digital health. Results The findings show associations between oral health behaviours with risk behaviours including links with oral care routines, bleeding gums, brushing frequency, with exercise, vaping, and unhealthy food and drink intake. Significant changes over the two-time points were also observed, such as the worsening of the self-reported condition of the teeth (p<0.001), reduction in the self-reported condition of the gums (p=0.004), reduced brushing frequency (p=0.003), less regular dental visits (p=0.013), more students intending to visit their previous dentist rather than finding a new dentist at university (p=0.026), and increased consumption of unhealthy non-alcoholic drinks (p=0.003). Positive changes over time include reduced alcohol consumption frequency and units (p=0.030 and p=0.001), fewer instances of binge drinking (p=0.014), and less frequent consumption of unhealthy foods (p=0.034). Conclusion The findings highlight the complex relationship between oral heal and risk behaviours in this demographic. Poorer oral health behaviours are linked to engagement in risk behaviours. Therefore, oral health behaviours should be targeted alongside other risk behaviours. Tailored interventions should be developed to improve oral health and behaviour among university students.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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The study received ethical approval from the University of Manchester Ethics Committee (Reference: 2023-13950-27733). Informed written consent was obtained from participants involved in this study.

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