September 2018

Objective: This study aimed to investigate the level of oral health behaviours (OHB) and oral health-related dietary behaviours (OHD-B) and to find out their relationship and their determinants among a relatively large sample of university students. Research design and participants: In a cross-sectional study, 535 Iranian university students were selected in order to investigate their OHB and OHD-B through a self-administrated questionnaire. Main outcome measures: Tooth brushing, flossing, use of fluoride toothpaste, and sugary snacking collected data on OHB. Consumption frequency of 16 common cariogenic and non-cariogenic foodstuffs was used for evaluation of OHD-B. Latent class analysis (LCA) and latent class regression (LCR) were applied to identify classes of OHB and OHD-B and their potential determinants, respectively. ANOVA, Chi-square and Spearman’s correlation were used. Results: In total, 49.7% and 53.2% of participants had good OHB and OHD-B, respectively. The results of LCR indicated that female gender (OR: 8.22, 95% CI: 3.42-19.72), higher age (OR: 1.39, 95% CI: 1.04-1.85), doctorate level (OR: 6.99, 95% CI: 2.22-21.98), and being single (OR: 3.54, 95% CI: 1.36-9.19) were related to good OHB. Furthermore, LCR analysis showed that students who lived with their families had greater chance for having good OHD-B (OR: 3.01, 95% CI: 2.00-4.53). Students with good OHD-B reported brushing and flossing their teeth more frequently than those with poor OHD-B (P<0.05). Conclusions: The shortage of favourable oral health behaviours among university students highlights the importance of planning oral health programs to improve their oral health, especially their dietary behaviours. Key words: Oral health, health behaviours, diet, sociodemographic determinants