Purpose: Although poor oral hygiene practices can have serious health consequences, a large number of adults brush or floss their teeth less than the recommended time or not at all. This study examined the mediating effect of two key self-regulatory processes, self-efficacy and planning, as the mechanisms that translate dental flossing intentions into behavior. Method: Participants (N = 629) comprised young adults attending a major university in Queensland, Australia. A longitudinal design guided by sound theory was adopted to investigate the sequential mediation chain for the effect of dental flossing intentions (time 1) on behavior (time 3) via self-efficacy and planning (time 2). Results: A latent variable structural equation model with standardized parameter estimates revealed the model was a good fit to the data. Controlling for baseline flossing, the effect of intentions on behavior was mediated via self-efficacy and planning, with 64 % of the flossing variance accounted for by this set of predictors. Controlling for age and sex did not change the results. Concluson: The results extend previous research to further elucidate the mechanisms that help to translate oral hygiene intentions into behavior and make a significant contribution to the cumulative empirical evidence about self-regulatory components in health behavior change.