Journal of Clinical Periodontology

Factors influencing oral hygiene behaviour and gingival outcomes 3 and 12 months after initial periodontal treatment: an exploratory test of an extended Theory of Reasoned Action


  • Conflict of interest and source of funding statement

  • The authors declare that there are no conflicts of interest in this study. The study was supported by Swedish Research Council, Uppsala County Council, Swedish Patent Revenue Fund for Research in Preventive Odontology, and the support of the authors’ institutions.


Birgitta Jönsson

School of Health and Social Studies

Dalarna University

SE-791 88 Falun, Sweden




The aim was to empirically test the extended Theory of Reasoned Action (TRA) and the prospective direct and indirect role of attitudes, beliefs, subjective norms, self-efficacy, and a cognitive behavioural intervention in adult's oral hygiene behaviour and gingival outcomes at 3- and 12-month follow-up.

Materials and Methods

Data were derived from an RCT evaluating the effectiveness of oral hygiene educational programs integrated in non-surgical periodontal treatment (n = 113). Before baseline examination, participants completed a self-report questionnaire. Structural equation modelling using maximum likelihood estimation with bootstrapping was used to test the direct and indirect (mediated) pathways within the extended TRA model.


The extended TRA model explained a large amount of variance in gingival outcome scores at 12 months (56%). A higher level of self-efficacy at baseline was associated with higher frequencies of oral hygiene behaviour at 3 months. Being female was linked to more normative beliefs that, in turn, related to greater behavioural beliefs and self-efficacy. Gender was also related to behavioural beliefs, attitudes and subjective norms. Both frequency of oral hygiene behaviour at 3 months and the cognitive behavioural intervention predicted gingival outcome at 12 months.


The model demonstrated that self-efficacy, gender and a cognitive behavioural intervention were important predictors of oral hygiene behavioural change.