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

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