Determinants of oral hygiene behaviour among patients with moderate and severe chronic periodontitis based on the theory of planned behaviour

Objectives Health interventions based on cognitive theories effectively bring about behaviour change. Therefore, the present study aimed to assess the determinants of oral hygiene behaviour (OHB) based on the theory of planned behaviour (TPB) among patients with moderate and severe periodontitis. Methods A cross-sectional study was conducted using a 47-item self-report questionnaire to evaluate oral health knowledge (OHK), expected social outcomes (ESO) and OHB based on the variables of TPB [attitude (ATT), social norms (SN) and perceived behavioural control (PBC)] of patients with moderate and severe periodontitis. Analysis of variance was used for comparison between the parameters. Regression analyses identified the significant determinants of OHB. Results A total of 543 patients meeting the inclusion criteria were included. ESO (B = 0.04) and OHK (B = 0.14) significantly predicted intention to perform OHB. None of the TPB variables significantly predicted OHB. Apart from ESO and OHK, which were significant predictors for both genders, ATT (beta = 0.22) additionally predicted OHB among men. Also, for university graduates, ESO (beta = 0.13) and OHK (beta = 0.17) significantly predicted OHB. Lastly, OHB showed a significant and positive correlation with all the parameters (P < 0.05). Conclusion The study concludes that the TPB model facilitates the evaluation of psychosocial determinants of OHB among patients with periodontitis. Also, a significant relationship between gender, OHB and variables of TPB further highlights the importance of patient-focused preventive oral health care education.