Periodontitis is a chronic inflammatory disease in which long-term treatment success depends greatly on patients' adherence to oral hygiene practices and periodontal therapy. Psychological factors such as oral hygiene-related self-efficacy and illness perception may influence patients' motivation and ability to maintain effective plaque control and attend follow-up visits. However, limited evidence exists regarding the impact of behavioural interventions on adherence and clinical outcomes in periodontal therapy.

This randomized controlled trial aims to evaluate the effect of an behavioural intervention on treatment adherence and clinical periodontal outcomes in patients with Stage I-III periodontitis having low oral hygiene-related self-efficacy. A total of 78 participants will be randomized into test and control groups. Both groups will receive Step 1 and 2 periodontal therapy, including professional mechanical plaque removal and risk factor control. The test group will additionally receive a self-efficacy-based behavioural intervention while the control group will receive conventional oral hygiene instructions.

Clinical periodontal parameters including Turesky modification of Quigley-Hein Plaque Index (TQHI), Full Mouth Bleeding Score (FMBS), probing pocket depth (PPD), and clinical attachment level (CAL) will be assessed at baseline, 8 weeks, and 6 months. Oral hygiene self-efficacy and illness perception will also be evaluated using validated questionnaires. The primary outcomes will be treatment adherence and treatment response at 6 months. The study aims to determine whether a self-efficacy-based behavioural approach can improve adherence and enhance periodontal treatment outcomes.

Inclusion Criteria:

1. Inclusion criteria at the patient level, age ≥ 18 years
2. According to the 2017 EFP/AAP classification, patients with periodontitis stage I-III, with low self-efficacy will be included
3. According to American Society of Anaesthesiologists Physical Status classification P1 and P2 will be included.

Exclusion Criteria:

• Patients will be excluded from the study if they have any of the following characteristics

  1. According to American Society of Anesthesiologists Physical Status classification P3 and P4 will be excluded.
  2. Use of antibiotics within 6 months prior to the study
  3. Xerostomia
  4. Physical inability to perform oral hygiene procedures
  5. Use of drugs influencing gingival hyperplasia or bleeding.
  6. Presence of an acute condition requiring emergency dental treatment
  7. Any periodontal treatment in the past 1 year