The present study was a randomized control trial to test an intervention emanating from the Client Self-care Commitment Model (CSCCM), to encourage patients to increase their responsibility for their oral self-care. A total of 75 individuals were re-examined 1-2 years after their initial therapy at the Department of Periodontology, Uppsala County Council, Sweden. Patients who exhibited insufficient compliance, 37 individuals, were included in a randomized single-blind control trial to test an intervention based on the CSCCM. Patients were examined at baseline and 3 months after hygiene treatment. The results demonstrated that patients in the intervention (IV) group increased their interdental cleaning and reduced their plaque index significantly compared with the control group. The former also reduced the number of periodontal pockets >4 mm significantly from baseline until after the hygiene treatment. The majority of the individuals in the IV group reported that the written commitment had influenced on their oral self-care habits in a positive direction. The CSCCM enhanced the client participation in the treatment process and improved the compliance and oral self-care behaviours. In addition, the model contributed to a reduction in periodontal pockets.