The MI-intervention is used as a part of normal dental hygienist appointment. Dental hygienists are trained to focus on patients view of their oral health, self-care skills and need for oral-health related behaviour change. They are supposed to use open-ended questions, reflective listening and reinforcing with patients. Dental hygienist support patients in decision making although patients were addressed as an active agent.

In control group prevailing, more professional-centered education is used. Dental hygienist define patients educational needs and give direct instructions how to change behaviour and self-care.

In intervention group dental hygienists are trained to focus on patients view of their oral health, self-care skills and need for oral-health related behaviour change. They are supposed to use open-ended questions, reflective listening and reinforcing with patients.

In control croup dental hygienist defined patients educational needs and gave direct instructions how to change behaviour and self-care.

Change in BoP is measured three times during the study. In the baseline and in the tree- and six-months follow-up.

Bop is recorded60 seconds after the pocket probing and assessed as present (1) or absent (0) on four surfaces.

Change in PD is measured three times during the study. In the baseline and in the tree- and six-months follow-up. PD is measured at mesial, distal, lingual and buccal surfaces.

Change in CAL is measured three times during the study. In the baseline and in the tree- and six-months follow-up. CAL is measured if cemento-enamel junction is uncovered or if there is 6 mm deep or deeper gingival pocket.