Effects of periodontal treatment on periodontal status in Finland: a register-based study.

Objective: This register-based follow-up study investigated periodontal status after periodontal treatment (PT) based on need following oral health examination (OHE).

Materials and methods: A total of 42,533 adults aged 18-89 years receiving OHE in the public oral health clinics of the City of Helsinki in 2009 were included. Dentists recorded periodontal status by the Community Periodontal Index (CPI), and determined the individual recall interval (IRI). Follow-up OHE between 2010 and 2015 was performed for 16,040 adults based on IRI or later. Outcome of interest was change of CPI during follow-up and was modelled with proportional odds model for each sextant separately. Results were reported as odds ratios (ORs).

Results: Signs of periodontal disease were present in 95% of the study population. Symptoms of periodontitis (CPI score 3 or 4) were observed in 24% of patients. In models, PT indicated better outcome in all six sextants and in sextant 5 after one treatment (OR 5.05, 95% confidence interval [CI] 4.53-5.63). A poorer outcome was observed in patients with diabetes or severe mental disorders and in men.

Conclusions: The study population had a high prevalence of periodontal diseases. Men and patients with diabetes or severe mental disorders should be specifically targeted by dentists.