The aim of this study was to evaluate if a mass media campaign regarding periodontal disease could increase the knowledge in the general population of diagnoses, symptoms and treatment options of periodontal disease. More specifically, the aim was to investigate the number of correct answers to knowledge questions before and after the campaign. The Swedish Association of Periodontology conducted the campaign through brochures, newspapers, radio and TV. The effect of the campaign was evaluated by a pre- and post campaign questionnaire with a cohort design. From a national population register of 50-75 year olds in Sweden, 900 persons were randomly sampled for the study. A total of 64% of the sample answered both questionnaires. The result of the study showed an improvement among the respondents. There was a significant increase in the number of correct answers regarding diagnoses, symptoms and treatments of periodontitis. In the questionnaire, correct answers regarding "Mobile teeth" increased from 57% to 65% (p=0.003) and "careful dental hygiene" from 65% to 73% (p=0.001). Kappa value's were calculated for consistency in the reply and all kappa values were low especially for the questions "X-ray" (0.36) and "Cleaning between the teeth" (0.38). It was concluded that the campaign probably was successful from a public health knowledge standpoint.

The aim of this study was to investigate changes in knowledge before and after a mass media campaign, in relation to social attributes, care system attributes and oral health aspects. The study was based on a questionnaire in a cohort design, sent out to 900 randomly sampled people aged 50–75 in Sweden. The response rate to the questionnaire before and after the campaign was 70% and 65% respectively. Sixty-four percent answered both questionnaires. Two questions addressed knowledge, while 10 questions aimed to measure social attributes, care system attributes and oral health aspects. Data were analysed for bivariate relations as to change in knowledge and social attributes, care system attributes and oral health aspects. Data were also analysed in multiple regression analysis with knowledge before, knowledge after and knowledge differences as dependent variables. The results showed that there were a number of independent variables with influence on the dependent variables. Of the social attributes, secondary education gave almost 10% (P< 0.001) better knowledge both before and after the campaign. Among care system attributes, high care utilization was related to knowledge both before and after the campaign. The most important factors for knowledge about periodontitis were education, care utilization and perceived importance of oral health. In conclusion, this study demonstrates that mass media might increase knowledge about periodontitis as a health promotion strategy.