Prevalence of periodontitis based on the 2017 classification in a Norwegian population: The HUNT study

Aim This cross-sectional study assesses the prevalence of periodontitis in a large Norwegian population, based on the 2017 World Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions. The prevalence of periodontitis was determined by bone loss recorded on radiographs (orthopantomogram [OPG] and bitewing [BW]) and by clinical examination. Materials and methods As part of a large population health study (The HUNT Study), 7347 participants aged 19 years and older were invited to the HUNT4 Oral Health Study. Radiographic bone loss (RBL) and periodontal stage and grade were assessed in 4863 participants. Results Periodontal examination was performed in 4863 participants. RBL and clinical registrations corresponding to periodontitis as defined were observed in 72.4%. The prevalence of periodontitis increased after 40 years of age, with severe forms occurring primarily after 60 years of age. Stage I was observed in 13.8%, Stage II in 41.1%, Stage III in 15.3%, and Stage IV in 2.3% of the population. Grade A, B, and C was observed in 5.7%, 60.2%, and 6.2%, respectively. Conclusion Periodontitis was frequently observed in the investigated population. The prevalence of periodontitis Stage III and Stage IV combined was observed in 17.6% of the study population.