Risk factors for tooth loss over 3 years according to the number of pre-existing teeth: data from a rural cohort / 대한구강보건학회지

ABSTRACT

OBJECTIVES: The aim of this study was to identify the risk factors for tooth loss over three years, according to the number of pre-existing teeth, in middle and old aged people in a rural area. METHODS: This was a 3-year follow-up study including participants from KoGES-ARIRANG. Eight-hundred and fifty-five participants took part in both initial and follow-up oral examinations and surveys, conducted between 2010 and 2016. The number of existing teeth was determined through oral examination, and the subjects' sociodemographic characteristics, subjective periodontal statuses, and oral health behaviors were identified through oral questionnaires via 11 interviews. Chi-square analysis was used to compare tooth loss in participants with less than 20 pre-existing teeth to tooth loss in those with 20 or more pre-existing teeth. Multivariate logistic regression analyses were used to identify risk factors for tooth loss. RESULTS: Four-hundred and thirty-nine (51.4%) subjects lost more than one tooth over three years. After adjusting for demographic characteristics, subjective periodontal statuses, and oral health behaviors in subjects with 20 or more pre-existing teeth, the odds for tooth loss were as follows 2.11 (1.42-3.14) times higher in people aged over 65 years compared to less than 65 years, 1.59 (1.06-2.38) times higher in those with a low (below elementary school) compared to high educational level, and 2.01 (1.33-3.02) times higher in those with a severe compared to normal subjective periodontal status. CONCLUSIONS: The risk of tooth loss was different in subjects with less than 20 pre-existing teeth compared to those with 20 or more pre-existing teeth. Therefore, the approach to prevent tooth loss should be different depending on the number of teeth present.