Age-stratified associations of oral hygiene care with dental caries and periodontal disease: Analysis of Seventh Korea National Health and Nutrition Examination Survey

Objectives: This study aimed to demonstrate the association between oral hygiene care behavior, such as tooth brushing or interproximal cleaning, and leading causes of tooth loss, including caries and periodontal disease, stratified by age. Methods: Representative data from the Korea National Health and Nutrition Examination Survey during 2016–2018 (KNHANES VII) was used to evaluate the association between tooth brushing frequency per day (TBF) along with interproximal cleaning (IC) with dental floss or interdental brush and tooth caries or periodontal disease as stratified by three age groups (14 or 19–39 years, 40–59 years, and 60 years or over). Finally, 12,867 individuals aged 14 years or older for caries, and 11,290 people aged 19 years or older for periodontal disease were analyzed. Results: TBF of 1 time or less was significantly associated with tooth caries in the 14-39 year-age group with the largest effect size (OR: 2.27; 95% CI: 1.63-3.15). However, the effect size of TBF on caries decreased with age, and it was not significant for individuals aged 60 years or older. TBF did not show a significant effect on periodontal disease across all age groups. Interdental cleaning (IC) was consistently associated with tooth caries across all age groups with ORs from 1.33 to 1.26. IC was also effective in reducing periodontal disease, except for those 60 years or older (OR: 1.42,1.32; 95% CI: 1.06-1.89, 1.13-1.56). Conclusion: The association of TBF and IC in preventing dental caries and periodontal disease differed by age. Young or middle-aged individuals might benefit from frequent toothbrushing and IC to prevent caries and periodontal disease, while older adults might require additional approaches as well as IC and frequent toothbrushing.