Objectives: Based on the 7th National Health and Nutrition Examination Survey 1,135 adults aged 19 years were selected as the final study subjects to investigate the relationship between oral health and chewing difficulty in adults. Methods: Frequency analysis, chi-square test, and logistic regression analysis were performed for general characteristics, oral health behaviors, awareness symptoms, and oral health using SPSS Program 21.0. Results: Regarding factors related to chewing difficulty, the oral health was 0.44 times lower than the average level and 0.28 times lower than the good condition. In the case of oral examination, chewing difficulty was 0.85 times lower. The speaking problem was 0.11 times lower in usually than inconvenient and 0.06 times lower in not inconvenient. In the case of un-treatment, it was 0.40 times lower than that in the case of treatment.
The chewing difficulty was significantly higher by 2.09 times in the case of experience of tooth pain and 1.36 times in the case of periodontal disease. Conclusions: Based on the above results, it is thought that prevention and treatment are actively needed to identify factors of oral health to improve oral health, to solve chewing difficulty and to improve chewing function.