Improving oral hygiene may attenuate occurrence of head and neck cancer: nation-wide population based cohort study.

Abstract

Background: In previous case-control and cross-sectional studies, less frequent dental visits, infrequent tooth brushing, presence of periodontal disease, and increased number of tooth loss were shown to be associated with increased risk of head and neck cancer. However, studies regarding the association of periodontal disease and parameters of oral health with occurrence of head and neck cancer have been lacking particularly in longitudinal setting. We aimed to investigate the relationship between parameters of oral health and risk of head and neck cancer in a nationwide general population-based cohort.Methods : We included 150,774 subjects from the Korean National Health Insurance System-Health Screening Cohort for demographics, past history, and laboratory findings. The presence of periodontal disease and parameters of oral health including frequency of tooth brushings, dental visit for any reason, expertised dental cleaning, and number of tooth loss were investigated. Head and neck cancer was defined as International Statistical Classification of Diseases-10 codes of ‘C00-C14’.Results: During median 11.1 years of follow-up, 1,155 (0.76%) head and neck cancers occurred. Based on multivariable analysis, after adjusting for demographics, alcohol intake, smoking, regular exercise, body mass index, systolic blood pressure, blood and urinary laboratory findings, and parameters of oral health, frequent tooth brushing (more than three times per day) was related to lower risk of head and neck cancer (hazard ratio, HR: 0.78, 95% confidence interval, CI: 0.66–0.93, p=0.005). Increased number of tooth loss was positively associated with occurrence of head and neck cancer (p value for trend test for HR <0.001).Conclusions : The occurrence of head and neck cancer was decreased with the more frequent tooth brushing (more than three times per day) and increased with the number of tooth loss. In regards of head and neck cancer prevention, improving oral hygiene may have significant contribution.