Causal Effect of Smoking and Cessation on Tooth Loss

Aim: To estimate the causal effects of smoking and cessation on tooth loss using instrumental variable (IV) analysis.

Material and methods: Data from the Behavioural Risk Factor Surveillance System (BRFSS), conducted from 1995 to 2006, 2008, 2010, and 2012 in 50 U.S. states and Washington DC, were merged with cigarette pack prices and smoking ban data from the CDC 'Tax Burden on Tobacco' and 'State Tobacco Activities Tracking and Evaluation' (STATE) System. Prices and bans served as IVs for ever smoking and cessation in a control function IV model for self-reported edentulism and loss of 6+ teeth. IV models were adjusted for age, sex, race/ethnicity, educational attainment, type 2 diabetes, state unemployment rates, state health expenditures, and state fixed effects.

Results: Ever smoking cigarettes increased the risk of edentulism by 2.6% (95% CI: 2.3%-2.8%) and the risk of loss of 6+ teeth by 10.7% (95% CI: 10.0%-11.3%). Smoking cessation reduced risks of edentulism and loss of 6+ teeth by 7.6% (95% CI: -7.8% to -742%) and 13.5% (95% CI: -13.7% to 13.3%), respectively.

Conclusion: This study provides robust evidence that smoking increases tooth loss risk, while cessation significantly reduces it, emphasizing the oral health benefits of tobacco control policies.