Objective: The aim of this study was to investigate the effect of cigarette smoking on the failure rates of orthodontic miniscrews.
Patients and methods: Our cohort consisted of 88 patients with a total of 110 orthodontic miniscrews. Based on their smoking habits, the patients were divided into three groups: the light smokers (< or = 10 cigarettes/day), heavy smokers (> 10 cigarettes/ day), and non-smokers. The light-smoker group consisted of 14 patients with 18 orthodontic miniscrews, and there were 15 patients with 19 miniscrews among the heavy smokers. The nonsmoker group contained 59 patients with a total of 73 miniscrews.
Results: The overall failure rate was 18.2% (n = 20). Heavy smokers revealed a significantly higher failure rate than light smokers (p = 0.005) or non-smokers (p < 0.001). No significant differences were observed between non-smokers and light smokers. Miniscrews in the heavy smoker group exhibited a significantly higher failure rate during the first 4 months after insertion than did the miniscrews in the light smokers (p = 0.008) or non-smokers (p < 0.001).
Conclusion: Our results suggest that heavy smoking has a detrimental effect on the success rates of orthodontic miniscrews.