Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 53 8 2024 08 06 1709 1721 Mohammad Alam 1. Department of Preventive Dentistry, College of Dentistry, Jouf University, Sakaka, Kingdom of Saudi Arabia 2. Department of Dental Research Cell, Saveetha Institute of Medical and Technical Sciences, Saveetha Dental College and Hospitals, Chennai, India 3. Department of Public Health, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh Haifa Almutairi College of Dentistry, Jouf University, Sakaka, Kingdom of Saudi Arabia Rowida Barayan Ministry of Health, Badanah Primary Healthcare, Badanah, Kingdom of Saudi Arabia Huda Abutayyem Department of Clinical Sciences, Center of Medical and Bio-Allied Health Sciences Research, College of Dentistry, Ajman University, Ajman, United Arab Emirates Haytham Alswairki School of Dental Sciences, Universiti Sains Malaysia, Kelantan, Malaysia Ahmed Alfawzan Department of Orthodontics and Pediatric Dentistry, College of Dentistry, Qassim University, Kingdom of Saudi Arabia Mohammad Hajeer Department of Orthodontics, University of Damascus Faculty of Dentistry, Damascus, Syria Ahmed Albalawi College of Dentistry, Jouf University, Sakaka, Kingdom of Saudi Arabia Khalid Hussain Ali Alruwaili Alruwaili College of Dentistry, Jouf University, Sakaka, Kingdom of Saudi Arabia Rakhi Issrani 1. Department of Preventive Dentistry, College of Dentistry, Jouf University, Sakaka, Kingdom of Saudi Arabia 2. Department of Research Analytics, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India Namdeo Prabhu Department of Oral & Maxillofacial Surgery and Diagnostic Sciences, College of Dentistry, Jouf University, Sakaka, Kingdom of Saudi Arabia 2023 05 08 2023 12 19 Background: We aimed to review studies that evaluated the effect of cigarette smoking on orthodontic treatment methods and determine whether the smoke affected appliances in a way that could impair the effectiveness of the overall treatment strategy. Methods: PubMed, Google Scholar, Cochrane Library, and Web of Science were scoured using pertinent keywords, reference searches, and citation searches in accordance with the PRISMA protocol regarding articles published from 2008 till 2022. Results: Ultimately, 7 papers were chosen for further analysis at the end of the selection protocol. Overall pooled odds ratio (OR) for the impact of cigarette smoking on orthodontic treatment was 0.25 (95% CI: 0.15, 0.43), with high statistical significance (P<0.00001) but also high heterogeneity (I² = 81%). The relative risk (RR) was 0.50 (95% CI: 0.38, 0.66), indicating a 50% greater risk of noticeable impact, with high statistical significance (P<0.00001) and high heterogeneity (I² = 79%), and the risk difference (RD), which was -0.33 (95% CI: -0.45, -0.21), suggesting a 33% higher risk of noticeable impact, with high statistical significance (P<0.00001) and high heterogeneity (I² = 81%). The high heterogeneity in all measures indicates significant variability in the results across the included studies. Conclusion: All the 7 studies selected for our systematic review exhibited significant detrimental associations between smoking and orthodontic appliances and other modalities that were exposed to cigarette smoke. However, more studies need to be done in this regard, since the literature currently available on this relationship is quite poor and lacking in concrete evidence. https://ijph.tums.ac.ir/index.php/ijph/article/view/31954 https://ijph.tums.ac.ir/index.php/ijph/article/download/31954/8306