Taheri, S. et al. 2024. Association between Passive Smoking, Salivary Calcium level, and Periodontal Health: A Cross-Sectional Study : Passive Smoking and Periodontal Health. Regeneration, Reconstruction & Restoration (Triple R). 9, (Sep. 2024). DOI:https://doi.org/10.22037/rrr.v9.45535.