Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 20 0 2023 05 02 1 7 Adileh Shirmohammadi Department of Periodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran Sanaz Mohammadi Department of Periodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran Masoumeh Faramarzi Department of Periodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran Amir Babaloo Department of Periodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran Mehrnoosh Sadighi Department of Periodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran Solmaz Maleki Dizaj Dental and Periodontal Research Center, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran. 2020 12 30 2021 08 31 Objectives: Vitamin D deficiency appears to have a major effect on periodontal tissue health. The present study aimed to assess the association of the serum level of 25-hydroxyvitamin D and chronic periodontitis in postmenopausal women. Materials and Methods: This research was done on 30 postmenopausal women with chronic periodontitis who all had at least 20 natural teeth. Intravenous blood samples were taken from the study population at baseline and after completion of non-surgical periodontal treatment. This was followed by assessment of serum levels of 25-hydroxyvitamin D. Next, clinical parameters of all teeth except for third molars were measured, which included pocket depth (PD), gingival index (GI), and plaque index (PI). Data were analyzed by paired t-test and its non-parametric equivalent, the Wilcoxon test. P<0.05 was considered significant. Results: The mean PD, PI and GI before and after the intervention were significantly different (P<0.05). There was, however, no significant difference between the mean vitamin D concentrations before and after treatment (P>0.05). Conclusion: According to the results obtained in the present study, there is no association between serum vitamin D concentrations and chronic periodontitis in postmenopausal women. https://fid.tums.ac.ir/index.php/fid/article/view/3905