Mahmood, Y.G. , Hussein, V.M. and Aziz, A.H. 2023. The relationship between serum vitamin D level & chronic periodontitis in patients attending Khanzad center in Erbil city. AMJ (Advanced Medical Journal) . 5, 2 (Jun. 2023), 99-104. DOI:https://doi.org/10.56056/amj.2019.109.