Maha Abdul- Kareem Mahmood1Esra Hassan Abd Ali1 ,. 2019. “The Effect of Fixed Space Maintainer Appliances on Salivary Level of Immunoglobulin A and Other Saliva Properties”. Iraqi Journal of Biotechnology 14 (1). https://jige.uobaghdad.edu.iq/index.php/IJB/article/view/240.