S. Qasim, Ashraf, Omar S Rahawi, and Ammer A Sultan. 2009. “The Effect of in-Office Tooth Whitening on the Microhardness of Esthetic Restoration (An Invitro Study)”. Al-Rafidain Dental Journal 9 (1):83-89. https://doi.org/10.33899/rden.2009.9002.