Oral manifestations in young adults infected with COVID-19 and impact of smoking: a multi-country cross-sectional study oleh Maha El Tantawi, Heba Jafar Sabbagh, Nada Abubakor Alkhateeb, Maryam Quritum, Joud Abourdan, Nafeesa Qureshi, Shabnum Qureshi, Ahmed Hamoud, Nada Mahmoud, Ruba Odeh, Nuraldeen Maher Al-Khanati, Rawiah Jaber, Abdulrahman Loaie Balkhoyor, Mohammed Shabi, Morenike O. Folayan, Noha Gomaa, Raqiya Al_Nahdi, Nawal Mahmoud, Hanane El Wazziki, Manal Alnaas, Bahia Samodien, Rawa Mahmoud, Nour Abu Assab, Sherin Saad, Sondos Al-Hachim, Ali Alshaikh, Wafaa Abdelaziz