[1] Thamar Univ, Dept Prosthodont, Fac Dent, Dhamar, Yemen
[2] Jordan Univ Sci & Technol, Dept Community Med Publ Hlth & Family Med, Fac Med, Irbid, Jordan
[3] Al Qadisiyah Univ, Dept Oral Diag, Coll Dent, Al Diwaniya, Iraq
[4] Univ Zagreb, Dept Removable Prosthodont, Fac Dent, Zagreb, Croatia
[5] Jazan Univ, Div Oral Med, Dept Maxillofacial Surg & Diagnost Sci, Coll Dent, Jazan, Saudi Arabia
[6] Univ San Martin de Porres, Dept Oral Rehabil, Fac Dent, Lima, Peru
[7] Univ Western Cape, Dept Restorat Dent, Fac Dent, Cape Town, South Africa
[8] BP Koirala Inst Hlth Sci, Dept Prosthodont & Crown Bridge, Coll Dent Surg, Dharan, Nepal
[9] St Joseph Univ Beirut, Dept Removable Prosthodont, Fac Dent, Beirut, Lebanon
[10] Univ Sao Paulo, Sch Dent Ribeirao Preto, Dept Restorat Dent, Sao Paulo, Brazil
[11] Nitte Univ, AB Shetty Mem Inst Dent Sci, Dept Prosthodont & Crown Bridge, Mangalore, India
[12] Univ Lahore, Dept Prosthodont, Univ Coll Med & Dent, Punjab, Pakistan
[13] Private Dent Clin, Punjab, Pakistan
[14] Pharos Univ Alexandria, Fac Dent, Dept Implants & Removable Prosthodont, Alexandria, Egypt
[15] Univ Khartoum, Dept Basic Sci, Fac Dent, Khartoum, Sudan
[16] Al Gazira Univ, Dept Prosthodont, Fac Dent, Wad Madani, Sudan
[17] Thamar Univ, Conservat Dept, Fac Dent, Dhamar, Yemen
[18] Private Dent Clin, Dhamar, Yemen