Posterior Crossbite

• Cairo University — Cairo, Egypt

• Department of Orthodontics, Faculty of Dental Medicine, Al-Azhar University — Cairo, Naser City, Egypt

• Faculty of Dental medicine (boys) ,Cairo,Al-Azhar University — Cairo, Cairo Governorate, Egypt

• Faculty of Dentistry, Alexandria University — Alexandria, Egypt

• Faculty of Dentistry, Alexandria University — Alexandria, Egypt

Not specified

• Pontifícia Universidade Católica de Minas Gerais — Belo Horizonte, Minas Gerais, Brazil

• Department of Orthodontics, University of Damascus Dental School — Damascus, Syria

• Ortohdontic Department - Univesity of Genoa — Genova, Italy
• Ortohdontic Department - Univesity of Siena — Siena, Italy
• Orthodontic Department - University of Varese — Varese, Italy