Malocclusion, Angle Class I

• Specialized Dental Center for Prosthodontics and Orthodontics — Baghdad, Bab Al-Muadham, Iraq
• Z Orchida Clinic — Baghdad, Iraq
• Orthodontic department, College of dentistry, university of Baghdad. — Baghdad, Iraq

• Outpatient Clinics of the Department of Orthodontics, Faculty of Dental Medicine, Boys, Cairo, Al-Azhar University. — Cairo, Cairo Governorate, Egypt

• Faculty of Dental Medicine (Boys), Al-Azhar University — Cairo, Cairo Governorate, Egypt

• Bezmialem Vakıf University — Istanbul, Fatih, Turkey (Türkiye)

• Faculty of Dentistry Cairo University — Cairo, Manial, Egypt

• The sample will be recruited from multicentre clinics (Private dental clinic, Orthodontic Department at Karbala Governmental Specialized Dental Centre, Orthodontic Department, College of Dentistry University of Baghdad). — Karbala, Iraq

• University of Geneva — Geneva, Canton of Geneva, Switzerland

Not specified

Not specified

• The University of Texas Health Science Center at Houston — Houston, Texas, United States