ABSTRACT Obstructive sleep apnea is the most common sleep related breathing disorder that is characterized by recurrent episodes of complete or partial obstruction of airway leading to reduced or absent breathing during sleep. Most common trigger factors are obesity, anatomical defects in the pharynx and reduction in airway which disrupts routine sleep cycle and results in reduced quality of life. This review article describes the sequalae of events due to OSA and importance in the diagnosis and management of OSA by orthodontists.