Aim: The objective of this study was to establish the characteristics of the nasopharyngeal airway in adult cleft lip/palate subjects (CLP), and to compare them with normal adult subjects using three-dimensionally cone beam computed tomography images (3D CBCT).
Subjects and Methods : The sample comprised control subjects (n=15) and adult unilateral cleft lip/palate subjects (n=15). Eighty-seven scans derived from 3D CBCT of the two groups were analyzed.  A set of airway, and group of volumetric parameters were measured. CBCT scans were coded and measurements Landmarks were identified and measured using Dolphin 3D Imaging software server (version 11.7; Patterson Dental Supply, Chatsworth,Calf.).
Results: All the volumetric measurements of the cleft group showed significant lower total volume for Nasal Cavity, Nasopharynx ,Oropharynx ,Hypopharynx and total airway volume than the control group.
Conclusion: Adult unilateral CLP subjects had smaller nasopharyngeal parameters relative to normal adult subjects.