Abstract: Abstract：　Objective　Comparative study of three-dimensional of the upper airway in patients with non-syndromic cleft lip and palate Methods　51 patients with non-syndromic cleft lip and palate were selected (37 males, 14 females, mean age 17.4±5.93 years) and 53 patients with skeletal class I population from department of Orthodontics(39 males and 14 females, mean age 17.4±6.07 years). The cone beam CT was taken, and the three-dimensional measurement analysis was performed using Dolphin 3D 11.9 software. The SPSS 25.0 software package was used for statistical analysis to compare the volume and minimum area of the upper airway. Results　The upper airway volume of the nasopharyngeal segment of patients with non-syndromic cleft lip and palate was larger than that of skeletal class I population(P<0.01), but there was no significant difference between the rest of the airway and the total volume (P>0.05); The minimum area of the nasopharyngeal and pharyngeal segments of patients with non-syndromic cleft lip and palate was greater than that of skeletal class I population(P<0.05). Conclusions　The upper airway three-dimensional structure of patients with non-syndromic cleft lip and palate may be similar to the skeletal class I population,the upper airway respiratory function in patients with non-syndromic cleft lip and palate may be affected by multifunctional factor.

Key words: non-syndromic cleft lip, CBCT, upper airway