Assessment of the Airway Characteristics in Children

lip and palate (CLP)1 compared with those in normal subjects; patients with CLP have a smaller upper airway compared with normal controls.2,3 Parents of children with CLP have often reported that their children snore and breathe noisily during sleep, and patients with reduced nasal airways are also predisposed to mouth breathing.4-6 Rose et al7 found that patients with cleft palate had significantly elevated incidences of mouth breathing, snoring and hypopnea during sleep. These clinical findings are considered to represent the initial symptoms of sleep-disordered breathing. The high risk for sleep-disordered breathing in children with CLP is caused by the dysfunction of muscles controlling the soft palate in conjunction with structural abnormalities of the maxilla and the mandible.2 Patients suffering from sleep-disordered breathing are at increased risk for hypertension, cardiovascular and cerebrovascular diseases and excessive daytime sleepiness.8 Morphometric evaluation of the pharyngeal airway is, therefore, important in patients with CLP. Most previous evaluations have been performed by identifying landmarks on lateral cephalometric images and measuring standard lengths and areas in the pharyngeal region.3,9,10 Lateral cephalograms are limited by the inherent errors accompanying the two-dimensional (2D) representation of a three-dimensional (3D) structure, including distortion, differences in magnification and the superposition of the bilateral craniofacial structures.11 With the advent of low-radiation, rapid computed tomography (CT) scanning,12-16 the potential for orthodontists to assess craniofacial growth in 3D is now available,17,18 and with that analysis is the capability of evaluating the complete airway.19,20 The aim of this study is to assess nasopharyngeal, aerial and adenoidal soft-tissue characteristics in patients with CLP and to compare the results with patients with ideal occlusion.