Sleep Disordered Breathing in Children with Achondroplasia. Part 2. Relationship with Craniofacial and Airway Morphology

We evaluated the craniofacial and airway morphology in children with achondroplasia complicated by snoring and apnea during sleep (AP group) in comparison with children with snoring and apnea during sleep without chromosomal aberrations (adenoid group) and healthy children without sleep disordered breathing or malalignment (healthy group). Lateral cephalograms in 10 children each (four males and six females) in the three groups were analyzed. When the AP and healthy groups were compared, the AP group showed significantly lower values for facial depth, nasal floor length, point A, point pog, and saddle angle (p<0.01) and significantly higher values for mandibular plane angle and gonial angle (p<0.01) regarding craniofacial morphology and significantly lower values for D-AD1, D-AD2, and upper pharynx (p<0.01) regarding airway morphology. When the AP and adenoid groups were compared, the AP group showed significantly lower values for facial depth, nasal floor length, point A, point pog, and saddle angle (p<0.01) and significantly higher values for mandibular plane angle and gonial angle (p<0.01) regarding craniofacial morphology and significantly lower values for D-AD1, D-AD2, and upper pharynx (p<0.05) regarding airway morphology. Thus, the craniofacial/airway morphology in the AP group was characterized by upper airway stenosis, a retruded position of the chin, and an increased mandibular plane angle due to partial early ossification of cranial bones, and an increased lower facial height due to an increased mandibular angle, which may tend to induce sleep snoring and apnea.