The facies are sometimes described as 'bird-like' with a beaked nose, brachycephaly, and micrognathia. Microstomia with a shortened ramus and forward displacement of the termporomandibular joints is characteristic. Upper airway obstruction may occur with severe respiratory distress. The forehead is relatively prominent, the palate is highly arched, and the teeth are often small and some may be missing with misalignment of others. A few teeth may even be present at birth (natal teeth). Children appear petite and are often short in stature. Scalp hair is thin, especially in the frontal and occipital areas, and the skin is atrophic. Developmental delays are common but most patients have normal or near-normal intelligence.