Studies in knockout of Nog shows abnormalities in the neural tube and the somites and mandibular defects ranging over a range of phenotypes from the mandibular hypoplasia
, passing through an intermediate phenotype micrognathia (poor formation of the jaw) to agnathia (absence of mandibular formation) (88,89).
Otocephaly is a rare often lethal, non familial syndrome characterized by severe mandibular hypoplasia
, synotia, microstomia and severe hypoplasia of tongue (1).
Further features include other rib anomalies, deficiency of the lateral clavicle, mandibular hypoplasia
, macrocephaly and mental retardation.
* In utero exposure to isotretinoin (13-cisretinoic acid), an analog of vitamin A used to treat cystic acne, is associated with a characteristic pattern of malformations, including abnormal ear development, a flat nasal bridge, mandibular hypoplasia
, cleft palate, hydrocephalus, neural tube defects, and conotruncal heart defects (Lammer et al.
The classical features of Goldenhar syndrome patients involve ocular anomalies, including microphthalmia, anophthalmia, epibulbar dermoid (or lipodermoid) tumors, and eyelid colobomas, aural defects, such as preauricular tags, anotia, microtia, and hearing loss, vertebral abnormalities, such as scoliosis, hemivertebrae, and cervical fusion, and mandibular hypoplasia
This early fusion preventing skull growth also shows facial dysmorphism including a long narrow head, Hypertelorism, bilateral Exophthalmos, antimongoloid slant of a palpebral fissure, a high arched palate, severe mandibular hypoplasia
and narrow maxilla, low set ears.
Distraction osteogenesis is an alternative treatment method for the correction of mandibular hypoplasia
. In this study, distraction with a unidirectional extra oral device was performed to gradually lengthen the corpus and ramus of patients who had hypo-plastic mandible.
The patient had severe mandibular hypoplasia
and clefting of the hard palate, and he was diagnosed with syndromic Pierre Robin sequence (figure 2, A).