Mandibulofacial Dysostosis - Signs and Symptoms

Mandibulofacial Dysostosis - Signs and Symptoms

Mandibulofacial Dysostosis is characterized by a wide variety of clinical features depending on the branchial arches involved in the developmental malformation. The first thing that is apparent on looking at a person affected by the condition is the presence of anti-mongoloid palpebral fissures and the partially absent eyelids. Sometimes the eyelashes are completely absent. There is a deficient growth in facial bones especially that of the mandible or the lower jaw and the malar bones, also called the cheek bones. This results in a narrow facial structure giving the patient a characteristic appearance referred to as the Parrot Beak appearance. The external ear, the middle ear and the internal ear are deformed to some extent. In some situations, these structures are completely absent. Cleft palate can also occur if the palatal shelves have not fused Cleft lip is also a common feature. A patient of Mandibulofacial Dysostosis has a high palatal arch-giving rise to speech difficulties. The teeth are abnormally positioned and do not always relate to those in the opposing arch/bone resulting in malocclusion. Another striking feature of the disease is the presence of blind fistulas* between the angle of the mouth and the ears. There is unusual growth of hair converging towards the cheeks. This gives a fish like appearance to the face.

It is theorized that Mandibulofacial Dysostosis occurs due to the failure of the maxillary mesoderm to develop beyond what is called the 50 mm stage of the embryo. This means that the trigger that spurs the development of the head and neck region is either faulty or completely absent. This theory is supported by evidence of teeth formation by the sixth week of fetal life. The teeth in the upper jaw are especially affected in this condition and are place in quite unusual positions. Sometimes they fail to erupt and are embedded in the bone itself. Patients with Mandibulofacial Dysostosis are prone to fracture quite easily because of the fragile nature of facial bones. Even a push could bruise the face quite easily. Because of the malformation of the ears, patients can also suffer from hearing loss.

A syndrome called as the Goldenhar syndrome has similar features as the Mandibulofacial Dysostosis. It is also called as hemifacial microsomia, but occurs less frequently than MD. In Goldenhar syndrome, the defects are unilateral in distribution as against the bilateral features in MD and is postulated to occur due to the interruption in blood supply to the face.