Jaw abnormality sagittally divides the face into five equal parts: It is insufficient to derive at a diagnosis of jaw deformity solely based on the clinical examination. Hence, additional information is gathered from diagnostic tests, which may include dental model analyses and radiographic imaging studies. Mandibular micrognathia is the condition when lower jaw is smaller than normal. Failure of the ramus to develop will give rise to micrognathia.<ref name="Elsevier/Churchill Livingstone"></ref> Micrognathia can be classified as either congenital or acquired. Clinical appearance of some patients with congenital type of mandibular micrognathia can have a severe retrusion of the chin but by actual measurements,
Radium jaw Radium jaw Radium jaw is an occupational disease brought on by the ingestion and subsequent absorption of radium into the bones of radium dial painters and those consuming radium-laden patent medicines. The symptoms are necrosis of the mandible (lower jawbone) and the maxilla (upper jaw), constant bleeding of the gums, and (usually) after some time, severe distortion due to bone tumors and porosity of the lower jaw. The condition is similar to phossy jaw, an osteoporotic and osteonecrotic illness of matchgirls, brought on by phosphorus ingestion and absorption. The first written reference to the disease was by a dentist, Dr.