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,
Phossy jaw ... spreading to neighboring teeth and jawbone". Over time, pus formation developed penetrating the oral mucosa with the formation of fistula, teeth loss, and recurrent abscesses. Further progression led to the formation of sequestrum (dead bone that has separated from living bone) after 3 months and necrosis of the jaw within 6 months. The distinguishing feature of this disease was the eventual separation of the sequestrum which was described as porous and light in weight. The lower jaw was more commonly affected than the upper jaw. Affected bones glowed a greenish-white colour in the dark. The condition also caused serious