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,
Jaw abnormality by the ‘scleral show and eyelid shape.’ The lower eyelid normally rests at the inferior border of the iris, without any sclera showing. If there is any sclera showing, then this is a good sign of infraorbital rim deficiency and maxillary antero-posterior deficiency, two manifestations that are usually seen in Class III patients. When a jaw is "abnormally oriented," malrotations occur. These "malrotations" are classified according to the axis on which the abnormal rotation occurs. When a jaw is malrotated around the transverse facial axis, it is said to have "abnormal pitch". When malrotated around the anteroposterior axis, the jaw