en.wikipedia.org/wiki/Prognathism
1 correction found
Prognathism is a positional relationship of the mandible or maxilla to the skeletal base where either of the jaws protrudes beyond a predetermined imaginary line in the coronal plane of the skull.
This definition uses the wrong anatomical plane. Prognathism is assessed from the side/profile in the sagittal plane, not the coronal plane.
Full reasoning
The article’s definition is anatomically incorrect because it places prognathism in the coronal plane. The coronal plane divides the body into front and back portions; it is not the side-profile plane used to judge jaw projection.
Authoritative morphology terminology from NHGRI defines prognathism as “anterior protrusion ... best appreciated in profile” and describes it relative to the vertical plane of the maxillary alveolar ridge. CARTA likewise states that prognathism is usually measured with the craniofacial angle formed in the sagittal plane. MedlinePlus also defines prognathism simply as protrusion of the lower jaw, consistent with a forward/profile abnormality rather than a coronal-plane one.
So the problem is not the general idea that the jaw projects forward; it is specifically the statement that this is judged in the coronal plane of the skull, which is the wrong plane.
3 sources
- Human Malformation Terminology (NHGRI): Prognathism
Definition: Prognathism. Subjective: Anterior protrusion of the mandibular alveolar ridge beyond the vertical plane of the maxillary alveolar ridge, best appreciated in profile.
- CARTA: Prognathism
Prognathism is usually measured with the craniofacial angle ... formed in the sagittal plane...
- MedlinePlus Medical Encyclopedia: Prognathism
Prognathism is an extension or bulging out (protrusion) of the lower jaw (mandible).