a. Prognathism properly so-called: prominence of the upper maxilla as a whole.
b. Prophatnia.—Prominence of the alveoli.
c. Progeneism.—Prominence of the mandible—the lower dental arch projects in front of the upper.
Measurements of the Thorax
Principal anthropometric points: acromial point; sternal fossa; xiphoid point; mammillary points.
Measurements.—Thoracic Circumference.—Already described among the measurements of the form.
Recording instruments are now made that are exceedingly complicated and quite costly, that register the movements of respiration; they are used in medical clinics, but would be of little practical use in our schools.
Axillary and Submammary Circumference.—Taken as above, but at different levels.
Biacromial Diameter.—This is taken by means of special calipers called a thoracimeter or pelvimeter, because it is used to obtain the big measurements of the body (thorax and pelvis). The two buttons at the ends of the branches are applied to the acromial points, while the measurer occupies a position in front of the subject to be measured.