Measured using frankfurt horizontal line and mandibular angle (line on lower border of mandible) - average is 27 degrees. The position of where both lines meet will determine the vertical relationship. In front occiput = increased VD. On occiput = average VD. Behind occiput = decreased VD. What is the measurement method for determining the vertical relationship using the frankfurt horizontal line and mandibular angle?
1) Frankfurt horizontal line
2) Mandibular angle
3) Measurement of VD
4) Measurement of occiput