X: {HEAD ~ axial distance} from {TAIL ~ the origin} at the tooth surface at the center of the tooth thickness, 
from
X : { HEAD ~ axial distance } from { TAIL ~ the origin } at the tooth surface at the center of the tooth thickness ,
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH