The estimated point orbitale results from the facebow’s nasion relator height of 25.4 mm.
We used lateral cephalometric radiographs of 420 individuals (210 males, 210 females,) and divided the sample into 7 age groups.
A single investigator measured the perpendicular distance of soft tissue nasion to a line connecting the averaged arbitrary hinge axis point and the averaged point orbitale.
There were no significant differences of the distance between age groups, or sex within age groups, or sex between age groups.
The present study’s data did not preclude application of this nasion relator height from age 6 years onward.
Anatomical facebows establish the arbitrary axis-orbital plane by assessing both the hinge axis points and landmark orbitale. The estimated point orbitale results from the facebow’s nasion relator height of 25.4 mm. This height was investigated in adults but it is unclear if their anthropometric dimensions adequately translate to children and adolescents. The present cross-sectional study aimed to evaluate the validity of this height retrospectively for the ages 6 to19.9 years. We used lateral cephalometric radiographs of 420 individuals (210 males, 210 females,) and divided the sample into 7 age groups. A single investigator measured the perpendicular distance of soft tissue nasion to a line connecting the averaged arbitrary hinge axis point and the averaged point orbitale. Data were analyzed using an ordinary least squares linear regression model (p < 0.05). The perpendicular distances ranged from 11 to 33.5 mm (mean 22.8, standard deviation 3.5). There were no significant differences of the distance between age groups, or sex within age groups, or sex between age groups. The use of a fixed 25.4 mm nasion relator height in children and adolescents was not associated with more instrumental error in assessing point orbitale than in the adult age group. The present study’s data did not preclude application of this nasion relator height from age 6 years onward.
