LAUSR

Contemporary craniofacial surgery includes the preand post-operative optical 3D scanning of faces as a method for diagnosing and verifying the achieved results. The influence of head size in 3D scans must be excluded in order to accurately and uniformly compare different three-dimensional facial shapes in craniofacial surgery. Regarding this purpose, different head-size parameters must be measured to obtain the scaling factor. A special device, a so-called head ring, has been produced as a structure that can be fixed to a person’s head. Among defined points, different linear distances (head width, length and height) and volumetric parameters (lower and upper head volumes) were calculated and compared to body-size measurements. Measurements were performed on 3D scans of the heads of 26 healthy adults with normocclusion (12 men and 14 women) taken using the head ring set. Body mass index (BMI) statistically significantly correlates with the lower and whole-head volume in men, while in women more precisely with the upper-head volume. BMI in men does not correlate with any linear distance, while in women it is closely connected to the facial width. In men the head width and lower head volume are the main contributors to head size, while in women the crown-to-chin length and upper volume determine the size of the head. A conclusion can be made that the correlation between the head volume, the BMI and the linear head parameters exists and is gender dependent.