ABSTRACT
PURPOSE: This article describes construction of the average face and its application in the clinical environment. SUBJECTS AND METHODS: A total of 72 children, mean age 11.8 years, were selected for the study. Laser-scanned images of the subjects were obtained under a reproducible and controlled environment with 2 Minolta Vivid 900 (Minolta, Osaka, Japan) optical laser-scanning devices assembled as a stereo pair. A set of left and right scanned images was taken for each subject and each scan took an average of 2.5 seconds. These scanned images were processed and merged to form a composite 3-dimensional soft tissue reproduction of the subjects using commercially-available reverse modeling software. The differences in facial morphology were measured using shell deviation color maps. The average face was used to compare differences between male and female groups and 3 subjects with craniofacial anomalies. RESULTS: The difference between the average male and female face was 0.460 +/- 0.353 mm. The areas of greatest deviation were at the zygomatic area and lower jaw line, with the males being more prominent. The results of the surface deviation between the subjects with craniofacial anomalies were significant. CONCLUSIONS: The construction of the average face provides an interesting perspective into measuring changes in groups of patients and also acts as a useful template for the comparison of craniofacial anomalies.
Subject(s)
Cephalometry/standards , Craniofacial Abnormalities/pathology , Face/anatomy & histology , Imaging, Three-Dimensional/methods , Orthodontics/standards , Cephalometry/methods , Child , Facial Asymmetry/pathology , Female , Humans , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/instrumentation , Lasers , Male , Maxillofacial Development , Reference Standards , Reproducibility of Results , Sensitivity and Specificity , Sex FactorsABSTRACT
INTRODUCTION: The purpose of this prospective clinical trial was to evaluate the reliability of a 3-dimensional facial scanning technique for the measurement of facial morphology. METHODS: A field study was conducted in 2 comprehensive schools in the South Wales region of the United Kingdom. Forty subjects, mean age 11 years 3 months, were analyzed for soft tissue changes at baseline (T1), within 3 minutes (T2), and 3 days later (T3) by using 2 commercially available Minolta Vivid 900 (Osaka, Japan) laser-scanning devices assembled as a stereo pair. Left and right images were merged to form the whole face, and these images were superimposed to assess the errors at T1 and T2, and T1 and T3. RESULTS: The results showed that premerged left and right mean shell deviations were 0.38 +/- 0.14 mm for scans at T1, 0.31 +/- 0.09 mm at T2, and 0.34 +/- 0.12 mm at T3. The mean differences of the merged composite face were 0.31 +/- 0.08 mm between T1 and T2, and 0.40 +/- 0.11 mm between T1 and T3. Paired t tests showed no significant difference between these groups (P > .05). Shell deviation facial maps of the merged scans showed that 90% of the created composite facial scans were within an error of 0.85 mm. CONCLUSIONS: Capturing the soft tissue morphology of the face with this technique is clinically reproducible within 3 minutes and 3 days of the initial records.
