Reliability of measuring facial morphology with a 3-dimensional laser scanning system

ntroduction: 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