J Korean Assoc Maxillofac Plast Reconstr Surg.  2012 Jan;34(1):17-25.

Manikin Model Study on Reproducibility and Accuracy of Maxillofacial Measurements Determined by Stereocamera: Comparative Study of Direct Anthropometry, Digitizer and Stereophotogrammetery

• Jeoung YW
• Yang JW
• Chung K
• Kook MS
• Oh HK

Abstract

PURPOSE
Recently, a three dimensional approach to hard and soft tissues of the maxillofacial area has been widely used. This study was to evaluate the reproducibility and accuracy of a stereocamera compared to actual measurement methods using a digital caliper and digitizer.
METHODS
The stereoscopies of 7 head dummies with different sizes and shapes were obtained using a Di3D system (Dimensional Imaging, Glasgow, UK) after marking reference points on facial areas. From the obtained stereoscopy, 10 measurements representing the width, height and depth of each of the facial sections of the dummy were measured twice using a three dimensional reverse engineering software program (RapidForm(TM) 2006, Inus, Seoul, Korea). The x, y, and z coordinates of each of the three dimensional measurements were obtained and distances between two points were calculated. All procedures were repeated twice. The actual measurement method was performed twice, directly on dummies, using a digital caliper and values were compared with the previously determined values.
RESULTS
The results were as follows. In the ANOVA analysis, there were no significant statistical differences among the three measurement methods. In the Bonferroni analysis, with adjustments applied for multiple comparisons, there was no difference between actual measurement methods using a digitizer and a digital caliper. However, there was some difference between using a stereocamera and actual measurement methods using a digitizer and a digital caliper in values of ExRt-ExLt, EnRt-EnLt, AlaRt-AlaLt, ChRt-ChLt, G-Pg', AlaRt-Prn, AlaRt-Prn. The mean value for technical error in measurement (TEM) in Di3D (0.98 mm) was slightly higher than for a digital caliper (0.17 mm) and a digitizer (0.30 mm). In an intraclass correlation coefficient (ICC) there were no significant differences among the three measurement methods, but the Di3D system with the stereocamera showed relatively lower reproducibility compared to actual measurement methods using a digitizer and a digital caliper.
CONCLUSION
These results indicate that some complementary measures may be needed to improve accuracy and reproducibility in the Di3D system with stereocamera.

Keyword

Stereocamera; Anthropometry; Digitizer; Accuracy; Reproducibility

MeSH Terms

Anthropometry
Head
Manikins