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. 2017 Dec 1;18(1):38.
doi: 10.1186/s40510-017-0194-9.

Measuring 3D shape in orthodontics through geometric morphometrics

Luis Huanca Ghislanzoni  1   2 , Roberta Lione  3 , Paola Cozza  3 , Lorenzo Franchi  4
Affiliations

Measuring 3D shape in orthodontics through geometric morphometrics

Luis Huanca Ghislanzoni et al. Prog Orthod. .

Abstract

Background: Geometric morphometrics (GMM) has been traditionally applied to the field of biology to study developmental differentiations between species. Orthodontics deals with the shape and size of the face and its components. While several tools have been used to measure size, proportions, and relations between anatomical components, shape has been mainly described by esthetic criteria. The purpose of this paper is to present methods to measure shape of 3D orthodontic data, beyond the conventional tools that have been traditionally used in cephalometrics and in facial and dental cast analysis.

Findings: The authors showcase an example of applying geometric morphometrics to measure palates from scanned dental casts. GMM can be used as a useful tool to describe the three-dimensional shape of surfaces of orthodontic interest. A general introduction to the theoretical principles of how to apply GMM is provided.

Conclusions: Variability can be measured through the Principal Component Analysis (PCA) and can lead to the identification of shape patterns and sources of variability of the shape, independently from changes in size.

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Conflict of interest statement

Ethics approval and consent to participate

Ethical approval was obtained from the Ethical Committee of the University of Rome “Tor Vergata” and informed consent was obtained from the subjects’ parents before inclusion in the study.

Competing interests

The authors declare that they have no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Figures

Fig. 1
Fig. 1
The template of 240 landmarks and semi-landmarks used to study the palatal shape
Fig. 2
Fig. 2
Clusterized results: in green, nose breather/controls; in red, mouth breathers/patients. On the x-axis PC1, on the y-axis PC2 from Principal Component Analysis calculation
Fig. 3
Fig. 3
On the left, PC1 resulted into 50% of variability source: the main difference consisted of a larger and shorter palatal vault height vs a narrower and higher palate. Blue lines show the trend of mouth breathers; red lines show the trend of nasal breathers
Fig. 4
Fig. 4
Colorimetric maps showing the differences in shape after superimposition between the average palate of mouth breathers and nasal breathers: the palate is narrower and higher in mouth breathers
See this image and copyright information in PMC

References

    1. Klingenberg CP, Wetherill L, Rogers J, et al. Prenatal alcohol exposure alters the patterns of facial asymmetry. Alcohol. 2010;44(7–8):649–657. doi: 10.1016/j.alcohol.2009.10.016. - DOI - PMC - PubMed
    1. Polychronis G, Christou P, Mavragani M, Halazonetis DJ. Geometric morphometric 3D shape analysis and covariation of human mandibular and maxillary first molars. Am J Phys Anthropol. 2013;152(2):186–196. - PubMed
    1. Bookstein FL. Morphometric tools for landmark data: geometry and biology. New York: Cambridge Univ. Press; 1991.
    1. Weber GW, Bookstein FL. Virtual anthropology: a guide to a new interdisciplinary field. New York: Springer; 2011.
    1. Webster M, Sheets D. A practical introduction to landmark-based geometric morphometrics. Paleontol Soc Pap. 2010;16:163–188.