Assessing cervical spine and craniofacial morphology in Class II and Class III malocclusions: A geometric morphometric approach

ABSTRACT

To compare craniofacial and cervical morphology between skeletal Classes II and III applying Geometric Morphometric Methods (GMM). Twenty-six cervical and craniofacial landmarks of 40 Class II and 39 Class III individuals were digitalized on lateral cephalograms. Procrustes ANOVA, generalized Procrustes, principal component analyses, and thin-plate spline function were applied to assess the pattern of shape variation of craniofacial structure and the cervical spine in relation to skeletal classes. Compared with Class III, Class II individuals presented a maxillary protrusion, mandibular retrusion, shorter mandibular corpus, posterior mandibular ramus rotation, anterior cranial base rotation, and a smaller centroid size. Furthermore, a forward and smaller cervical spine were observed. With GMM, the shape and size differences between skeletal classes can be analyzed visually and numerically.

KEYWORDS:

• Malocclusion
• skeletal class
• geometric morphometrics
• cervical vertebrae
• craniofacial morphology

Acknowledgments

We thank Mr. Juan Fernández de los Ríos, from the Language and Translation services, Direction of Academic Affairs, Faculty of Dentistry, Universidad de Chile, and Ms. Claudia Trajtemberg, MPhil University of Cambridge, UK, for kindly proofreading the manuscript to improve its grammar and syntax. We also thank Ms. Claudia Salgado Camacho, visual artist, Universidad de Chile, for editing and improving the figures of the present work.

Contributors

The authors declare that no other contributor took part of this work.

Disclosure statement

There was no conflict of interest.

Supplemental Material

Supplemental data for this article can be accessed on the publisher’s website

Additional information

Funding

CThis work was supported by Programa de Investigación Asociativa. Anillo de Investigación en Ciencia y Tecnología under Grant ACT-96 (http://repositorio.conicyt.cl/handle/10533/207268).