Geometric Morphometric Methods for Bone Reconstruction: The Mandibular Condylar Process of Pico della Mirandola

Abstract

The issue of reconstructing lost or deformed bone presents an equal challenge in the fields of paleoanthropology, bioarchaeology, forensics, and medicine. Particularly, within the disciplines of orthodontics and surgery, the main goal of reconstruction is to restore or create ex novo the proper form and function. The reconstruction of the mandibular condyle requires restoration of articulation, occlusion, and mastication from the functional side as well as the correct shape of the mandible from the esthetic point of view. Meeting all these demands is still problematic for surgeons. It is unfortunate that the collaboration between anthropologists and medical professionals is still limited. Nowadays, geometric morphometric methods (GMM) are routinely applied in shape analysis and increasingly in the reconstruction of missing data in skeletal material in paleoanthropology. Together with methods for three-dimensional (3D) digital model construction and reverse engineering, these methods could prove to be useful in surgical fields for virtual planning of operations and the production of customized biocompatible scaffolds. In this contribution, we have reconstructed the missing left condylar process of the mandible belonging to a famous Italian humanist of the 15th century, Pico della Mirandola (1463-1494) by means of 3D digital models and GMM, having first compared two methods (a simple reflection of the opposite side and the mathematical-statistical GMM approach) in a complete human mandible on which loss of the left condyle was virtually simulated. Finally, stereolithographic models of Pico's skull were prototyped providing the physical assembly of the bony skull structures with a high fitting accuracy. Anat Rec, 292:1088Rec, 292: -1097Rec, 292: , 2009. V V C 2009 Wiley-Liss, Inc.Key words: virtual anthropology; condylar process; geometric morphometrics; stereolithographyThe problem of reconstruction of fractured, distorted, or missing parts in human skeleton has been given considerable attention in the fields of archaeology, forensic anthropology, and paleoanthropology. As a result, a large amount of knowledge has been amassed to date, including the recent development of the noninvasive computerized methods of virtual reconstruction (Ponce De León

Virtual Reconstruction of Very Large Skull Defects Featuring Partly and Completely Missing Midsagittal Planes

“…Computer‐based methods have been extensively used in the last years to overcome the limits of manual cranial reconstructions (Ponce De León and Zollikofer, ; Neubauer et al, ; Zollikofer and Ponce De León, ; Benazzi et al, ,,; Grine et al, ; Benazzi et al, ,b; Weber and Bookstein, ; Benazzi et al, ). Nonetheless, even though digital methods allow to reproduce missing parts and increase the reproducibility of the results, our study is the first one documenting the quantification of the accuracy for restoring very large missing portions of a human cranium.…”

“…Furthermore, cranial reconstruction is a fundamental issue for surgical disciplines, including orthodontics and maxillofacial surgery, to restore both form (for aesthetic purposes) and function (articulation, occlusion, and mastication) (i.e., Mehta and Deschler, ; Young et al, ; Baumann et al, ). In the last decade computer‐based methods for digital reconstruction of skeletal features have emerged and are now used in bioarchaeology and forensic anthropology (Fantini et al, ; Benazzi et al, , ), paleoanthropology (Ponce De León and Zollikofer, ; Neubauer et al, ; Gunz, ; Zollikofer and Ponce De León, ; Gunz et al, ; Grine et al, ; Benazzi et al, ; Weber and Bookstein, ; Benazzi et al, ), and recently emphasis has been given to its potential applications in craniomaxillofacial surgery (i.e., Benazzi and Senck, ; Benazzi et al, ). Digital reconstruction techniques include a full documentation of the process, which leads to reproducible results and less error‐prone to subjectivity compared to traditional manual approaches.…”

Virtual anthropology and forensic arts: the facial reconstruction of Ferrante Gonzaga

“…The left condyle of the mandible was reconstructed using thin plate spline (TPS) interpolation functions following the procedures outlined by Benazzi et al (2009c). A template made by three anatomical landmarks and 121 semilandmarks was created on the mirrored copy of the right hemimandible (reference model) in Viewbox software (dHAL Software, Kifissia, Greece).…”

Geometrical Models of Mandible Fracture and Plate Implant

“…The mandible (lower jaw) is the largest and the strongest bone in the face and its shape is very complex [7,8]. Mandible fractures are common facial injuries treated by the oral and maxillofacial surgeons as described in [1,2].…”