Practical Application of Anatomy of the Oral Cavity in Forensic Facial Reconstruction

Abstract

The oral cavity’s importance in defining the facial region makes it a primary feature for forensic facial reconstruction (FFR). The aim of this study is to construct a pattern of reference for dimensions and proportions of the lips and establish parameters that may help estimate the vermilion borders’ height dimensions and the mouth’s width. By means of cone beam computed tomography, divided into two samples: sample 1 (n = 322; 137 male, 185 female) verified the linear distances delimited by anatomical landmarks in soft tissue. The sample 2 (n = 108; 40 male, 68 female), verified the proportions among the height of the vermilion borders, width of the mouth, and linear distances between craniometric landmarks in hard tissues, both from a Brazilian database. The measurements were completed using OsiriX, and the results were analyzed by means of descriptive statistics at a level of significance of 5%. The height of the vermilion borders corresponded to approximately 26% of the width of the mouth. The width of the mouth increased over the course of time in men and remained stable in women. In men, a mean intercanine distance of 75% of the total mouth’s width was found; for women, it was 80%. The parameters of the relations between soft and hard tissues in the oral cavity region presented that the distance between landmarks ID-SM (Infradentale-Supramentale) corresponded to 55% of the height of the vermilion borders of the mouth for both sexes, while the distance between landmarks PM-SD (Philtrum medium-Supradentale) corresponded to 85% in men and 88% in women. Mean values of 97% of the width of the mouth in women and 93% in men were attributed to the distance between the mentonian foramina. It was not possible to estimate the height of the labial vermilion borders by the bone measurements, FIs-Fli (Foramen incisivus superius-inferius) and NS-GN (Nasospinale-Gnathion). Profound knowledge of the anatomy and morphology of the oral cavity may contribute to increasing the precision of FFRs and help with human identification.

Assessment of accuracy and recognition of three-dimensional computerized forensic craniofacial reconstruction

“…Computational systems are dependent on facial templates, mean tissue depth markers, and specific population data [ 2 , 27 ]. In this study, soft tissue thickness markers [ 1 ], lip prediction [ 17 ] and nose tip prediction methods [ 15 ] were used from studies with Brazilians in order to apply regional measures for better reconstruction efficiency [ 21 , 24 , 27 ].…”

“…Mouth: The inter-canine distance is estimated as 75% of the total mouth width [ 16 ]. The height of the lips vermillion is 26% of the width [ 17 ]. The lower and upper lip intersection should be placed in the lower section of the upper central incisor [ 18 ].…”

Evaluation of the cone-beam computed tomography accuracy in measuring soft tissue thickness in different areas of the jaws

“…For proper reconstruction of the human face, it is necessary to know the mean thickness of the soft tissue, especially in the areas of the face and scalp that are used in the reconstruction. [1011]…”

Computer-Aided Facial Reconstruction of “Mary-Magdalene” Relics Following Hair and Skull Analyses

“…Prediction of nasal morphology from the skull using the Rynn/Wilkinson/Peters method and Gerasimov/ Lebedinskaya method, an anthropometric facial reconstruction method based on cylinders and soft tissues depth landmarks (so-called "American method") and 3D muscles relocation (socalled Russian anatomical method), taking into account the latest updates and the latest technological advances. [7][8][9][10][11][12][13][14][15][16] The bony structure is the key to the facial volume, and the cylindrical depth markers only propose a mean range for the soft tissues that can go from obese to slim. The difference between them only affects the inferior part of the face, cheeks, and neck.…”