Facial Norms Research Articles

Shape Analysis of the Facebase 3D Facial Norms Dataset Reveals Sexual Dimorphism in Human Faces in Juveniles, Adolescents and Adults

One of the major goals of the 3D Facial Norms Project is to create a large publically available database of 3D facial images and measurements from healthy human subjects. This dataset provides an unparalleled opportunity for the study of human facial shape. The current sample size of almost 1,000 subjects allows us to immediately address questions on a range of topics, including sexual dimorphism and changes over the lifespan. Anthropologists have long known that the human facial shape is sexually dimorphic; our question is: when does facial sexual dimorphism present itself during ontogeny? We broke our sample into three age groups, 19–40 (n = 722), 11–18 (n = 90) and 3–10 (n = 119). These groups represent roughly before, during and after puberty. We hypothesize that facial differences between the sexes would first emerge in the 11–18 group and become more divergent in the 19 – 40 group. Shape was assessed using geometric morphometrics. The results indicate that sexual dimorphism is detectable even in the youngest group (Procrustes distance (P‐dist) between male and female mean shapes: 0.0148, p = 0.017). The means shapes are also different between males and females among the 11–18 age group (P‐dist = 0.0208, p < 0.0001) and the difference is largest in the adult sample (P‐dist = 0.0215, p < 0.0001). These results have implications on our understanding of the drivers of sexual dimorphism in human faces.Grant Funding Source: This work was supported by NIH Grant number 1U01DE020078 to SMW

The perception of facial aesthetics in a young Spanish population

Improved facial aesthetics is one aim of orthodontic treatment. This study was designed to determine if the faces considered more beautiful in a young population exhibit the same parameters used by orthodontists to assess successful results. A panel of 34 laypeople (30 females and 4 males) evaluated a set containing one frontal, one frontal during smiling, and one profile photograph of 89 students (77 females and 12 males) on a 5-point attractiveness scale, in relation to a set of reference photographs. For each photographic set, the mean and final scores were calculated. Once the sample was established, 11 subjects (9 females and 2 males) with the highest final facial aesthetic score were selected and cephalometric analysis was performed. All cephalometric measurements were within the norm for the total sample. When the sample was divided by gender, Wilcoxon's W non-parametric test showed significant differences between the male and female photographs; while females tended to a Class II malocclusion, with the mandible slightly retrusive to the maxilla, males tended to a Class III and showed a straighter profile with a prominent chin; the face height ratio was higher in males. There were no significant differences between genders for lower lip to E plane. The findings show that the faces considered more attractive fulfilled the cephalometric and facial norms.

Predicting face shape from the skull using a combined NMR and stereophotographic image database of living individuals

Facial reconstruction is an artistic process with a limited scientific basis. It is a last resort in human identification inwhich an approximate facial appearance is produced fromthe skull in the hope that a resultant candidate identity might be confirmed by other means such as DNA or dental records. The aim of this investigation was to establish whether contemporary medical and stereophotographic imaging methods could be combined to predict face shape from the skull and to assess whether they can be used to reassess current guidelines for the positioning of facial features and other norms in forensic facial reconstruction. A database was collected from 60 individuals (30 male and 30 female) of predominantly White ancestry, consisting of an MRI scan of the volunteer's head and face, and corresponding 3-D stereophotographic and laser-scanned facial surface images. The skull and face surfaceswere landmarked in 3-D at up to 30 traditional anthropometric points. Accuracy in facial landmark positioning in laser, stereophotograph, and MR imageswas compared. A comparative analysis of hard and soft tissue landmarks was used to develop a method of predicting soft tissue landmark position and tissue depth from the skull of an unknown individual. Finally, the combined datasetswere used to produce a revised set of guidelines for positioning and proportions of soft-tissue features.

Cosmetic surgery of the lips and facial rejuvenation

Cosmetic surgery to rejuvenate the aging face including surgical procedures to augment and rejuvenate the lips, will be discussed. Oral and maxillofacial surgeons are in a unique position to evaluate and manage patients seeking facial rejuvenation and cosmetic treatment. Facial cosmetic surgery represents a natural extension and a complement to our orthognathic skills. Most of our treatment decisions regarding orthognathic procedures are predicated on existing facial esthetic norms and cephalometric analysis. The oral and maxillofacial surgeon is also able to provide esthetic services on a routine basis in an outpatient setting using local anesthesia with intravenous sedation. There are a number of methods and techniques used to augment, recontour, or rejuvenate the lips and the face. These include implantation of alloplastic materials, grafting of autologous tissues, and recontouring of adjacent hard and soft tissues. We will discuss patient selection, augmentation materials, anesthetic technique, operative technique, and postoperative management associated with the procedures. This presentation is intended to be an introduction and brief overview of procedures utilized in my practice that can easily be incorporated into the practice of most oral and maxillofacial surgeons.