3D Modeling of craniofacial ontogeny and sexual dimorphism in children

Abstract

Background The range of normal variation of growth and development of the craniofacial region is of direct clinical interest but incompletely understood. Here we develop a statistical model of craniofacial growth and development to compare craniofacial ontogeny between age groups and sexes and pilot an approach to modeling that is relatively straightforward to apply in the context of clinical research and assessment. Methods The sample comprises head surface meshes captured using a 3dMD five‐camera system from 65 males and 47 females (range 3–20 years) from the Headspace project, Liverpool, UK. The surface meshes were parameterized using 16 anatomical landmarks and 59 semilandmarks on curves and surfaces. Modes and degrees of growth and development were assessed and compared among ages and sexes using Procrustes based geometric morphometric methods. Results Regression analyses indicate that 3–10 year olds undergo greater changes than 11–20 year olds and that craniofacial growth and development differs between these age groups. The analyses indicate that males extend growth allometrically into larger size ranges, contributing substantially to adult dimorphism. Comparisons of ontogenetic trajectories between sexes find no significant differences, yet when hypermorphosis is accounted for in the older age group there is a significant residual sexual dimorphism. Conclusions The study adds to knowledge of how adult craniofacial form and sexual dimorphism develop. It was carried out using readily available software which facilitates replication of this work in diverse populations to underpin clinical assessment of deformity and the outcomes of corrective interventions.

A human craniofacial life‐course: Cross‐sectional morphological covariations during postnatal growth, adolescence, and aging

“…Gender differences of size were established well before puberty and our study suggests that males experienced subtly different patterns of brain and of cranial aging as well as growth. These findings are consistent with recent work published by Smith et al (2020;Smith, Duncan, Pears, Profico & O'Higgins, 2021) as well as Milella et al (2021). We find no evidence that the aged adult cranium is more variable due to, for example, fragility nor that covariations were any weaker or stronger compared with middle aged adults.…”

“…Earlier work suggests that sexual dimorphism of the anterior cranial base is established during childhood while that of the face emerges later, around puberty (Ursi, Trotman, McNamara Jr, & Behrents, 1993). More recently, Smith et al's (2020) analyses of surface landmarks has suggested that craniofacial sexual dimorphism is mostly size related and that males follow an extended growth trajectory (hypermorphosis). This size offset has also been confirmed in a recent study of skeletal landmarks (Milella, Franklin, Belcastro, & Cardini, 2021) with males, on average, more prognathic and dolichocephalic compared with females.…”

Applications of 3D Photography in Craniofacial Surgery

“…Smith et al [ 22 ] used the much larger Headspace dataset, which was used to construct the LYHM and both confirmed the above finding and also noted a second period of accelerated aging in females in the late twenties and early thirties. In a different study, but also using the same dataset, Smith et al [ 23 ] also explored changes in growth and form in children of both sexes and added to an understanding of the extent and timing of appearance of hypermorphism in the male craniofacial form.…”

Sexual dimorphism in human midfacial growth patterns from newborn to 5 years old based on computed tomography

“…The problem of the ontogenetic origin of sexual dimorphism (SD) in mid‐facial form has been studied intensively during the last decades (Broadbent et al, 1975; Bulygina et al, 2006; Dean et al, 2000; Farkas, Posnick, & Hreczko, 1992; Farkas et al, 1992a, 1992b; Humphrey, 1998; Likus et al, 2014; Matthews, 2018; Riolo et al, 1974; Smith et al, 2021; Tutkuviene et al, 2016). Though the bulk of this research was concerned with sex‐specific growth patterns in older children and adolescents in connection to the pubertal growth spurt, it has gradually become clear that SD begins to play an important role in craniofacial variation well before puberty (Delye et al, 2015; Humphrey, 1998; Schutkowski, 1993; Ursi et al, 1993; Viðarsdottir, 1999; Wheat, 2015).…”