Impact of Head Position on Facial Soft Tissue Thickness: An Ultrasound Study in the Slovak Population
by
, , and
Zuzana Kozáková
, 
Simona Sulis
*,
Darina Falbová
,
Lenka Vorobeľová
,
Mária Matláková
,
Radoslav Beňuš
and
Petra Švábová
* Department of Anthropology, Comenius University Bratislava, Ilkovičova 3278/6, 841 04 Bratislava, Slovakia
*
Authors to whom correspondence should be addressed.
Forensic Sci. 2025, 5(1), 5; https://doi.org/10.3390/forensicsci5010005
Submission received: 26 November 2024
/
Revised: 4 January 2025
/
Accepted: 13 January 2025
/
Published: 20 January 2025
Abstract
:Background/Objectives: Facial soft tissue thickness (FSTT) data are extensively utilized in forensic and medical sciences, serving as a foundational element for craniofacial reconstruction and identification methods. This study aims to analyze the differences in FSTT measurements between upright and supine positions in living subjects. Methods: The study sample consisted of 121 participants aged 20 to 86 years from Slovakia. Biological sex and age data were collected. FSTT measurements were taken at eight medial facial line landmarks and eight bilateral landmarks using a non-invasive General Electric LOGIQe R7 ultrasound device. Results: The results indicate that the head position significantly influenced more than half of the landmarks, with mean differences not exceeding 1.31 mm. Most FSTT values were higher in the horizontal position. Younger males and females exhibited significant differences in FSTT across various regions, including the eye, cheek, nose and mouth, with discrepancies in the forehead, chin, and cheek regions among younger males. In older males, only the gonion region showed a significant position-related difference, while older females demonstrated substantial FSTT changes at five landmarks, with the largest difference (1.31 mm) observed at the mandible, accounting for 15.74% of the mean FSTT. Compared to younger groups, older females exhibited higher FSTT values in the upright position. Conclusions: These findings suggest that measurements in an upright position may be more suitable for facial reconstruction, as positional changes in FSTT can occur in both positive and negative directions.
1. Introduction
Facial soft tissue thickness (FSTT) plays a crucial role in forensic and medical sciences, particularly in craniofacial reconstruction and identification. These measurements provide essential data for reconstructing facial features and enhancing methods like craniofacial superimposition [1]. When traditional identification techniques—such as dactyloscopy, dental record comparison, or DNA analysis—fail due to insufficient material or instability [2], FSTT becomes an invaluable tool in individual identification [3].
Facial soft tissue thickness values are highly population-specific [4] and influenced by various factors such as age, sex, body mass index (BMI), and external elements like lifestyle (skin care, exercise), environmental conditions (UV exposure), traumas and disease (superficial soft tissue injuries, malocclusions, fractures, abscesses) [3,5,6,7]. Understanding these population-specific traits is critical for improving the accuracy of forensic reconstructions and anthropometric studies [4]. The facial soft tissues, comprising skin, subcutaneous connective tissue, adipose tissue, and muscle layers, are supported by underlying bone structures [1,8,9]. Their thickness varies due to internal (e.g., aging, hormonal changes) and external factors (e.g., diet, smoking). Aging leads to anatomical changes in both bone and soft tissue, such as atrophy, bone remodeling [5], and tissue redistribution, which can affect FSTT values. Age causes anatomical transformations in the face; therefore, it can be used as a basic categorization of individuals. Facial features preferentially conditioned by age changes are facial shape, skin color and texture [10,11]. Bone tissue remodeling in the aging face includes the reduction in tissue in the zygomatic bone, the forward displacement of the chin resulting from the shortening and tilting of the mental protuberance, and the increasing angle of the mandibular ramus [12]. Facial soft tissue thicknesses and their changes depend on the age of the individual. Differences range from 1 to 2 mm, especially in the upper lip region (midphiltrum, alare, fossa canina), the occlusal line, the region of the lower orbital rim (orbitale) and the angulus mandibulae (gonion) [13]. Differences between sexes with increasing age are manifested primarily in differences in the soft tissues and skin thicknesses and hormonal activity, often associated with menopause in females [11]. In females, FSTT remains relatively stable until the age of 60, after which the FSTT values decline rapidly, with some regions of the face experiencing up to 50% reduction [14]. Notable differences between sexes have been observed in the zygomatic region, with variations exceeding 2 mm in the mean FSTT values. Differences ranging from 1 to 1.5 mm were observed in the mouth region (midphiltrum, alare, fossa canina), where males exhibit thicker soft tissues. Females have thicker facial soft tissues, particularly in the cheek and orbital regions [13].
Several methods exist for measuring FSTT, including needle puncture on cadavers, computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound [1]. Among these, ultrasound has gained popularity due to its non-invasive nature, portability, absence of radiation, and cost-effectiveness. Ultrasound measurement allows for monitoring changes in soft tissues caused by various factors, since the face and neck are the two main areas of the body where changes due to age, sex and external factors, such as smoking and diet, are most noticeable. Ultrasound imaging is a modern method that has been increasingly used in recent years [15]. Ultrasound uses high-frequency sound waves, thus allowing imaging of the various structures under investigation. By using the reflection of sound waves off the structures as tissue density changes and transforming these data, a computer image is produced [16]. From the resulting image, it is possible to measure the distances between tissues or the dimensions of the structures under investigation [17]. Ultrasound can be employed in at least two forms: A-mode and B-mode. A-mode represents “amplitude ultrasonography” and uses the reflection time of the pulse from the tissues to the probe for measurement. B-mode represents “brightness modulation” and uses not only the pulse reflection time, but also the strength of the reflected pulse from the tissues to the probe, for recording, which increases the accuracy of the FSTT measurement. Also, most B-mode ultrasound devices are user-friendly in terms of their simplicity, size, and thus portability, making them the preferred and most widely used choice for measurements [16]. Recent advancements in B-mode ultrasonography have improved the accuracy and usability of FSTT measurements in living individuals. However, the reliability of these measurements can be influenced by factors like the operator’s skill and the body position during measurement [18]. In addition to this well-known use of ultrasound, there are other methods. These include the method of using ultrasound as a facial scanning tool, without any direct interaction of the ultrasound probe with the surface of the face. The ultrasound transducer moves away from the face and only records the individual FSTTs in the measured facial landmarks [19].
This study aims to investigate the differences in FSTT between upright and supine positions across different age and sex groups within the Slovak population. It also seeks to expand the dataset on FSTT in this population, building on prior studies conducted with CT and ultrasound methods.
2. Materials and Methods
2.1. Sample Description and Anthropometric Measurements
The study analyzed 121 individuals of White European origin, comprising 77 females and 44 males, divided into younger and older age categories (Table 1). Female participants in the younger group (n = 39) were aged 20–25 years (mean = 22.77 ± 1.18 years), while the older group (n = 38) was aged 46–5 years (mean = 63.84 ± 9.63 years). Male participants in the younger group (n = 26) were aged 20–24 years (mean = 22.73 ± 1.02 years), and the older group (n = 18) was aged 48–86 years (mean = 64.35 ± 9.30 years). Basic anthropometric data, including sex, age, stature and weight, were recorded for each participant.
The measurements were taken in the morning hours for the more accurate measurement of body weight and stature [20].
2.2. Ultrasound Measurement Protocol
Measurements were conducted using a General Electric LOGIQe R7 (GE HealthCare, Bratislava, Slovakia) ultrasound device with a probe frequency of approximately 20 MHz. B-mode ultrasound, known for its high accuracy and user-friendly design, was selected for this study (Figure 1). The probe was applied to each anthropometric landmark with a thin layer of hypoallergenic sonographic gel to ensure consistent image quality.
The B-mode ultrasound setup has also been used by De Greef et al. [2], Bailie et al. [21] and Stephan and Preisler [22] in their research. This measurement method poses no risk to the human body, the ultrasound examination is non-invasive, and there is no irradiation of the human body as with other methods; therefore, it is possible to measure participants repeatedly [23,24]. The General LOGIQe R7 ultrasound device is also portable and costs less than CT, CBCT or MRI, and the fact that ultrasound imaging does not use X-rays also contributes to the advantages of measuring with it [16,24]. Helmer [25] contributed with his soft tissue research to bring the measurement of FSTT with ultrasound to the fore [26]. The same device was also used in the study by Švábová et al. [27] to measure the FSTT in the Slovak population.
Participants were measured in both upright and supine positions, starting with the upright position followed by the supine position. In the upright position, participants sat comfortably with a neutral facial expression, maintaining the Frankfurt Horizontal (FH) plane. In the supine position, participants laid on their backs without movement. Measurements were taken in millimeters at eight medial and eight bilateral facial landmarks based on established protocols from Jia et al. [28] and Peckmann et al. [29]. For the purpose of this study, eight anthropometric landmarks were measured in the midline of the face—metopion, glabella, nasion, rhinion, midphiltrum, supramental, pogonion and gnation. Subsequently, eight paired landmarks were measured on the right and left halves of the face—supraorbital, infraorbital, alare, fossa canina, malare, zygomatic, midmandible and gonion (Figure 2). The study by Švábová et al. [27] (Table 2) was used to define the individual anthropometric landmarks.
2.3. Statistical Analysis
Facial soft tissue thickness measurements were recorded in Microsoft Excel and analyzed using IBM SPSS Statistics (v. 26). The Kolmogorov–Smirnov test was used to verify data normality. Nonparametric tests were applied for further analysis. The Mann–Whitney U test assessed differences between sexes and intergroup differences, while the Wilcoxon test compared positional differences. Statistical significance was set at p < 0.05.
3. Results
After the initial analysis and division of the dataset into age categories (Table 1), where mean, maximum and minimum age values were defined, FSTT values in the whole dataset were analyzed (Table 2). Regardless of sex and age category, significant differences were found between the FSTT mean values in both measured positions (supine and upright). These differences were most prominent in the forehead, eye and cheek regions. Differences caused by different head positions during the measurements were calculated by subtracting the mean values in the individual anthropometric landmarks in the order of the taken measurements, i.e., upright minus supine. At the glabella, supramentale, pogonion and fossa canina landmarks, the differences caused by different head positions reached up to 1.10 mm. Other significant landmarks, including the metopion, rhinion, supraorbital, infraorbital, zygomatic and gonion, exhibited higher mean values in the supine position. The mean differences at these landmarks ranged from 0.11 mm at the metopion landmark (forehead region) to 0.84 mm at the infraorbital landmark.
After evaluating the FSTT in the entire dataset, younger and older age groups were statistically analyzed. Differences in FSTT measurements between sexes within each age group, influenced by the participant’s head position, were then investigated. In the younger female age group (Table 3), significant differences in mean FSTT values were observed in the eye, nose, cheek and mouth regions due to the effect of head position. The differences in mean values did not exceed 0.89 mm, with the largest discrepancy noted at the fossa canina landmark. In the supine position, the majority of measured anthropometric landmarks exhibited higher mean values, except for the glabella, supramentale, fossa canina, malare and gonion landmarks.
In younger males, significant differences were identified at five anthropometric landmarks in the forehead, cheek and chin regions (Table 3). The differences in mean FSTT values ranged from 0.00 mm at the nasion landmark to 0.93 mm at the pogonion landmark. Similar to females, most mean FSTT values in males were higher in the supine position due to the effect of gravity.
When comparing FSTT mean values in older females (Table 4), significant differences were observed at five anthropometric landmarks: glabella, supramentale, pogonion, fossa canina and midmandible. Most of these differences occurred in the lower half of the face and around the mouth region, except for the glabella landmark. The largest difference in mean FSTT values was at the midmandible landmark, reaching 1.31 mm. Compared to younger females, older females exhibited higher FSTT values in the upright position. In older males (Table 4), significant differences were noted only at the gonion landmark in the mandible region. No significant landmarks showing differences common to both male age groups were found.
4. Discussion
This study investigated the impact of body position on FSTT measurements across age and sex groups within groups in a Slovak population using the non-invasive ultrasound method. Significant differences in FSTT were observed between supine and upright positions at several anthropometric landmarks, particularly in the forehead, cheek, and chin regions. These findings highlight the importance of standardized measurement protocols for FSTT data collection and its implications for forensic and clinical applications.
Body position has been shown to impact FSTT values due to the effect of gravity, which can redistribute soft tissues. In the supine (horizontal, lying) position compared to the upright (vertical, sitting) position, facial soft tissues shift downward and laterally, causing changes in FSTT at the lateral anthropometric landmarks, resulting in differences in mean values ranging from 1.2 mm to 3 mm. Similar differences have been noted in the mouth region and nasolabial groove (alare landmark), with FSTT mean differences ranging from 1 mm to 2.4 mm. These variations tend to increase with age, though they do not exceed a 4 mm threshold in the midline of the face [30,31]. Bailie [21] established the differences in FSTT due to the head position at anthropometric landmarks in different regions of the face, including in the chin region (menton), where the value ranged around 2.6 mm, the zygomatic region (zygomatic) where they ranged around 0.7 mm, and the mandible region (gonion) where they ranged around 1.1 mm. According to Bulut et al. [32], the differences in FSTT values in the lateral facial margins (supraglenoid landmark) due to head position can be up to 10 mm. It is because of the resulting differences in the FSTT that Munn and Stephan [30] recommend measuring in the upright position if the data collected are to be used in craniofacial reconstruction. While the supine position may cause tissue displacement, upright measurements are considered more representative for applications such as forensic craniofacial reconstruction. Understanding these positional differences is crucial for standardizing measurement protocols [16,31]. Several midsagittal landmarks (metopion, rhinion, nasion, gnation) had higher mean values in the supine position than in the upright position. These results are attributed to the high intrapersonal variability of FSTT values, as well as the different facial structure and different representations of facial muscle and fat components.
The results align partially with those from the study of Baillie et al. [21], in which the significant positional differences were observed in White European females at the infraorbital, gnathion, zygomatic, and gonion landmarks using ultrasound. However, our study did not find significant differences at these landmarks. Baillie et al. [21] emphasized that upright measurements may be more appropriate for FSTT assessments, which aligns with our findings that positional effects should not be overlooked.
Stephan and Preisler also found significant differences in positional measurements, particularly in younger individuals (18–30 years), at the infraorbital, zygomatic, midmandible, and gonion landmarks. These differences, while statistically significant, did not exceed 1.5 mm in the younger group, consistent with our findings of positional variability in younger participants. In the older age group (˃37 years), significant differences were only found at the midmandible landmark (2 mm), the values of which reached the greatest thicknesses in the upright position [22].
In comparison, Munn and Stephan [30] used stereo photogrammetry to evaluate positional effects, and noted that the most affected regions were the cheeks, eye areas, and mouth. Differences ranged from 0.03 mm to 2.90 mm in younger participants (<50 years) and were more pronounced in older individuals (>50 years). These differences ranged from 0.13 mm to 1.04 mm in the medial line landmarks, and from 0.06 mm to 3.93 mm in the paired lateral landmarks. The largest differences due to position were in the same regions as in the younger age group, with the mouth region added [30]. These findings are consistent with our results, where younger participants showed significant differences in more landmarks than older participants, and positional effects were particularly pronounced in the cheek and eye regions. Bulut et al. [32] found significant positional differences exceeding 2 mm in the zygomatic, nasolabial, and mandible regions using 3D scans. Although our findings in these regions showed differences, the magnitude of variability was less pronounced, possibly due to differences in imaging modalities.
Regarding differences between sexes, Perzová [33] reported significant differences in six landmarks between sexes, but these differences were negligible in our study, with mean FSTT variations between males and females ranging from 0.07 mm to 0.87 mm. Similar findings were noted by Panenková et al. [4], who reported thicker FSTT values in males except for the lateral orbital landmark (malare). These variations reinforce the importance of population-specific data for FSTT measurements and their forensic applications. Differences between sexes and in different age groups are also confirmed in young individuals, where Wilkinson (2002) confirmed an increase in FSTT in males with increasing age mainly in the cheeks and around the mouth [34].
Technical error of measurement (TEM) was analyzed and evaluated using the same data set as was used by Švábová et al. [27] in their study, where 10 participants were measured twice or repeatedly after 3 days. Measurements were taken by the same investigator to correctly determine interpersonal precision. Švábová et al. [27] also encouraged the consideration of BMI in their study, as this has been shown to be a significant factor influencing differences between sexes, in particular in the population studied, influencing a large majority of FSTT in the measured landmarks [27,35].
Limits of the Study and Further Recommendations
The smaller sample size in the older male group may have limited the statistical power for detecting differences in FSTT in this group. Future research should focus on expanding the dataset to include larger and more diverse populations, particularly older male participants, to ensure broader applicability. Although BMI was not analyzed as a factor in this study due to the small sample size, which, when divided into even smaller BMI categories, could compromise the results, future studies could benefit from a detailed examination of the relationship between BMI and the measurement of FSTT with respect to the head position. Additionally, longitudinal studies could investigate how positional differences in FSTT evolve with aging or changes in BMI.
5. Conclusions
This study analyzed facial soft tissue thickness values across two head positions in a Slovak White European population using non-invasive ultrasound. The findings demonstrated that body position significantly influences FSTT values, with positional differences observed in nearly 60% of the measured landmarks, particularly in younger participants. In young females, significant differences were found in the midline (glabella, rhinion, supramental) landmarks and in landmarks of the lower part of the face at the midmandible and gonion. In older females, significant differences were found in the same regions as in younger females. In younger males, significant differences were noted at the zygomatic landmark, the fossa canina, as well as in the midline at the metopion landmark. In the older age group, significant differences in average FSTT values were found in males only at the gonion landmark. These results underscore the necessity of standardized measurement protocols to account for positional effects in FSTT data collection, particularly for forensic and clinical applications. This study contributes valuable reference data for the Slovak population, and emphasizes the importance of considering body position when interpreting FSTT values.
Author Contributions
Conceptualization, Z.K. and M.M.; methodology, Z.K. and M.M.; software, P.Š., Z.K. and D.F.; validation, L.V., P.Š. and R.B.; formal analysis, D.F. and S.S.; investigation, Z.K. and P.Š.; resources, S.S.; data curation, Z.K. and M.M.; writing—original draft preparation, Z.K. and P.Š.; writing—review and editing, S.S., D.F., L.V. and R.B.; visualization, S.S. and D.F.; supervision, P.Š. and R.B.; project administration, P.Š.; funding acquisition, L.V. and P.Š. All authors have read and agreed to the published version of the manuscript.
Funding
This study was supported by the Cultural and Educational Grant Agency (KEGA 046UK-4/2023) of the Ministry of Education, Science, Research and Sport of the Slovak Republic.
Institutional Review Board Statement
The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee for Research on Human Subjects at the Faculty of Natural Sciences, Comenius University in Bratislava, Slovakia (protocol code ECH19026, approved on 2 March 2023).
Informed Consent Statement
Informed consent was obtained from all subjects involved in the study.
Data Availability Statement
The research data are not shared.
Conflicts of Interest
The authors declare no conflicts of interest.
References
- Kos, J. Přehled Topografické Anatomie; Stingl, J., Ed.; Karolinum: Prague, Czech Republic, 2014. [Google Scholar]
- De Greef, S.; Claes, P.; Vandermeulen, D.; Mollemans, W.; Suetens, P.; Willems, G. Large-Scale In-Vivo Caucasian Facial Soft Tissue Thickness Database for Craniofacial Reconstruction. Forensic Sci. Int. 2006, 159, S126–S146. [Google Scholar] [CrossRef] [PubMed]
- Thakur, S.; Sehrawat, J.S. Age and Sex Dependent Differences in Midline Facial Soft Tissue Thicknesses Measured on MRI Scans of Northwest Indian Subjects: A Forensic Anthropological Study. Egypt. J. Forensic Sci. 2023, 13, 38. [Google Scholar] [CrossRef]
- Panenková, P.; Beňuš, R.; Masnicová, S.; Obertová, Z.; Grunt, J. Facial Soft Tissue Thicknesses of the Mid-Face for Slovak Population. Forensic Sci. Int. 2012, 220, 293.e1–293.e6. [Google Scholar] [CrossRef]
- Beth, H. Aesthetic Procedures: Nurse Practitioner’s Guide to Cosmetic Dermatology; Springer International Publishing: Irvine, CA, USA, 2020. [Google Scholar]
- Manhein, M.H.; Listi, G.A.; Barsley, R.E.; Musselman, R.; Barrow, N.E.; Ubelaker, D.H. In vivo facial tissue depth measurements for children and adults. J. Forensic Sci. 2000, 45, 48–60. [Google Scholar] [CrossRef]
- El-Mehallawi, I.H.; Soliman, E.M. Ultrasonic assessment of facial soft tissue thicknesses in adult Egyptians. Forensic Sci. Int. 2001, 117, 99–107. [Google Scholar] [CrossRef] [PubMed]
- Cotofana, S.; Lachman, N. Anatomy of the Facial Fat Compartments and their Relevance in Aesthetic Surgery. J. Dtsch. Dermatol. Ges. 2019, 17, 399–413. [Google Scholar] [CrossRef]
- Kahn, J.L.; Wolfram-Gabel, R.; Bourjat, P. Anatomy and Imaging of the Deep Fat of the Face. Clin. Anat. 2000, 13, 373–382. [Google Scholar] [CrossRef]
- Kaur, M.; Garg, R.K.; Singla, S. Analysis of facial soft tissue changes with aging and their effects on facial morphology: A forensic perspective. Egypt. J. Forensic Sci. 2015, 5, 46–56. [Google Scholar] [CrossRef]
- Nkengne, A.A. Prédire l’âge de Personnes à Partir de Photos Du Visage: Une Étude Fondée Sur La Caractérisation et l’analyse de Signes Du Vieillissement; Université Pierre et Marie Curie: Paris, France, 2008. [Google Scholar]
- Toledo Avelar, L.E.; Cardoso, M.A.; Santos Bordoni, L.; De Miranda Avelar, L.; De Miranda Avelar, J.V. Aging and Sexual Differences of the Human Skull. Plast. Reconstr. Surg.-Glob. Open 2017, 5, e1297. [Google Scholar] [CrossRef] [PubMed]
- De Greef, S.; Vandermeulen, D.; Claes, P.; Suetens, P.; Willems, G. The Influence of Sex, Age and Body Mass Index on Facial Soft Tissue Depths. Forensic Sci. Med. Pathol. 2009, 5, 60–65. [Google Scholar] [CrossRef]
- Limbert, G.; Masen, M.A.; Pond, D.; Graham, H.K.; Sherratt, M.J.; Jobanputra, R.; McBride, A. Biotribology of the Ageing Skin—Why We Should Care. Biotribology 2019, 17, 75–90. [Google Scholar] [CrossRef]
- Alimova, S.; Sharobaro, V.; Yukhno, A.; Bondarenko, E. Possibilities of Ultrasound Examination in the Assessment of Age-Related Changes in the Soft Tissues of the Face and Neck: A Review. Appl. Sci. 2023, 13, 1128. [Google Scholar] [CrossRef]
- Meikle, B.; Stephan, C.N. B-mode Ultrasound Measurement of Facial Soft Tissue Thickness for Craniofacial Identification: A Standardized Approach. J. Forensic Sci. 2020, 65, 939–947. [Google Scholar] [CrossRef]
- Hrazdira, I. Biofyzikální Základy Ultrasnografie: Jak Pracovat s Ultrazvukovým Diagnostickým Přístrojem; Univerzita Palackého: Olomouc, Czech Republic, 2011; ISBN 978-80-244-2895-6. [Google Scholar]
- Masnicová, S.; Beňuš, R.; Panenková, P. Rekonštrukcia Podoby Tváre z Lebky; Akadémia policajného zboru v Bratislave: Bratislava, Slovakia, 2011. [Google Scholar]
- Smith, S.L.; Throckmorton, G.S. A new technique for three-dimensional ultrasound scanning of facial tissues. J. Forensic Sci. 2004, 49, JFS2003203-7. [Google Scholar] [CrossRef]
- Krishan, K.; Sidhu, M.C.; Kanchan, T.; Menezes, R.G.; Sen, J. Diurnal Variation in Stature—Is It More in Children or Adults? Biosci. Hypotheses 2009, 2, 174–175. [Google Scholar] [CrossRef]
- Baillie, L.J.; Muirhead, J.C.; Blyth, P.; Niven, B.E.; Dias, G.J. Position Effect on Facial Soft Tissue Depths: A Sonographic Investigation. J. Forensic Sci. 2016, 61, S60–S70. [Google Scholar] [CrossRef] [PubMed]
- Stephan, C.N.; Preisler, R. In Vivo Facial Soft Tissue Thicknesses of Adult Australians. Forensic Sci. Int. 2018, 282, 220.e1–220.e12. [Google Scholar] [CrossRef] [PubMed]
- Thiemann, N.; Keil, V.; Roy, U. In Vivo Facial Soft Tissue Depths of a Modern Adult Population from Germany. Int. J. Leg. Med. 2017, 131, 1455–1488. [Google Scholar] [CrossRef] [PubMed]
- Somos, C.P.; Rea, P.M.; Shankland, S.; Kranioti, E.F. Medical Imaging and Facial Soft Tissue Thickness Studies for Forensic Craniofacial Approximation: A Pilot Study on Modern Cretans. In Biomedical Visualisation; Rea, P.M., Ed.; Advances in Experimental Medicine and Biology; Springer International Publishing: Cham, Switzerland, 2019; Volume 1138, pp. 71–86. ISBN 978-3-030-14226-1. [Google Scholar]
- Helmer, R. Schäldelidentifizierung Durch Elektroniesche Bildmischung: Zugleich Ein Beitrag Zur Konstitutionsbiometrie Und Dickenmessung Der Gesichtweichteile; Kriminalistik-Verlag: Heilderberg, Germany, 1984. [Google Scholar]
- Chaimongkhol, T.; Mahakkanukrauh, P. The Facial Soft Tissue Thickness Related Facial Reconstruction by Ultrasonographic Imaging: A Review. Forensic Sci. Int. 2022, 337, 111365. [Google Scholar] [CrossRef]
- Švábová, P.; Matláková, M.; Beňuš, R.; Chovancová, M.; Masnicová, S. The Relationship between Biological Parameters and Facial Soft Tissue Thickness Measured by Ultrasound and Its Forensic Implications. Med. Sci. Law 2024, 64, 23–31. [Google Scholar] [CrossRef] [PubMed]
- Jia, L.; Qi, B.; Yang, J.; Zhang, W.; Lu, Y.; Zhang, H.-L. Ultrasonic Measurement of Facial Tissue Depth in a Northern Chinese Han Population. Forensic Sci. Int. 2016, 259, 247.e1–247.e6. [Google Scholar] [CrossRef]
- Peckmann, T.R.; Harris, M.; Huculak, M.; Pringle, A.; Fournier, M. In Vivo Facial Tissue Depth for Canadian Mi’kmaq Adults: A Case Study from Nova Scotia, Canada. J. Forensic Leg. Med. 2015, 29, 43–53. [Google Scholar] [CrossRef]
- Munn, L.; Stephan, C.N. Changes in Face Topography from Supine-to-Upright Position—And Soft Tissue Correction Values for Craniofacial Identification. Forensic Sci. Int. 2018, 289, 40–50. [Google Scholar] [CrossRef]
- Smith, S.L.; Throckmorton, G.S. Comparability of radiographic and 3D-ultrasound measurements of facial midline tissue depths. J. Forensic Sci. 2006, 51, 244–247. [Google Scholar] [CrossRef]
- Bulut, O.; Jessica Liu, C.-Y.; Koca, F.; Wilkinson, C. Comparison of Three-Dimensional Facial Morphology between Upright and Supine Positions Employing Three-Dimensional Scanner from Live Subjects. Leg. Med. 2017, 27, 32–37. [Google Scholar] [CrossRef]
- Perzová, B. Analýza Hrúbok Mäkkých Tvárových Tkanív Tváre v Slovenskej Populácii, Katedra Antropológie Prírodovedeckej Fakulty; Univerzity Komenského: Bratislava, Slovakia, 2017. [Google Scholar]
- Wilkinson, C.M. In vivo facial tissue depth measurements for white British children. J. Forensic Sci. 2002, 47, 459–465. [Google Scholar] [CrossRef] [PubMed]
- Ode, J.J.; Pivarnik, J.M.; Reeves, M.J.; Knous, J.L. Bosy Mass Index as a Predictor of Percent Fat in College Athletes and Non-athletes. Med. Sci. Sports Exerc. 2007, 39, 403–409. [Google Scholar] [CrossRef]
Figure 1.
Ultrasound measurement of the metopion landmark in the medial line of the face—the yellow line is the measured FSTT of the landmark, reaching the value of 8.55 mm.
Figure 1.
Ultrasound measurement of the metopion landmark in the medial line of the face—the yellow line is the measured FSTT of the landmark, reaching the value of 8.55 mm.
Figure 2.
The illustration of the anthropometric landmarks used for facial soft tissue thickness measurement (Švábová et al. [22]).
Figure 2.
The illustration of the anthropometric landmarks used for facial soft tissue thickness measurement (Švábová et al. [22]).
Table 1.
Age composition of measured participants.
| Category | N | Min. | Max. | Average | SD |
|---|---|---|---|---|---|
| Younger females | 39 | 20.02 | 25.34 | 22.77 | 1.18 |
| Younger males | 26 | 20.72 | 24.78 | 22.73 | 1.02 |
| Older females | 38 | 46.29 | 85.28 | 63.84 | 9.63 |
| Older males | 18 | 48.76 | 86.88 | 64.35 | 9.30 |
| Whole dataset | 121 | 20.02 | 86.88 | 41.85 | 21.58 |
Abbreviations: N, number of participants in age category; Min, minimal age; Max, maximum age; SD, standard deviation; all values stated in years.
Table 2.
Comparison of facial soft tissue thickness measurements affected by different head positions in the whole dataset regardless sex and age category.
Table 2.
Comparison of facial soft tissue thickness measurements affected by different head positions in the whole dataset regardless sex and age category.
| Anthropometric Landmark | N | Upright Position | Supine Position | Difference Between Positions 1 | z-Value | p-Value | ||
|---|---|---|---|---|---|---|---|---|
| Mean | SD | Mean | SD | (mm) | ||||
| Metopion (mm) | 121 | 4.84 | 0.95 | 4.95 | 0.99 | −0.11 | −2.371 | <0.05 * |
| Glabella (mm) | 121 | 5.13 | 0.92 | 4.83 | 0.76 | 0.30 | −4.594 | <0.05 * |
| Nasion (mm) | 121 | 3.88 | 0.79 | 3.92 | 0.75 | −0.04 | −0.388 | >0.05 |
| Rhinion (mm) | 121 | 3.39 | 0.83 | 3.57 | 0.72 | −0.18 | −2.772 | <0.05 * |
| Midphiltrum (mm) | 120 | 9.37 | 2.09 | 9.35 | 1.86 | 0.02 | −0.261 | >0.05 |
| Supramentale (mm) | 121 | 10.54 | 1.45 | 10.10 | 1.22 | 0.44 | −4.409 | <0.05 * |
| Pogonion (mm) | 121 | 7.64 | 2.45 | 7.36 | 2.14 | 0.28 | −2.183 | <0.05 * |
| Gnathion (mm) | 121 | 5.55 | 1.86 | 5.69 | 1.55 | −0.14 | −1.452 | >0.05 |
| Alare (mm) | 121 | 10.84 | 1.52 | 10.99 | 1.54 | −0.15 | −0.253 | >0.05 |
| Supraorbital (mm) | 121 | 4.82 | 1.80 | 5.41 | 2.47 | −0.59 | −3.253 | <0.05 * |
| Infraorbital (mm) | 121 | 4.84 | 1.52 | 5.68 | 2.07 | −0.84 | −3.131 | <0.05 * |
| Fossa canina (mm) | 121 | 18.04 | 2.47 | 16.94 | 2.71 | 1.10 | −4.329 | <0.05 * |
| Midmandible (mm) | 121 | 6.89 | 3.10 | 6.54 | 2.51 | 0.35 | −1.284 | >0.05 |
| Malare (mm) | 121 | 10.79 | 1.58 | 10.56 | 1.35 | 0.14 | −1.026 | >0.05 |
| Zygomatic (mm) | 121 | 8.89 | 2.14 | 9.41 | 2.15 | −0.52 | −3.296 | <0.05 * |
| Gonion (mm) | 121 | 5.64 | 2.68 | 6.06 | 3.03 | −0.42 | −3.649 | <0.05 * |
Abbreviations: N, total number of participants; p, statistical significance; z-value, statistical value of the test; SD, standard deviation. 1 the minus sign indicates higher average values in the supine position; * statistical significance p < 0.05.
Table 3.
Comparison of the FSTT in two head positions (upright and supine) regarding sex in the younger age category.
Table 3.
Comparison of the FSTT in two head positions (upright and supine) regarding sex in the younger age category.
| Females (N = 39) | Males (N = 26) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Anthropometric Landmark | Upright Position | Supine Position | Difference Between Positions 1 | p-Value | Upright Position | Supine Position | Difference Between Positions 1 | p-Value | ||||
| Mean | SD | Mean | SD | (mm) | Mean | SD | Mean | SD | (mm) | |||
| Metopion (mm) | 4.32 | 0.79 | 4.45 | 0.93 | −0.13 | >0.05 | 4.64 | 0.67 | 4.85 | 0.80 | −0.21 | <0.05 * |
| Glabella (mm) | 4.62 | 0.69 | 4.34 | 0.54 | 0.28 | <0.05 * | 4.79 | 0.68 | 4.50 | 0.59 | 0.29 | <0.05 * |
| Nasion (mm) | 3.63 | 0.68 | 3.73 | 0.71 | −0.10 | >0.05 | 3.87 | 0.71 | 3.87 | 0.75 | 0.00 | >0.05 |
| Rhinion (mm) | 3.17 | 0.68 | 3.56 | 0.64 | −0.39 | <0.001 * | 3.37 | 0.96 | 3.49 | 1.80 | −0.12 | >0.05 |
| Midphiltrum (mm) | 9.80 | 1.34 | 9.64 | 1.43 | 0.16 | <0.05 | 10.55 | 1.82 | 10.63 | 1.67 | −0.08 | >0.05 |
| Supramentale (mm) | 10.20 | 1.40 | 9.38 | 1.13 | 0.82 | <0.001 * | 10.80 | 0.96 | 9.88 | 0.82 | 0.92 | >0.05 |
| Pogonion (mm) | 6.88 | 2.20 | 6.97 | 2.13 | −0.09 | >0.05 | 7.88 | 2.40 | 6.95 | 2.13 | 0.93 | <0.01 * |
| Gnathion (mm) | 5.19 | 1.55 | 5.37 | 1.45 | −0.18 | >0.05 | 4.98 | 1.12 | 5.43 | 1.20 | −0.45 | >0.05 |
| Alare (mm) | 10.25 | 1.20 | 10.58 | 1.47 | −0.33 | >0.05 | 10.55 | 0.88 | 10.63 | 0.57 | −0.08 | >0.05 |
| Supraorbital (mm) | 4.70 | 1.14 | 4.47 | 1.25 | 0.23 | >0.05 | 3.98 | 1.80 | 4.41 | 1.65 | −0.43 | >0.05 |
| Infraorbital (mm) | 4.37 | 0.89 | 4.82 | 1.18 | −0.45 | <0.05 | 4.17 | 0.66 | 4.43 | 1.27 | −0.26 | >0.05 |
| Fossa canina (mm) | 17.25 | 2.41 | 16.36 | 2.33 | 0.89 | <0.001 * | 17.34 | 1.34 | 17.70 | 1.55 | −0.36 | <0.05 * |
| Midmandible (mm) | 5.62 | 2.18 | 5.86 | 2.19 | −0.24 | >0.05 | 5.30 | 1.71 | 5.21 | 1.97 | 0.09 | >0.05 |
| Malare (mm) | 10.55 | 1.88 | 10.24 | 1.43 | 0.31 | >0.05 | 10.87 | 1.24 | 10.68 | 0.92 | 0.19 | >0.05 |
| Zygomatic (mm) | 8.67 | 1.59 | 8.93 | 1.77 | −0.26 | >0.05 | 7.22 | 2.11 | 8.60 | 1.95 | −1.38 | <0.01 * |
| Gonion (mm) | 4.59 | 1.74 | 4.92 | 1.77 | −0.33 | <0.01 | 4.58 | 1.67 | 5.10 | 1.83 | −0.52 | >0.05 |
Abbreviations: N, total number of participants; p, statistical significance; SD, standard deviation. 1 The minus sign indicates higher average values in the supine position; * marks statistical significance, p < 0.05.
Table 4.
Comparison of the FSTT in two head positions (upright and supine) regarding sex in the older age category.
Table 4.
Comparison of the FSTT in two head positions (upright and supine) regarding sex in the older age category.
| Females (N = 38) | Males (N = 18) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Anthropometric Landmark | Upright Position | Supine Position | Difference Between Positions 1 | p-Value | Upright Position | Supine Position | Difference Between Positions 1 | p-Value | ||||
| Mean | SD | Mean | SD | (mm) | Mean | SD | Mean | SD | (mm) | |||
| Metopion (mm) | 5.22 | 0.89 | 5.32 | 0.94 | −0.10 | >0.05 | 5.42 | 1.20 | 5.40 | 0.96 | 0.02 | >0.05 |
| Glabella (mm) | 5.77 | 0.92 | 5.36 | 0.78 | 0.41 | <0.001 * | 5.36 | 0.75 | 5.27 | 0.55 | 0.09 | >0.05 |
| Nasion (mm) | 4.90 | 0.83 | 4.60 | 0.84 | 0.30 | >0.05 | 4.20 | 0.90 | 4.11 | 0.70 | 0.09 | >0.05 |
| Rhinion (mm) | 3.51 | 0.82 | 3.66 | 0.91 | −0.15 | >0.05 | 3.62 | 0.81 | 3.51 | 1.13 | 0.11 | >0.05 |
| Midphiltrum (mm) | 8.36 | 2.21 | 7.83 | 2.60 | 0.53 | >0.05 | 10.51 | 2.22 | 10.13 | 1.39 | 0.38 | >0.05 |
| Supramentale (mm) | 10.59 | 1.25 | 10.17 | 1.49 | 0.42 | <0.05 * | 12.27 | 1.83 | 11.81 | 1.66 | 0.46 | >0.05 |
| Pogonion (mm) | 8.41 | 2.37 | 7.64 | 2.17 | 0.77 | <0.05 | 7.35 | 2.70 | 8.35 | 2.61 | −1.00 | >0.05 |
| Gnathion (mm) | 6.42 | 2.27 | 6.28 | 1.83 | 0.14 | >0.05 | 5.28 | 1.68 | 5.45 | 1.8 | −0.17 | >0.05 |
| Alare (mm) | 11.50 | 1.96 | 11.40 | 1.52 | 0.10 | >0.05 | 11.23 | 1.21 | 10.92 | 1.17 | 0.31 | >0.05 |
| Supraorbital (mm) | 6.11 | 2.16 | 6.57 | 2.63 | −0.46 | >0.05 | 5.40 | 1.41 | 5.39 | 1.49 | 0.01 | >0.05 |
| Infraorbital (mm) | 5.78 | 2.30 | 6.22 | 2.28 | −0.44 | >0.05 | 4.92 | 1.30 | 5.13 | 1.56 | −0.21 | >0.05 |
| Fossa canina (mm) | 18.71 | 2.56 | 17.75 | 2.59 | 0.96 | <0.05 * | 19.43 | 2.73 | 18.82 | 2.13 | 0.61 | >0.05 |
| Midmandible (mm) | 8.98 | 3.51 | 7.67 | 2.58 | 1.31 | <0.05 * | 7.53 | 2.82 | 6.91 | 1.99 | 0.62 | >0.05 |
| Malare (mm) | 10.98 | 1.64 | 10.93 | 1.15 | 0.05 | >0.05 | 10.92 | 0.93 | 10.79 | 0.79 | 0.13 | >0.05 |
| Zygomatic (mm) | 10.16 | 2.90 | 10.36 | 2.21 | −0.20 | >0.05 | 9.12 | 1.56 | 9.39 | 1.86 | −0.27 | >0.05 |
| Gonion (mm) | 7.59 | 3.29 | 7.67 | 3.57 | −0.08 | >0.05 | 5.11 | 1.22 | 6.91 | 3.13 | −1.80 | <0.001 * |
Abbreviations: N, total number of participants; p, statistical significance; SD, standard deviation. 1 The minus sign indicates higher average values in supine position; * marks statistical significance p < 0.05.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |
© 2025 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
MDPI and ACS Style
Kozáková, Z.; Sulis, S.; Falbová, D.; Vorobeľová, L.; Matláková, M.; Beňuš, R.; Švábová, P. Impact of Head Position on Facial Soft Tissue Thickness: An Ultrasound Study in the Slovak Population. Forensic Sci. 2025, 5, 5. https://doi.org/10.3390/forensicsci5010005
AMA Style
Kozáková Z, Sulis S, Falbová D, Vorobeľová L, Matláková M, Beňuš R, Švábová P. Impact of Head Position on Facial Soft Tissue Thickness: An Ultrasound Study in the Slovak Population. Forensic Sciences. 2025; 5(1):5. https://doi.org/10.3390/forensicsci5010005
Chicago/Turabian StyleKozáková, Zuzana, Simona Sulis, Darina Falbová, Lenka Vorobeľová, Mária Matláková, Radoslav Beňuš, and Petra Švábová. 2025. "Impact of Head Position on Facial Soft Tissue Thickness: An Ultrasound Study in the Slovak Population" Forensic Sciences 5, no. 1: 5. https://doi.org/10.3390/forensicsci5010005
APA StyleKozáková, Z., Sulis, S., Falbová, D., Vorobeľová, L., Matláková, M., Beňuš, R., & Švábová, P. (2025). Impact of Head Position on Facial Soft Tissue Thickness: An Ultrasound Study in the Slovak Population. Forensic Sciences, 5(1), 5. https://doi.org/10.3390/forensicsci5010005
