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![a, b Craniometric landmarks [nasion (n), rhinion (rhi), nasospinale (ns), alare (al) and prosthion (pro)] and planes on the nasal bone and periphery of the nasal aperture](publication/342829387/figure/fig3/AS:960123635789836@1605922721418/a-b-Craniometric-landmarks-nasion-n-rhinion-rhi-nasospinale-ns-alare-al-and.png)
a, b Craniometric landmarks [nasion (n), rhinion (rhi), nasospinale (ns), alare (al) and prosthion (pro)] and planes on the nasal bone and periphery of the nasal aperture
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The nose is the most prominent part of the face and is a crucial factor for facial esthetics as well as facial reconstruction. Although some studies have explored the features of external nose and predicted the relationships between skeletal structures and soft tissues in the nasal region, the reliability and applicability of methods used in previo...
Citations
... Studies show that combining CBCT to represent hard tissues and 3D photography for soft tissues is a reliable tool for studying some regions of the face. 10 However, it is necessary to generate standardized parameters for acquiring, processing, and analyzing 3D photographs. ...
... In this study, some authors agree that the facial expression should be neutral and relaxed, with the lips gently closed. 10,12,14,16,19,21,22,27,29,[31][32][33]38 However, no study refers to those individuals with forced lip closure, lip separation at rest, and lip incompetence. Due to the influence of expressions on facial measurements and the difficulty in defining the concept of "neutral facial expression," we consider this parameter to be the most inconsistent in standardizing the image. ...
... Baysal et al (2016) 48 and Dindaroğlu et al (2016) 49 reported that landmarks marked directly on the 3D facial file have higher reproducibility than those previously marked on the face. However, although most authors did not perform this premarking, using direct marking in the 3D files, 10,[13][14][15][16][17]19,21,[23][24][25][26][31][32][33][34][35]37,38,41 a large group of authors made the selection of points with a dermatograph pencil before making the images. 12,[27][28][29][30]36 Of all the articles analyzed, only Cassi et al (2018), 9 ...
Objective: Orthognathic surgery is a viable and reproducible treatment for facial deformities. Despite the precision of the skeletal planning of surgical procedures, there is little in- formation about the relations between hard and soft tissues in three-dimensional (3D) analysis, resulting in unpredictable soft tissue outcomes. Three-dimensional photography is a viable tool for soft tissue analysis because it is easy to use, has wide availability, low cost, and is harmless. This review aims to es- tablish parameters for acquiring consistent and reproducible 3D facial images.
Methods: A scoping review was conducted across PubMed, SCOPUS, Scientific Electronic Library Online (SciELO), and Web of Science databases, adhering to “Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews” guidelines. Articles presenting 3D facial photographs in the diagnostic phase were considered.
Results: A total of 79 articles were identified, of which 29 were selected for analysis.
Conclusion: The predominant use of automated systems like 3dMD and VECTRA M3 was noted. User positioning has highest agreement among authors. Noteworthy aspects include the importance of proper lighting, facial expression, and dental positioning, with observed discrepancies and inconsistencies among authors. Finally, the authors proposed a 3D image ac- quisition protocol based on this research findings.
... The estimated features on the left are from Stephan and Davidson (2008) for the placement of the eyes, and Rynn et al. (2010) for the nose, which are shown as blue lines on the left lateral view of the crania. Centre is Kim et al. (2016) for the eyes and Chu et al. (2020) for the nose, which are shown as green lines on the lateral crania. Each study's prediction of the start of the nasal tip is indicated by an open circle. ...
... This revision re-applies Rynn's algorithm to the Lapita remains but with a corrected identification of the subspinale (Caple and Stephan, 2015). A more recent approach devised by Chu et al. (2020) is also evaluated, using their equations to estimate nasal height, depth and location of the pronasale. Chu et al.'s regressions are derived from, and validated by, 240 medical CBCT scans and 3dMD photogrammetry taken from young adults living in north-western China. ...
... However, because the geometric morphometric analyses indicate that for both sexes the older individuals tend to have wider noses (refer Table 2), this width is likely acceptable for the Lapita remains. Chu et al. (2020) tend to locate the nasal base higher on the face and predict a narrower nose than the average of the men. This may be, however, due to the algorithmsas with Kim et al. (2016) being derived from young adults. ...
Although ancient DNA (aDNA) cannot predict the facial appearance of skeletal human remains, knowing which extant populations are most closely related to the deceased has proven to be invaluable in rectifying two early facial approximations (popularly known as facial reconstruction) undertaken 15 years ago. These concerned two of the crania excavated from the Lapita burial site at Teouma on the island of Efate, and are associated with the first human arrival in the Vanuatu archipelago approximately 3000 years ago. This experimental revision to incorporate aDNA into both the methods and results has found there are advantages of knowing the genetic affiliation for estimating facial appearance. Specifically, we have found that this knowledge (i) facilitates identifying which of the current statistically valid predictors of the facial features are the most appropriate, (ii) informs the depiction of sexually dimorphic patterns of facial aging, and (iii) guides the portrayal of the subtle facial morphologies that fall outside what is currently provided by statistically validated skull-soft tissue algorithms and inter-relationships.
... Digital Imaging and Communications in Medicine (DICOM) data from multislice CT images were reconstructed and analyzed using image-processing software Dolphin (version 11.8; Dolphin Imaging and Management Solutions, Chatsworth, CA, USA). Additionally, 3D stereophotogrammetry images were obtained using the 3dMDface system (3dMDface LLC, Atlanta, GA, USA), with a natural head position, relaxed facial expression, and eyes looking straight ahead 17 . The data of 3dMD was saved in the BMP format. ...
This study aimed to study 3-dimensional (3D) changes of hard and soft tissues of skeletal class II patients after 2-jaw surgery and genioplasty. 32 adult patients diagnosed with mandibular hypoplasia who underwent 2-jaw surgery of maxillary impaction, mandibular advancement and genioplasty were enrolled. Cone-beam computed tomography and 3D stereophotogrammetry was conducted 1 week before and 6 months after surgery. Dolphin imaging software was used to establish a 3D digitizing model and 3D measurement system. Paired t-test was performed to compare the values before and after surgery. Pearson’s correlation test assessed the degree of correlations between hard and soft tissue change. The mean impaction of the maxilla was 2.600 ± 3.088 mm at A. The mean advancement of the mandible was 7.806 ± 2.647 mm at B. There was a significant upward and forward movement for most landmarks of the nose and lip, while a significant decrease in nasal tip height (lateral view), upper lip height, and upper and lower vermilion height. The nose's width was significantly increased. For maxillary, Sn, Ac-r, Ac-l, and Ls demonstrated a significant correlation with A and U1 in the anteroposterior axis. However, there were no significant correlations among them in the vertical axis. For mandibular, Li demonstrated a significant correlation with L1 in the anteroposterior axis specifically for the mandible. Notably, correlations between the landmarks of the chin's hard and soft tissues were observed across all axes. The utilization of 3-D analysis facilitated a quantitative comprehension of both hard and soft tissues, thereby furnishing valuable insights for the strategic formulation of orthognathic treatment plans targeting patients with skeletal class II conditions.
... This technology allows the surgeon to quickly obtain and save the soft tissue morphology of the patient's face at any time of treatment, and to easily perform precise linear measurements and angular calculations of any marker point on the resulting 3D image of the face [222]. On this basis, in the wide range of applications it has received [101,210,[222][223][224], the patient's condition can be accurately analyzed and diagnosed before surgery and the surgical plan can be improved, and the soft tissue changes after orthognathic surgery can be accurately and efficiently evaluated and the efficacy demonstrated, providing key reference information for determining the success or failure of treatment. ...
Background
Three-dimensional(3D) reconstruction technology is a method of transforming real goals into mathematical models consistent with computer logic expressions and has been widely used in dentistry, but the lack of review and summary leads to confusion and misinterpretation of information. The purpose of this review is to provide the first comprehensive link and scientific analysis of 3D reconstruction technology and dentistry to bridge the information bias between these two disciplines.
Methods
The IEEE Xplore and PubMed databases were used for rigorous searches based on specific inclusion and exclusion criteria, supplemented by Google Academic as a complementary tool to retrieve all literature up to February 2023. We conducted a narrative review focusing on the empirical findings of the application of 3D reconstruction technology to dentistry.
Results
We classify the technologies applied to dentistry according to their principles and summarize the different characteristics of each category, as well as the different application scenarios determined by these characteristics of each technique. In addition, we indicate their development prospects and worthy research directions in the field of dentistry, from individual techniques to the overall discipline of 3D reconstruction technology, respectively.
Conclusions
Researchers and clinicians should make different decisions on the choice of 3D reconstruction technology based on different objectives. The main trend in the future development of 3D reconstruction technology is the joint application of technology.
... However, soft tissue extracted from CT in the supine position is affected by gravity; in addition, soft tissue from CBCT, might cause distortions due to the pressure of the chin cap. Currently, 3D facial photographs are obtained to analyze the soft tissue prior to the use of the other techniques due to the short capture time, comfortableness of the procedure and ability to produce highresolution color images [33]. In our study, we combined CBCT with 3dMD, a high-precision and noncontact 3D surface imaging technology with a 2 ms capture time, to digitally investigate the deviations of the hard and soft tissues simultaneously [34]. ...
Background
Facial symmetry severely affects appearance and function. Large numbers of patients seek orthodontic treatment to improve facial symmetry. However, the correlation between hard- and soft-tissue symmetry is still unclear. Our aim was to investigate the hard- and soft-tissue symmetry in subjects with different levels of menton deviation and sagittal skeletal classes with 3D digital analysis and to investigate the relationship between the entire and individual hard- and soft-tissues.
Methods
A total of 270 adults (135 males and 135 females) consisting of 45 subjects of each sex in each sagittal skeletal classification group. All subjects were further classified into relative symmetry (RS), moderate asymmetry (MA) and severe asymmetry (SA) groups based on the degree of menton deviation from the mid-sagittal plane (MSP). The 3D images were segmented into anatomical structures and mirrored across the MSP after establishing a coordinate system. Original and mirrored images were registered by a best-fit algorithm, and the corresponding root mean square (RMS) values and colormap were obtained. The Mann‒Whitney U test and Spearman correlation were conducted for statistical analysis.
Results
The RMS increased with greater deviations with regard to the deviation of the menton in most of anatomical structures. Asymmetry was represented in the same way regardless of sagittal skeletal pattern. The soft-tissue asymmetry had a significant correlation with dentition in the RS group (0.409), while in the SA group, it was related to the ramus (0.526) and corpus (0.417) in males and was related to the ramus in the MA (0.332) and SA (0.359) groups in females.
Conclusions
The mirroring method combining CBCT and 3dMD provides a new approach for symmetry analysis. Asymmetry might not be influenced by sagittal skeletal patterns. Soft-tissue asymmetry might be reduced by improving the dentition in individuals with RS group, while among those with MA or SA, whose menton deviation was larger than 2 mm, orthognathic treatment should be considered.
... facial photographs are obtained to analyze the soft tissue prior to the use of the other techniques due to the short capture time, comfortableness of the procedure and ability to produce high-resolution color images [33]. In our study, we combined CBCT with 3dMD, a high-precision and noncontact 3D surface imaging technology with a 2 ms capture time, to digitally investigate the deviations of the hard and soft tissues simultaneously [34]. ...
Background
Facial symmetry severely affects appearance and function. Large numbers of patients seek orthodontic treatment to improve facial symmetry. However, the correlation between hard- and soft-tissue symmetry is still unclear. Our aim was to investigate the hard- and soft-tissue symmetry in subjects with different levels of menton deviation and sagittal skeletal classes with 3D digital analysis and to investigate the relationship between the entire and individual hard- and soft-tissues.
Methods
A total of 270 adults (135 males and 135 females) consisting of 45 subjects of each sex in each sagittal skeletal classification group. All subjects were further classified into relative symmetry (RS), moderate asymmetry (MA) and severe asymmetry (SA) groups based on the degree of menton deviation from the mid-sagittal plane (MSP). The 3D images were segmented into anatomical structures and mirrored across the MSP. Original and mirrored images were registered by a best-fit algorithm, and the corresponding root mean square (RMS) values and colormap were obtained. The Mann‒Whitney U test and Spearman correlation were conducted for statistical analysis.
Results
The RMS increased with greater deviations with regard to the deviation of the menton in most of anatomical structures. Asymmetry was represented in the same way regardless of sagittal skeletal pattern. The soft-tissue asymmetry had a significant correlation with dentition in the RS group (0.409), while in the SA group, it was related to the ramus (0.526) and corpus (0.417) in males and was related to the ramus in the MA (0.332) and SA (0.359) groups in females.
Conclusions
The mirroring method combining CBCT and 3dMD provides a new approach for symmetry analysis. Asymmetry might not be influenced by sagittal skeletal patterns. Soft-tissue asymmetry might be reduced by improving the dentition in individuals with RS group, while among those with MA or SA, whose menton deviation was larger than 2 mm, orthognathic treatment should be considered.
... Over the past decades, many attempts have been made to examine sexual traits on radiological materials rather than real skeletal samples because of the increasing availability of human samples in clinical settings [11][12][13][14][15]. Radiological data can rectify the limitations of many reference collections from archaeological or historical populations by forming a modern skeletal assemblage, without the need for huge physical storage space and time-consuming, labor-intensive sample processing. ...
Deep learning based on radiological methods has attracted considerable attention in forensic anthropology because of its superior classification capacities over human experts. However, radiological instruments are limited in their nature of high cost and immobility. Here, we integrated a deep learning algorithm and three-dimensional (3D) surface scanning technique into a portable system for pelvic sex estimation. Briefly, the images of the ventral pubis (VP), dorsal pubis (DP), and greater sciatic notch (GSN) were cropped from virtual pelvic samples reconstructed from CT scans of 1000 individuals; 80% of them were used to train and internally evaluate convolutional neural networks (CNNs) that were then evaluated externally with the remaining samples. An additional 105 real pelvises were documented virtually with a handheld 3D surface scanner, and the corresponding snapshots of the VP, DP, and GSN were predicted by the trained CNN models. The CNN models achieved excellent performance in the external testing using CT-based images, with accuracies of 98.0%, 98.5%, and 94.0% for VP, DP, and GSN, respectively. When the CT-based models were applied to 3D scanning images, they obtained satisfactory accuracies above 95% on the VP and DP images compared to the GSN with 73.3%. In a single-blind trial, a multiple design that combined the three CNN models yielded a superior accuracy of 97.1% with 3D surface scanning images over two anthropologists. Our study demonstrates the great potential of deep learning and 3D surface scanning for rapid and accurate sex estimation of skeletal remains.
... Commonly used are 3DMD, Morpheus 3D, etc., and their precision and accuracy have been veri ed by previous studies [16][17][18][19]. Nevertheless, facial scanner can only record the morphology of soft tissues, which needs to be fused with CBCT when to explore the relationships and ratios of soft and hard tissues [20,21], thus possibly bringing the technical error when the two data fuse, which in turn affects the measurement results, and soft tissues imaged by CBCT avoid this problem [22]. ...
Background：Precise measurement of the morphological structure of soft and hard tissues is fundamental to the treatment of malocclusion, but the ability of cone beam CT(CBCT) for soft tissue measurements involves few studies to date. The purpose of this study was to assess the reliability of CBCT for nasolabial soft tissue measurements in patients with skeletal class III malocclusion based on 3-dimensional(3D) facial scanner results.
Methods：CBCT and 3D facial scan images of 20 orthognathic patients were used in this study. 11 soft tissue landmarks and 15 linear and angular measurements were identified and performed. For qualitative evaluation, Shapiro-Wilk Test and Bland-Altman plots were applied to analyze the equivalence of the measurements derived from these two kinds of data. To quantify specific deviation of CBCT measurements from facial scanner, the latter were set as a benchmark, and mean absolute difference(MAD) and relative error magnitude(REM) for each variable were calculated.
Results：Statistically significant differences were observed on length measurements of bilateral philtrum crests, width of mouth and angular measurements of the protrusion angle of lower lip, left angle of upper mouth and nasolabial angle between the two methods. The MAD value for all length measurements were less than 2 mm and for angular variables <8°. The average MAD and REM for length measurements was 0.94mm and 5.64% respectively, and 2.27°, 3.78% for angular measurements.
Conclusions：Certain inconformity exists in regions of nasal base and lower lip vermilion between CBCT and facial scanner when measuring nasolabial surfaces, but most of them are clinically acceptable. The soft tissue results measured by CBCT showed relatively good reliability and can be used for 3D measurement of soft tissue in the nasolabial region clinically.
... It provides a natural shape of the facial mask as the subject can be scanned in the seated [5] position . Several studies have employed CBCT scanning to analyze the relationship between the skeletal nasal bone and [6] external nose morphology in different populations . Zacharias fourie et-al,2010 conducted a study to assess accuracy and reliability of facial soft tissue depth measurements using CBCT. ...
... In forensic science, the estimation of external nose morphology may be a crucial issue that might help identify people supported skulls. to the present regard, the investigation of exter nal nose morphology supported CBCT and 3dMD images in living s u b j e c t s m a y p r o v i d e f u r t h e r h e l p t o f o re n s i c [6] anthropologists. most of the hard tissue measurement (nasal width, nasal height, nasal length, alare angle, nasal tip angle, rhinion protrusion, nTr-rhiTr, rhiTr-alTr, nTr-alTr, rhiTr-nsTr, and nTr-nsTr) were significantly different between males and females, apart from the nasal dorsum angle, nasolabial angle, nasospinale protrusion, and alTr-nsTr. ...
... However, in terms of Basis nasi angle, Nasal dorsum angle, Nasal tip angle, Nasolabial angle, and Basis nasi protrusion, no significant differences were observed between the sexes. In terms of sentimental tissues, [6] the males showed higher values compared to the females. ...
Background:Forensic facial reconstruction is a combination of both artistic skill and scientific methods.It can be used to reconstruct the soft tissues onto the skull in order to obtain the image of an individual for her/his recognition and identification . Some reviewers considered that forensic facial reconstruction is a method of facial approximation, i.e. various facial patterns can be established from the same skull. Main body: The review aimed to describe CBCT is the better investigating tool for the facial recognition for forensic identification A search in PubMed,Google Scholar,and Scopus electronic databases from 2010 to 2020 was conducted to include studies according to PRISMA guidelines.12 studies were eligible for the review. Conclusions: .Cone beam CT images of the face using routine scanning protocols are a reliable method of measuring the soft tissue thickness in the facial region and give a good representation of the facial soft tissues.
