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  1. Jayaprakash PT, Hashim N, Yusop RA
    Forensic Sci Int, 2015 Aug;253:131.e1-10.
    PMID: 26103927 DOI: 10.1016/j.forsciint.2015.04.026
    Video vision mixer based skull-photo superimposition is a popular method for identifying skulls retrieved from unidentified human remains. A report on the reliability of the superimposition method suggested increased failure rates of 17.3 to 32% to exclude and 15 to 20% to include skulls while using related and unrelated face photographs. Such raise in failures prompted an analysis of the methods employed for the research. The protocols adopted for assessing the reliability are seen to vary from those suggested by the practitioners in the field. The former include overlaying the skull- and face-images on the basis of morphology by relying on anthropometric landmarks on the front plane of the face-images and evaluating the goodness of match depending on mix-mode images; the latter consist of orienting the skull considering landmarks on both the eye and ear planes of the face- and skull-images and evaluating the match utilizing images seen in wipe-mode in addition to those in mix-mode. Superimposition of a skull with face-images of five living individuals in two sets of experiments, one following the procedure described for the research on reliability and the other applying the methods suggested by the practitioners has shown that overlaying the images on the basis of morphology depending on the landmarks on the front plane alone and assessing the match in mix-mode fails to exclude the skull. However, orienting the skull relying on the relationship between the anatomical landmarks on the skull- and face-images such as Whitnall's tubercle and exocanthus in the front (eye) plane and the porion and tragus in the rear (ear) plane as well as assessing the match using wipe-mode images enables excluding that skull while superimposing with the same set of face-images.
    Matched MeSH terms: Anatomic Landmarks*
  2. Jayaprakash PT
    Forensic Sci Int, 2017 Sep;278:411.e1-411.e8.
    PMID: 28754256 DOI: 10.1016/j.forsciint.2017.04.021
    Often cited reliability test on video superimposition method integrated scaling face-images in relation to skull-images, tragus-auditory meatus relationship in addition to exocanthion-Whitnall's tubercle relationship when orientating the skull-image and wipe mode imaging in addition to mix mode imaging when obtaining skull-face image overlay and evaluating the goodness of match. However, a report that found higher false positive matches in computer assisted superimposition method transited from the above foundational concepts and relied on images of unspecified sizes that are lesser than 'life-size', frontal plane landmarks in the skull- and face- images alone for orientating the skull-image and mix images alone for evaluating the goodness of match. Recently, arguing the use of 'life-size' images as 'archaic', the authors who tested the reliability in the computer assisted superimposition method have denied any method transition. This article describes that the use of images of unspecified sizes at lesser than 'life-size' eliminates the only possibility to quantify parameters during superimposition which alone enables dynamic skull orientation when overlaying a skull-image with a face-image in an anatomically acceptable orientation. The dynamic skull orientation process mandatorily requires aligning the tragus in the 2D face-image with the auditory meatus in the 3D skull-image for anatomically orientating the skull-image in relation to the posture in the face-image, a step not mentioned by the authors describing the computer assisted superimposition method. Furthermore, mere reliance on mix type images during image overlay eliminates the possibility to assess the relationship between the leading edges of the skull- and face-image outlines as also specific area match among the corresponding craniofacial organs during superimposition. Indicating the possibility of increased false positive matches as a consequence of the above method transitions, the need for testing the reliability in the superimposition method adopting concepts that are considered safe is stressed.
    Matched MeSH terms: Anatomic Landmarks*
  3. Abu A, Ngo CG, Abu-Hassan NIA, Othman SA
    BMC Bioinformatics, 2019 Feb 04;19(Suppl 13):548.
    PMID: 30717658 DOI: 10.1186/s12859-018-2548-9
    BACKGROUND: Indirect anthropometry (IA) is one of the craniofacial anthropometry methods to perform the measurements on the digital facial images. In order to get the linear measurements, a few definable points on the structures of individual facial images have to be plotted as landmark points. Currently, most anthropometric studies use landmark points that are manually plotted on a 3D facial image by the examiner. This method is time-consuming and leads to human biases, which will vary from intra-examiners to inter-examiners when involving large data sets. Biased judgment also leads to a wider gap in measurement error. Thus, this work aims to automate the process of landmarks detection to help in enhancing the accuracy of measurement. In this work, automated craniofacial landmarks (ACL) on a 3D facial image system was developed using geometry characteristics information to identify the nasion (n), pronasale (prn), subnasale (sn), alare (al), labiale superius (ls), stomion (sto), labiale inferius (li), and chelion (ch). These landmarks were detected on the 3D facial image in .obj file format. The IA was also performed by manually plotting the craniofacial landmarks using Mirror software. In both methods, once all landmarks were detected, the eight linear measurements were then extracted. Paired t-test was performed to check the validity of ACL (i) between the subjects and (ii) between the two methods, by comparing the linear measurements extracted from both ACL and AI. The tests were performed on 60 subjects (30 males and 30 females).

    RESULTS: The results on the validity of the ACL against IA between the subjects show accurate detection of n, sn, prn, sto, ls and li landmarks. The paired t-test showed that the seven linear measurements were statistically significant when p 

    Matched MeSH terms: Anatomic Landmarks*
  4. Nazri A, Agbolade O, Yaakob R, Ghani AA, Cheah YK
    BMC Bioinformatics, 2020 May 24;21(1):208.
    PMID: 32448182 DOI: 10.1186/s12859-020-3497-7
    BACKGROUND: Landmark-based approaches of two- or three-dimensional coordinates are the most widely used in geometric morphometrics (GM). As human face hosts the organs that act as the central interface for identification, more landmarks are needed to characterize biological shape variation. Because the use of few anatomical landmarks may not be sufficient for variability of some biological patterns and form, sliding semi-landmarks are required to quantify complex shape.

    RESULTS: This study investigates the effect of iterations in sliding semi-landmarks and their results on the predictive ability in GM analyses of soft-tissue in 3D human face. Principal Component Analysis (PCA) is used for feature selection and the gender are predicted using Linear Discriminant Analysis (LDA) to test the effect of each relaxation state. The results show that the classification accuracy is affected by the number of iterations but not in progressive pattern. Also, there is stability at 12 relaxation state with highest accuracy of 96.43% and an unchanging decline after the 12 relaxation state.

    CONCLUSIONS: The results indicate that there is a particular number of iteration or cycle where the sliding becomes optimally relaxed. This means the higher the number of iterations is not necessarily the higher the accuracy.

    Matched MeSH terms: Anatomic Landmarks*
  5. Hébert-Losier K, Abd Rahman F
    Physiother Theory Pract, 2018 Jun;34(6):483-494.
    PMID: 29281461 DOI: 10.1080/09593985.2017.1420117
    The Posture Pro software is used for photogrammetry assessment of posture and has been commercially available for several years. Along with symmetry-related measures, a Posture Number® is calculated to reflect the sum of postural deviations. Our aim was to investigate the intra- and inter-rater reliability of measures extracted using the Posture Pro 8 software without using reference markers on subjects. Four raters assessed the standing posture of 40 badminton players (20 males, 20 females) from anterior, lateral, and posterior photographs. Thirty-three postural measures were extracted using visual landmarks as guide. Reliability was quantified using intra-class correlation coefficient (ICC) and typical error of measurement (TEM). Overall, the intra-rater reliability was considered good to excellent for nearly all measures. However, only two measures had excellent inter-rater reliability, with 13 and 18 measures exhibiting good and fair inter-rater reliability, respectively. Posture Pro specific measures (n = 9) exhibited good-to-excellent intra-rater and fair-to-excellent inter-rater reliability, with small-to-moderate and small-to-large TEM, respectively. Overall, the Posture Pro 8 software can be considered a reliable tool for assessing a range of posture-relevant measures from photographs, particularly when performed by the same examiner. The Posture Number® demonstrated generally acceptable intra- and inter-rater reliability. Nonetheless, investigations on the validity, sensitivity, and interpretation of this measure are essential to confirm its clinical relevance.
    Matched MeSH terms: Anatomic Landmarks
  6. Yi KH, Kim SB, Hu H, An HS, Hidajat IJ, Lim TS, et al.
    Dermatol Surg, 2024 Sep 01;50(9):834-837.
    PMID: 38712848 DOI: 10.1097/DSS.0000000000004208
    BACKGROUND: Hypertrophied submandibular glands provide a bulky contour to the lower face. Botulinum neurotoxin injection methods are commonly used for facial contouring; however, no studies have suggested injection points because of the lack of delicate anatomical information on the submandibular gland.

    OBJECTIVE: The aim of this study was to determine the optimal injection site for botulinum neurotoxin injections in the submandibular gland.

    MATERIALS AND METHODS: Anatomical considerations when injecting botulinum neurotoxin into the submandibular gland were determined using ultrasonography. The thickness of the submandibular gland, its depth from the skin surface, and the location of the vascular bundle were observed bilaterally in 42 participants. Two cadavers were dissected to measure the location of the submandibular gland corresponding to the ultrasonographic observation.

    RESULTS: The thickest part of the submandibular gland measured 11.12 ± 2.46 in width with a depth of 4.63 ± 0.76. At the point where it crosses the line of the lateral canthus, it measured 5.53 ± 1.83 in width and 8.73 ± 1.64 in depth.

    CONCLUSION: The authors suggest optimal injection sites based on external anatomical landmarks. These guidelines aim to maximize the effects of botulinum neurotoxin therapy by minimizing its deleterious effects, which can be useful in clinical settings.

    Matched MeSH terms: Anatomic Landmarks
  7. Tan KL, Lee WH, Kim JW
    Eur Arch Otorhinolaryngol, 2017 Jan;274(1):223-229.
    PMID: 27423641 DOI: 10.1007/s00405-016-4201-4
    The skull base attachment of the second lamella and suprabullar pneumatization are likely to be consistent landmarks if they are systematically classified. This study aimed to classify the pneumatization pattern according to the second lamella skull base attachment. A total of 202 computed tomography sides of 101 patients who underwent endoscopic sinus surgery were studied. Suprabullar pneumatization was defined as air cells present above the ethmoid bulla between the second and third lamellae. Its pattern was classified according to the air cell number and location as in the frontal cell classification. Type 0 suprabullar pneumatization was defined as no air cells between the ethmoid bulla and skull base; type 1, as a single suprabullar cell; and type 2, as multiple suprabullar cells above the ethmoid bulla. In type 3 pneumatization, the second lamella extended into the frontal sinus forming a frontal bullar cell. Type 2 was the most prevalent (40.1 %), followed by types 1, 3, and 0 (24.3, 23.3, and 12.4 %, respectively). The distance between the second lamella and anterior ethmoid artery was 8.93, 8.30, 8.50, and 11.25 mm in types 0, 1, 2, and 3 pneumatization, respectively. No patients had intraoperative injuries in the anterior ethmoid artery or lateral lamella. The second lamella skull base attachment and suprabullar pneumatization pattern could be systematically classified and be a consistent landmark to identify the frontal sinus opening.
    Matched MeSH terms: Anatomic Landmarks*
  8. Othman SA, Ahmad R, Asi SM, Ismail NH, Rahman ZA
    Br J Oral Maxillofac Surg, 2014 Mar;52(3):208-13.
    PMID: 24342372 DOI: 10.1016/j.bjoms.2013.11.008
    The aims of this study were to assess the quantitative values of measurements using proportion indices in the craniofacial region in patients with repaired, non-syndromic, complete unilateral cleft lip and palate (UCLP), and compare them with a control group who did not have clefts using the non-invasive systems of 3-dimensional technology. Three-dimensional measurements of the facial surfaces of 15 Malay patients who had UCLP repaired and 100 Malay control patients aged 18-25 years were analysed. The 3-dimensional images of the respondents' faces were captured using the VECTRA-3D Stereophotogrammetry System. Eleven craniofacial proportions were assessed using a combination of 18 linear measurements obtained from 21 anthropometric soft tissue landmarks. These measurements were used to produce proportion indices to find the differences in the morphological features between the groups, and assessed using the independent sample t test and z scores. There were significant differences between the groups in 7 out of 11 craniofacial proportion indices (p=0.001-0.044). Z scores of 2 indices were disproportionate. They were nasal index (which was severely supernormal) and upper lip index (which was moderately supernormal). Patients with UCLP had higher mean z scores, indicating that patients with UCLP tended to have larger faces than the control group. There were clinically important differences mainly in the nasolabial area, where the nose and the upper lip were wider, larger, or flatter in patients with UCLP.
    Matched MeSH terms: Anatomic Landmarks/pathology
  9. Othman SA, Ahmad R, Mericant AF, Jamaludin M
    Aust Orthod J, 2013 May;29(1):58-65.
    PMID: 23785939
    Fast and non-invasive systems of the three-dimensional (3D) technology are a recent trend in orthodontics. The reproducibility of facial landmarks is important so that 3D facial measurements are accurate and may-be applied clinically. The aim of this study is to evaluate the reproducibility of facial soft tissue landmarks using a non-invasive stereo-photogrammetry 3D camera.
    Matched MeSH terms: Anatomic Landmarks/anatomy & histology*
  10. Voon YS, Patil PG
    J Prosthet Dent, 2018 Apr;119(4):568-573.
    PMID: 28838820 DOI: 10.1016/j.prosdent.2017.05.011
    STATEMENT OF PROBLEM: The genial tubercle is a clinically palpable landmark in the mandible and can be identified in cone beam computed tomography (CBCT). Its location can be used to measure the safe zone in the interforaminal region of the mandible. These measurements may be helpful for implant treatment planning in patients with complete edentulism.

    PURPOSE: The purpose of this clinical study was to evaluate the safe distance in the interforaminal region of the mandible measured from the genial tubercle level for implant osteotomy in a Chinese-Malaysian population.

    MATERIAL AND METHODS: A total of 201 Digital Imaging and Communications in Medicine (DICOM) files were selected for the study from the CBCTs of dentate or edentulous Chinese-Malaysian adult patients with ongoing or completed treatments. Measurements were made with implant planning software. The anatomy of the whole mandible was assessed in the coronal cross-sectional, horizontal view and in panoramic view. Measurements were obtained in millimeters on one side by locating and marking a genial tubercle and then marking the mesial margin of the mental foramen and the anterior loop of the inferior alveolar nerve. The corresponding points of these landmarks were identified on the crest of the mandibular ridge to measure the linear distances. All the measurement steps were repeated on the other side. The linear distance of 2 mm was deducted from the total distance between the genial tubercle and the anterior loop separately for left and right side measurements to identify the safe zone. The mixed 2-way analysis of variance (ANOVA) test was used to analyze side and sex-related variations.

    RESULTS: The mean safe zone measured at the crestal level from the genial tubercle site on the left side of the mandible was 21.12 mm and 21.67 mm on the right side. A statistically significant (P

    Matched MeSH terms: Anatomic Landmarks*
  11. Al-Amery SM, Nambiar P, Jamaludin M, John J, Ngeow WC
    PLoS One, 2015;10(2):e0117251.
    PMID: 25679505 DOI: 10.1371/journal.pone.0117251
    The maxillary incisive canal connects the roof of the oral cavity with the floor of nasal cavity and has the incisive and nasal foramina respectively at its two opposite ends. Its close proximity with the anterior incisors affects one's ability to place immediate implants in ideal position.
    Matched MeSH terms: Anatomic Landmarks
  12. Fareen N, Alam MK, Khamis MF, Mokhtar N
    Orthod Craniofac Res, 2017 Aug;20(3):134-139.
    PMID: 28440029 DOI: 10.1111/ocr.12179
    OBJECTIVE: Reverse Twin-Block (RTB) and Reverse Pull Face Mask (RPFM) appliances are used to correct Class III malocclusion in growing patients. Aim of this retrospective study was to compare and analyse craniofacial changes produced by RTB and RPFM in the early and late mixed dentition in Malay children with Class III malocclusion.

    METHODS: Data consisted of pre- and post-treatment lateral cephalograms of 95 children, 49 patients with RTB and 46 patients with RPFM, divided into an early (8-9 year) and late (10-11 year) group. Treatment changes were assessed by the Ricketts analysis using CASSOS software, where 71 anatomic landmarks were identified in each cephalogram. Paired and independent t tests were performed for statistical comparison.

    RESULTS: Paired t test revealed significant changes in facial axis, facial angle, MD plane to FH, lower facial height, mandibular arc, maxillary convexity, U1 to APog, L1 to APog, L1 to APog angle and upper lip to E-plane measurements in RPFM, whereas significant changes were found in facial taper, U1 to APog and lower lip to E-plane values with RTB in the early treatment group. Independent t test revealed significant changes in U1 to APog, L1 to APog and U6 to PtV values in the RTB group. Post-treatment comparison of RTB and RPFM showed significant differences in L1 to APog and L1 to APog angle values.

    CONCLUSIONS: RPFM revealed more favourable craniofacial changes than RTB, particularly in the late mixed dentition stage.

    Matched MeSH terms: Anatomic Landmarks
  13. Agbolade O, Nazri A, Yaakob R, Ghani AA, Cheah YK
    PLoS One, 2020;15(4):e0228402.
    PMID: 32271782 DOI: 10.1371/journal.pone.0228402
    BACKGROUND: The application of three-dimensional scan models offers a useful resource for studying craniofacial variation. The complex mathematical analysis for facial point acquisition in three-dimensional models has made many craniofacial assessments laborious.

    METHOD: This study investigates three-dimensional (3D) soft-tissue craniofacial variation, with relation to ethnicity, sex and age variables in British and Irish white Europeans. This utilizes a geometric morphometric approach on a subsampled dataset comprising 292 scans, taken from a Liverpool-York Head Model database. Shape variation and analysis of each variable are tested using 20 anchor anatomical landmarks and 480 sliding semi-landmarks.

    RESULTS: Significant ethnicity, sex, and age differences are observed for measurement covering major aspects of the craniofacial shape. The ethnicity shows subtle significant differences compared to sex and age; even though it presents the lowest classification accuracy. The magnitude of dimorphism in sex is revealed in the facial, nasal and crania measurement. Significant shape differences are also seen at each age group, with some distinct dimorphic features present in the age groups.

    CONCLUSIONS: The patterns of shape variation show that white British individuals have a more rounded head shape, whereas white Irish individuals have a narrower head shape. White British persons also demonstrate higher classification accuracy. Regarding sex patterns, males are relatively larger than females, especially in the mouth and nasal regions. Females presented with higher classification accuracy than males. The differences in the chin, mouth, nose, crania, and forehead emerge from different growth rates between the groups. Classification accuracy is best for children and senior adult age groups.

    Matched MeSH terms: Anatomic Landmarks
  14. Zreaqat M, Hassan R, Halim AS
    Int J Oral Maxillofac Surg, 2012 Jun;41(6):783-8.
    PMID: 22424709 DOI: 10.1016/j.ijom.2012.02.003
    This comparative cross-sectional study assessed the facial surface dimensions of a group of Malay children with unilateral cleft lip and palate (UCLP) and compared them with a control group. 30 Malay children with UCLP aged 8-10 years and 30 unaffected age-matched children were voluntarily recruited from the Orthodontic Specialist Clinic in Hospital Universiti Sains Malaysia (HUSM). For the cleft group, lip and palate were repaired and assessment was performed prior to alveolar bone grafting and orthodontic treatment. The investigation was carried out using 3D digital stereophotogrammetry. 23 variables and two ratios were compared three-dimensionally between both groups. Statistically significant dimensional differences (P<0.05) were found between the UCLP Malay group and the control group mainly in the nasolabial region. These include increased alar base and alar base root width, shorter upper lip length, and increased nose base/mouth width ratio in the UCLP group. There were significant differences between the facial surface morphology of UCLP Malay children and control subjects. Particular surgical procedures performed during primary surgeries may contribute to these differences and negatively affect the surgical outcome.
    Matched MeSH terms: Anatomic Landmarks/pathology
  15. Lim MY, Lim WW, Rajan S, Nambiar P, Ngeow WC
    Eur Arch Paediatr Dent, 2015 Oct;16(5):397-407.
    PMID: 25894248 DOI: 10.1007/s40368-015-0184-x
    To observe age-related changes in the locations of mandibular foramen (MF) and mental foramen (mf) using dental panoramic tomographs (DPTs).
    Matched MeSH terms: Anatomic Landmarks/radiography
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