Nose profile morphology and accuracy study of nose profile estimation method in Scottish subadult and Indonesian adult populations.

This study investigated nose profile morphology and its relationship to the skull in Scottish subadult and Indonesian adult populations, with the aim of improving the accuracy of forensic craniofacial reconstruction. Samples of 86 lateral head cephalograms from Dundee Dental School (mean age, 11.8 years) and 335 lateral head cephalograms from the Universitas Padjadjaran Dental Hospital, Bandung, Indonesia (mean age 24.2 years), were measured. The method of nose profile estimation based on skull morphology previously proposed by Rynn and colleagues in 2010 (FSMP 6:20-34) was tested in this study. Following this method, three nasal aperture-related craniometrics and six nose profile dimensions were measured from the cephalograms. To assess the accuracy of the method, six nose profile dimensions were estimated from the three craniometric parameters using the published method and then compared to the actual nose profile dimensions.In the Scottish subadult population, no sexual dimorphism was evident in the measured dimensions. In contrast, sexual dimorphism of the Indonesian adult population was evident in all craniometric and nose profile dimensions; notably, males exhibited statistically significant larger values than females. The published method by Rynn and colleagues (FSMP 6:20-34, 2010) performed better in the Scottish subadult population (mean difference of maximum, 2.35 mm) compared to the Indonesian adult population (mean difference of maximum, 5.42 mm in males and 4.89 mm in females).In addition, regression formulae were derived to estimate nose profile dimensions based on the craniometric measurements for the Indonesian adult population. The published method is not sufficiently accurate for use on the Indonesian population, so the derived method should be used. The accuracy of the published method by Rynn and colleagues (FSMP 6:20-34, 2010) was sufficiently reliable to be applied in Scottish subadult population.

Discriminant analysis of mandibular measurements for the estimation of sex in a modern Brazilian sample.

The present study aimed to evaluate the accuracy of mandibular measurements for sex determination in a Brazilian population. The sample was composed of 100 mandibles, of which 53 were female and 47 were male, and the average age was 57.03 years. The mandible measurement protocol was composed of 15 measurements, of which six were bilateral and nine were unique. Mandibles were directly measured using a digital caliper and a protractor. The descriptive analysis of the present study revealed higher mean values for male mandibles compared to those for female mandibles with the exception of the left mandibular angle. Among the 21 measures analyzed in this group, 15 were statistically significant (p < 0.05). Univariate discriminant analyses produced a mean percentage of correct predictions that varied between 49 and 79%. The association of variables increased the percentage of correct prediction of sex to vary from 76 to 86%. The receiver operator characteristic (ROC) curve analysis indicated that the best variable for estimating sex was bigonial breadth (BGB; area under the ROC curve (AUC) = 0.764) followed by the right maximum ramus height (MRHr; AUC = 0.763). A reference table for estimating sex in a Brazilian population using mandible measurements was developed based on the ROC curve analysis. Mandibular measures provide a simple and reliable method for sex discrimination in Brazilian adults due to the sexual dimorphism revealed by analysis of the metric variables and the satisfactory results demonstrated by discriminant formulas, ROC curve analysis, and the reference table.

A revised nose tip shape validation method for facial reconstruction based on CT data from a modern German population.

Several methods aid with reconstructing features of the human nose, including angle, projection and width, but only one study by Davy-Jow et al. (2012) has focused on nose tip shape. The main finding was that the shape of the nasal bridge is consistent with the shape of the nose tip. The study also theorised that the method would not be suitable for snub (upturned) noses. Although promising, further investigation with a larger sample of different origin would be of benefit. In addition, grouping samples into upturned, horizontal and downturned nose tips could reveal the need for a difference in the applied method. The approach has been recreated with a larger sample size (N = 103 versus N = 25) derived from a modern German population. Based on soft tissue models, the individuals were firstly grouped into three categories; upturned, horizontal, and downturned noses. Computed Tomography (CT) data allowed the simultaneous visualisation of both skull and (semi-transparent) facial surfaces. Each head was viewed frontally in the Frankfurt Horizontal Plane (FHP), and then tilted back until the nasal tip superimposed the nasal bridge, with the angle of tilt measured from the FHP. The results show that the angle of tilt is significantly different for upturned, horizontal, and downturned noses, but that it can be equally applied to all three groups. The mean angle was 44° for upturned noses, 51° for horizontal, and 56° for downturned. Error studies suggest a very high accuracy and repeatability with intra-class correlation coefficients of 0.991 (inter-observer error) and 0.972 (intra-observer error) respectively.

Prediction of nasal morphology from the skull.

The objective of this study was to compose a reliable and readily reproducible method of predicting nasal morphology from the bony aperture, which restricts subjectivity whilst allowing anatomical nuance to be taken into account. Clinical head CT data from a sample of 79 North American subjects of varied ancestry was analysed for interrelationships between the bone and soft tissue of the nose in three dimensions, then pooled with 60 lateral cephalograms of subjects of European ancestry from England to augment nasal profile data. A series of simple regression equations was produced using linear distances between pairs of bony landmarks to predict nasal profile dimensions and restrict potential subjective error in Gerasimov's "Two-tangent" method. Maximum nasal width, the position of the alae and nostrils, and prediction of nasal asymmetry were incorporated into the resulting threedimensional nasal prediction method.

Estimation of the mandibular dimensions from linear cranial measurements for use in craniofacial reconstruction: A preliminary study.

BACKGROUND: A missing mandible is a common problem in facial identification cases requiring forensic facial approximation or reconstruction. The Sassouni and Sassouni-Plus methods which are currently used to predict the missing mandible from the cranium produce low levels of accuracy. AIMS: This study proposes a new method for the estimation of the overall dimensions of the mandible based upon linear cranial measurements, the proposed method has the potential to be utilised in the facial reconstruction of a range of adult skulls with dentition. SAMPLE AND METHOD: 21 measurements were taken from a sample of 90 skulls, 44 male, 43 female and three juvenile, originating from 9 different geographical areas. Ordinary least-squares regression, hierarchical cluster analysis and analysis of variance (ANOVA) were used to investigate trends in the data and to produce equations for the estimation of condylar height, corpus length and anterior height. CONCLUSION: When tested the equations produced an overall mean error of 0.09 mm with a standard deviation of ±4.84. The proposed method offers an improvement upon the currently used methods. It can be used to estimate the overall mandibular dimensions with a good level of accuracy.

Facial average soft tissue depth variation based on skeletal classes in Indonesian adult population: A retrospective lateral cephalometric study.

OBJECTIVE: To understand the influence of three types of skeletal classes (Class I, Class II and Class III) on midline average soft tissue depth (ASTD). METHODS: Lateral cephalograms of 335 pre-treatment orthodontic patients were obtained from the archive of Radiology Clinic Universitas Padjadjaran Dental Hospital Bandung Indonesia. The linear measurements of 10 midline facial landmarks ASTD and angular measurement of ANB were extracted and analysed statistically. RESULTS: A database of ASTD grouped by skeletal classes, specific for the Indonesian population, within the South East Asian ancestry group was obtained. CONCLUSIONS: A generic pattern of deeper upper lip than lower lip in class III compared to class II and conversely, deeper lower lip than upper lip in class II compared to class III, was visible in both male and female groups.

Craniofacial reconstruction of the Indus Valley Civilization individuals found at 4500-year-old Rakhigarhi cemetery.

Despite academic efforts to study the Indus Valley Civilization (IVC), there have as yet been no successful attempts to unveil the IVC people's craniofacial appearance. We investigated the IVC cemetery area of Rakhigarhi site, which was estimated to be of 2273 ± 38 and 2616 ± 73 years BCE. By craniofacial reconstruction (CFR) procedure using computed tomography (CT) data of two Rakhigarhi skulls (A1 BR02 and A2 BR36), we successfully reconstructed the faces of the IVC individuals who were buried about 4500 years ago. This is the first attempt to unveil scientifically accurate representations of IVC people's actual facial morphology.

Sexing the Cranium from the Foramen Magnum Using Discriminant Analysis in a Brazilian Sample.

In the identification process, the foramen magnum has shown controversial results in sex estimation. The present study aimed to analyze the morphometric variables of the foramen magnum in Brazilian adult cranium for sex estimation. The sample was composed of 100 craniums (53 males and 47 females) from the documented collection of the Institute of Teaching and Research in Forensic Sciences. The protocol measurement was constituted of two linear measurements: maximum length of the foramen magnum and maximum breadth of the foramen magnum and two formulas to calculate the area, method one (M1) and method two (M2). Descriptive statistics showed statistically significant differences between sex (p<0.05) for all variables. The univariate discriminant functions showed an accuracy between 56.0-62.0%, and the multivariate analysis showed a percentage of accuracy between 60.0-65.0%, the greatest accuracy was found combining the two linear measurements with M1(71.7%), even after cross-validation (66%). Receiver Operating Characteristic (ROC) curve analysis showed that M2 is the best parameter for estimating sex (AUC=0.693). A reference table for Brazilians using the foramen magnum parameters was developed based on the results of the ROC curve analysis. In conclusion, the foramen magnum should be used with caution to estimate sex in forensic cases of fragmentary craniums, due to the limited accuracy.

Sexing the cranium from the foramen magnum using discriminant analysis in a brazilian sample

Abstract In the identification process, the foramen magnum has shown controversial results in sex estimation. The present study aimed to analyze the morphometric variables of the foramen magnum in Brazilian adult cranium for sex estimation. The sample was composed of 100 craniums (53 males and 47 females) from the documented collection of the Institute of Teaching and Research in Forensic Sciences. The protocol measurement was constituted of two linear measurements: maximum length of the foramen magnum and maximum breadth of the foramen magnum and two formulas to calculate the area, method one (M1) and method two (M2). Descriptive statistics showed statistically significant differences between sex (p<0.05) for all variables. The univariate discriminant functions showed an accuracy between 56.0-62.0%, and the multivariate analysis showed a percentage of accuracy between 60.0-65.0%, the greatest accuracy was found combining the two linear measurements with M1(71.7%), even after cross-validation (66%). Receiver Operating Characteristic (ROC) curve analysis showed that M2 is the best parameter for estimating sex (AUC=0.693). A reference table for Brazilians using the foramen magnum parameters was developed based on the results of the ROC curve analysis. In conclusion, the foramen magnum should be used with caution to estimate sex in forensic cases of fragmentary craniums, due to the limited accuracy.

Resumo No processo de identificação humana, a análise do forame magno apresenta resultados controversos para estimativa do sexo. O presente estudo teve como objetivo analisar as variáveis morfométricas do forame magno em crânios adultos brasileiros para estimação sexual. A amostra foi composta por 100 crânios (53 sexos masculino e 47 sexo feminino) pertencentes a coleção osteológica documentada do Instituto de Ensino e Pesquisa em Ciências Forenses. A medida do protocolo foi constituída por duas medidas lineares: comprimento máximo do forame magno e largura máxima do forame magno e duas fórmulas para calcular a área, método um (M1) e método dois (M2). As estatísticas descritivas evidenciaram diferenças estatisticamente significativas (p<0,05) para todas as variáveis. As funções discriminantes univariadas apresentaram uma porcentagem de acerto entre 56,0-62,0% e a análise multivariada mostrou uma porcentagem de acerto entre 60,0-65,0%. A análise da curva ROC apontou que M2 é o melhor parâmetro para estimar o sexo (AUC=0,693). Uma tabela de referência para brasileiros que utilizam os parâmetros do forame magnum foi desenvolvida com base nos resultados da análise da curva ROC. Em conclusão, o foram e magnum deve ser usado com precaução para estimar o sexo em casos forenses de cranio fragmentado, devido à precisão limitada.

Craniometric variation among Brazilian and Scottish populations: a physical anthropology approach

Aim: The present investigation intended to compare the craniometric variations of two samples of different nationalities (Brazilian and Scottish). Materials and methods: The Brazilian sample consisted of 100 modern complete skulls, including 53 female skulls and 47 male skulls, and the Scottish sample consisted of 100 historical skulls (61 males, 39 females) and 36 mandibles (24 males, 12 females). The cranial measurement protocol was composed of 40 measurements, 11 bilateral and 29 unilateral, and the measurement protocol of the mandible was composed of 15 measurements, with six that were bilateral and nine that were unique. The comparative analysis of the metric variability between the two samples was performed using the means and medians analysis, the t-test, the Wilcoxon test, and the coefficient of variance, with a significance level of 5%. Results: The results showed that, among the 72 analysed variables, 44 measurements (61.11%) presented statistical differences between the samples. The Scottish skull tends to have a cranial length (GOL diff=5.53), breadth (XCB diff=3.78) and height (NPH diff=5.33) greater than the Brazilian skulls, and the Scottish mandibles tend to show a higher mandibular ramus height (MRH diff=9.25), a higher mandibular body height (HMB diff=6.37) and a larger bigonial breadth (BGB diff=5.29) than the Brazilians. The discriminant analysis of the 51 cranial measurements and 21 mandibular measurements showed a variation of the percentage of accuracy between 46.3-83.8%. Conclusion: The metric analysis demonstrated that there is variability between the two samples studied (61,11%), but a concrete cause cannot be determined considering the multifactorial aspects of the variations of form and size

Appraisal of traditional and recently proposed relationships between the hard and soft dimensions of the nose in profile.

This paper tests six methods of predicting external nasal profile proportions, using the form and dimensions of the bony nasal (piriform) aperture. A sample of 122 lateral cephalograms was measured and traced before each method was attempted, under blind conditions where appropriate. Error was assessed by comparing predicted to actual proportions. Methods used by the following authors were tested: Krogman and Iscan (1986 The Human Skeleton in Forensic Medicine, Springfield: C.C. Thomas), Gerasimov (1955 The Reconstruction of the Face on the Skull), Prokopec and Ubelaker (2002 Forensic Sci. Commun. 4:1-4), Macho (1986 J. Forensic Sci. 31:1391-1403), George (1987 J. Forensic Sci. 32:1305-1330), and Stephan et al. (2003 Am J. Phys. Anthropol. 122:240-250). The two-tangent method by Gerasimov (1955 The Reconstruction of the Face on the Skull) was found to perform best at predicting a point on the nasal tip on male and female preoperative subjects. The method of Krogman and Iscan (1986 The Human Skeleton in Forensic Medicine, Springfield: C.C. Thomas) performed poorly, as did the nasal profile determination method (Prokopec and Ubelaker 2002 Forensic Sci. Commun. 4:1-4). The other methods, all derived by a process of regression calculations, were shown to perform with variable accuracy on this sample, despite the age range and ethnicity of this sample closely resembling that of the samples from which these methods were derived.