The application of Kvaal's dental age calculation technique on panoramic dental radiographs

INTRODUCTION: Literature reports on a method for dental age calculation which is based only on radiological measurements on periapical dental radiographs: the relationship between chronological age and the two-dimensional dental pulpal size was analysed by means of multiple regression analyses. The purpose of the present study was to evaluate whether this approach could be feasible and could lead to statistically sound results with adequate repeatability when applied on panoramic radiographs. MATERIALS AND METHODS: One hundred and ninety seven panoramic radiographs were collected at random from patients of whom the age ranged from 19 to 75 years. According to the reported technique, six teeth were selected on the panoramic radiograph: in the maxilla the central and lateral incisor and second bicuspid, and in the mandibula the lateral incisor, cuspid and first bicuspid. The same exclusion criteria as in the original paper were respected. Statistical analysis was carried out in order to spot significant differences between the chronological age and the calculated age. RESULTS: When the age was calculated based on measurements of all six teeth or of all three mandibular teeth, no significant differences were found between the real age and the calculated one. In all other instances using the individual teeth separately or using all three maxillary teeth statistical analysis revealed significant differences. CONCLUSION: There appears to be no significant difference between applying the original technique on standard long-cone periapical radiographs or on orthopantomograms, especially when carrying out measurements on all six selected teeth.     

Large-scale in-vivo Caucasian facial soft tissue thickness database for craniofacial reconstruction

A large-scale study of facial soft tissue depths of Caucasian adults was conducted. Over a 2-years period, 967 Caucasian subjects of both sexes, varying age and varying body mass index (BMI) were studied. A user-friendly and mobile ultrasound-based system was used to measure, in about 20min per subject, the soft tissue thickness at 52 facial landmarks including most of the landmarks used in previous studies. This system was previously validated on repeatability and accuracy [S. De Greef, P. Claes, W. Mollemans, M. Loubele, D. Vandermeulen, P. Suetens, G. Willems, Semi-automated ultrasound facial soft tissue depth registration: method and validation. J. Forensic Sci. 50 (2005)]. The data of 510 women and 457 men were analyzed in order to update facial soft tissue depth charts of the contemporary Caucasian adult. Tables with the average thickness values for each landmark as well as the standard deviation and range, tabulated according to gender, age and BMI are reported. In addition, for each landmark and for both sexes separately, a multiple linear regression of thickness versus age and BMI is calculated. The lateral asymmetry of the face was analysed on an initial subset of 588 subjects showing negligible differences and thus warranting the unilateral measurements of the remaining subjects. The new dataset was statistically compared to three datasets for the Caucasian adults: the traditional datasets of Rhine and Moore [J.S. Rhine, C.E. Moore, Tables of facial tissue thickness of American Caucasoids in forensic anthropology. Maxwell Museum Technical series 1 (1984)] and Helmer [R. Helmer, Sch?delidentifizierung durch elektronische bildmischung, Kriminalistik Verlag GmbH, Heidelberg, 1984] together with the most recent in vivo study by Manhein et al. [M.H. Manhein, G.A. Listi, R.E. Barsley, R. Musselman, N.E. Barrow, D.H. Ubelbaker, In vivo facial tissue depth measurements for children and adults. J. Forensic Sci. 45 (2000) 48-60]. The large-scale database presented in this paper offers a denser sampling of the facial soft tissue depths of a more representative subset of the actual Caucasian population over the different age and body posture subcategories. This database can be used as an updated chart for manual and computer-based craniofacial approximation and allows more refined analyses of the possible factors affecting facial soft tissue depth.     

Dental age estimation in Belgian children: Demirjian's technique revisited.

Aim: The purpose of this study was to evaluate the accuracy of Demirjian's dental age estimation in children in a Belgian Caucasian population and to adapt the scoring system in case of a significant overestimation as frequently reported. We selected 2523 orthopantomograms of 1265 boys and 1258 girls, of which 2116 (1029 boys and 1087 girls) were used for estimating the dental age with the Demirjian's technique. The 407 other orthopantomograms were beyond the original age limit. A second sample of 355 orthopantomograms was used to evaluate the accuracy of the original method and the adapted method. A signed-rank test was performed to search for significant age differences between the obtained dental age and the chronological age. A weighted ANOVA was performed in order to adapt the scoring system for this Belgian population. The overestimation of the chronological age was confirmed. The adapted scoring system resulted in new age scores expressed in years and in a higher accuracy compared to the original method in Belgian Caucasians.     

Estimating Age of Majority on Third Molars Developmental Stages in Young Adults from Thailand Using a Modified Scoring Technique*

Abstract: The aim of this study was to achieve a referral database for dental age estimation of unaccompanied minors of Thai nationality. A total of 1199 orthopantomograms were collected from original Thai women and men equally divided in age categories between 15 and 24 years. On the radiographs, the developmental stage of the third molars was scored applying a modified scoring technique. Inter- and intra-observer reliabilities were tested using kappa statistics. Correlation between the scores of all four wisdom teeth and left–right symmetry were evaluated with Pearson’s correlation coefficient. Student’s t-test on asymmetry was performed and regression formulas were calculated. The present database was the first to assemble third molar developmental scores on radiographs of Thai individuals and provides more appropriate dental age estimation of unaccompanied Thai minors. Future research on similar databases of different nationalities worldwide may expose ethnical influences on dental development.     

Is breast best? Evaluating breastfeeding patterns and causes of infant death in a Dutch province in the period 1875–1900

In the Dutch province of Noord-Brabant, infants experienced extremely high mortality risks towards the final decades of the nineteenth century. It has been stated that infant survival in the past highly depended upon the fact whether a child was breastfed or not. In this article we will reflect on this perceived importance of infant diet in order to explain the high mortality risks of Brabant infants in the period 1875–1900. Using local aggregated cause of death data, a change in breastfeeding practices can indeed be detected. Between 1875/79 and 1895/99 there was an increase in the relative and absolute number of infants deaths as a result of diarrhoea and other digestive disorders indicating deficient hygiene and that fewer infants were breastfed frequently. By discussing differences between urban and rural settings, and between Catholic and Protestant regions, we will shed more light on possible mechanisms for this change in breastfeeding practices.     

Non-destructive dental-age calculation methods in adults: intra- and inter-observer effects

The aim of the present study was to obtain data on the reliability and reproducibility of two non-destructive dental-age estimation methods in adults by calculating inter- and intra-observer effects. Both a morphological and a radiological technique available in the scientific literature were evaluated on a number of recently extracted teeth: the morphological technique was evaluated on a total of 160 teeth by two examiners, while three examiners applied the radiological technique on apical radiographs of 72 extracted teeth. Paired t-tests were used to calculate intra- and inter-observer differences. For the morphological method, both examiners were able to produce dental-age estimations that did not differ significantly from the real age of the teeth, obtaining a mean error between 0.5 and 1.8 years and a standard deviation of this error between 9.0 and 11.3 years. When using the radiological technique according to the original protocol, all three examiners produced age estimations that were statistically comparable to the real age of the teeth with a mean error of 0.5-2.5 years and a standard deviation of 4.6-9.8 years. For both techniques, intra-observer differences were observed. Based on the results of this study, it can be concluded that both non-destructive dental-age estimation techniques were able to produce reasonably accurate dental-age estimations, at least when these techniques were applied appropriately. However, the forensic odontologist is recommended to use different age estimation techniques and perform repetitive measurements in order to verify the reproducibility of the calculations performed.     

Age calculation using X-ray microfocus computed tomographical scanning of teeth: a pilot study

To correlate dental age with an individual's chronological age based on the calculated volume ratio of pulp versus tooth volume measured, an X-ray microfocus computed tomography unit (microCT) with 25 microm spatial resolution was used to non-destructively scan 43 extracted single root teeth of 25 individuals with well-known chronological age. Custom-made analysis software was used by two examiners to obtain numerical values for pulpal and tooth volume. The ratio of both was calculated and statistically processed. No significant intra- or inter-examiner differences were found. In fact, a very strong concordance correlation coefficient was found. Linear regression analysis showed a coefficient of determination (r) of 0.31 which suggests that there is a rather weak correlation between the volume ratio of pulp versus tooth and biological age. Although rather time consuming, this technique shows promising results for dental age estimation in a non-destructive manner using X-ray microfocus computed tomography.     

Tendenzen der Gegenwartskultur: Zwischen Normalismus und Vergewöhnlichung

Der Aufsatz thematisiert in konzeptueller und empirischer Hinsicht Aspekte von Normalität. Zum einen werden verschiedene Ansätze behandelt, die Normalität als eine Ebene und als ein Resultat praktischer Wirklichkeitskonstruktion entwerfen. Als besonders anschlussfähig und weiterführend erweisen sich Konzepte und Argumente der Differenzierungstheorie, der Diskurstheorie, der Zivilisationstheorie, der Habitustheorie, der Rahmentheorie und der Stigmatheorie. Zum anderen ist es das Ziel, gegenläufige Entwicklungstendenzen in der Normalitätskonstruktion der Gegenwartskultur zu identifizieren und aufzuklären. Diese Tendenzen werden unter den Titeln ?Normalismus“ (J. Link) und ?Vergewöhnlichung“ (J. Weiß) diskutiert.