Age estimation using third molar maturation based on Demirjian’s criteria

Dental age estimation is routinely used in human identification, in both the living and the dead. Teeth follow a predictable pattern of eruption and maturation that can be assessed radiographically in the living, allowing experts to estimate an individual’s age. Third molars develop much later than the other permanent teeth, and can be used to estimate age of individuals nearing the age of maturity. Ability of third molar maturation when graded using Demirjian’s method in ascertaining whether an individual has attained the medicolegal ages of 16 and 18 years has not yet been verified. The present study involved assessing the third molar maturation of 220 individuals of a training set using Demirjian’s scoring system, generating regression models to estimate age using the third molar maturity scores, applying these models on a test set of 40 individuals, and calculating the mean difference (MD) and the mean absolute error (MAE) between the chronological and estimated ages of the test set participants. It was observed that the lowest mean difference and mean absolute error was observed for the maturation of the left mandibular third molar (MD = 1.05 years, MAE = 2.09 years). Boxplots generated in the study report that the third molar maturation stages given by Demirjian can identify whether an individual has attained the medicolegally significant ages of 16 and 18 years of age.     

Demirjian’s stages and Cameriere’s third molar maturity index to estimate legal adult age in Peruvian population

ObjectiveTo compare the accuracy of Demirjian’s stages (DS) and Cameriere’s third molar maturity index cut-off value (I_3M < 0.08) to estimate the age of majority on panoramic radiographs (OPTs) from the dental clinic of the Scientific University of the South (UCSUR), Lima, Peru.MethodsAn observational cross-sectional study was conducted on the sample of 208 digital panoramic radiographs of patients aged 14–22 years examined during 2015 in UCSUR. The left lower third molars were analyzed using Adobe Photoshop® CS6. An effectiveness of specific DS and I_3M < 0.08 was evaluated by using accurate classification, sensitivity, specificity, positive (LR+) and negative (LR−) likelihood ratios and Bayes post-test probability (p).ResultsOnly G and H stages were practical for classify adults and minors in the tested sample, while I_3M < 0.08 showed the best performance in both sexes. For I_3M < 0.08, the accurate classification, sensitivity and specificity were 0.96, 0.96, 0.96 and 0.90, 0.84 and 0.95 in males and females, respectively. Values of LR+, LR− and p were 24.96, 0.04, 0.97 and 15.68, 0.17, 0.95 in males and females, respectively.ConclusionThe specific cut-off value of third molar maturity index (I_3M < 0.08) showed to be more accurate in discriminating adults and minors in Peruvian sample when a test with high sensitivity and specificity is required.     

Cameriere’s third molar maturity index in assessing age of majority: a study of a French sample

International Journal of Legal Medicine - Forensic age estimation is a challenging field in forensic sciences because of the increase of migratory flows. Medicolegal age assessment is a key point...     

Dental age estimation in the living after completion of third molar mineralization: new data for Gustafson’s criteria

There is a need for dental age estimation methods after completion of the third molar mineralization. Degenerative dental characteristics appear to be suitable for forensic age diagnostics beyond the 18th year of life. In 2012, Olze et al. investigated the criteria studied by Gustafson using orthopantomograms. The objective of this study was to prove the applicability and reliability of this method with a large cohort and a wide age range, including older individuals. For this purpose, 2346 orthopantomograms of 1167 female and 1179 male Germans aged 15 to 70 years were reviewed. The characteristics of secondary dentin formation, cementum apposition, periodontal recession and attrition were evaluated in all the mandibular premolars. The correlation of the individual characteristics with the chronological age was examined by means of a stepwise multiple regression analysis, in which the chronological age formed the dependent variable. Following those results, R ² values amounted to 0.73 to 0.8; the standard error of estimate was 6.8 to 8.2 years. Fundamentally, the recommendation for conducting age estimations in the living by these methods can be shared. The values for the quality of the regression are, however, not precise enough for a reliable age estimation around regular retirement date ages. More precise regression formulae for the age group of 15 to 40 years of life are separately presented in this study. Further research should investigate the influence of ethnicity, dietary habits and modern health care on the degenerative characteristics in question.

     

Estimating a child’s age from an image using whole body proportions

The use and distribution of child pornography is an increasing problem. Forensic anthropologists are often asked to estimate a child’s age from a photograph. Previous studies have attempted to estimate the age of children from photographs using ratios of the face. Here, we propose to include body measurement ratios into age estimates. A total of 1603 boys and 1833 girls aged 5–16 years were measured over a 10-year period. They are ‘Cape Coloured’ children from South Africa. Their age was regressed on ratios derived from anthropometric measurements of the head as well as the body. Multiple regression equations including four ratios for each sex (head height to shoulder and hip width, knee width, leg length and trunk length) have a standard error of 1.6–1.7 years. The error is of the same order as variation of differences between biological and chronological ages of the children. Thus, the error cannot be minimised any further as it is a direct reflection of a naturally occurring phenomenon.

     

The comparison between measurement of open apices of third molars and Demirjian stages to test chronological age of over 18 year olds in living subjects

This paper concerns a method for assessing adult age based on the relationship between age and the third molar maturity index (I_3M), which is related to the measurement of the open apices of the third molar. Furthermore, this method was compared to those based on Demirjian’s stages G and H. The sample consisted of 906 Caucasian individuals aged between 14 and 23 years (53.6% females and 46.4% males). Orthopantomographs were analyzed by two observers and calibrated by means of the concordance correlation coefficient for the reproducibility of the third molar maturity index (I_3M) and κ statistics for reproducibility of the Demirjian stages. Probabilities for an individual to be older than 18 years of age (adult age) were derived using the measurements of the third molar maturity index (I_3M). These results were exploited to set out a threshold value to assign an individual to juvenile or adult age. A cutoff value of I_3M = 0.08 was taken. The sensitivity of this test was 70% and specificity was 98%. Furthermore, the proportion of individuals with a correct classification was 83%. The results of the test showed a better specificity when compared to the choice of stage G and a better sensitivity when compared to the choice of stage H for adult age.     

Accuracy of the London Atlas,Haavikko’s Method and Cameriere’s European Formula of dental age estimation in Turkish children

Age estimation is a mandatory procedure when the chronological age is unknown or uncertain. Dental development is the preferred characteristic for estimating a child's age. There are many methods for dental age estimation, but their reliability can differ between populations. This study compared the accuracy of three of these methods—the London Atlas (LA), Haavikko's method (HM), and Cameriere's European formula (CF)—in Turkish children living in northwestern Turkey. Panoramic radiographs of 980 children from northwestern Turkey aged between 6.00 and 14.99 years were examined for the whole study group and separately for different ages and sexes by all three methods. Statistical differences between chronological age and dental age were tested using the paired sample t-test and the Wilcoxon signed-rank test. The LA, HM, and CF accuracies were determined based on the mean absolute error. Spearman's rank correlation coefficient showed that the correlation between chronological age and dental age for both sexes was linear for all methods. The LA overestimated the chronological age by 0.09 years, while HM and CF underestimated it by 0.49 and 0.11 years, respectively. The difference between dental age and chronological age was significant in all samples, for all methods, except for the LA in boys. When boys, girls, and the total sample were evaluated, values with the lowest mean absolute error were obtained by HM and were statistically significant in all three groups. Therefore, HM is more accurate than the LA and CF for dental age estimation in Turkish children living in northwestern Turkey.     

Study of the ethnicity’s influence on the third molar maturity index (I3M) for estimating age of majority in living juveniles and young adults

International Journal of Legal Medicine - Estimation of age of majority has important applications in the forensic daily practice because of the increasing demand for age estimates of unaccompanied...     

Above or below 14 years? An orthopantomographic study based on chronological course of eruption of mandibular premolars and second molars in a sample of south Indian children

In the context of dental age assessment, two significant factors can be studied; tooth mineralisation and tooth emergence. Little is known about the role of a second molar eruption in forensic age estimation. This paper aims to contribute to forensic age estimation using an age threshold of 14 years, studying the eruption stages of permanent mandibular premolars and second molars. Totally 640 orthopantomograms (OPGs) of south Indian children, aged between 10 and 18 years, were evaluated using Olze et al. staging of tooth eruption stages (A–D). Spearman's rho correlation showed a strong, positive, and statistically significant correlation between the chronological age and the eruption stages of both sexes' teeth. Accuracy, sensitivity, specificity, likelihood ratios, and post-test probability values were calculated for all tested teeth. The best performance to discriminate individuals above or below 14 years showed stage D in second molars. The sensitivity varied between 89% and 94% and specificity between 75% and 84%, respectively. Receiver operating characteristic curve analysis revealed high diagnostic performance for stage D, with area under the ROC curve (AUC) values of 84% and 85% for tooth 37 and 85% and 83% for tooth 47 in males and females, respectively. In conclusion, it is possible to predict age over 14 years in south Indian children using tooth emergence stages from OPGs with a relatively high interobserver agreement and good diagnostic accuracy. However, there are some limitations and, therefore, must be used in conjunction with other methods.     

Dental age estimation: periodontal ligament visibility (PLV)—pattern recognition of a conclusive mandibular maturity marker related to the lower left third molar at the 18-year threshold

International Journal of Legal Medicine - The purpose of this study was to explore the applicability of periodontal ligament visibility (PLV) at the 18-year threshold. This mandibular maturity...     

Premolar maturity index (IPM) for indicating legal age 12 years in a sample of south Indian children – A digital pantomographic study

Legal age of 12 years has been set as the minimum age of criminal responsibility in many countries. This paper concerned a method for predicting the legal age 12 years based on the maturation of lower first and second premolars. The sample consisted of 900 digital pantomographs of south Indian children (450 males, 450 females) aged between 8 and 16 years. Among them, 580 DPTs were used as test sample and 320 DPTs as validation sample. New cut-offs at the age threshold 12 years were determined by using the measurement of open apices in first premolars (IPM1 < 0.10), second premolars (IPM2 < 0.14) and the combined method (IPM1 + IPM2 < 0.12). The sensitivity (Se), specificity (Sp) and posttest probability (PTP) were established. For IPM1 < 0.10, the Se, Sp and PTP were 92.4 %, 91.3 % and 91.1 % for males and 90.8 %, 87 % and 86.5 % for females. For IPM2 < 0.14, they were 92.6 %, 93.6 % and 93.4 % for males and 91.5 %, 83.1 % and 83.4 % for females. And, for the combined predictor (IPM1 + IPM2 < 0.12), these values were 92.6 %, 94.8 % and 94.6 % and 90.5 %, 84.9 % and 84.7 % in males and females respectively. The best score of positive predictive value and specificity was obtained for males with the combined predictor (IPM1 + IPM2 < 0.12) and with single predictor (IPM1 < 0.10) for females. To conclude, the combined predictor has resulted in better discrimination in males, while in females the single predictor (IMP1 < 0.10) did slightly better. Further studies are warranted to test the combination of dental and skeletal indicators for the prediction of 12 years in the studied population.     

Validation of Roberts’ method using root canal width patterns as a mandibular maturity marker in determining the 18-year threshold

International Journal of Legal Medicine - The South African Bill of Rights and the Children’s Act define a ‘child’ as a person under the age of 18 years. The age of 18 years is...     

Prognostic relevance at 5 years of the early monitoring of neoadjuvant chemotherapy using 18F-FDG PET in luminal HER2-negative breast cancer

Purpose

The objective of this study was to evaluate, in the luminal human epidermal growth factor receptor 2 (HER2)-negative breast cancer subtype, the prognostic value of tumour glucose metabolism at baseline and of its early changes during neoadjuvant chemotherapy (NAC).

Methods

This prospective study included 61 women with hormone-sensitive HER2-negative breast cancer treated with NAC. ¹⁸F-Fluorodeoxyglucose (FDG) positron emission tomography (PET) was performed at baseline. Hepatic activity was used as a reference to distinguish between low metabolic and hypermetabolic tumours. In hypermetabolic tumours, a PET exam was repeated after the first course of NAC. The relative change in the maximum standardized uptake value of the tumour (?SUV) was calculated.

Results

Nineteen women had low metabolic luminal breast cancers at baseline, correlated with low proliferation indexes. Forty-two women had hypermetabolic tumours, corresponding to more proliferative breast cancers with higher Ki-67 expression (p?=?0.017) and higher grade (p?=?0.04). The median follow-up period was 64.2 months (range 11.5–93.2). Thirteen women developed recurrent disease, nine of whom died. Worse overall survival was associated with larger tumour size [>5 cm, hazard ratio (HR)?=?6.52, p?=?0.009] and with hypermetabolic tumours achieving a low metabolic response after one cycle of NAC (ΔSUV?<?16 %, HR?=?10.63, p?=?0.004). Five-year overall survival in these poor responder patients was 49.2 %. Overall survival in women with low metabolic tumours or hypermetabolic/good response tumours was 100 and 96.15 %, respectively.

Conclusion

In luminal HER2-negative breast tumours, tumour metabolism at baseline and changes after the first course of NAC are early surrogate markers of patients’ survival. A subgroup of women with hypermetabolic/poorly responding tumours, correlated with poor prognosis at 5 years, can be identified early. These results may guide future studies by tailoring the NAC regimen to the metabolic response.     

Functional volumetric analysis of striatum using F-18 FP-CIT PET in patients with idiopathic Parkinson’s disease and normal subjects

Objective

We applied a simple isocontour volume-of-interest (VOI) method to analyze the whole striatum in an F-18 FP-CIT PET image and to investigate the usefulness of the method in differentiating healthy subjects from idiopathic Parkinson’s disease (IPD) patients and the correlation of the value of functional volume parameters with the motor symptoms in patients with IPD.

Methods

Forty-three IPD patients and 23 age-matched healthy controls underwent F-18 FP-CIT PET. Using a dedicated workstation, VOIs for the whole striatum were drawn automatically with the gradient delineation method. The SUVmax, SUVmean, functional volume (FV), striatal volume activity (SVA), striatal-specific binding (SSB), and volume-specific uptake ratio (VSUR) were compared between the IPD patients and the normal subjects. In the IPD patients, the correlation between the clinical factor and the functional parameters was assessed.

Results

The SUVmax, SUVmean, FV, SVA, SSB, and VSUR were significantly lower in the IPD patients than in the normal subjects. In the receiver operating characteristic analysis, those parameters had significant and good-to-excellent accuracy. In the patients with IPD, a moderate negative correlation was revealed between the SUVmax and H&Y stage, the SUVmean and H&Y stage, SVA and H&Y stage, the VSUR and H&Y stage, the FV and bradykinesia, and the SVA and bradykinesia.

Conclusion

The functional volumetric analysis of the striatum based on simple isocontour VOI was a useful method of analyzing the F-18 FP-CIT PET image. Not only can it be easily applied in daily clinical practice, but it can also be used as a clinical parameter to discriminate IPD and to correlate it with the disease severity.

     

Quantitative analysis of the effects of donepezil on regional cerebral blood flow in Alzheimer’s disease by using an automated program, 3DSRT

INTRODUCTION: Donepezil, an acetylcholinesterase inhibitor, has been reported to have an effect that improves cerebral blood flow (CBF) alongside its primary effect on memory function. The aim of this study was to investigate the effects of long-term, low-dose donepezil therapy on blood perfusion in Alzheimer's disease (AD) by using a fully automated regional CBF quantification program named 3DSRT. MATERIALS AND METHODS: Fifteen subjects with mild to moderate AD according to NINCDS/ADRDA criteria underwent 99mTc-ethylcysteinate dimer (ECD) brain perfusion single photon emission computed tomography (SPECT) twice with an interval of 55.1 +/- 11.0 weeks. The dose of donepezil was fixed at 5 mg/day following the induction period (3 mg/day) of 2 weeks. Clinical efficacy of donepezil was assessed by using the Mini-Mental State Examination (MMSE). The results of SPECT imaging under exactly identical conditions were analyzed by 3DSRT, which enables us to perform a very objective assessment. RESULTS: Despite a decrease of the MMSE score from 20.9 +/- 4.7 to 18.7 +/- 5.7, CBF was increased in almost all cerebral areas except the left temporal segment. The increase was statistically significant in the left callosomarginal, right central, and bilateral pericallosal and lenticular nucleus segments. CONCLUSION: Thus far, no direct cerebrovascular effects have been reported for donepezil. We hypothesize that these CBF-promoting effects of donepezil might be related to increased neuronal activity and enhanced connection of neurons.     

Clinical impact of amyloid PET using 18F-florbetapir in patients with cognitive impairment and suspected Alzheimer’s disease: a multicenter study

Annals of Nuclear Medicine - Amyloid positron emission tomography (PET) can reliably detect senile plaques and fluorinated ligands are approved for clinical use. However, the clinical impact of...