Journal of Forensic Radiology and Imaging最新文献

In the application of scientific human skeletal variation in medico-legal matters, virtual anthropology is the current technique performed to examine skeleton and its body parts. Digital imaging techniques are used in many areas of dentistry and forensic dentistry. Among all digital imaging modalities, digital periapical radiography (PR) are the most widely used, however, new contemporary imaging techniques micro-computed tomography (Micro-CT) can be also used. The aim of this study was to assess the accuracy and reliability of enamel and dentin thickness measurement through intra and inter-observer error analysis, and comparison was made between periapical radiographs and Micro-CT methods. In this study 15 maxillary first premolar were used which extracted for various reasons. Enamel and dentin thicknesses and maximum cervical crown widths (MCCW) of 15 premolar teeth were examined in both Micro-CT and periapical radiographs. The results obtained with the exact maximum cervical crown widths were compared Image J software version. A digital caliper was used to measure the actual MCCW of the teeth. Results exhibited no significant differences in the measurements by the intra or inter-observer error analyses. The intraclass correlation coefficients (ICC) were more than 0.95 by both intra and inter-observer error analyses. There was significant differences in the measurements by PR and Micro-CT methods. By parameters, Micro-CT showed the highest R value (0.962) with the least error in different methods and observers. In conclusion, dentin and enamel measurements by Micro-CT was highly accurate and reliable as in the conventional method (PR). Micro-CT evaluations should be recommended for implementation in the future anthropological studies especially in countries with limited source of dental data.

Gross similarities between human hand/foot bones and bear paws have been well-documented. Macroscopic skeletal analyses provide insight into species origin when whole bones are recovered but are frequently rendered inapplicable when bones are fragmented. In these scenarios, histological techniques are often applied; though specific research focusing on the quantification of bear bone microstructure remains scarce. We hypothesized that 3D analysis of bear cortical bone microarchitecture provides a more representative and accurate means to infer bone attribution to species from fragmented metapodials. Methods included visualizing and quantifying bone microstructural parameters using micro-Computed Tomography (µCT). Third metacarpals and metatarsals from mature black bears and humans were assessed using 3D analyses. Micro-CT experiments were carried out using a laboratory X-ray system at The University of Akron. Projections were reconstructed and cylindrical Volumes of Interest (VOIs) were identified within each bone sample. Variables measured within the VOIs included: total volume (TV), total canal volume (Ca.V), canal number (Ca.N), average canal diameter (Ca.Dm), and cortical porosity (Ca.V/TV). Between-species t-tests revealed that both Ca.N and Ca.Dm significantly differed between human and bear metapodials. Qualitative features including osteon banding and resorption bays were more prevalent in bear metapodials. The 3D data for this study were obtained non-destructively and reveal the usefulness of laboratory µCT as a diverse and novel tool for the anthropologist. Results demonstrated differences between the human and black bear third metapodials, supporting the hypothesis that a microstructural comparison is necessary for fragmentary bone identification of human and bear metapodials.

Fractography is the study of fracture surface morphology and its relationship to crack propagation. Recent work has demonstrated the utility of fractography for interpreting crack propagation and impact direction in fractured bones as part of forensic anthropological trauma analyses on skeletonized remains. In this proof-of-concept work, we assess whether the science of fractography can be applied using CT scans of bone fractures. For CT scans to have practical potential for fractographic analysis, the resolution must sufficiently capture and reveal fracture surface features such as bone mirror, arrest ridges, wake features, and cantilever curl. A routine forensic postmortem CT of a fractured femur resulting from a motor vehicle accident was assessed from a volume rendering. Some of the smaller surface features were not observed due to the resolution of the CT scan, but several larger fractographic features were observed, permitting an interpretation of crack propagation and force direction. It therefore appears that fractography can be applied to CT scans and may have utility in forensic contexts for evaluating skeletal trauma. This approach may also have applications in clinical contexts, or in forensic investigations involving the injured living.

Epiphyseal plates union gives valuable information about age. The knee joint is an articulation of three long bones so it is an important anatomical site to be considered and it can help for assessment of the age group of 10–20 years particularly. Also the knee can carry important information for sex identification through measuring the femur bicondylar distance and various patellar dimensions. The aim of this study is to assess the value of radiographic knee examination for estimation of age and sex in Egyptian population. Age identification is studied in correlation to the epiphyseal union of distal end of femur, proximal end of tibia, proximal end of fibula and the total score of the knee joint (SKJ). Sex identification is studied in relation to the femur bicondylar distance, patellar breadth, length, depth and volume. Our study included a random sample of 146 knee radiographs from patients who visited Beni Suef university hospital radiology center for diagnostic causes. All the subjects from both sexes aged from 10 to 20 years. Results showed that SKJ has the best correlation to age in comparison to each individual bone score alone for both male (r = 0.92) and female (r = 0.89) subjects with accuracy of 58%. Females showed earlier growth that is statistically insignificant. The femur bicondylar distance showed statistically significant sexual dimorphism with a mean value of 73.92 mm in males and 65.68 mm in females, accuracy is 79.4%. But the patellar sexual differences are statistically insignificant.

Purpose The spleen is the largest lymphatic organ in the human body. Its appearance and weight during autopsy can be relevant for the determination of cause of death. Postmortem computed tomography (PMCT) supplements traditional autopsy. The aims of this study were to investigate spleen radiodensity on PMCT with regards to prior hospitalization, spleen macroscopy, cause of death, and the utility of PMCT for estimation of spleen weight (SW).

Methods Spleen density, width (W), thickness (T), greatest axial surface (S) and presence or absence of contrast medium (CM) residues were evaluated on PMCT axial images of 1035 cadavers retrospectively. Corresponding autopsy reports were reviewed for cause of death, evidence of prior hospitalization, SW at autopsy and macroscopic features of the spleen, like congestion, pallor or contraction.

Results Spleen density on PMCT was significantly higher for cases with CM and lower for hospital deaths. Multiple organ failure as cause of death showed significantly lower spleen density than fatal hemorrhage, intoxication, asphyxia-strangulation, hypothermia and metabolic disorders. No significant density differences were noted for different macroscopic spleen findings. Spleen W, T and S strongly correlate with SW at autopsy and formulas for estimating SW were derived based on linear regression models.

Conclusions Presence of CM, prior hospitalization and organ failure, fatal hemorrhage, intoxication, asphyxia-strangulation, hypothermia and metabolic disorders as causes of death have an influence on spleen's radiodensity on PMCT. Routine spleen measurements on PMCT can be used to predict SW prior to autopsy or estimate SW when complete forensic autopsy is not conducted.

Following a mass fatality event there is a requirement to establish the identities of the deceased individuals as quickly as possible, but with sufficient certainty. Comparison of post-mortem dentition with ante-mortem records remains one of the most cost-effective methods of achieving this reliably and in a timely manner. The relatively recent introduction of post-mortem CT scanning into the Disaster Victim Identification (DVI) environment has brought with it an abundance of additional detailed information that can be used in a variety of novel ways. Here we present a case where 3D printing was used to produce a model of a victim's dentition, enabling confident odontological identification without resorting to disfiguring incisions in a charred body. On-site access to a 3D printer of sufficient quality meant that there was no significant delay in the identification process, and the cost of consumables used to manufacture the model totalled less than £1.

Objectives

: To compare the quantified radiopacity of five bulk fill composites in digital dental radiographs.

Material and methods

: An in-vitro observational study was performed with five dental restoration materials: I) Bulk Fill Surefil SDR+ flow® (Dentsply Sirona®, York, PA, USA), II) Bulk Fill Sonic Fill® (Kerr Corp.®, Orange, CA, USA); III) Filtek Bulk Fill flow® (3M Company®, Maplewood, MN, USA); IV) Tetric N Ceram Bulk Fill® (Ivoclar Vivadent®, Schaan, Liechtenstein); and V) Aura® (SDI Ltd.®, Victoria, Australia). Digital radiographs were taken standardly from four samples of each composite (n = 20). The radiopacity inherent detected in the radiographs was quantified using a 9-level aluminum scale.

Results

: ANOVA and Tukey's test showed statistically significant differences between the radiopacity of all bulk fill composites (p<0.0001), except between I and IV (p = 1.0). Spearman's outcomes revealed that only composite I had positive moderate (rS=0.63) correlation with the respective radiopacity level in the aluminum scale (p = 0.027).

Conclusion

: Most of the bulk fill composites addressed in this study were distinguishable from each other based on their radiopacity. The identification of type and even brand of composites may be a promising task in human identification. However, this procedure remains challenging and the scientific evidence behind it is still scarce in the forensic literature.