Clinical evaluation and management of children with suspected physical abuse

Evaluating and managing children with suspected physical abuse is challenging. Few single injuries are pathognomonic for abuse and, as a result, child abuse is easily missed. As such, a healthy bit of skepticism is needed to recognize and protect abused children. The medical history and clinical presentation should guide evaluation. Medical providers must consider the differential diagnosis, epidemiology of injuries, and child development to inform the assessment. In this review, we address evidence-based recommendations to inform child physical abuse evaluations. We also discuss the role of medical providers in communicating with families, mandated reporting and interpreting medical information for investigative agencies and other non-medical colleagues entrusted with protecting children.

The development of a colorimetric scale as a visual aid for the bruise age determination of bite marks and blunt trauma

Medical examiners and forensic odontologists are frequently asked to establish the age of a bruise or bitemark on either a living and deceased subjects. The age of bruising has an important medico-legal significance and may be relevant in the investigations related to such crimes as child abuse, domestic violence and homicide. A colorimetric scale for forensic photography based on the colors of the bruise itself, has never been proposed due to the fact that photographic reproduction of color is unreliable and depends on several factors; the camera used, lighting, printer and photo-editing color calibration. The authors propose two colorimetric scales, both with and without linear measurements, and with 90° angulations, six bruise colors, and three circles with black and white calibrators, which are to be used for the forensic photography of injuries involving the epidermis of Caucasian subjects. The two scales could also be employed on living subjects during different stages of the healing process, or on cadavers in order to provide evidential documentation, image verification and analysis. Such an aid would provide a reliable standard condition and allow for color calibration. The colors represented on the scales would be an aid for the interpretation and objectivity required in estimating the age of the bruise, particularly when the analysis is made directly onto computer images prior to printing. The proposed colorimetric scales do not attempt to give a definitive account of the diverse scientific methods available for the assessment of the age of bruising. The observation of a large sample of blunt trauma and bite mark injuries employing the proposed colorimetric scales would be needed in order to verify and validate the use of these scales. It should be borne in mind that bruise age estimation requires an expert opinion with several degrees of accuracy and variability involved. The age of a bruise cannot be determined by color alone.

Considerations for Gross Autopsy Photography

Photography has been a mainstay of autopsy documentation for many years. Recent advances in digital photography have increased its prominence. Good photographic practice requires an understanding of how a camera works, basic optics, and basic digital processes, as well as traditional compositional issues. The quality of autopsy photography is a function both of the skill of the photographer and how the imaging process fits into the autopsy workflow. Numerous technical issues affect image quality, including the type of sensor, the type of camera back, the lens, the aperture, the shutter speed, and lighting. The choice of output format and procedures for archival of images is important. A number of special processes may be part of autopsy pathology including epiluminescence, indirect ophthalmoscopy, and ultraviolet and infrared photography. Postprocessing of images is common, but must be documented.

Experimental study of bite mark injuries by digital analysis

This study was based on a morphometric analysis of bite marks starting from the quantitative definition of the anterior teeth by the geometric acquisition of the "injuries," using bite marks impressed on pig skin and plastic. Each mark was photographed and acquired. A dedicated program automatically supplied the values of the shape factors and the areas of the pattern geometric figures. The values obtained for the homologous samples were compared to the heterologous values. Statistical comparison was made of the sets by linear regression, determining the correlation coefficient and the determination coefficient for each value. Results showed only 4.8% and 2% of overlap between homologous and heterologous values. This study was carried out in attempting to quantitatively define the anterior teeth of the human dentition and the procedure described and the results obtained support the advantage of morphometric studies and computer-aided programs in this study of bite marks.

Comparison of simulated human dermal bitemarks possessing three-dimensional attributes to suspected biters using a proprietary three-dimensional comparison

The infliction of a bite is a four-dimensional space-time event that is ideally analyzed with three-dimensional (3-D) technology. Comparison of 2-D images (photographs) of a bitemark with a 3-D replica of a suspect's dentition is challenging. The authors present a technique that produces 3-D images of indented marks and dentitions for comparisons. Study models and corresponding dental-wax bites were digitized by 3-D scanning, and comparison overlays were generated using DentalPrint software. The effectiveness of the method was analyzed by determining the area under receiver operating characteristic (ROC) curve and the sensitivity, specificity and 95% confidence interval (CI) for each cut-off point. An area under the ROC curve of 0.953 (SE=0.029; 95% CI=0.893-0.985) and high sensitivity and specificity values were obtained for 104 comparisons made by an expert examiner, who correctly identified 92.3% of matching dentitions and 98.7% of non-matching dentitions. This technique can be considered a highly accurate method of bitemark analysis, although indentations must be present in the injury, limiting the cases that can be resolved. A comparative study of the same dentitions using 2-D bitemark photography confirmed the superiority of the new approach.

The barriers to achieving an evidence base for bitemark analysis

Forensic dentistry is the union of two scientific disciplines, both of which are undergoing a renewed scientific rigor. In forensic science the advent of the Daubert ruling has required that judges assess the forensic value of 'expert testimony' ensuring that techniques, methodologies and practices are not only commonly accepted (as was the previous hurdle during the Frye era) but that error rates, assessment of reliability and validation studies are published to support their use. This new degree of judicial scrutiny has been mirrored in the field of dentistry itself, where organisations search and summarise randomised controlled trials in order to recommend best practice and devise clinical care pathways that are firmly grounded in proven scientific research. Despite the obvious drive from both of these professions, forensic dentistry, and in particular the sub-discipline of bitemark analysis, has been remarkably slow to address the obvious deficiencies in the evidence base that underpins this element of forensic science. Reviews of the literature reveal that the vast majority of published works are case reports, and very little primary literature exists. This paper reviews those studies that have assessed aspects of bitemark analysis including the crucial issue of the uniqueness of the human dentition; the application of transparent overlays and the application of statistical probabilities in bitemark conclusions. There are numerous barriers to undertaking high quality research in the field of bitemark analysis, the most important of which is the use of a gold-standard that is acceptable both in terms of diagnostic research but is also forensically relevant. If bitemark analysis is to continue to play a role in the judicial process then there is an urgent need for high quality studies that meet the levels of forensic and scientific scrutiny applied to other disciplines within the criminal justice system. Studies are required to determine not that the human dentition is unique, but how this asserted uniqueness is represented on human skin and other substrates. The error rates associated with the analysis of bitemarks are required on a procedural level as well as an individual practitioner basis and scales and interpretative indices of bitemark severity and forensic significance should be validated and introduced into common use.

Analysis of patterned injuries and injury-causing instruments with forensic 3D/CAD supported photogrammetry (FPHG): an instruction manual for the documentation process

Forensic 3D/CAD supported photogrammetry (FPHG) is a method of recording and documenting the surface of small objects, thus enabling a three-dimensional image of these objects in virtual space. With this representation on the computer screen the course of forensically relevant events can be reconstructed. The procedure allows for examining patterned injuries of skin, soft tissue or bones for matching potentially incriminated instruments in shape, size and angle.3D recording of objects to be examined requires taking series of photographs. A computer system then calculates the position in space of certain points on the surface of the objects and subsequently produces 3D data models of the objects. Using a 3D/CAD program these data models are used to generate graphic true-to-object volume models. The objects in question can then be moved against each other arbitrarily on the screen-depending on the questions to be answered-in order to compare them and possibly establish their congruence. This article covers the state of the art in FPHG procedures in the form of a step-by-step instruction. It also illustrates the wide range of FPHG applications.

Forensic dentistry and human bite marks: issues for doctors

The human dentition can be used as a weapon of attack or defence. Bite mark injuries are common in cases of sexual assault, child abuse and homicide. Many bite injuries are first seen in casualty departments where quick and proper recovery of evidence can assist in analysing these injuries. This article describes different bite injuries, collection of evidence and comparative analysis methods.

A forensic classification of distortion in human bite marks

The occurrence of distortion in human bite marks is well recognised. A forensic classification of distortion is suggested which is based upon the causative factors and their inter-relationships. The terms primary distortion and secondary distortion are introduced and described. The objective of this classification is to emphasise the need for a scientific approach to the recognition and interpretation of the types of distortion found in human bite marks. The relationships between distortion, distinctive features and superimposition techniques in bite mark analysis are discussed.

The scientific basis for human bitemark analyses--a critical review

This article presents a discussion of the scientific basis for human bitemark analyses. Using a review of the literature, the major areas of contention within the field are assessed: including the accuracy of bitemarks on skin, the uniqueness of the human dentition, and analytical techniques. The review revealed a lack of valid evidence to support many of the assumptions made by forensic dentists during bitemark comparisons. The new level of judicial scrutiny of such scientific evidence is likely to emphasise this lack of knowledge upon which bitemark analysis relies. The authors call for a more scientific and evidence-based approach to forensic dental research.