Morphologic patterns of lip prints in a portuguese population: a preliminary analysis

Lip prints are thought to have the ability to distinguish individuals and, hence, have a potential use in human identification purposes. However, questions remain regarding their utility for sex determination. This study aimed to classify lip prints for different individuals in a Portuguese population and to determine whether sex differences exist. Lip prints of 25 females and 25 males were obtained using dark-colored lipstick and cellophane tape. Lip prints were analyzed using a magnifying lens and classified according to the Suzuki and Tsuchihashi classification. A Type II pattern was found to be most common. A comparison of lip-print patterns between males and females showed results with a statistically significant difference: Type III pattern was most common in males, and a Type II pattern in females. This study corroborates the hypothesis that lip prints are able to distinguish individuals and may be useful in sex determination.     

Computer‐aided Dental Identification: An Objective Method for Assessment of Radiographic Image Similarity*

Abstract: A pilot study evaluated a computer‐based method for comparing digital dental images, utilizing a registration algorithm to correct for variations in projection geometry between images prior to a subtraction analysis. A numerical assessment of similarity was generated for pairs of images. Using well‐controlled laboratory settings, the method was evaluated as to its ability to identify the correct specimen with positive results. A subsequent clinical study examined longitudinal radiographic examinations of selected anatomical areas on 47 patients, analyzing the computer‐based method in making the correct identification based upon a threshold level of similarity. The results showed that at a threshold of 0.855, there were two false negative and two false positive identifications out of 957 analyses. Based on these initial findings, 25 dental records having two sets of full mouth series of radiographs were selected. The radiographs were digitized and grouped into six anatomical regions. The more recent set of films served as postmortem images. Each postmortem image was analyzed against all other images within the region. Images were registered to correct for differences in projection geometry prior to analysis. An area of interest was selected to assess image similarity. Analysis of variance was used to determine that there was a significant difference between images from the same individual and those from different individuals. Results showed that the threshold level of concordance will vary with the anatomical region of the mouth examined. This method may provide the most objective and reliable method for postmortem dental identification using intra‐oral images.     

Antemortem dental records: attitudes and practices of forensic dentists

This study was designed to provide insight concerning the attitudes and practices of forensic dentists regarding antemortem dental records reviewed for purposes of dental identification. Forensic dentists were invited to participate in a 10 item survey. The majority of the respondents reported a considerable amount of experience in dental identifications of the deceased. Sixty-six percent reported having suspected dental negligence or fraud in their antemortem record reviews. Only 17% believe that a forensic dentist should report suspected dental negligence, while 31% agree that dental fraud should be reported. Their response to additional issues addressed in the study suggests diversity in the practices and attitudes of forensic dentists in the use of antemortem dental records. In conclusion, opening a dialogue among practicing forensic dentists may lead to a standardized set of recommendations by the appropriate societies in the forensic dental community.     

Morphological pattern of palatal rugae in children of Davangere

The aim of this study was to identify and compare the rugae pattern between males and females of two different communities in the city of Davangere, Karnataka, India, which may be an additional method of identification in cases of crimes or communal riots. Elastomeric impressions of the maxillary arch of 100 selected children were made; casts were poured in Type IV stone. The method of identification of rugae pattern followed was that of Lysell and Thomas and Kotze, which includes the number, shape, direction, and unification of rugae. The study revealed no significant difference in the total number or length of rugae between the two communities and sexes. However, with regard to shape and unification, females showed a significantly higher diverging rugae type while males had a significant number of circular and converging type of rugae. Also, discrimination function analysis allowed a moderate differentiation of the population. Hence, the rugae pattern can be an additional method of differentiation in conjunction with the other methods such as visual, fingerprints, and dental characteristics in forensic sciences.     

The Use of Radio-Frequency Identification Tags for Labeling Dentures—Scanning Properties

Abstract:  The inclusion of radio-frequency identification (RFID)-tags within dental prostheses has been suggested as means of effectively labeling such devices and permitting rapid and reliable identification of the wearer. Previous studies have suggested that patients will accept denture labeling and recognize the need for such systems. However, they demand systems that are aesthetic, durable, and secure. One concern over the use of RFID-tags is that they could be scanned by third parties without the patient's knowledge. This study categorizes the scanning patterns of RFID-tags both in vitro and in vivo to provide data for patients for the consent process and for forensic dentists to ensure that they are scanning prostheses optimally. The results demonstrate that the RFID chips can only be read when the interrogator is in close proximity to the denture and thus should alleviate any concerns over privacy issues. However, evidence obtained from both the literature and experiments suggests that authorities must agree upon a unified standard for chip and reader specifications and protocols in order to avoid cases in which RFID-tags may fail to be read by an incompatible reader.     

Yet another method for marking incisal edges of teeth for bitemark analysis

Over the years many methods have been proposed and presented for marking or "highlighting" the incisal edges of anterior teeth on a dental stone model -- one of the critical steps in production of transparent overlays for bitemark analysis. A method is presented here that is an extension and refinement of the "paint the edges" method shown at least as early as 1966 by Gustafson. This method uses "invisible ink" and ultraviolet illumination to produce a very high contrast image of the incisal edges of the teeth on the model. The advantages of this new method are that it is nondestructive, it does not leave visible marks on the models, operator subjectivity in selecting the portions of anterior teeth to be highlighted is reduced, and the author submits that this technique lends itself to easy construction of overlays using computer image-processing software such as Adobe Photoshop and ImageJ.     

Field capability of dogs to locate individual human teeth

Avulsed teeth can be difficult if not impossible to recover in the outdoor environment, yet are important for victim identification. This study assessed dog teams as a resource to locate human teeth in a field setting and related performance in training with field capability. Standardized, objective training data were recorded and analyzed followed by double-blind capability trials. In the double-blind trials, 10 teeth were placed in each of six (10 m(2)) plots. Search time per plot ranged from 27 to 50 min, and the proportion of teeth found by the teams varied between 0.20 and 0.79. Using 0.45 m as a distance criterion for a "find," the proportion of false positives ranged between 0.07 and 0.75. Results show that dog teams are capable of recovering individual human teeth in the field setting with high precision although capability varies. Training records support a team's expected field performance. Additional studies are needed.     

DNA分析与种属鉴定

种属鉴定在法医学实践中占有重要地位。现行用于法医学种属鉴定的方法主要有形态学、血清学和DNA分析技术。本文就种属鉴定的技术发展以及各种技术的优缺点做一比较,重点讨论了DNA分析技术在种属鉴定中的应用价值。     

侦查机关内设鉴定机构的负面影响与消解

侦查活动的特殊性使其染指于司法鉴定,侦查机关基于侦查工作之必要内设鉴定机构。侦查机关内设的鉴定机构又因侦查的追诉性质在鉴定活动中难以保持中立性,致使侦查机关的鉴定机构的性质与法律的中立性要求出现一些紧张关系,在诉讼中造成了一些负面影响。司法鉴定制度的改革旨在借助司法行政部门对司法鉴定的统一管理来催生侦查机关的鉴定机构和侦查活动相分离,从而保持侦查机关的鉴定机构具有相对的独立性,并通过制度调整后的外在监督力量与程序的制约机制来缓解这一紧张关系,以促进侦查机关的鉴定机构在诉讼中真正发挥发现事实真相的作用。