An examination of the psychological aspects of bite marks

The intent of this paper is to present some psychological threads which appear to be operative for the perpetrator of bite marks. In the catalogue of multiple motivations, there appears to be a current theme of power, control, potency, and the attempt to have a psychological symbolization of the perpetrator's omniscient capacity for absorbing life essences. In an examination of these highly complex needs, the modern perpetrator appears to act out consistently with cultural biases coupled with immediate psychological needs which have pressed for expression. Due to a pattern of psychologically expressed ritualism, the perpetrator will often inadvertently leave important psychological clues at the crime scene. The attack style, mode of death, characteristics of the victim, etc.--these components reveal the information on the type of psychological needs that the perpetrator is trying to satisfy. In the cases of bite marks associated with violent crime, it becomes crucial to an "investigator" what type of personality characteristics are welded together to form this kind of need complex. After reviewing cases reported in the literature and after conducting psychological interviews with perpetrators, three major groups of perpetrators seem to be apparent. The first group is motivated out of an anger track, the second group is motivated out of sadistic biting, and the third is out of the more traditional "cannibal complex" motif.     

An integrated technique for the analysis of skin bite marks

The high number of murder, rape, and child abuse cases in South Africa has led to increased numbers of bite mark cases being heard in high courts. Objective analysis to match perpetrators to bite marks at crime scenes must be able to withstand vigorous cross-examination to be of value in conviction of perpetrators. An analysis technique is described in four stages, namely determination of the mark to be a human bite mark, pattern association analysis, metric analysis and comparison with the population data, and illustrated by a real case study. New and accepted techniques are combined to determine the likelihood ratio of guilt expressed as one of a range of conclusions described in the paper. Each stage of the analysis adds to the confirmation (or rejection) of concordance between the dental features present on the victim and the dentition of the suspect. The results illustrate identification to a high degree of certainty.     

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.     

Lingual markings of anterior teeth as seen in human bite marks

A review of the available literature does not reveal a plausible explanation as to why the incisal edges of maxillary anterior teeth do not always mark clearly. Generally, the mandibular incisal edges do mark with some consistency. This paper demonstrates through test bites on skin that the answer lies in the position of the mandible.     

A suggested classification of bite marks in foodstuffs in forensic dental analysis

Bite marks have been reported in flesh, foodstuffs and inanimate objects. Those in foodstuffs occur widely in cases of larceny but also occur in serious crimes such as murder.Evaluation of distinctive characteristics in food bites differs from the corresponding assessment of flesh bite marks in that the assessment is made on the impression made by the labial aspect of the teeth and not on the biting edge, because the teeth penetrate the bitten foods to different depths.The terminology used to describe food bite marks is very varied and a classification of food bites has been formulated in an effort to bring a degree of uniformity to the analysis of such marks.     

Incidence of bite marks in a selected juvenile population: a preliminary report

A study of the frequency of bite marks among sheltered children was conducted for a period of three months in the juvenile care facilities in Las Vegas, NV. The study demonstrated an incidence of 1 545 bite marks per 100 000 population. Analysis of the age, sex, and location of bite marks is presented. The study demonstrated an incidence comparable to diseases such as gonorrhea.     

Measurement of arch widths in a human population: relation of anticipated bite marks

The authors compared arch width measurements of diagnostic dental models obtained from dental school patients. Arch width measurements were taken in the canine area on each dental cast in an effort to assist forensic dental investigators in matching certain classes of subjects to the bites they might possibly inflict. If any canine teeth were absent, the measurements were taken using other specified adjacent teeth which the investigators felt would be interpreted as the arch width determiners in a bite mark injury. The ages of the subjects varied from 14 to 87 years. Statistical comparison of the maxillary arch width, mandibular arch width, and the mean difference between maxillary and mandibular arch width were performed. Significant differences between the arch width measurements were found to exist between several classes of subjects based on race and sex.     

Not all bite marks are associated with abuse, sexual activities, or homicides: a case study of a self-inflicted bite mark

A case of self-inflicted bite mark during an episode of myocardial ischemia is presented. Using current bite mark identification techniques, the bite mark was shown to be self-inflicted. Self-biting may be an emotional response to pain or a type of counterirritation to alleviate pain. The recognition and documentation of this unusual case of a self-inflicted bite mark was due to the cooperation of the forensic pathologist and forensic odontologist.     

Is consent required to use registered trade marks on model replica cars?

A car manufacturer that is a proprietor of a trade mark registeredfor toys cannot prohibit use by a third party of its trade markon model replica cars unless such use affects the functionsof the trade mark or takes unfair advantage of, or is detrimentalto, the distinctive character or repute of the mark.     

The detection of fingerprints and other marks in body fluids by the use of agar gels

Techniques are described whereby weak fingerprints in blood, semen and saliva on a variety of materials may be rapidly enhanced and photographed. The methods involve the use of flexible agar gels containing histochemical reagents for the development of prints made in these body fluids. The gels may be used on a variety of vertical, horizontal and irregular surfaces and in some cases could replace sprays and "fingerprint paints".     

内凹齿钥匙痕迹特征研究

目的运用光学仪器研究内凹齿钥匙痕迹形态特征。方法制作内凹齿钥匙正常开锁和被钥匙机复制后的样本,用光学显微镜拍照固定痕迹特征。结果内凹齿钥匙开锁痕迹特征明显,且被钥匙机复制后能留下复制痕迹。结论通过检验内凹齿钥匙上的痕迹特征能确定钥匙是否被复制过。     

A comparison of the ability of experts and non-experts to differentiate between adult and child human bite marks using receiver operating characteristic (ROC) analysis

Fifty colour prints of human bite marks were sent to 109 observers who were asked to decide using a six point rating scale, whether the marks had been produced by the teeth of an adult or a child. The observers consisted of accredited senior forensic dentists, accredited junior forensic dentists, general dental practitioners, final year dental students, police officers and social workers. The results were compared against a “gold standard” which was the actual verdict from the case. Comparison of the results between the groups of observers and the standard was made using Receiver Operating Characteristics (ROC) methodology. The best decisions were made by senior/junior experts or final year dental students. General dental practitioners and police officers were least able to differentiate correctly between adult and child bite marks. The effect of training is important and its effects need to be assessed in more detail in future studies.