A quantitative method for comparing human dentition with tooth marks using three-dimensional technology and geometric morphometric analysis

Evaluation of Bitemark Analysis's Potential Application in Forensic Identification: A Systematic Review

Bitemark analysis involves the examination of both patterned injuries and contextual circumstances, combining morphological and positional data. Considering the uniqueness of human dentition, bitemarks caused by teeth on skin or impressions on flexible surfaces could assist in human identification.

AIMS

to investigate the available literature systematically and evaluate the scientific evidence published over the past decade concerning the potential application of bitemark analysis in forensic identification.

METHODS

Two researchers meticulously searched electronic databases from January 2012 to December 2023, including Scopus, PubMed, Web of Science, and the Cochrane Library. Adhering to the PRISMA statement guidelines, this review employed appropriate medical subject headings (MeSHs) and free-text synonyms. Strict inclusion and exclusion criteria were applied during article retrieval.

RESULTS

The findings yielded controversial outcomes. Approximately two-thirds of the articles concluded that bitemark analysis is useful in forensic identification, while the remaining articles did not report statistically significant outcomes and cautioned against relying solely on bitemark analysis for identification.

CONCLUSIONS

The authors assert that bitemark analysis can be a reliable and complementary method for forensic identification, contingent upon the establishment and adoption of a universally accepted global protocol for data collection, processing, and interpretation. Undoubtedly, recent years have witnessed a notable increase in research focused on bitemark identification, driven by the goal of achieving quantitative, objective, reproducible, and accurate results.

A systematic review of 3D scanners and computer assisted analyzes of bite marks: searching for improved analysis methods during the Covid-19 pandemic

The global Covid-19 pandemic has forced forensic dentists to improve infection control methods. This search investigated the practical utilization of different 3D scanners to record and to analyze bite marks in the skin- and inanimate objects with this aim in mind. A systematic review of the literature using keywords like "human bite mark", "bite mark analyzes", "3D analyzes", "3D scanning", "forensic odontology", and "forensic dentistry" was performed in three scientific databases: MEDLINEOvid®, Pubmed® and Google Scholar. The initial search yielded 263 full-text articles, of which 15 were considered eligible and current within the last 10 years. 3D scanners and computer-assisted human bite mark analyzes showed potential advantages and can be effectively used in forensic odontology on skin and inanimate objects. These technologies minimize the number of people being exposed to pathogens, simplify the chain of evidence, facilitate immediate information exchange between the team members and enable the virtual presentation of the expert witnesses in a court of law.

A comparative assessment of bite marks in analyzing the overlay generation using styrofoam sheet and modeling wax with the dental casts as one of the adjuncts for archiving the forensic records: An in vivo study

Introduction:

Bite mark evidence is unique to an individual and plays an important role in the legal system. There has always been the need to develop newer materials for bite mark analysis that will have excellent reproducibility as well as reliability.

Aim:

The present study aimed to evaluate the efficacy of styrofoam sheets and modeling wax with time-dependent changes when compared to the routine dental cast models.

Materials and Methods:

The present study included thirty volunteers and their bite marks were taken on the styrofoam and wax sheet materials that were traced on the transparent sheet and evaluation of the bite marks on the two materials were carried out at an interval of 1 day for 3 alternate days and grades were given, respectively. ANOVA test and t-test were used for statistical analysis.

Results:

The comparison between the styrofoam sheet and wax sheet with the dental cast on day 1 proved to be excellent materials for reproducibility, but from day 3 onward, the styrofoam sheet showed changes in bite registered area; whereas wax sheet maintained its registered dimensions.

Conclusion:

The study concludes that bite mark registration on styrofoam and wax sheet had excellent reproducibility on day 1, which makes these two materials advantageous in bite mark registration and overlay generation on the same day, whereas on day 3 and day 5, the styrofoam sheet showed changes with respect to bite registration and overlay generation, which questions the reliability of the styrofoam sheet for long-term record keeping when compared with the modeling wax.

Uniqueness of the anterior dentition three-dimensionally assessed for forensic bitemark analysis

The uniqueness of the human dentition (UHD) is an important concept in the comparative process in bitemark analysis. During this analysis, the incisal edges of the suspects' teeth are matched with the bitemarks collected from the victim's body or crime scenes. Despite playing an essential part to exclude suspects, the UHD contained in the involved incisal tooth edges remains an assumption on bitemark level. The present study was aimed, first, to investigate three-dimensionally (3D) the UHD within different quantities of dental material from the incisal edges; second, to test these outcomes in a bidimensional (2D) simulation. Four-hundred forty-five dental casts were collected to compose 4 study groups: I - randomly-selected subjects, II - orthodontically treated subjects, III - twins and IV - orthodontically treated twins. Additionally, 20 dental casts were included to create threshold groups on subjects from whom the dental impressions were taken at 2 different moments (Group V). All the dental casts were digitalized with an automated motion device (XCAD 3D^® (XCADCAM Technology^®, São Paulo, SP, Brazil). The digital cast files (DCF) were integrated in Geomagic Studio^® (3D Systems^®, Rock Hill, SC, USA) software package (GS) for cropping, automated superimposition and pair-wise comparisons. All the DCF were cropped remaining 3 mm (part 1), 2 mm (part 2) and 1 mm (part 3) from the incisal edges of the anterior teeth. For a 2D validation, slices of 1 mm, not including incisal edges (part 4), were also cropped. These procedures were repeated in Group V, creating specific thresholds for each of the study parts. The 4 study groups were compared with its respective threshold using ANOVA test with statistical significance of 5%. Groups I, II and III did not differ from the corresponding threshold (Group V) in all study parts (p > 0.05). Scientific evidence to support the UHD was not observed in the current study. Bitemark analysis should not be disregarded but considered carefully when the suspects present similar dental alignment and morphology, such as in orthodontically treated subjects and twins, respectively.

The uniqueness of the human dentition as forensic evidence: a systematic review on the technological methodology

The uniqueness of human dentition is routinely approached as identification evidence in forensic odontology. Specifically in bitemark and human identification cases, positive identifications are obtained under the hypothesis that two individuals do not have the same dental features. The present study compiles methodological information from articles on the uniqueness of human dentition to support investigations into the mentioned hypothesis. In April 2014, three electronic library databases (SciELO®, MEDLINE®/PubMed®, and LILACS®) were systematically searched. In parallel, reference lists of relevant studies were also screened. From the obtained articles (n = 1235), 13 full-text articles were considered eligible. They were examined according to the studied parameters: the sample size, the number of examined teeth, the registration technique for data collection, the methods for data analysis, and the study outcomes. Six combinations of studied data were detected: (1) dental shape, size, angulation, and position (n = 1); (2) dental shape, size, and angulation (n = 4); (3) dental shape and size (n = 5); (4) dental angulation and position (n = 2); (5) dental shape and angulation (n = 1); and (6) dental shape (n = 1). The sample size ranged between 10 and 1099 human dentitions. Ten articles examined the six anterior teeth, while three articles examined more teeth. Four articles exclusively addressed three-dimensional (3D) data registration, while six articles used two-dimensional (2D) imaging. In three articles, both imaging registrations were combined. Most articles (n = 9) explored the data using landmark placement. The other articles (n = 4) comprised digital comparison of superimposed dental contours. Although there were large methodological variations within the investigated articles, the uniqueness of human dentition remains unproved.