Vol 33, No 2 December 2015
John Berketa, Helen James, Neil Langlois, Lindsay Richards
Purpose: The aim of this exercise was to simulate a disaster victim identification scenario to allow training in documentation of postmortem incinerated remains and reconciliation of dental data,
Method: Varying number of restorations were placed in ten pig heads. The teeth and restorations were charted, with the restorations radiographed and documented, creating an ante-mortem data set. The following day the heads were cremated. Following cooling and recording they were transported for a post-mortem examination by trained specialist odontologists who were not involved in the initial antemortem phase. Recordings included the charting of teeth, restorations, lost teeth, and radiographs to simulate a post-mortem examination. A reconciliation of postmortem to antemortem information was attempted.
Results: There was an unacceptable amount of error in the postmortem examination of the heads. The errors related mainly to avulsed teeth and incorrect opinion of which charted surfaces the restorations were placed upon. Also noted were a considerable number of root fractures occurring beneath the crestal bone. This observation does not mimic the evidence observed in human incinerated teeth where the crowns tend to fracture off the roots at the dentin-enamel junction.
Conclusion: The use of incinerated pig (Sus Scrofa) heads is not an ideal model for forensic odontology training in disaster victim identification. Differences in both anatomy and behavior following exposure to heat were shown to hamper documentation and subsequent comparison to antemortem data.
(J Forensic Odontostomatol 2015;33;2:1-8)
The dental pattern is defined as the combination of distinct codes assigned to describe specific tooth conditions including virgin, missing, and restored teeth that comprise the complete dentition or from discrete groups of teeth. This pattern can be then compared to the dentition of individual/s in an attempt to determine positive identification. The aims of the present investigation were to study and determine the diversity of dental patterns in Peruvian citizens based on a sample of panoramic radiographs. Digital panoramic radiographs of 900 adult Peruvian patients (450 female and 450 male) were evaluated to determine the dental patterns. The most frequent dental patterns found in the complete dentition, maxillae, upper-anterior and lower-anterior sextants were all-virgin-teeth (0.3%), all-extracted teeth (1.9%), all-virgin teeth (1%) and all-virgin-teeth (34.2% and 72.3%) respectively. The diversity was calculated by the use of the Simpson´s diversity index, the resulting values for the full-dentition, maxilla and mandible were over the 99.8% value and were similar to those previously reported in the scientific literature. This study demonstrates the positive benefit of dental patterns in the process of identification. Additionally a combination of codes is proposed that could prove useful in cases where a better radiographic description is required.
(J Forensic Odontostomatol 2015;33;2:9-17)
J. Sunitha, R. Ananthalakshmi, Sathiya Jeeva, Nadeem Jeddy, Dhanarathnam Shanmugam
Background: Anthropometric measurement is essential for identification of both victims and suspects. Often, this data is not readily available in a crime scene situation. The availability of one data set should help in predicting the other.
This study was hypothesised on the basis of a correlation and geometry between the tooth length and various body measurements.
Aim and objective: To correlate face, palm, foot and stature measurements with tooth length. To derive a regression formula to estimate the various measurements from tooth length.
Materials and methods: The present study was conducted on Dravidian dental students in the age group 18 – 25 with a sample size of 372. All of the dental and physical parameters were measured using standard anthropometric equipments and techniques.
Results: The data was analysed using SPSS software and the methods used for statistical analysis were linear regression analysis and Pearson correlation. The parameters (incisor height (IH), face height (FH), palm length (PL), foot length (FL) and stature (S) showed nil to mild correlation (R = 0.2 ≤ 0.4) except for palm length (PL) and foot length (FL). (R>0.6).
Conclusion: It is concluded that odontometric data is not a reliable source for estimating the face height (FH), palm length (PL), foot length (FL) and stature (S).
(J Forensic Odontostomatol 2015;33;2:18-25)
Bassant Mowafey, Elke Van de Casteele, Jilan M Youssef, Ahmed R Zaher, Hany Omar, Constantinus Politis, Reinhilde Jacobs
Objectives: This study aimed to identify whether the lingual canals of the mandible can be used as a unique fingerprint when dealing with forensic victim identification.
Materials and Methods: The study consisted of two parts; an observational part and an objective image analysis part. In the observational part a total of 100 in vivo high resolution CBCT datasets of human mandibles were included in the process of simulated matching of ante-mortem (AM) and post-mortem (PM) data. For the objective image analysis part 10 dry human mandibles were scanned with 2 different Cone Beam Computed tomography (CBCT) machines. In the observational part of the study trained observers attempted to correctly identify matching pairs of images taken from the same mandible out of a series of 100 mandibles. The aim was to simulate matching of the neurovascular structures on AM and PM mandibular midline images and determine the percentage of mandibles identified correctly. In the objective image analysis part, simulated matching was carried out using a specific CBCT dataset acquired to mimic a PM dataset and 10 datasets acquired from a different CBCT device which served as the source of potential AM cases. Comparison between AM and PM datasets resulted in the matching of the AM data and PM data obtained from the same mandible, leading to an assumed correct identification.
Results: The observational part of the study showed an average 95% correct identification of the mandibular midline neurovascular structures. Registration of mandibles resulted in perfect overlap of the same mandible from 2 different CBCT machine with an error distance equalling zero, while the registration of different mandibles deviated on average error distance 0.13mm to 0.18mm.
Conclusion: The percentage of fit for the simulated AM and PM data of the same mandible was 100%. This finding together with the significant deviations noted for the non-matching cases, may have a potential role in forensic identification in the same way that fingerprints are recognised as being a unique identifying feature.
(J Forensic Odontostomatol 2015;33;2:26-35)