Forensic Dentistry Case Study

Introduction:

Forensic dentistry is defined by Keiser-Neilson in 1970 1 as “that branch of forensic medicine which in the interest of justice deals with the proper handling and examination of dental evidence and with the proper evaluation and presentation of the dental findings”. It is application of dental knowledge which helps in legal proceedings. It has an important role in establishing the gender of victims whose bodies are mutilated beyond recognition due to major mass disasters. In the field of forensics experts utilize skeletal remains, features of teeth such as morphology, crown size, root lengths etc. for establishing gender.2 Forensic dentists have a major role in investigations for the identification of people in mass disasters,

To evaluate the birefringence pattern of collagen fibers in post-mortem oral tissues using Picrosirius red and polarized light microscopy.

2. To assess the distribution of thick and thin fibers and compare between males and females.

Materials and methods:

This study was conducted on Labial mucosal tissues of deceased individuals, collected from Department of Forensic Medicine, District Hospital, Tumkur. Informed consent was obtained from the legal representative of deceased individual. The study group included 30 cases, which comprised of 18 males and 12 females. Labial mucosal tissues were obtained within 12 hours of death, which were later fixed in 10% formalin at 12th hour and were processed routinely. Each case was given a code so that the observer is blinded to the gender identification of the

After deparaffinization and rehydration, the sections were incubated in 0.1% (w/v) Sirius red F3BA (C.I.35780) in saturated picric acid solution for 1 hr at room temperature; sections were then rinsed with distilled water followed by staining with Weigert’s haematoxylin. Differentiation was done in 1% HCl, followed by alkalization with tap water. The sections were then dehydrated and mounted in DPX.9,10

To evaluate birefringence pattern of collagen fibers, the sections were examined under 40x magnification using Olympus polarized light microscope (BX43) along with image analysis system software (ProgRes, Speed XT core3). Randomly 100 fibers were examined in each tissue sample and were segregated into thick (1.6-2.4 µm) and thin fibers (0.8µm or less). The obtained score were tabulated and the statistical analysis was done using “Z” test to compare the proportion of thick and thin fibers among males and females. One-way ANOVA was used to determine the difference in birefringency pattern of collagen fibers.