Perbedaan Akurasi Metode Overlay Cetakan Malam, Xerografi, dan Berbasis Komputer untuk Analisis Bekas Gigitan (Bite Mark) Manusia pada Apel di Bidang Odontologi Forensik

Abstract

The analysis of human bite marks is a crucial aspect of forensic odontology, particularly in criminal investigations. Bite marks can provide valuable information regarding the identity of perpetrators or the events that occurred. One commonly used approach is the overlay method, which includes techniques such as wax impressions, xerography, and computer-based methods. Bite marks can be found on various objects, one of which is an apple, which is readily available, inexpensive, and able to clearly record bite marks, making it an ideal medium for forensic research. Although these methods are widely applied, differences in accuracy between them and the impact of the assessors' backgrounds on the analysis results have not been extensively studied. Aims: This study aims to compare the accuracy of three overlay methods and evaluate the impact of the assessors' backgrounds on the analysis of bite marks on apples. Methods: This research utilized a quasi-experimental design with a single-blind study approach. A total of 10 subjects were instructed to bite Fuji apples until the bitten portion detached, leaving bite marks on the apple surface. These bite marks were then cast using alginate impression material, and study models were created using Type III dental stone. The study models were analyzed using three overlay methods (wax impressions, xerography, and computer-based methods). Evaluations were conducted by two assessors: Assessor 1 (a student with a background in forensic odontology) and Assessor 2 (without a background in forensic odontology). Data were analyzed using SPSS 22 software with the Kruskal-Wallis and Chi-Square tests to compare the accuracy between methods and the distribution of accuracy categories between the two assessors. Results: For the wax impression method, Assessor 1's results were primarily in category 2 (65%) and category 1 (25%), while Assessor 2's results were mostly in category 0 (65%) and category 1 (35%). For the xerography method, Assessor 1's results were predominantly in category 2 (65%) and category 3 (25%), while Assessor 2's results were mainly in category 0 (45%) and category 1 (30%). The computer-based method showed the highest accuracy for Assessor 1, with the majority of results falling into category 2 (50%) and category 3 (45%). For Assessor 2, the highest results were in category 2 (45%) and category 0 (35%). Significant differences were found in the lower jaw for all overlay methods, whereas in the upper jaw, only the wax impression method showed significant differences. Conclusion: There are significant differences in accuracy between the overlay methods of wax impressions, xerography, and computer-based techniques between Assessor 1 and Assessor 2. The computer-based method demonstrates the greatest potential for providing accurate bite mark.