Exploring Bite Marks on Different Types of Skin Tones

The analysis of bite marks is a challenging and convoluted part of Forensic Odontology. Various interrelated factors such as location of the bite and skin elasticity complicate the bite mark analysis. The relationship between the bite mark and the biochemical properties of skin has been well-documented but there is need to consider the variety of skin tones as a factor to explore. The aim of this pilot study was to analyse the appearance of bite marks on 5 different types of skin tones of 15 subjects (6 males and 9 females) from 11 nationalities and age ranged from 21 to 46 years. A pair of 3D printed dental cast was transferred onto a mechanical apparatus for production of experimental bitemarks by using 12.5 kg of weight. Common imaging modalities including conventional, infrared and ultraviolet light were used to record the bite mark images for following visual assessment. The different skin tones were categorized using Fitzpatrick scale (1975) and a colour chart was used to compare the changes on skin after 15 minutes of bite registration. According to the results, the force was well tolerated by the subjects producing a well-defined bite mark, although males showed a less prominent mark than females irrespective of the skin tone and nationality. Neither bruises nor significant changes in the colour of bite mark could be appreciated among the subjects. The different types of skin tones did not affect the registration of bite mark applying a force of 122.5.N for 15 seconds in this sample.