LAUSR

Aim: In developing countries DNA analysis techniques might be a slightly expensive forensic tool so the use of Barr body for gender determination could be a more economic method. The aim of this study is to evaluate the effect of exposure to variable degrees and durations of heat on dental pulp Barr bodies identification in human females. Materials and Methods: 130 premolars were divided equally into control and 12 study groups. The study groups were heated to different temperature degrees (100° c, 200° c and 300° c) for duration intervals (5, 15, 30 and 60 minutes), then the Barr body was examined in the pulp tissues using light microscope. Results: There was a significant decrease in the percentage of positive Barr body cells at 100°c, except in 5 and 15 minutes, and at 200° c groups except in 5min. Interestingly, at 200°c, Barr bodies could be identified only at 5 minutes duration. At 300°C, the pulp tissue could not be retrieved. Also, there was a significant negative correlation between the degree of heat exposure and the percentage of positive Barr body cells in the dental pulp (r = −0.73, P = < 0.001) and between the duration of exposure at each degree (100° c and 200° c) and the percentage of positive Barr body cells (r = −0.90, P = < 0.001) in 100 °c groups and in 200°c groups (r = −0.76, P = <0.001). Conclusion: Dental Barr bodies can be useful for gender determination up to 200°C at the time period of 5 min in vitro.