Comparison of Three Methods for Lip Print Analysis: Lipstick, Latent, and Digital Photography for Sex Determination and Permanency Assessment Over Time

ABSTRACT Background: Lip print analysis, also known as cheiloscopy, is a valuable tool in forensic science for personal identification and sex determination. Methods: A total of 116 individuals (58 males and 58 females) were enrolled in this study. Lip prints were obtained using three methods: lipstick application, latent print development, and digital photography. The obtained lip prints were analyzed for accuracy, sex-specific variations, and stability over a 6-month period. Results: Lip print patterns exhibited significant differences between males and females across all three methods. The lipstick method demonstrated consistent and identifiable lip print patterns, with 25 males (43.1) and 39 females (67.2) displaying pattern 1. In contrast, the latent method showed less consistent results, with lip print pattern 1 observed in 25 males (43.1) and 28 females (48.3). Digital photography emerged as a promising alternative, offering detailed documentation capabilities, with pattern 1 observed in 30 males (51.7) and 37 females (63.8). However, no statistically significant association was found between lip print patterns and sex in the latent and digital methods. A longitudinal assessment revealed variations in lip print patterns over time, with some individuals showing changes in pattern distribution. Conclusion: These findings underscore the utility of lip print analysis in forensic science and emphasize the need for further research to enhance the interpretation of lip print evidence. Keywords: Cheiloscopy, digital photography, forensic science, latent method, lip print analysis, lipstick method, longitudinal assessment, sex determination, stability