Sex estimation by the patterns of lip impressions (cheiloscopy)

Abstract

Aim: To determine whether there is sexual dimorphism of lip prints’ morphological features in the Croatian population and to provide a scoping review for the accuracy of sex estimation on lip prints. Methods: The study on the Croatian population included 88 male and 88 female (median age 25, range 18 - 50) participants. Lip prints were analyzed by quadrant, and then the predominant pattern on the entire lip was observed. A systematic search of the relevant bibliographical databases was conducted, including Medline, Scopus, Web of Science Core Collection (WoSCC), and Cinahl (October 23rd, 2020). OpenGrey, Open Science Framework, and Science.gov databases were searched for grey literature. Findings were reported in the narrative form in accordance with the PRISMA Extension for Scoping Reviews (PRISMA-ScR) checklist. A total of 80 studies were included. Results: The study of sexual dimorphism of lip prints in the Croatian population showed that there were no statistically significant differences between males and females; and when all quadrants were considered together (χ2 = 3.625, P = 0.459), sex could be estimated for only 55.7% of persons. Twenty-nine studies (36.3%) did not find differences between males and females, and 34 (42.5%) found sexual dimorphism only in some of the lip parts and some quadrants. The assessment of examined studies showed that only six studies met all quality criteria. Conclusion: There is no forensically significant sexual dimorphism in lip prints in the Croatian population. The scoping review showed that sex estimation using lip prints should not be used as evidence in court as the present methodology is not reliable and the potential rate of error is unknown.

Potential and Limits of the Synergy Between Cheiloscopy and Rugoscopy in Forensic Odontology

“…Unlike in rugoscopy, where the methods used are analogue, with alginate impressions, and digital, with the aid of intraoral scanners, in cheiloscopy we can photograph the subject's lips directly, use a non-porous surface (e.g., a mirror) to photograph latent impressions, apply lipstick or other transfer medium and press the lips onto paper or adhesive tape, press the lips onto a suitable surface and develop impressions with fingerprint powder or magnetic powder [27,28]. There is an incalculable margin of error that derives from the methodology chosen [29], both with regard to the different materials that can be used [30], and the difficulty of taking impressions that present all the lip lines intact, without smears and easily readable [31]. Furthermore, the operator-dependent error derived from the analysis of the impressions themselves must also be taken into account [32].…”