Background: The interaction between the offender and the victim produces visible or latent prints on objects and utensils. The study of lip prints has reportedly stayed away from the basic cinematic concept of the lip-to-surface relationship.
Materials and methods: Three regular powders were used to reveal the latent lip prints on a typical metallic straw called bombilla, and the revealed prints were photographed, preserved, and analyzed.
Results: Better definition was observed in the lower lip print, and nine anatomical patterns were identified, but a higher definition of wrinkles was observed with indestructible white powder.
Conclusion: Knowledge of labial dynamics, the real value of the processed surfaces, and the need for testing in field conditions are discussed.
Keywords: Cheiloscopy; criminalistics; forensic odontology.