The wrinkles and grooves visible on the lips have been named by Tsuchihashi as ‘sulci labiorum rubrorum’. The imprint produced by these grooves is termed as ‘lip print’, the examination of which is referred to as ‘cheiloscopy’.
Tsuchihashi proposed a classification dividing the pattern of grooves into six types:
Type I: Clear-cut vertical grooves that run across the entire lip
Type I’: Similar to type I, but do not cover the entire lip Type II: Branched grooves
Type III: Intersected grooves
Type IV: Reticular grooves
Type V: Grooves that cannot be morphologically differentiated.
- A combination of these grooves may be found in any given set of lips.
- To simplify recording, the lips are divided into quadrants similar to the dentition- a horizontal line dividing the upper and lower lip and a vertical line and a vertical dividing right and left sides. By noting the type of groove in each quadrants, the individual’s lip print pattern may be recorded. Thus classification, thus, enabled differentiation of lip print patterns between any two individuals.
- Lip prints are usually left at crime scenes, and can provide a direct link to the suspect.
- Although invisible, these prints can be lifted using materials such as aluminium powder and magnetic powder.
- Ball states that the vermillion border has minor salivary glands, and the edges of the lips has sebaceous glands, with sweat glands in between.
- One may therefore, assume that secretions of oils and moisture from these enable development of ‘latent’ lip prints, analogous to latent fingerprints, in most crime scenes where close contact between the victims and culprit has occurred.
- A major disadvantage of lip print investigation pertains to uncertainty about the permanence of lip patterns. While they are believed to remain unchanged throughout one’s life,
- Sivapathasundharam B and coworkers doubted this, as major trauma to the lips resulting in scarring, pathosis, surgical treatment rendered to correct the pathosis, affect the size and shape of the lip, thereby may alter the pattern and morphology of the grooves.
REFERENCE-SHAFER’S TEXTBOOK OF ORAL PATHOLOGY 8TH EDITION