LIP PRINTS

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.

DISADVANTAGE

• 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

Forensic Odontology defined by the Federation Dentaire International (FDI) as ‘that branch of dentistry which, in the interest of justice, deals with the proper handling and examination of dental evidence, and with the proper evaluation and presentation of dental findings’.

Scope of Forensic Odontology

• Record preparation—the correct handling and exami- nation and the proper preparation and presentation of dental evidence in both civil and criminal legal procedures.

• Identification—personal identification, either individually or in context of mass disasters.

• Age assessment—to calculate the age of patient.
• Bite mark investigation—investigation of criminal cases where bite marks are involved and the interpretation of

• Humanabuse—recognitionofdomestic,andchildabuse.

• Lipprint—comparisonandidentificationoflipprint.

• Legalaspect—legalaspectofdentaltraumatology.

A vital role the forensic dentist plays is in criminal investigation.

• Crime investigation includes the investigation of 

• BITE MARKS
• LIP PRINTS
• CHILD ABUSE

BITE MARKS

McDonald (1974) has defined bitemark as “a mark caused by the teeth either alone or in combination with other mouth parts”.

Bite marks may be caused by humans or animals; they may be on tissue, food items, or other objects. 

CLASSIFICATION OF BITE MARKS

Cameron and Sims classification

1. Depending on biting agent

a. Human : Children, Adults

b. Animals : Mammals, Reptiles, Fish

c. Mechanical : Full denture, belt marks etc

2. Depending on material bitten 

a. Skin : Human, Animal

b.  Perishable items : Food items like cheese,  apple etc.

c. Non- perishable items : Unanimated objects such as pipes, pens, pencils.

WEBSTER’S CLASSIFICATION

Type I – food item fractures readily with limited depth of tooth penetration e.g. hard chocolate.

Type II – food item fractures with considerable penetration of teeth e.g. bite marks in apple & firm fruits.
Type III – Complete or near complete penetration of the food item with slide marks e.g cheese

FACTORS AFFECTING BITE MARK INJURIES

• Inherent skin factor
• Age
• Sex
• Time
• Vascularity

CHARACTERISITCS OF HUMAN BITE MARK FOR IDENTIFICATION

• Human bite mark characteristics include an elliptical or ovoid pattern containing tooth and arch marks.
• Simplest form of a bite mark consists of tooth marks produced by antagonistic teeth.
• An arch mark may indicate the presence of 4 to 5 teeth marks reflecting the shape of their incisal or occlusal surfaces.

• Class features: differentiate between tooth type

• Incisors- rectangular
• Canines- triangular
• Premolars + molars – spherical/point shaped
• Depends on attrition

• Other significant findings to identify a bite mark to give the identify of the suspect are :

• Presence or absence of each tooth
• Peculiar shape of each tooth
• Mesiodistal dimensions
• Arch form and size
• Relationship between the upper and the lower jaws
• Any unusual features, such as rotation, fractured teeth, supernumerary teeth, microdontia, diastema etc.  

BITE MARK INVESTIGATION

• The guidelines for bite marks analysis are given by American Board of Forensic Odontology (ABFO) and careful use of these helps in enhancing the quality of the investigation and conclusions. The collection of evidence regarding the bite marks falls in following categories :

1. Description of the bite marks

1. Demographic data
2. Location of bite marks
3. Shape Color
4. Type of injury (Abrasion, Ecchymosis, Laceration, Petechial hemorrhage and Incision) 

2. Collection of evidence from victim

3. Collection of evidence from suspect

REFERENCE- SHAFER’S TEXTBOOK OF ORAL PATHOLOGY AND SLIDE SHARE