Bite Mark Analysis

Question. Write a short note on Bite marks.

Answer. Bite marks are defined as “A mark caused by the teeth either alone or in combination with other mouth parts”.                                                                                                                                                    -MacDonald.

Classification of Bite Marks

MacDonald’s Classification

“Understanding the role of bite mark analysis in forensic science: Q&A explained”

He had given an etiological classification

• Tooth pressure marks: Marks on tissue due to ‘direct application of pressure by teeth’. Incisal and occlusal surfaces
  produce these marks.
• Tongue pressure marks: If a suffient amount of tissue is taken in the mouth tongue presses the tissue against rigid areas, i.e. lingual surface of teeth as well as the palatal rugae. Marks left over skin are called suckling.
• Tooth scrape marks: They occur due to the scraping of teeth over brittle material. They are caused by anterior teeth

“Importance of studying bite mark analysis for better forensic outcomes: Questions explained”

Importance Of Bite Marks

• They provide accurate identification since the alignment of teeth is specific to each individual.
• Bite marks are contaminated by saliva and consist of amylin, ptyalin, and blood group, which help in the determination of individuals in criminal cases.

Bite Mark Collection

Collection of Bite Marks from the Victim

Various methods are:

• Case demographics: All the information related to the case is selected, such as name, age, address, etc.
• Visual examination: Visually examine the shape, size, color, contour, texture, and other features of bite marks and document all of them.
• Photography: Photographs should be taken as quickly as possible. They provide a permanent record of bite marks.
• Impressions: Impressions of the bittern area are made by vinyl polysiloxane.
• Saliva swab: Saliva acts as a source of DNA. It should be collected carefully and preserved to match the DNA with the suspect.

Collection of Bite Marks from Suspect

• Photographs of the suspect’s teeth should be taken.
• Impressions of the maxillary and mandibular arches should be taken.
• Saliva swabs from the buccal vestibule should be taken.

Bite Marks Analysis

“Common challenges in performing bite mark analysis effectively: FAQs provided”

It is done by:

• Metric analysis in conjunction with pattern association.
• Direct method: In which the suspect’s models are directly placed over the bite mark.
• Indirect method: Incisal and occlusal edges of the suspect’s teeth are traced on clear acetate and superimposed on bite mark photographs.
• Adobe Photoshop software.
• 3D/CAD-supported photogrammetry.

“Steps to explain the process of bite mark analysis: Collection vs comparison: Q&A guide”

Conclusion of bite mark analysis

• Definite biter: Presence of reasonable medical certainty that indicates that the bite mark was produced by the suspect’s dentition.
• Probable biter: There is some degree of specificity in to suspect’s teeth by a sufficient number of matching points.
• Possible biter: Suspect’s teeth could make the bite mark, and there are no characteristic matches for certainty. Similarity
  of class characteristics is seen.
• Not the biter: Bite marks and the suspect’s dentition are not consistent.