This document summarizes the potential applications of cone beam computed tomography (CBCT) in forensic science based on a review of clinical and scientific literature. CBCT can be used for age and sex estimation, frontal sinus analysis for identification, and 3D facial reconstruction. Studies show CBCT allows for more accurate age estimation compared to 2D radiographs. Measurements of bones like the mastoid and mandible from CBCT scans can determine sex with over 80% accuracy. Comparison of frontal sinus patterns through CBCT provides reliable evidence for identification. While CBCT has advantages like portability and accuracy, limitations include artifacts from metals and limited soft tissue contrast. Further research is still needed to improve 3D reconstruction techniques from CBCT data for forensic

1. Dr. Mathew Thomas Maliael
BDS

2. Contents-
 Introduction
 Aim and objectives
 Age estimation
 Sex determination
 Frontal sinus pattern as an aid in identification
 3D facial reconstruction from CBCT data
 Advantages
 Limitations
 Conclusion
 References

3. Introduction
 Computed tomography is revolutionary
imaging modality invented by Godfrey
Hounsfield in 1972.
 Cone beam computed tomography is a
modification of computed tomography
introduced into clinical practice in the 1990s.
 Cone beam computed tomography has
become a popular and frequently used
imaging modality.

4.  The principal feature of CBCT is
that multiple plane projections
are acquired by rotational scan
to produce a volumetric dataset
from which inter-relational
images can be generated
 In a single rotation the region of
interest is scanned by cone-
shaped x ray beam.

5.  Digitised information of objects in
the region of interest such as
shape and density is acquired
from multiple plane angle.
 The imaging data is then
processed by special imaging
software that reconstructs
topographic images of the region
of interest in multiple anatomic
planes.

6. Aim and Objectives
 This review highlights the importance and limitations of CBCT
application in field of forensic science by examining the
available evidence from clinical and scientific literature
pertaining to forensic dentistry.
 My paper will be limited to :-
1. Age estimation
2. Sex determination
3. Frontal sinus pattern as an aid in forensic identification
4. 3D Facial reconstruction

7. Age Estimation
 Estimation of age is important in forensic sciences as a way to
establish the identity of human remains.
 Of the various parts of the body used in age estimation, teeth
are the least affected by the taphonomic process. Their
durability means that they are sometimes the only body part
available for study.

8.  Generally 2D radiographs are used to assess the age but the
primary disadvantage of radiographs is that they are two-
dimensional projections which are subject to considerable
magnification and distortional errors.
 CBCT helps to overcome this disadvantage by permitting a
simultaneous assessment of the mesio-distal and bucco-
lingual dimensions of teeth.
 CBCT images can also be reformatted to conventional 2D
radiographic views.

9. The major disadvantages are:-
 CBCT images might be subject to artefacts due to the
presence of metallic restorations or implants.
 CBCT images are also susceptible to motion artefact.

10. REVIEW OF LITERATURE
 N. Jagannathan et al conducted a study on 140 individuals
(aged ten - 70 years). Cone beam computed tomography was
used to measure pulp and tooth volumes of the study group.
The age of the study group was estimated with a mean
absolute error that was found to be 8.54 years.

11.  Reformatted CBCT images can be used to
estimate age using the method proposed
by Kvaal et al. Studies conducted by Piyush
G. Limdiwala and J.S. Shah revealed that
the age could be assessed with an error of
8.3 years.
 Shi et al, in their study, concluded that
segmentation of individual vertebrae was
possible using CBCT volumetric datasets.
This helps in the visualization of cervical
vertebral morphology and holds potential
in skeletal age assessment.

12. Sex Determination
 Subsequent to drastic events such as natural disasters,
outbreak of wars or air traffic accidents, positive identification
of victim’s gender becomes, perhaps, the most difficult task
to encountered in forensics.
 Sexual dimorphism can be evaluated from anthropometric
measurements obtained from CBCT scan.
 Bone measurements varies in different population hence
further studies in different populations to further enhance the
ability of this method.

13. REVIEW OF LITERATURE
 Amin W et al conducted the Osteometric analysis of mastoids
on 192 Jordanian adults .
 The study identified four parameters that can be used to
determine sex accurately – IMD , MS , MMCA , ML.
 Based on the statistical analysis of these parameters the sex of
the subject was determined with an accuracy 90.6%.

15.  In another study conducted by Dilhan İlgüy et
al on 161 adults , the sex was determined
using craniometric measurements of the
foramen magnum and mandible obtained
from CBCT scans.
 The study determined that the gonial angle
(G-angle) , ramus length (Ramus-L), gonion–
gnathion length (G–G-L) , bigonial breadth
(BG-Br) and sagittal diameter of the foramen
magnum could be used as reliable predictors
of sex.
 The sexes of the subjects was determined
with an accuracy of 83.2%.

16. Frontal Sinus Pattern As An Aid In Identification
 Human identification is not a difficult task, when it is about a
live individual or a cadaver chronologically recent and intact.
However, when there is not a complete skeleton, but a group
of bones, the identification process becomes progressively
harder and sometimes impossible to be accomplished.
 The frontal sinuses can provide significant evidence for
forensic identification.

17.  The irregular forms of the frontal sinuses, initially observed in
anterior-posterior radiographs have been extensively studied
and it has been proven that there are not two people with the
same frontal sinuses, even being monozygotic twins.
 The comparison of frontal sinus images by cone-beam
computed tomography can be used as an additional method
in the identification process, providing the expert with a
greater reliability .

18. Some shortcomings can be listed
regarding this method:-
1. Subjectivity, dependence on the professional expertise .
2. Secondarily, the radiographic image can be significantly
changed according to the incidence of the X-rays beam

19. REVIEW OF LITERATURE
 A study conducted by Maria Priscilla David et al on a study
group of 50 individuals determined that the frontal sinus had
considerable individual variation and could serve as an
adjunct in forensic identification.
 A literature review by Jeidson Antonio Morais Marques et al
concluded that the comparison of frontal sinus images by
cone-beam computed tomography can be used as an
additional method in the identification process, providing the
expert with greater reliability.

20. 3D facial reconstruction from CBCT data
 3D imaging is becoming more
relevant in all aspects of human life
and substantial effort is spend for the
models regarding the human body.
 CBCT scan data is usually preferred for
3D reconstruction in dentistry.
 Using the data obtained from CBCT

21.  The reconstructed image can be
used for forensic identification.
 This method is still under perfection
trials and research to improve its
efficiency and accuracy.

22. ►One of the major disadvantages with this
technique is noisiness of scanned image
owing to its low radiation dose
►Another major drawback is the
introduction of artefacts due to the
presence of metallic restorations this
results in resolution and detail
deficiencies.
►Motion artefact also creates problems in
the images.

23. REVIEW OF LITERATURE
 A study conducted by IEEE members tried different algorithms
to overcome the drawbacks of CBCT images and to obtain an
efficient and feasible method to develop 3D reconstructed
models.

24. Advantages
 Forensically relevant information could be recorded rapidly
either within a specialist mortuary or in a temporary mobile
mortuary at a disaster scene.
 Practical advantages include relatively small size, portability,
and low cost. Technical advantages include good spatial
resolution and metal artefact reduction.
 The digital data could be sent electronically to odontologists
remote from the scene for examination and archiving.

25.  Conventional radiographic images could be reformatted from
the CBCT data set for comparison with ante-mortem records.
 Reduced body contact would be required with the potential to
eliminate direct examination of the oral cavity.
 The need for surgical resection of the jaws to facilitate dental
examination in cases of body deterioration would be reduced
 CBCT is a non invasive technique in forensic dentistry as
compared with other techniques used in forensic dentistry.

26.  Most CBCT machines allow operator to select the desired
region of interest (FOV).
 CBCT images can be acquired in few seconds .
 Images are seen in multiplanar format. Three-dimensional
reconstruction can be obtained with display from any angle.
 Images are dimensionally accurate.

27. Limitations
 CBCT is more expensive than conventional radiologic
investigations .
 CBCT images suffer from increased noise from radiation scattered
in many directions.
 Introduction of artefacts due to the beam getting scattered by
metallic restorations and implants.

28.  CBCT suffers from motion artefact when a patient moves
during the scanning process .( It can be avoided by using
head stabilizing devices but any movement affects the whole
data set and the whole image rather than just one part).
 Limitations include limited field size and limited soft tissue
contrast .
 Inconsistent quality due various factors.

29. Conclusion
 Forensic odontologists are referred to for clarification by
the judiciary on forensic matters . As crimes are become
increasingly sophisticated , forensic methodology must
keep up to the pace in the technology race. CBCT imaging
can provide the much-needed 3D perspective in certain
cases that require more information that is beyond the
scope of the traditional methods. The use of this
technology is yet limited owing to it’s recent introduction.
There is a need for forensic odontologists to better
understand the role and scope of this imaging modality in
the practice. CBCT in future will prove to be a great tool
and asset to the practice of forensic odontology.

30. REFERENCES-
 White S.C and Pharaoh M. J Oral Radiology 6th Edition.
 N. Jagannathan et al ;AGE ESTIMATION IN AN INDIAN POPULATION USING PULP/TOOTH VOLUME RATIO OF
MANDIBULAR CANINES OBTAINED FROM CONE BEAM COMPUTED TOMOGRAPHY ; (J Forensic
Odontostomatol 2011;29:1:1-6)
 3D Reconstruction from CBCT data- IEEE 978-1-4799-6821-3/14
 Moazzam Jawaid et al ; THE ROLE OF CBCT IN FORENSIC DENTISTRY: A REVIEW ; / International Journal Of
Advances In Case Reports, 2014;1(4):179-183
 Amin W et al ;Osteometric Assessment of the Mastoids for Gender Determination in Jordanians by Discriminant
Function Analysis; American Journal of Medical and Biological Research, 2015, Vol. 3, No. 4, 117-123
 Jeidson Antonio Morais Marques et al ;Cone-beam Computed Tomography Analysis of the Frontal Sinus in
Forensic Investigation; Int. J. Morphol., 32(2):660-665, 2014.
 AS Forrest; Collection and recording of radiological information for forensic purposes ; Australian Dental
Journal 2012; 57:(1 Suppl): 24–32

31. REFERENCES-
 Dilhan İlgüy et al ; Measurements of the Foramen Magnum and Mandible in Relation to Sex Using CBCT ; J
Forensic Sci, May 2014, Vol. 59, No. 3 doi: 10.1111/1556-4029.12376
 Maria Priscilla David et al ; Use of frontal sinus and nasal septum patterns as an aid in personal identification:
A digital radiographic pilot study ; Journal of Forensic Dental Sciences / July-December 2010 / Vol 2 / Issue 2
 Piyush G. Limdiwala and J.S. Shah ; Age estimation by using dental radiographs ; Journal of Forensic Dental
Sciences / July-December 2013 / Vol 5 /Issue 2
 Michael Murphy et al ; Accuracy and Reliability of Cone Beam Computed Tomography of the Jaws for
Comparative Forensic Identification; J Forensic Sci, July 2012, Vol. 57, No. 4 doi: 10.1111/j.1556-
4029.2012.02076.x
 Bianaca S. Krus; 3D CBCT ANALYSIS OF THE FRONTAL SINUS AND ITS RELATIONSHIP TO FORENSIC
IDENTIFICATION
 Tanya Khaitan et al; Cone Beam Computed Tomography: A New Era in Maxillofacial Imaging; Int J Oral Health
Med Res MAY- JUNE 2015 VOL 2

32. THANKYOU