3. Identification of age of individual by tooth remains within
the scope of forensic odontology is a very old concept and
dates back as far as 66 A.D.
At the time of Nero.
An accurate method of age estimation is important for
forensic cases dealing with unknown bodies, parts of
bodies, or skeletons.
Avadhoot Avadhani, JV Tupkari ,Cementum annulations and age determination
Journal of Forensic Dental Sciences, 2009; 1(2).
4. Hard tissues of human dentition are able to resist decay
and degradation long after other
tissues of body are lost.
Hence teeth can be a useful tool in forensic odontology
for age estimation.
Lieberman DE. The biological basis for seasonal increments in dental cementum and their application to archaeological research.
J Archaeol Sci 1994;21:525-39.
6. Cementum is the calcified tissue that surrounds the dentine
and forms the attachment site for the periodontal
fibers that link the tooth to the
alveolar bone.
Backofen UW, Gampe J, Vaupel JW. Tooth cementum annulations for age estimation: results from a large known age validation study.
Am J Phys Anthropol 2004;123:119-29.
7. It is formed as a result of a incremental deposition
throughout life and has shown to triple in thickness
between the ages of 20 and 60 years.
Solheim T:Dental cementum apposition as an indicator of age.
Scand J Dent Res 1990; 98: 510-9.
9. The cementum consists primarily of uncalcified dense
bundles of collagen fibrils which later become mineralized
by deposition of hydroxyapatite crystals.
The varying orientations of crystals may be responsible for
the optical effect of alternating dark and light layers.
Backofen UW, Gampe J, Vaupel JW. Tooth cementum annulations for age estimation: results from a large known age validation study.
Am J Phys Anthropol 2004;123:119-29.
10. This pattern is visible under the microscope as a series of
alternating light and dark lines or bands, which are
known as
Incremental lines of Cementum
Or
Incremental lines of Salter.
Schroeder HE, Orale Strukturbiologie.
Stuttgart- New York: Thieme; 2000.
11. The purpose of this study was to examine the
correlation between the age & number
of incremental lines in
human cementum.
OBJECTIVE
13. This study was carried out in the
Department of Oral Pathology & Microbiology,
IDST College, Modinagar.
The study sample consisted of 15 teeth.
The teeth were collected and stored in 10% buffered
formalin.
The age/gender of the study objects were noted & blinded
during evaluation.
14. Care was taken to ensure the integrity of root cementum
after extraction of the teeth.
Longitudinal ground section of each tooth was
prepared using lathe & arkansas stone .
The sections were then dehydrated, cleared with xylene &
mounted on glass slides.
15. Longitudinal ground section of each tooth was prepared
using lathe & arkansas stone .
The sections were then dehydrated, cleared with xylene,
and mounted on glass slides.
16. 15 extraction patients were identified, their
name/age/gender was documented & extraction samples
were coded #1 to #15.
A longitudinal ground section of each coded sample was
prepared.
18. Longitudinal ground sections of each prepared tooth were
examined under light microscope.
In each section, the area at the junction of apical &
middle third of root & the area where lines were easiest to
count, irrespective of whether the cementum was cellular
or acellular, was selected for counting.
19. Digital images of the incremental lines were recorded for
every section Binocular Adeltavision Microscope in bright
field mode.
Photomicrographs were taken under 4X, 10X & 40X
objective with the help of Olympus digital camera.
20. The images were magnified on the computer and the
cemental lines were counted with the help of Adelta Optec
Apview Imaging Software.
A pair of light and dark lines represents 1 year.
In this study, we counted only the dark lines.
26. The eruption age of the tooth was added to the counted
lines and the estimated age was obtained, as follows:
ESTIMATED AGE =
No. of incremental lines (n) + Eruption age of tooth (t)
28. 20 teeth were initially taken for the study.
During sectioning or grinding, some of the sections broke
completely or parts of cementum broke away; such cases
were rejected (5).
Only intact tooth sections were included in the sample.
33. In studies done by….
• Stott et al (1982)
• Wittwer-Backofen & Buba (2002)
• Charles et al. (1986)
• Kagerer and Gruppe et al. (1992)
• Saxena et al (2009)
• Avadhoot Avadhani (2009)
Observers either had to count directly while looking
through the microscope, or had to use simple photographs.
34. Charles et al.systematically evaluated the distribution of
lines in cementum of the middle third of root in different
sections.
Kagerer and Gruppe applied a method called 'sequential
analysis,' where they tried to find the 'most stable figure' or
the 'most reliable number of layers.'
35. Wittwer-Backofen et al. used 70−80 μm-thick unstained
mineralized sections (storage time was not reported) for
counting the lines.
Kagerer and Grupe counted lines in cementum of 70 μm-
thick unstained mineralized sections using phase-contrast
microscopy.
36. Features crucial to the improvement of results include use
of various microscopic methods like polarizing & phase
contrast microscopy & the digital image enhancement
procedures.
In the current study we utilized brightfield microscopy
and the images taken were converted to grayscale.
The annulations counted were tabulated and the age
estimation was made using established formula.
37. The age estimates from our results varied from the
actual age by -1 to -3 yrs.
According to other studies TCA analysis also was
found to serve as a powerful method for forensic age
estimation.
The accuracy of age estimation based on a 95%
confidence level, was found no more than ±2.5 years.
Backofen UW, Gampe J, Vaupel JW. Tooth cementum annulations for age estimation: results from a large known age validation study.
Am J Phys Anthropol 2004;123:119-29.
39. Teeth are more resistant to decay & degradation as
compared other body tissues.
They can therefore be a useful indicator for age calculations
which may further help in the identification of the human
remains.
40. Counting of cemental annulations has been observed to be
both an easy & accurate method of age estimation in
individuals.
The drawback of this method being the time consuming &
technique sensitive Ground Section preparation.
41. 1. Avadhoot Avadhani, JV Tupkari. Cementum annulations and age determination
Journal of Forensic Dental Sciences, 2009; 1(2).
2. Lieberman DE. The biological basis for seasonal increments in dental cementum and
their application to archaeological research. J Archaeol Sci 1994;21:525-39.
3. Backofen UW, Gampe J, Vaupel JW. Tooth cementum annulations for age estimation:
results from a large known age validation study. Am J Phys Anthropol 2004;123:119-
29.
4. Solheim T. Dental cementum apposition as an indicator of age. Scand J Dent Res
1990; 98: 510-9.
5. Schroeder HE. Orale Strukturbiologie. Stuttgart- New York: Thieme; 2000.
REFRENCES