ODONTOLOGY IN FORENSIC EXAMINATION

P. K.

Central forensic Science Laboratory, Calcutta, India

ADLi TIP iNCELEMELERiNDE ODONTOLOJi UYGULAMALARI Ozct

Di~lerin postmortem ya da antemortem incelcnmesiyle yapllan kimlik tayini ve ya~ tesbitlcrinin adli i~lemlerde biiyiik onemi olmasma kaqm, bu konudaki uygulamalarda radyolojik yontemlcre yeterince yer verilmemi~tiL Di§ \,iiriikleri slkltgliun fazla oldugu toplumlarda Gus/aJson (1950) ve Dali/z

(l962)'in yiintemleri yetersiz kalmaktadlL Bu nedenle, \,iiriik ve normal di~leri olan ki~ilerdcn alman intraoral rontgen resimleri ile stercomikroskopik incelemclcr uygulanarak ki~inin ya~l, cinsiyeti, bireysc! nitelikleri ve ilgili ki§inin di§ konumlanmn ozclliklerinin saptanmasma \,ah~tldl. Elde edilen sonu\,lar, bu ama\,la uygulanmasl onerilmi§ diger yontemlerle kaqt!a~tmldl.

Summary

Individualization and age determination through morphological study of teeth postmortem or antemortem has substantiated its importance in our society and jurisprudence for some decades, but its radiographic study, as conceived, has not been done exhaustively to extract its importance in medicolegal science. Carious teeth whose percentage in population is quite high docs not follow

Gus/aJson (1950) and Dalitz (1962) age determination regression line based on wear and tear of nonnal teeth. Study through intraoral X-ray photography of normal and carious teeth and stereomicroscopic examination of some ground sections of teeth were carried out in an endeavour to find out age, sex, individual characters, dental setup of the person concerned.

Key words: Individualization - Carious and normal teeth -X-ray photography - Stereomicroscopic examination

INTRODUCTION

Teeth are sent for forensic examination either detached from the skull or socketed in

the jaw of the skull. Their morphological examination

based

on

some

parameters

accompanied by thinning

the

teeth by grinding and rubbing provides us with an idea of

approximate age of the person concerned.

Gustafson

(1)

measuring

six

parameters of

wear

and

tear of permanent canine teeth namely attrition, periodontosis, secondary,

dentin, cementum apposition, root transparency, and root resorption could determine age

with an

error of

±3.63 years in 33% and ±7.3%

years in 4-5% of teeth examined.

28 P.K. BANERJEE

Dalitz

(2) cons

idering four parameters

namely

attrition,

periodontos

i

s, secondary

denti

n and

roo

t t

ransparency brought

down

the error

-

to

±6

years

in 35%

cases

.

Gu

sta

f

son

(1)

divided each

para

meter into four

subpa

ram

e

t

crs

l

ike

A-O

to

A-3

(A

-att

rition), P-O

to

P-3 (P-

periodontosis),

S-O

to S-3 (5-

secondary

dentin), C-O to

C-3

(C- cemen

tum

apposi

ti

on), R-O to

R-3

(R

-

root

resorption) a

nd

T-O

to

T-3

(T-

root

tr

ansp

ar

ency)

based on

the depth

of these

paramete

r

s

and plotted these

points

on

the

graph

(total

po

ints,

Tp=

An

+

Pn

+

Sn

+

en

+

Rn

+

T

n).

Regression

line prepared

with

the

known

age

of

th

e

teeth is

then compa

r

ed with

the

line

prepared

w

i

th the

points

of

exp

e

rimental

teeth

.

R

ecen

t

trials

on

the

determination of age

f

ro

m

teeth

like counting

cementum

thickness (3-5) or

r

oot transparency

of Miles (6)

are not

complete

one

.

G

ustafson's

method

is

predominantly

followed,

but

a numbe

r

of

factors exerting

t

heir effect, its

application

and

limitation arc greatly reduced.

!\.

significant

chunk

of

po

pulation

is affected

with dental caries

(7). Carious teeth do

not

rollow

age

de

t

ermination

reg

r

ession line

whic

h

was prepar

e

d on the

study of

normal

:ccth

on

ly. For

a

deta

iled

stu

d

y of

these carious teeth,

f

or better

un

d

erstanding

of inne

r

structure of any

tooth

p

articularly in vivo

and for

nondestructive

examina

tion

roen

tgenographic study was though

t

as

better

productive

and confirma

tive.

[n the

present endeavour

a r

adiographic

study of

these

carious teeth along with teeth

in

v

ivo

has been

carriee! out

to evaluate

the regression line of

G

ustafson.

Along with

this habi

t

and habitat of

these

p

ersons

possessing

these in

fl

ue

n

cing the

na

ture,

age,

shape o

f mo

uth

has

also

been recorded. Some critical observations

have also been

noted

which do not

follow

norma

l

course

of aging.

diverse profession, eating hahit and age arc recorded. A few incisor canine, premolar and mostly molar

(latter having maximum wear and tear) from both the jaws arc considered for detailed examination. Regression line for age detemlination following Guslajwn method is plotted on the graph. Sixteen teeth

socketed in the jaws of the skuli arc taken and after preparing thin sections (0.2 mm) by grinding and

mbbing on ground glass with carbomndum powder (different grades -eourse to finc) morphology of these

teeth were studied (fig. 1). Altempts were also made to detennine age from the skull as well as from the teeth sent for forensic examination.

Table I shows the difference of parameters due to aging from the roentgenographic study.

Table

r.

!\' UIIl ber Chll.acters A l' S C R T Age in yeal'

of teeth (arprox.)

---~.~ _. _ _ _ _ ____ • _ ____ 0. ____ '-._ -__ •

.--_ ... _ .. - - - - --"

2 Nonnal, inciser, male, healthy, vegetarian 2 1 0 28

"3 Acute carious, inciser, female, vegetarian 3 2 0 2 2 27 2 l\onnal, canine, m~lc, healthy, nOll vegetarian 0 0 0 0 0 0 j 8

1 Acute carious, canine, male, Tlonvcgctarian 2 2 0 0 1 19

Nonnal, canine, fctnalc, healthy, nonvegetarian 2 2 0 39

3 Chronic carious, canine, female, nonvegctarian 3 2 2 2 1 42 3 Normal, canine, male, healthy, vegetarian 1 0 0 0 22

Chronic carious, canine, male, healthy, nonveg. 2 2 I 24

3 Nonnal, premolar, female, healthy, vegetarian 3 3 2 2 2 2 38 1 Acute carious, premolar, female, vegetarian 3 3 3 3 3 2 42 3 Nonnal, molar, male, healthy, vegetarian 3 3 3 2 2 2 47

2 Acute carious, molar, male, vegetarian 3 3 3 3 I 2 50

2 Normal, molar, female, healthy, nonvegetarian 2 2 0 3 1 1 32

Chronic carious, molar, female. nonvcgetarian 3 3 3 0 2 23

Figure 2. Lateral chrunic caries of 2nd and 3rd

molars of 27 years' male.

Figure 3. Roentgenograph of unhealty teeth, but

30

Figure 4. Acute pit and fissure caries on occlusal surface touching pupl of 31 years' female.

DISCUSSION and RESULT

P.K. BANERJEE

Figure 5. Lateral and proximal acute caries, eat

-en away almost half of enamel and dentin of 37 years' female.

Presen

t

endeavour is

not

sufficient enough to draw a conclusion with regard to

inadequacy of material and

requisite

i

nformation

f

rom

the donor.

With limited

resources,

expcTimental material and

information following

points bear

in

mind.

1.

Wear

and tear is always advanced in carious teeth (Fig

.

2) than norma

l

teeth (Fig.

3) particularly attrition of enamel and periodontosis.

Root

transparency is

not

so

affected

i

f

lesion is

not so deep. Sometimes carious erosion and sepsis arc

so deep

with

cystic

growth that estimation of

any

of the

parameters

is not

possible

(Figs. 4,5). Carious

teet

h

do

not

f

ollow Gustafson regrcssion line,

and decrease of parameter

arc

always

anomalous

(Table I), as such linkage between age and wear and tear could not be

drawn.

2.

It

has been

noticed

that attrition was more advanced in

smooth

surface caries and

erosion in

pit

and fissure caries sometimes reaches upto root. Acute caries

which arc

predominent

in child and young increase the rate of attrition and spoil secondary dentin.

3.

It

is

fclt that thinning

teeth by

grinding and rubbing on ground glass with

carborundum powder is a cumbersome process and roots of the

teeth

particularly those

of molar are broken, whereas

intraoral

filming of

teeth,

though a bit

costly

is

quick,

safe

and

fruitful. Teeth is not to

be sacrificed

when studrcd thro

u

gh radiographic film.

4.

Roughly

it

can be

inferred

if regression curve plotting

gives

±5 flexibility of age

on the morpholog

i

cal study (sectioning and threc dimentiona

l

view) of

normal

teeth,

roentgenographic

study

when added to

it before

sectioning on the same teeth

will

reduce

its flexibility to ±3

.

(Viz. age of a person having no birth

ce

rtifi

cate),

there is

n

o other means but

t

o take

intraoral radiographic photo and study these.

Figure 6. A roentgenograph of decayed and filled

teeth of 29 years' male.

Some General

Observations:

Figure 7. Lateral and proximal acute caries,

cat-en away almost half of enamel and dentin of 37 years' female.

1. This

atrophy and subsequent aging of teeth

is different in diffcrent variaties of

normal teeth,

Viz.

dec

i

duous and permanent

teeth, maxillary

and mandibular t.eeth,

incisor, canine, premolar, molar teeth of the

same person, even different

molars of the

same jaw

(Fig. 7). So

it is a

herculean

task to prepare a control

regression line with

different varieties of

teeth to

be compared with the questioned one.

2. Etilogy of carious teeth as well as normal teeth and omnipresent hereditary factor

of human

physiology reduce the importance of Gustafson method. It has

been

noticed

that rate of attrition

differ in teeth of different persons of same age, sex, eating hab

i

t and

habitat. It

has

also been

noticed that

the attrition

is different in

the

teeth of identical

twins in old age born

and brought up almost in

the

same environmental conditions. It

seem

s

thickness and hardness of enamel and periodontosis are to a great extent hereditory

character which do

atrophy

with

age but

not following a regular p

attern.

Rather othe

r

four factors namely secondary dentin formation, degree of cementum

apposition, degree

of root re

so

rption and degree of root transparency follow

a regular pattern of

aging

.

Four

parameters

may not encompass all the points of teeth aging from

diversified source (2).

3.

From

the roentgenographic study of teeth

it has

been

noticed that teeth of pure

vegetarian

are much prone to attrition

and periodontosis rather than

those of

nonvegeta-32 P.K. BANERJEE

rian

.

And most probably rate

of

teeth attrItIOn

is

mo

r

e in female

tha

n

in male.

Obviously wear and tear of

tee

t

h and subsequent a

ging is

mo

r

e advanced

in

dirty and

unhealthy teeth than clean

t

eeth

though

the

possessors may be of the

same age

. Dental

paste

a

nd powder and the

water

will cortainly influence

a

gi

n

g

of

t

he

te

eth.

U

se

of

stannous

fluoride

i

n paste or as medicine

dec

r

ease the ra

t

e of wear

an

d tear of

t

eeth and

a

l

so

arrest carious

le

sio

ns.

4

.

So while adding flexib

i

lit

y

(±) to

the age, D1tlF, veget

a

rian,

f

emale, unhealthy

teeth

will be on

+

side

and

normal,

nonvege

tarian,

male, clean will

be

on

-

side of

calculation.

Acknowledgement

The author thanks Dr. S. Paul, Dentist, Calcutta for providing with material and information and Mr.

V. K. Bajpai, Photographer, SFPS for assistance.

REFERENCES

Gustafson, G. (1950) 1. Am. Denl. Assoc., 41, 45-54.

2 Dalitz (1962) 1. Forensic Sci. Soc., 3, 11-13.

3 Lipsinic, F.E., Paunovich, E., Houston, G.D., Robinson, S.F. (1986) Inl. f. Forensic Sci., 31,

982-989.

4 Stoll, G.G., Levy, 13..\1. (1982) f. Dent. Res., 61,814-817.

5 Miller, C.S., Dove, S.B., Cottone, I.A. (1988) 1. Forensic Sci., 33, 137-143.

6 1\1l1es, A.E.W. (1963) 3rd Inlerrwlional Congress Series, No. 80, Excerpta Medica foundation, Amsterdam.

7 Shafer, W.G., Hine, M.K., Levy, B.M. (1983) in A Texl Book of Oral Palhology, pp.406-409,

Saunders International , Philadelphia.

Reprints request to:

Dr. Pranab Kumar Banerjee

Central Forensic Science Laboratory Government of India

30 Gorachand Road

Calcutta - 700 014