from 1975 to 1990 thousands of people
died during the Lebanese civil war 50
thousands of those were killed in towns
cities and villages then we have 17
thousands others the missing those who
are still being looked for today their
families wants the remains of their
loved ones returned to them those they
shared good and bad moments with but is
it really possible to identify the
remains of their loved ones among 17
thousands of skeletons this is where
forensic anthropology comes into play
and can attempt to put forward a
comforts inside to a tragic story the
key aspect of forensic anthropology is
the identification of unknown
individuals and of course the very first
step in doing so is to estimate their
sex I want you now think about the key
physical differences between men and
women I know what you’re thinking now
and that is correct but just imagine if
there was no skin or soft tissue
presence what could we do there are
still some methods that can be used for
sex estimation of the skeletons based on
the morphological features of the skull
and pelvis but the only problem here is
that as the organic matter bones do not
survive in poor conditions so we need to
look for a harder element in human body
but what is harder than bone
the enamel that covers our teeth is the
hardest and most highly mineralized
elements in human body and teeth are
often preserved even when the bones are
not you brush your teeth every day you
look at your teeth in the mirror but
have you ever thought that these tiny
white elements in your mouth can provide
us with valuable information about your
age of death your health and diets your
identity your ethnicity your biological
relationships your ancestry and they can
also provide an estimation of your sex
in general males have larger teeth than
females and it could be because of the
longer period of tooth formation in
males the other possibility could be the
sex chromosomes as you know women have
two X chromosomes and men have one X
chromosome and one Y chromosome it has
shown that the effects of the Y
chromosome in two throws is greater than
that of the X chromosome and this may
cause larger – signs in males we can get
a pretty good idea about the differences
between men and women teeth by comparing
their cervical measurements that is the
diameter of the tooth where the crown
which is actually the white part of your
tooth joins the roots that is the part
inside your gums this difference could
be less than one millimeter and can vary
from between 10 to 100 micrometers now
the question is can we really use such a
tiny difference for
estimation in human populations in my
research I’ve investigated this question
while developing a brand new and highly
accurate technique that allows me to
combine 2d 3d and volumetric
measurements of the tooth for sex
estimation in my research I used CT
scans of more than 2,000 teeth from
around 117 male and female individuals
to create a separate 3d model of every
single tooth these models allow me to
take both 2d and 3d measurements of the
crown itself and they also allow me to
take the measurements of those parts of
the teeth which are hidden in the job
such as the volume of the tooths root in
total I recorded more than ten thousands
measurements and by using the
statistical analysis of this data I came
up with a set of equations that
distinguish between males and females my
research showed that male teeth are an
average 0.15 millimeters larger than
female teens and this tiny difference
helped me to sex more than 90% of
individuals correctly this new technique
is faster more accurate and quite
non-invasive in comparison with
traditional techniques such as dental
caliper and it can also be very helpful
for the identification of debod badly
decomposed bodies and disaster victims
because just by having the tooth root we
can still estimate the sex of the
individuals and therefore helping
identify them and maybe giving some
comforts to their families
this is also important considering that
a large number of forensic cases remain
unsolved simply because we cannot
estimate the sex of the individuals this
is always the first step in developing
the biological profile of an identified
bodies and so we doubt it we cannot
proceed further in identifications these
methods also of course have many
forensic studies of sex estimation using
novel and alternative methods like tooth
measurements make a vital contribution
to a field that will always be necessary
and provide crucial help in the
aftermath of mass disasters homos or
homicides and accidents what we all as
the researchers in the field are trying
to do is to bring just a little bit of
comfort to the victim’s family so that
they might be able to cope with such
disasters a little bit more easily at
the ends as barone georges cuvier the
famous french naturalist said show me
your teeth and I will tell you who you
you [Applause]