7/30/2019 demograph 2.pdf
1/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 10
Status of Third Molars In North Indian Population - A
Radiographic Survey
Bhawandeep Kaur1, Soheyl Sheikh2
_______________________________________________________________
Abstract
Background: With the change in number of life style factors, lack of proper dental care and
genetic factors, the incidence of agenesis and impactions of third molars is increasing.
Material & Method: Panoramic radiographs of 960 males and 880 females of age group
ranging from 18-25 years were selected irrespective of sex, caste, nutritional and socio-
economic status.
Results: Impaction rate was found to be 42.98% having no sexual predilection. Vertical
impaction was of 36.6%, more than mesio-angular 29.2%. Agenesis rate was found to be
15.7%. Bilateral agenesis of third molars in maxilla was more 12.6% as compared to
mandible 0.86%.
Conclusion: Evolutionary changes and genetic factors are predisposing humans for having
agenesis and impaction of the third molars.
Key-words: Agenesis, Impaction, Third Molar.
___________________________________________________________________________
Introduction
Evolution is a complex subject and
many different theories regarding this
concept are emerging. The old ones are
being reexamined in the light of emerging
genetic discoveries.
One common and widely accepted
explanation contends that molars evolved
when human ancestors roamed the Earth
on four legs, more than hundred million
years ago. Due to biological, cultural and
evolutionary changes with time, humans
have experienced a decreased dependency
on all tooth types. This is especially the
case where third molars are concerned.
Anthropologists state that constantly
increasing cerebration of man is enlarging
his brain size at the expense of his jaws1,2.
It is a well known fact that nature
tries to eliminate what is not in use.
Likewise, the advent of civilization and
use of soft and refined diet has eliminated
the human need for large and powerful
7/30/2019 demograph 2.pdf
2/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 11
jaws. In this decrease in size, the number
of certain teeth no longer necessary for
function of mastication and feeding, areeither getting increasingly impacted or are
not developing at all. So, the incidence of
the third molars getting impacted or
genetically missing is the highest. Hence,
third molars may be considered as
Vestigial2
Agenesis is the congenitally
absence of at least one permanent tooth. It
is the most frequently encountered dental
anomaly. Since the first reported study by
Albert W. Goblirsch in 19303, there have
been several studies done in various
countries all over the world proving that
the percentage of agenesis of third molar
agenesis is increasing.
An impacted tooth is one which,
because of some impediment, is prevented
from assuming its normal position in the
arch at its physiological time of eruption.
The time of eruption of the third molars is
also variable, starting at the age of 16
years. Averages of eruption times of 17.8,
19.0, 20.5 & 24 years have been reported4.
The third molar is the last tooth to
erupt. Hence it may readily become either
impacted or displaced if there is
insufficient room for it with in the dental
arch4.
It is generally accepted that
patterns of facial growth, jaws and tooth
size are inherited and likely to differ
among populations and races. Previous
studies have shown the incidence of
impaction of third molars as 47.44%
(1970), 68.6% (2003), respectively5,6.
Studies have been conducted to
determine the agenesis of the third molars
in different parts of the world like Jordan,
Australia, Jerusalem, Singapore, South
Korea etc. but no similar study has been
documented till now in North India7-11.
The present study was undertaken
to review the prevalence of agenesis as
well as impaction of third molars in
population of age group 18-25 years.
Aim & Objectives:
The aim and objectives of the study were
as follows:
1. To assess the prevalence of agenesis
of the third molars in age group ranging
between 18-25 years.
2. To assess the prevalence of impacted
third molars in age group ranging between
18-25 years.
7/30/2019 demograph 2.pdf
3/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 12
Materials & Methodology:
In this study, a total number of
1840 students which were totally
asymptomatic, of age group ranging from
18-25 years irrespective of sex, status,
caste were selected randomly from
different institutions of M. M. University,
Mullana, Ambala, Haryana. An ethical
clearance was obtained from the ethical
committee of M.M.University,Mullana,
Ambala, Haryana.
The subjects were selected
irrespective of their sex, caste, nutritional
and socio-economic status. Their
demographic data and previous history of
extraction of third molar was recorded in
the designed proforma. The purpose of the
study was explained to them verbally and
written consent was obtained.
Exclusion Criteria:
1. Subjects having history of third
molar extraction were not included
in the study.
2. Subjects having any history of
pain in third molar region, trismus
was not included.
Radiographic procedure was
accomplished by Panoramic machine
(Rotagraph plus, panoramic and
cephalometric machine VILLA SISTEMI
MEDICALLI, 2002, Made in Italy) at 80KVp, 10 mA for 17 seconds with total
filtration of 2.5mm aluminium. 5X12
inches curved rigid aluminium cassette
with green light sensitive intensifying
screens (Konika KR-II) and 5X12 inches
Kodak T-Mat green sensitive panoramic
dental films made in U.S.A. by Eastman
Kodak, Rochester, New York were used in
the study. The radiographs were observed
by two observers and were examined for
the following:
a) Number of third molars present perperson
b) Number of impacted of thirdmolars
c) Number of third molars revealingagenesis
Impacted third molars were also
grouped according to their position as
vertical, horizontal, mesioangular,
distoangular impacted molars
Results
Total number of students examined
was 1840 including 960 males and 880
7/30/2019 demograph 2.pdf
4/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 13
females having age group ranging from
18-25 years.
Agenesis of all third molars was
found to be in 104 students (5.65%) as
shown in figure 1. Agenesis of the third
molars was found to be more in males as
compared to females. In maxilla bilateral
agenesis of third molars was found in 232
cases (12.6%) as shown in figure 2. In
mandible bilateral agenesis was found to
be in 16 cases (0.86%). The prevalence of
agenesis of third molars is shown in table
1. Impaction rate was found to be 42.98%
in total subjects as shown in figure 3.
Fi g 1Showing agenesis of all the third molars
Fi g 2:Showing bilateral agenesis of third molars
in maxilla.
F ig 3:Showing impacted all third molars as well
as 37.
The various types of impaction
status of third molars is being summarized
in table 2.
Impaction status of third molars in
male and female was found to be in the
ratio of 1:1.
Impaction status in maxillary and
mandibular dentition was found to be in
the ratio of 1:1.74.
Discussion
The third molars are the last teeth
to erupt in the oral cavity. Since they erupt
at about the time when the youth goes off
in to the world to become wise, they
referred to as wisdom teeth.
The word wisdom tooth is derived
from latin word dens sapientiae. In many
Spanish speaking countries it is called as
the molar of judgement. This is because
when they appear, the person is considered
to have better judgement ability than that
7/30/2019 demograph 2.pdf
5/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 14
of a child. Turkish refers the third molar
directly to the age at which wisdom teeth
appear and calls it 20 yas disi which means20th year tooth.
Racial variation, nature of diet,
degree of use of masticatory apparatus and
genetic inheritance can affect the jaw size
and tooth size12, 13.
The third molars are the teeth that
are most common congenitally missing. If
present, the third molars may follow an
abnormal eruption path and become
impacted as a result of the skeletal
insufficiency in the areas where they
normally erupt. Impacted third molars are
developmental pathologic medical
deformities characteristics of a modern
civilization.
To our knowledge, this is the first
study in Haryana, a state in Northern part
of India, to evaluate the status of third
molars in population of age group ranging
from 18-25 years. As such, this study hasthe potential to make a substantial
contribution to ongoing debate on the
outcome of third molars i.e. whether they
should be prophylactically removed or
preserved.
The prevalence of third molar
impaction after examining 1840 subjects
of both sexes was found to be 42.98%.
Previous studies have shown prevalence of
impaction of the third molars as of 20.5%(1959, Nanda & Chawla), 37%
(1993,Vohra FS), 33% (1995, faiez N.
Hatteb),40% ( 1998, Dr. Vandana KV),
68.6% (SL Quick, 2003) respectively5-
7,14,15.
Unlike Hellman, Hugson &
Kugelberg, we observed no sexual
predilection in incidence of third molars
impactions16, 17.
In our results, 7360 third molars-
1160 third molars showed agenesis & out
of remaining 6200 third molars, 4600 were
found to be impacted. Most of the teeth
were in vertical impaction state (36.6%) in
contrary to the findings of previous
studies, which concluded that
mesioangular impaction was the common
state of impacted third molars.(8)
However, prevalence of mesioangular
impaction was 29.2%, distoangular 16%
and horizontal 18% respectively.
In our study, agenesis of the third
molars is found to be 15.7% as compared
to previous studies done by Sandhu 1982
(7.78%), Faeiz N. Hattab 1995 (9.1%),
Daniela Gamba Garib 1995 (20.7%). Our
study has documented prevalence of
7/30/2019 demograph 2.pdf
6/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 15
agenesis in the maxilla in 12.6% of
examined subjects which is more as
compared to the subjects exhibitingagenesis of third molars bilaterally in
mandible (0.86%)5, 7, 18.
In our study, total number of 80
subjects right maxillary third molars, 88
subjects left maxillary third molars, 48
subjects left mandibular third molars, 32
subjects right mandibular third molars, 232
subjects bilateral maxillary third molars,
16 subjects bilateral mandibular third
molars & 104 subjects all third molars
showed agenesis on the panoramic
radiographs.
Previous studies have shown
incidence of agenesis is more in males
(Sandhu S.S, 1982) and females (Vohra
F.S, 1993), but our study has revealed no
sexual predilection5, 14.
Previous studies have shown the
incidence of agenesis of the maxillary
third molar on the right side (Vohra F.S)while contrary to these finding our study
has shown no predilection to any side of
maxilla14.
Panoramic radiographic procedure
was selected over the IOPA, due to its
advantage of being a fast process and
wherein the view of entire maxilla-
mandibular region on a single film could
be obtained. The procedure is convenientto patient and requires little expertise of
the radiologist.
The main advantages of this
procedure is that the status of developing
third molars can be viewed, their relation
to inferior alveolar dental canal, type of
impaction and site of third molar can be
easily revealed.
The main advantages of this
procedure is that the status of developing
third molars can be viewed, their relation
to inferior alveolar dental canal, type of
impaction and site of third molar can be
easily revealed.
The growth of maxilla and
mandible ceases by 16-17 years of age.
The mean age of subjects included in this
study was 20.94 years which is very close
to average age of eruption of third molarsreported to be of 20.3 years. Schersten et
al19 suggested that 20-25 years is the most
suitable age for studying the third molars.
DA Vies PL20 showed agenesis of
third molars to be more in females as
compared to males. But contrary to his
findings studies conducted by Hattab FN,
7/30/2019 demograph 2.pdf
7/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 16
Lynham A, Mok YY,Thompson GW et al
showed no sexual predilection for agenesis
of the third molars. But in our study results
revealed the agenesis of the third molars
more in males7, 8, 10, 21.
Table 1: Prevalence of Agenesis of the Third molars
TOOTH NUMBER INCIDENCE
18 4.34% (80subjects)
28 4.78% (88 subjects)
38 2.60% (48 subjects)
48 1.73% (32 subjects)
18,28 12.6% (232 subjects)
38,48
18,28,38,48
0.86% (16 subjects)
5.65% (104 subjects)
Table 2:Prevalence of Impacted Third molars
Mesioangular 29.2%
Distoangular 16%
Vertical 36.6%
Horizontal 18%
Conclusion & Summary
Among 1840 subjects of age group
ranging from 18-25 years who were
screened for impacted third molars,
42.98% showed one or more third molars
impacted without any sexual predilection.
Agenesis of third molars was found to be
15.7%. Depending upon the impaction
status, treatment options can be planned
for impacted third molars. But probably
because of changing food habits, there
7/30/2019 demograph 2.pdf
8/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 17
may be complete agenesis of third molars
in future, if the same trend continues.
Further in the evolutionary ladder of livingkingdom the presence of third molars in
developed body system of human being
seems irrelevant and loathsome instead of
being helpful and work-worthy as happens
to other living being lower down.
References
1. Anthony R, Silvestry JR, Singh I.The unresolved problem of the
third molar. J Am Dent Assoc
2003;134(4):450-455.
2. Bergman J. Are wisdom teeth(third molars) vestiges to human
evolution. TJ arch 1998;12(3):297-
304.
3. Goblirsch AW. A study of thirdmolar teeth. J Am Dent Assoc
1930;17: 1849-1854.
4. Yamaoka M, Furusawa K,Fujimoto K, Uematsu T.Completely impacted teeth in
dentate and edentulous jaws. Aust
Dent J 1995; 41(3): 169-172.
5. Sandhu SS, Kapila BK. Incidenceof Impacted Third Molars. J Ind
Dent Assoc 1982; 54:441-444.
6. Quek SL, Tay CK, Toh SL, LimKC. Pattern of third molar
impaction in a Singapore Chinesepopulation : A retrospective
radiographic survey. Int J Oral &
Maxillofac. Surg. 2003; 32:548-
552.
7. Hattab FN, Rawashdeh MA,Fahmy MS. Impaction status of
third molars in Jordanian students.
Oral Surg Oral Med Oral Pathol
Oral Radiol Endod 1995;79:24-29.
8. Lynham A. Panoramicradiographic survey of hypodontia
in Australian Defence force
recruits. Aus Dent J 1990;35(1):19-
22.
9. Shapira J, Chaushu S, Becker A.Prevalence of tooth transposition,
third molar agenesis and maxillary
canine impaction in individuals
with Down syndrome. Angle Ortho
2000; 70(4):290-296.
10.Mok YY, Ho KK. Congenitallyabsent third molars in 12-16 years
old Singaporean-Chinese patients:
a retrospective radiographic study.
Ann Acad Med Singapore 1996;
25(6):828-830.
7/30/2019 demograph 2.pdf
9/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 18
11.Chung CJ, Han JH, Kim KH. Thepattern and prevalence of
hypodontia in Koreans. Oral Dis2008; 14(7):620-625.
12.Aitasalo K, Lehtinen R, Oksala E.An orthopantomographic study of
prevalence of impacted teeth. Int J
Oral Surg 1972; 1:117.
13.Haralabakis H. Observation on thetime of eruption, congenital
absence and impaction of the third
molar teeth. Tans Eur Orthod Soc
1957; 33:308-312.
14.Vohra FS, Gill AS., Sharma SP. Aradiographic study of agenesis of
third molars in individuals with
clinically absent third molars. J of
Ind Dent Assoc 1993; 64(7):221-
224.
15.Vandana KV, Dayakar MM.Impacted third molars: Prevalence
in rural Indian university students.
J of Ind Dent Assoc 1998; 69:94-
96.
16.Hellman M. Our third molar teeth:their eruption, presence and
absence. Dent Cosmos 1936;
78:750-762.
17.Hugson A, Kugelberg CF. Theprevalence of third molars in a
Swedish population. Anepidemiological study. Commun
Dent Health 1988; 5:121-138.
18.Daniela GG, Zanella NLM, Peck S.Associated dental anomalies: case
report. J. Appl. Oral Sci. 2005;
13(4).
19.Schersten E, Lysell L, Rohlin M.Prevalence of impacted third
molars in dental students. Swed
Dent J 1989;13:7-11.
20.Davies PL. Sexual dimorphism inagenesis of teeth. J Dent Res
1968;47:1198.
21.Thompson GW, Popovich F,Anderson DL. Third molar
agenesis in the Burlington Growth
Centre in Toronto. Commun Dent
Oral Epidemiol 1974;2(4):187-192
http://www3.interscience.wiley.com/journal/121439675/abstract?CRETRY=1&SRETRY=0#c1http://www3.interscience.wiley.com/journal/121439675/abstract?CRETRY=1&SRETRY=0#c17/30/2019 demograph 2.pdf
10/10
ORIGNAL RESEARCH
Journal of Dental Peers, Vol.1, Issue 1, April 2013 19
Correspondence:1Dr Bhawandeep kaur, Senior Lecturer, Department of Oral Medicine &
radiology, Genesis Institute of Dental Sciences & Research, Ferozepur, Punjab, India
Contact Info:
E mail:[email protected] No: +91 81463756022DrSoheyl Sheikh
2, Professor & HOD, Department of Oral Medicine & Radiology, M.M.
College of Dental Sciences & Research, Mullana, Ambala
mailto:[email protected]:[email protected]:[email protected]:[email protected]