Download frequency of missing maxillary permanent lateral incisors — a study

Original Article
FREQUENCY OF MISSING MAXILLARY PERMANENT
LATERAL INCISORS — A STUDY
FARWA BATOOL
2
ALIA AHMED
3
SHARAZ AHMED
4
SAMAR E ZAHRA
1
ABSTRACT
There are a number of dental anomalies and congenital absence of the teeth is relatively more common. These can cause the patient to seek treatment because of esthetic concern. The aim of this study
was to determine the frequency of agenesis of maxillary permanent lateral incisors.
A total of 364 outdoor patients, both male and female, were included in the study from age 12 to
40 years. The data was collected and entered in a proforma and was analyzed by using SPSS 17.0.
The results showed that only 1.6% of patients had congenitally missing permanent maxillary lateral
incisors, with equal distribution within each gender i.e. male 1.7% and in female 1.6%. It was found
that all cases have missing permanent maxillary lateral incisors unilaterally with no bilateral distribution. It was concluded that prevalence of congenitally missing maxillary lateral incisor is very
low in our population.
Key Words: Agenesis, hypodontia, maxillary lateral incisor.
INTRODUCTION
Smile esthetics is considered critical because of
its enormous psychological impact on a person. A
pleasant smile boosts an individual's confidence and
a good dentition, with a proper soft and hard tissue
balance can achieve this goal. Teeth which are visible
during smile form the esthetic zone and are vital for
achieving esthetic balance. While considering hard
tissue dentition any rotated, crowded or missing teeth
can lead to unaesthetic smile. A number of causes
can lead to missing teeth, for example, either they
are impacted or they fail to develop altogether (tooth
agenesis).
The term ‘hypodontia’ is used for congenital absence
of one or more teeth, either in primary or permanent
dentition, excluding the third molars.1 It is more prevalent in permanent dentition than the primary dentition2
and females are more frequently affected than males.1,3
Hypodontia can be associated with a syndrome or can
occur independently.
Dr Farwa Batool, BDS, IIDC, Riphah International University
Email: [email protected] Cell: 0336-610-2174 Correspondence Address: House No. 152, Street 1, Sector 1, Airport
Employees Housing Society, Rawalpindi
2
Dr Alia Ahmed, BDS, FCPS, Professor Operative Dentistry IIDC,
Riphah International University. Address: House No. 124-A,
Street 46, I-8/2, Islamabad
3
Dr Sheraz Ahmed, BDS, IIDC, Riphah International University.
Received for Publication:
April 28, 2016
Revised:
June 7, 2016
Accepted:
June 7, 2016
1
Agenesis of lateral incisors can occur unilaterally
or bilaterally, negatively affecting the smile esthetics.
Various syndromic conditions (Ectodermal dysplasia,
van der Woude syndrome, Down’s syndrome, Rieger
syndrome and Book syndrome) can lead to missing lateral incisors,1,3,4 but mostly the problem is encountered
in healthy individuals (non-syndromic hypodontia.3,4
Etiological factors for non-syndromic hypodontia are
changes in the dental lamina formation, failure of tooth
germ to develop at the optimal time, space limitations
and genetic factors.4,5,6
Owais et al evaluated the prevalence of missing
maxillary lateral incisors in a sample of 500 orthopantomogram (OPG) and they found that 4.16% maxillary
lateral incisors missing.7 Similarly another study revealed that the ratio of bilateral to unilateral absence
of maxillary lateral incisor teeth was 2:3.8
The present study was aimed to establish the
frequency of missing maxillary lateral incisors at hospital setting in order to acquire prevalence in general
population of the city and to reach early diagnosis and
carry out management at an early age.
METHODOLOGY
The prospective cross sectional study was carried
out at outdoor patients department of Islamic International Dental Hospital, Islamabad, from June 2015 to
Pakistan Oral & Dental Journal Vol 36, No. 2 (April-June 2016)
301
Frequency of missing maxillary lateral incisors
November 2015. Non-probability purposive technique
was applied. Before the start, study was approved by
ethical review committee of the institute. Subjects were
selected according to inclusion and exclusion criteria
(Table 1).
A Proforma was designed for data collection. 364
subjects, both male and female, of age from 12 to 40
years were examined and results were filled on this
proforma. The lower age limit of 12 years was taken
so, as to allow lateral incisors to fully erupt into oral
cavity. Informed consent was taken from the patients.
The examination was carried out by using routine
diagnostic instrument i.e. dental mirror, which was
used to retract upper lip of the patient by the researcher. A periapical radiograph was taken if permanent
maxillary lateral incisor was found missing on clinical
examination. Panoramic radiograph had been advised
to patient if required.
SPSS (statistical package for social sciences) 17.0
was used to enter and analyze the data. Frequencies
and percentages were described for qualitative variables
(gender, missing maxillary lateral incisors). Effect
modifiers such as gender, tooth position were controlled
by stratification. An arbitrary value of p<0.05 was
considered significant.
RESULTS
In the present study 180 male and 184 female were
examined from a total of 364 people. This study found
that 1.6% of subjects had missing maxillary lateral
incisors. Out of 180 males 3 (1.7%) had missing maxillary lateral incisors and out of 184 females 3 (1.6%)
had missing maxillary lateral incisors. All 6 missing
maxillary lateral incisors were unilateral. No bilaterally
missing maxillary lateral incisors were found among 364
subjects. The prevalence of missing maxillary lateral
incisor is summarized in Table 2.
TABLE 1: INCLUSION AND EXCLUSION CRITERIA
Exclusion criteria
Inclusion criteria
Patients who, has been diagnosed with any syndrome due to which they have • Patient aged 10-40 years.
shown feature of hypodontia.
First trimester pregnant female, to avoid over dosage of radiation.
Both male and female have
been included.
Patients who has previous history of extraction and radiographic (periapical/
panoramic) evidence of mineralization.
Traumatic avulsion
Impacted incisors
Uncooperative patient
Medically compromised patient
TABLE 2:PREVALENCE OF UNILATERAL VS BILATERAL MISSING LATERAL
INCISORS WITHIN GENDER
Gender
Missing lateral Unilateral
incisors
missing
Count
Female
Male
3
3
6
% within gender
50.0%
50.0%
100.0%
% of Total
1.6%
1.7%
1.6%
% within missing lateral incisors
Bilateral present Count
.8%
.8%
1.6%
181
177
358
% within gender
50.6%
49.4%
100.0%
% of Total
98.4%
98.3%
98.4%
Count
49.7%
48.6%
98.4%
184
180
364
% within gender
50.5%
49.5%
100.0%
% of Total
100.0%
100.0%
100.0%
50.5%
49.5%
100.0%
% within missing lateral incisors
Total
Total
% within missing lateral incisors
Pakistan Oral & Dental Journal Vol 36, No. 2 (April-June 2016)
302
Frequency of missing maxillary lateral incisors
TABLE 3: CHI SQUARE TEST COMPARISON OF PREVALENCE OF MISSING LATERAL
INCISORS BY GENDER
Value
Df
Asymp. Sig.
(2-sided)
Pearson Chi-Square
.001a
1
.978
Continuity Correctionb
.000
1
1.000
Likelihood Ratio
.001
1
.978
Fisher's Exact Test
Linear-by-Linear Association
.001
N of Valid Cases
364
1
Exact Sig.
(2-sided)
Exact Sig.
(1-sided)
1.000
.647
.978
a. 2 cells (50.0%) have expected count less than 5. The minimum expected count is 2.97.
b. Computed only for a 2x2 table
When applying chi-square to determine any significant gender difference it was seen that male and
female had equal chance of having unilateral missing
maxillary lateral incisors (Table 2). And the difference
is not statistically significant at a p value of 0.05. Since
the p value has been calculated as 0.978, it shows that
the association between gender and missing maxillary
lateral incisors is very weak (Table 3).
DISCUSSION
In the maxillary anterior region (esthetic zone),
maxillary lateral incisor is the most common congenitally missing permanent tooth, representing
approximately 20% of all dental anomalies. 9,10 Muller
observed that in a North American population, the
maxillary lateral incisor was the most frequently
missing tooth in individuals with agenesis of only
one or two teeth.
The frequency of missing lateral incisors reported
by Amin F11 et al was 2.17%. Their study was conducted
on 230 orthodontic patients between the chronological
ages of 10 and 32 years (mean age 16.6 years), with 84
males and 146 females. They have reported the unilateral tendency of missing maxillary lateral incisor,
and females had more tendencies towards hypodontia
than males. In studies of Al- Emran and Al-Humayani
F12 maxillary lateral incisors agenesis was reported as
comparatively low as 0.6% and 0.7%. In another cross
sectional study conducted in India prevalence of missing
lateral incisors was 0.3%.2
There has been reports on country to country and
racial variation in hypodontia.8 The reported prevalence
of missing teeth, excluding the third molars in both
sexes combined, varies from as high as 10.1% in the
Norwegian population13 and as low as 0.3% in the Israeli
population. The prevalence of hypodontia investigated
in Australian orthodontic patients was 8.1 percent while
in Japanese orthodontic patients the prevalence was
8.5 percent.14 The prevalence in Mexican orthodontic
patients was 2.7 percent.15
Karadas et al16 studied a Turkish subpopulation
for the distribution and frequency of tooth number
anomalies. They have reported that the agenesis of
maxillary lateral incisors in females (2.54%) were
higher as compared to the males (1.93%). There were
equal distribution of absent maxillary lateral incisors
between bilateral (1.13%) and unilateral (1.13%).
Difference between genders according to unilateral or
bilateral maxillary lateral incisors was not statistically
significant.
Current study examined 180 male and 184 female
from a total of 364 people. This study had found that
1.6% of subjects had missing maxillary lateral incisors, which was within the range of above mentioned
prevalence i.e. 0.3 to 10.1%.2,7,11,12,13,14,15 There was an
equal distribution of missing maxillary lateral incisors
within each gender i.e. (1.7%) in males and (1.6%) in
females (Table 3). All 6 missing lateral incisors were
unilateral. No bilaterally missing lateral incisors were
found among 364 subjects.
Limitation of the present study was small sample
size and wide range of age which was in contrast to the
studies mentioned before, which can have an impact
on the result as the actual prevalence of hypodontia
in the larger population may be different. The selection of limited age range could be the cause of higher
prevalence in previous studies. However the greater
age range (12-40 years) was selected for this study.
Most of the above mentioned studies have been
conducted in orthodontic population of patient which
is the reason of their high prevalence rate.7,11
The greater female to male ratio in previous studies
showed the more esthetic concern in the female population. In addition, differences between populations
of patients seeking treatment may possibly reflect
different psycho-social aspects between regions. It is
thus probable that in countries where smile aesthetics
are highly valued, maxillary lateral incisor hypodontia
Pakistan Oral & Dental Journal Vol 36, No. 2 (April-June 2016)
303
Frequency of missing maxillary lateral incisors
may motivate parents and patients to seek treatment.
The current study was carried out at the local
dental hospital setting. Therefore these results represent only the population who is visiting only specific
dental hospital, which is a source of bias. Nonetheless,
the results give some idea of the situation in the city
as a whole. Previous studies which have shown lower
percentage of population showing missing maxillary
lateral incisors probably because of these studies were
conducted on general population instead of orthodontic
patients only as well. For future studies a large sample
size from whole general population should be used to
obtain prevalence and overcome bias.
CONCLUSION
Following results has been obtained for prevalence
of missing maxillary lateral incisors.
4
Liu P-R, Ramp LC. Restoration of congenitally missing lateral
incisors after orthodontic treatment. Semin orthod 2013; 19(1):
49-52.
5
Cakan DG, Ulkur F, Taner T. The genetic basis of dental
anomalies and its relation to orthodontics. Eur J Dent. 2013
Sep; 7(Suppl 1): S143-7. doi: 10.4103/1305-7456.119092.
6
White SC, Pharoah MJ editors. Oral Radiology: Principles and
Interpretation. 6th ed. St Louis: Mosby; 2009. p298.
7
Durrania OK, Bashir U, Shamsher M. Prevalence of tooth
agenesis in orthodontic patients at Islamic International Dental
Hospital. PODJ. 2010; 2(2): 48-51.
8
Foater TD. Menezes DM: The assessment of Occlusal features
for public health planning purposes. Am J Orthod Dentofacial
Orthop 1976; 63: 83-90.
9
Fekonja A. Hypodontia in orthodontically treated children. Eur
J Orthod. 2005; 27: 457-60.
10 Kavadia S, Papadiochou S, Papadiochos I, Zafiriadis L. Agenesis
of maxillary lateral incisors: A global overview of the clinical
problem. Orthodontics (Chic) 2011; 12: 296-317.
• Prevalence for missing maxillary lateral incisors
which has been calculated was very low i.e. 1.6%.
11 Farhat Amin, SA. Agenesis and malformation of maxillary
lateral incisors in orthodontic patients, a study. Annals 2011;
17(4): 347-51.
• There was equal male to female ratio for missing
lateral incisors.
12 Al-Humayani F. Agenesis and malformation of maxillary lateral
incisors in Saudi Arabian female students. Egyptian dental
journal 2005; 51: 1-6.
• All permanent maxillary lateral incisors were
unilaterally absent.
13 Nordgarden H, Jensen JL, Storhaug K. Reported prevalence
of congenitally missing teeth in two Norwegian counties. Community Dent Health. 2002; 19: 258-61.
REFERENCES
14 Endo T, Ozoe R, Kubota M, Akiyama M, Shimooka S. A survey
of hypodontia in Japanese orthodontic patients. Am J Orthod
Dentofacial Orthop. 2006; 129: 29-35.
1
2
3
Anziani H1, Cole B, Hobson R. An unusual dental anomaly in
a hypodontia patient. Dent Update. 2010 Dec; 37(10): 691-2,
694-95.
Pushparaja Shetty AA , soniya Adyanthaya, Sreelatha SV. The
prevalence of hypodontia and supernumerary teeth in 2469
school children of the Indian population: an epidemiological
study. Indian J stomatol 2012; 3(3): 150-52.
Stevenson B, Patel D, Ricketts D, Cord A. The orthodontic-restorative interface in patients with hypodontia: the patient's
journey. Dent update 2013; 40(5): 354-60.
15 Silva Meza R. Radiographic assessment of congenitally missing
teeth in orthodontic patients. Int J Paediatr Dent. 2003; 13:
112-16.
16 Karadas M, Celikoglu M, Akdag MS. Evaluation of tooth number
anomalies in a subpopulation of the North-East of Turkey. Eur
J Dent 2014; 8: 337-41.
CONTRIBUTIONS BY AUTHORS
1 Farwa Batool:
2 Alia Ahmed:
3 Sharaz Ahmed:
4 Samara E Zahra:
Main author, designed the work, collection of data, statistical analysis and
interpretation of the data ,wrote the article
Statistical analysis, final approval of the version.
Reviewed the article.
Helped in data collection.
Pakistan Oral & Dental Journal Vol 36, No. 2 (April-June 2016)
304