articol-yovcheva-2017
ORO-DENTAL PREVENTION
PREVALENCE OF MALOCCLUSIONS IN A SAMPLE OF 4-5-YEAR-OLD BULGARIAN
General
CHILDREN
Keti Yovcheva1a*, Miroslava Yordanova1b, Svetlana Yordanova1c, Nina Musurlieva2d
¹Department of Orthodontics, Faculty of Dental Medicine, Medical University – Plovdiv, Bulgaria
²Department of Social Medicine and Public Health, Faculty of Public Health, Medical University – Plovdiv, Bulgaria
a
DMD
b
DMD, PhD
c
DMD, PhD
d
DMD, PhD
Received: October 11, 2016
Revised: November 14, 2016
Accepted: November 29, 2016
Published: December 01, 2016
Academic Editor: Ioan Danilă, DDS, PhD, Professor,“Gr. T. Popa” University of Medicine and Pharmacy Jassy, Jassy, Romania
Cite this article:
Yovcheva K, Yordanova M, Yordanova S, Musurlieva N. Prevalence of malocclusions in a sample of 4-5-year-old Bulgarian children. Stoma Edu J.
2017;4(1):66-71.
ABSTRACT DOI: 10.25241/stomaeduj.2017.4(1).art.7
The aim of this study is to estimate the prevalence of malocclusions in a sample of 4-5-year-old
children.
Methodology: 471 boys and girls participated in this observational cross-sectional epidemiological
study. The presence of spacing, no spacing and crowding, anteroposterior, transverse and vertical
occlusion relationships was assessed and analyzed.
Results: Normal occlusal relationships were found in 35.6% of all children. Generalized spacing was
found in 78.2% of the subjects, followed by no spacing in 16.1% and crowding in 5.7%, respectively.
Class I canine relationship was found in 64.1% of the children, followed by Class II in 29.1% and
Class III in 9.6%. A flush terminal molar relationship was found in approximately 70% of the children,
followed by mesial and distal molar relationships equally distributed. An increased and decreased
overjet was observed in 9.5% and in 4.9% of the children. An anterior cross-bite was documented in
6.4% of all the examined children. An unilateral posterior cross-bite and a bilateral posterior cross-
bite were observed in 3.2% and in 1.5% of the sample. A posterior edge-to-edge bite was found in
1.9%. A normal overbite was found in 30.1% of all children; a deep bite with and without gingival
contact was registered in 27% and in 8.5% respectively; an anterior open bite was seen in 7.2% of
the children and a posterior open bite in 1.3%. The percentage of mandible lateral deviation cases
is 2.5%.
Conclusion: Due to the high prevalence of malocclusions with 64.4%, early attention may be given
to orthodontic prevention measures.
Keywords: cross-sectional study, occlusal relationship, prevalence, prevention, malocclusions.
1. Introduction are not regularly registered and analyzed. An
The last study conducted on the prevalence of optimal occlusion in primary dentition is essential
malocclusions in primary dentition in Bulgaria was for the further development of the occlusion in the
in the middle of the 80’s, where almost all of the permanent dentition.3,4,5,6 The current preventive
children were included in organized contingents program for the Bulgarian children is mostly
and strictly examined by a dentist or an orthodontist orientated to caries prevention and according to
every year. At that time an oral health prevention literature, caries-reducing measures are not likely
program was developed, which included to have a significant influence on the formation of
orthodontic services for the masses.1,2 After the malocclusions in primary dentition.7
change in health politics, this program is no longer We need some present-day data about the
active and occlusal characteristics, prevalence and prevalence of malocclusions in primary dentition
the types of malocclusions in the primary dentition and the aim of this study is to estimate dental
*Corresponding author:
Dr. Keti Yovcheva, DMD, Department of Orthodontics, Faculty of Dental Medicine, Medical University – Plovdiv, av. Hristo Botev 3, Plovdiv 4000, Bulgaria
Tel/Fax: +359.889.623.842 / +35. 932.631.651, e-mail: drketiyovcheva@gmail.com
66 Stoma Edu J. 2017;4(1):66-71. http://www.stomaeduj.com
PREVALENCE OF MALOCCLUSIONS IN A SAMPLE OF 4-5-YEAR-OLD BULGARIAN CHILDREN
health, prevalence of malocclusions and orofacial We have distinguished correct lateral occlusal
General
dysfunctions in a sample of 4-5-year-old Bulgarian relationships, a unilateral and a bilateral cross bite,
kindergarden children. a posterior edge-to-edge bite and a scissor bite.
An occlusion of the incisal edges was assessed
2. Methodology as an anterior edge-to-edge bite. An overbite
The subjects were randomly selected from was graded according to the coverage of the
different kindergardens in the city of Plovdiv. mandibular incisor by the most protruded
Inclusion criteria were the existence of fully maxillary incisor. A normal one, when up to half of
developed primary dentition, no orthodontic the mandibular incisor is covered by the maxillary
treatment, Caucasian origin and a parental incisor. An increased overbite, when more than
consent for participation in the study. A total of 471 half of the mandibular incisor is covered by the
boys and girls participated in this cross-sectional maxillary incisor. An overbite with gingival contact
epidemiological study. The study was approved by was recorded when the mandibular incisor was
the Ethics Committee of the Medical University – fully covered by the maxillary incisor and there was
Plovdiv (Р-7781). a contact of the incisal edge with the gingiva. An
A postgraduate student in Orthodontics carried out absence of a vertical overlap of the lower incisors
the entire diagnostic assessment of all the children. was described as an anterior open bite and
A specific form was designed for the purpose of divided into two groups: moderate (<3mm) and
this study which contains information about dental severe (>3mm).
health, individual occlusion findings and functional Collection, evaluation and a statistical analysis of
status. All the findings were made under good the data were conducted using Microsoft® Excel
lighting conditions. The metric parameters were and SPSS Version 17.0 for Windows® (SPSS Inc.,
recorded by using a metal ruler marked in 0.5 Chicago, IL., USA). Means and standard deviations
mm. In this paper, all the orthodontic findings will were determined as descriptive statistical values
be described and the following parameters have in order to characterize univariate frequency
been selected and analyzed: distributions of various variables. A comparison of
The type of primary dentition was assessed as absolute frequencies of specific characteristics was
follows: with generalized spaces between the tested with Pearson’s chi-square test. The statistical
teeth and localized spaces (Type 1), no spaces significance was assessed at the 5% level.
(Type 2) or a crowded dentition (Type 3).
The overjet was measured in mm as a distance 3. Results
between the labial surface of the lower and upper A total of 241 males and 230 females were
incisors. A distance of (0-3 mm) was defined as a examined. Normal occlusion relationships were
normal distance. An increased overjet was divided found in 35.6% of the sample. 126 or 26.8% of the
into two groups (3-6mm) and (>6mm), and a children have one malocclusion, followed by 129
negative overjet (<0mm), all measured in mm. children or 27.4% with two malocclusions, 27 or
An anterior cross-bite was registered when one 5.7% with three malocclusions and then 21 or 4.5%
or more maxillary incisors or canines occluded with four malocclusions. The total distribution of
lingually to the mandibular incisors or canines. malocclusions is 64.4%.
The criteria described by Foster & Hamilton8 were The most prevalent type of primary dentition is Type
used for the primary canine and molar relationship 1 with 78.2 % (with spacing), followed by 16.1%
assessment. Type 2 (no spacing) and 5.7% Type 3 (crowding).
• Class I - the tip of the maxillary primary canine The gender comparison is shown in Table 1. There
tooth is in the same vertical plane as the distal of is a statistically significant difference between girls
the mandibular primary canine and boys in the distribution of spacing, no spacing
• Class II - the tip of the maxillary primary canine and crowding which is more prevalent in girls
tooth is anterior to the distal surface of the (with spacing χ2=13,308, no spacing χ2= 10,429,
mandibular primary canine. crowding χ2= 5,318).
• Class III - the tip of the maxillary canine is The prevalence of overjet is shown in Table 2. A
posterior to the distal surface of the mandibular total of 85.6% of all the children have a normal
primary canine. overjet, 8.7% an increased overjet, 0.8% an
Terminal plane relationships of the second primary excessive overjet and 4.9% a decreased overjet.
molar: Gender and age comparison of the normal,
• Flush terminal - The distal surfaces of the upper increased and decreased overjet among 4 and
and lower second primary molars are in the same 5-year-old boys and girls revealed no statistically
anteroposterior level. significant differences. An anterior cross-bite
• Mesial step - the maxillary terminal plane is was registered in 6.4% of all the children without
posterior to the mandibular terminal plane significant differences in age and sex.
• Distal step - the maxillary terminal plane is The distribution of different sagittal relationships
anterior to the mandibular terminal plane. of primary canine and second primary molars is
Molar and canine occlusions for each child were shown in Table 3 and respectively in Table 4. A
recorded separately for the left and the right sides neutral occlusion of the primary canines was found
of the dentition. in 60 % of all children, a distal occlusion in 30%
Stomatology Edu Journal 67
PREVALENCE OF MALOCCLUSIONS IN A SAMPLE OF 4-5-YEAR-OLD BULGARIAN CHILDREN
Table 1. Prevalence of spacing, no spacing and crowding in primary dentition.
General
Gender Type 1 Type 2 Type 3 Total
Girls 172 (74.8%) 50 (21.7%) 8 (3.5%) 230 (100%)
Boys 196 (81.3%) 26 (10.8%) 19 (7.9%) 241 (100%)
Total 368 (78.2%) 76 (16.1%) 27 (5.7%) 471 (100 %)
Table 2. Prevalence of normal, increased and decreased overjet in 4- and 5-year old children.
Age Overjet 0-3mm Overjet 3-6 mm Overjet >6 mm Overjet < 0 mm Total
4 years 138 (87.9%) 10 (6.4%) 2 (1.3%) 7 (4.5%) 157 (100%)
5 years 265 (84.4%) 31 (9.9%) 2 (0.6%) 16 (5.1%) 314 (100%)
Total 403 (85.6%) 41 (8.7%) 4 (0.8%) 23(4.9%) 471 (100 %)
Table 3. Primary canine sagittal relationships.
Class I Class II Class III
Age Total
Right Left Right Left Right Left
92 102 45 37 20 18 157
4 years
(58.6%) (65.0%) (28.7%) (23.6%) (12.7%) (11.5%) (100%)
181 187 103 100 30 27 314
5 years
(57.6%) (59.6%) (32.8%) (31.8%) (9.6%) (8.6%) (100%)
273 289 148 137 50 45 471
Total
(58.0%) (61.4%) (31.4%) (29.1%) (10.6%) (9.6%) (100 %)
Table 4. Second molar sagittal relationships.
Flush terminal Mesial step Distal step
Age Total
Right Left Right Left Right Left
117 119 21 19 19 19 157
4 years
(74.5%) (75.8%) (13.4%) (12.1%) (12.1%) (12.1%) (100%)
213 222 52 43 51 47 314
5 years
(67.8%) (70.7%) (16.6%) (13.7%) (16.2%) (15.0%) (100%)
330 341 73 62 70 66 471
Total
(70.1%) (72.4%) (15.5%) (13.2%) (14.9%) (14.0%) (100 %)
and a mesiocclusion in 10 %. A distribution of a children (27.0%) and a deep overbite with gingival
flush terminal molar relationship in percentages contact in 40 children (8.5%). Statistically significant
is 70.1% on the right side and 72.4% on the left was the fact that boys showed more deep bites
side of the examined subjects. The mesial step was with gingival contact (χ2 = 3.347, p = 0.067) and
assessed as 15.5% on the right side and 13.2% on also the difference between the age groups was
the left side. And the distal step was assessed as statistically significant (χ2 = 3.497, p = 0.061) - an
14.9% on the right side and respectively 14% on increase of the frequency was observed with the
the left side. There are no statistically significant increasing of the age.
differences between gender in the primary canine A unilateral posterior cross-bite was observed
relationships and the second primary molar in 3.2% of the sample and a bilateral posterior
relationships. But we found a statistically significant cross-bite in 1.5%. An edge-to-edge bite in
increase in Class II canine relationships between the posterior region was found in 9 cases with a
the age groups (χ2 = 3.479, p = 0.062). statistically significant difference in age comparison
A normal overbite was found in 30.1% of the (χ2 = 8.156, p = 0.004), the 4-year-olds showed
sample and an anterior edge-to-edge bite more edge-to-edge bites than the 5-year-olds. In
existed in 27.2% of all the children, with no this sample, a scissor bite was not registered. The
significant differences between gender and age total percentage of mandible lateral deviation was
in the subgroups. A moderate anterior open bite 2.5%. A mandible deviation to the right side was
(<3mm) and a severe anterior open bite (>3mm) found in two cases and 10 cases to the left side.
were registered respectively in 6.8% and 0.4%. The percentage prevalence of malocclusions in
A posterior open bite was documented in 1.3% primary dentition is shown in Table 5.
of all children. A deep overbite was found in 127
68 Stoma Edu J. 2017;4(1):66-71. http://www.stomaeduj.com
PREVALENCE OF MALOCCLUSIONS IN A SAMPLE OF 4-5-YEAR-OLD BULGARIAN CHILDREN
Table 5. Percentage prevalence of malocclusions in primary dentition.
General
Type of malocclusion Children with malocclusion Percentage (%)
Class II canine occlusion 142 30.1%
Class III canine occlusion 45 9.6%
Anterior open bite 34 7.2%
Posterior open bite 6 1.3%
Deep overbite 127 27%
Deep overbite with gingival contact 40 8.5%
Anterior cross bite 30 6.4%
Unilateral - 15 3.2%
Posterior cross bite
Bilateral - 7 1.5%
Posterior edge-to-edge bite 9 1.9%
Mandible lateral deviation 12 2.5%
4. Discussion findings of Müssig.15 An anterior cross-bite was
The overall prevalence of malocclusions is high observed in 6.4% of the sample, which resembles
- 64.4%. According to the scientific literature, the a study conducted by Kerouso20 for the Finnish
prevalence of malocclusions in primary dentition children.
varies from 22% to 93%9,10 due to racial characteristics The prevalence of a normal overbite is 30.1%. We
and different occlusion recording methods. We also found 27.2% of an anterior edge-to-edge bite
found a higher prevalence of malocclusions as and, at the age of 5, it is a norm according to Hotz.21
compared to some previous studies conducted on The findings are in agreement with the results by
the Bulgarian population by Nikolov & Atanasov,11 Nanda et al.,16 Müssig15 and Berneburg et al.14 But
who found 44.5% prevalence. The difference in on the other hand, the high frequency may be due
prevalence is probably due to the fact that at that time to the self-correction of an anterior open bite after
a mass orthodontic prevention program was held. interrupting the action of external factors.22 In this
The generalized spacing in this sample is 78.2% and it sample, a moderate anterior open bite(<3mm) and
is corresponding to the findings of Foster&Hamilton8 a severe anterior open bite (>3mm) were registered
with 70%. The prevalence of no spacing and respectively in 6.8% and 0.4% of the children, which
crowding concurs with other studies,4,12,13 but it is is in agreement with Berneburg et al.,14 who found
much lower than the results for the British children.8 4.6% prevalence of an anterior open bite. The
Our results for the prevalence of several concurrent prevalence of an anterior open bite in this sample
malocclusions in primary dentition are in agreement is significantly less than the findings of Müssig15 and
with other studies.14 The canine sagittal relationships Tschill et al.4
showed that 60% of the children have Class I, 30% Our results showed prevalence of a deep bite and
have Class II and 10% have Class III and the results a deep bite with gingival contact, 27% and 8.5%,
are corresponding to the findings for the European respectively, which is similar to the studies done
population.4,10,15 by Müssig15 and Grabowski et al.10 In this sample,
Our study conducted on the Bulgarian population boys have more severe deep bites and there is also
showed a percentage distribution of a flush terminal a statistically significant increase in prevalence of a
molar relation in 70.1% of the subjects on the right deep bite with gingival contact with the increasing
side and 72.4% on the left, which is similar to studies of the age, which concurs with other studies’
done by Nanda et al.16 A mesial step and a distal results,10,22 but it is in disagreement with the results of
step in this sample are equally distributed in 14.4% Berneburg et al.14 A posterior cross-bite was seen in
and 14.5%, respectively. Our results for the mesial 4.7% and a posterior edge-to-edge bite in 1.9% of all
step are in agreement with the findings of Baume17 the children in this study.
and Ravn,18 but in disagreement with the results of Other investigators report that a deciduous posterior
Johannsdottir et al.,19 who found that 60% of their cross bite ranges between 7-12%.8,10,18 But our
sample had mesial step occlusal relationships in findings are similar to Hensel (12) and Stahl &
primary dentition. Our results for the distal step are Grabowski,6 who report 5.1% and 4% respectively.
similar to the findings by Grabowski et al.,10 who Available literature suggests that the development of
found 15.5% “distalization” in primary dentition. the occlusion and oral functions in primary dentition
The normal overjet is in agreement with the results is a continuum for the further morphological and
by Berneburg et al.,14 but the increased overjet was functional development of the stomatognathic
assessed in 9.5% of this sample, which is lower than system.4,10 The correct development of a stable,
their findings. Our results for the decreased overjet functional and aesthetically acceptable occlusion
are higher than other studies10,14 but similar to the is an integral component of a comprehensive oral
Stomatology Edu Journal 69
PREVALENCE OF MALOCCLUSIONS IN A SAMPLE OF 4-5-YEAR-OLD BULGARIAN CHILDREN
health care for all pediatric dental patients.23 Further relevant malocclusions in our study.
General research is needed to establish the development of Due to the high prevalence of malocclusions in
the dentition and malocclusions in the next stages deciduous dentition, it is necessary for children to be
of the dental development in this sample, and the regularly examined at an early age and the occlusal
relatively small sample size is a limitation of our study. development should be individually assessed.
Early attention may be given to malocclusions and
5. Conclusions their prevention, and especially to those caused
This cross sectional study provides present-day data by external etiologic factors like bad habits and
about the prevalence of malocclusions in a sample incorrect oral functions.
of 471 Bulgarian children with primary dentition.
Statistical differences in the type of dentition, a deep Acknowledgments
bite with gingival contact and a posterior edge-to- The authors declare no conflict of interest related
edge bite were found. Class II canine occlusion, a to this study. There are no conflicts of interest and no
distocclusion, a deep bite, no spacing and crowding financial interests to be disclosed.
and an increased overjet were the epidemiologically-
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70 Stoma Edu J. 2017;4(1):66-71. http://www.stomaeduj.com
PREVALENCE OF MALOCCLUSIONS IN A SAMPLE OF 4-5-YEAR-OLD BULGARIAN CHILDREN
General
Keti YOVCHEVA
DDS, PhD, Postgraduate Student
Department of Orthodontics
Faculty of Dental Medicine
Medical University - Plovdiv, Bulgaria
CV
Dr Keti Yovcheva, DDS is a PhD and postgraduate student at the Department of Orthodontics, Faculty of
Dental Medicine, in Medical University - Plovdiv, Bulgaria. Since 2010 she has been working as an assistant
doctor at a private orthodontic practice. One of her main research interest is preventive and interceptive
orthodontics.
Questions
Which is the most prevalent type of primary dentition found in this study?
q a. Type 1;
q b. Type 2;
q c. Type 3;
q d. none of them.
What is the total prevalence of malocclusions found in this study?
q a. 54.4%;
q b. 64.4%;
q c. 74.4%;
q d. 82.5%.
What is the prevalence of anterior open bite found in this study?
q a. 5.8%;
q b. 6.0%;
q c. 6.4%;
q d. 6.8%.
What is the prevalence of unilateral posterior cross bite found in this study?
q a. 4.5%;
q b. 4.2%;
q c. 3.2%;
q d. 3.0%.
Stomatology Edu Journal 71