|Year : 2020 | Volume
| Issue : 1 | Page : 1-8
Prevalence of selected dental anomalies among a sample of school children in Tanta
Amira Mostafa Mostafa, Nahed A. Abo Hamila, Ahmed E. El-Desoky
Department of Pediatric Dentistry, Faculty of Dentistry, Tanta University, Tanta, Egypt
|Date of Submission||19-Dec-2018|
|Date of Acceptance||03-Apr-2019|
|Date of Web Publication||20-Jun-2020|
Amira Mostafa Mostafa
Department of Pediatric Dentistry, Faculty of Dentistry, Tanta University, Tanta Governorate, 31527
Source of Support: None, Conflict of Interest: None
To determine the prevalence of selected developmental anomalies among a sample of Tanta school children.
Patients and methods
This study was conducted on 3020 healthy Egyptian children (1510 boys and 1510 girls) aged 8–14 years old. The children were selected from 94 primary and preparatory schools in Tanta between March 2016 and February 2017, and their teeth were examined clinically according to WHO criteria for oral health survey for presence of selected dental anomalies.
The total prevalence of anomalies was 20.36% as follow: hypodontia was 0.63%, hyperdontia was 0.3%, microdontia was 0.2%, peg shape lateral was 0.63%, cusp of carabelli was 5.5%, talon cusp was 0.23%, and gemination was 0.03%, enamel hypoplasia was 2.38%, demarcated opacities were 9.4%, diffuse opacities were 2.15%, transposition was 0.07%, and no cases of macrodontia, fusion, or dens invaginatus were detected in this study. There were no significant differences regarding sex or residence area except for peg shape lateral showed higher prevalence in rural areas (P < 0.05).
About fifth of children were affected by at least one anomaly which is comparable to other studies, dental anomalies may occur without relation to a disease or syndrome and dental anomalies nearly occur in both sexes equally.
Keywords: dental anomalies, school children, prevalence
|How to cite this article:|
Mostafa AM, Hamila NA, El-Desoky AE. Prevalence of selected dental anomalies among a sample of school children in Tanta. Tanta Dent J 2020;17:1-8
|How to cite this URL:|
Mostafa AM, Hamila NA, El-Desoky AE. Prevalence of selected dental anomalies among a sample of school children in Tanta. Tanta Dent J [serial online] 2020 [cited 2020 Jul 9];17:1-8. Available from: http://www.tmj.eg.net/text.asp?2020/17/1/1/287099
| Introduction|| |
Tooth development is a complex process that takes different stages and continues for long time after birth. Any interference with this normal process will result in developmental anomalies that may affect the number, size, shape, and structure of teeth and pattern of tooth eruption. These anomalies may be localized to single tooth or including systemic conditions, also they can occur in both primary and permanent dentitions ,.
The factors leading to these developmental anomalies can be either genetic factors such as inheritance, metabolic and mutations or environmental factors including physical, chemical and biological factors, or combination of both genetics and environmental factors .
Early detection of dental anomalies is important to prevent their complications as: malocclusion, cosmetic deformities, periodontal problems, caries, and difficulties during dental treatment, also the knowledge of the prevalence of dental anomalies is very important as it can provide valuable information for genetic studies and also helps in the understanding of differences among population and between various population groups ,.
There are many types of developmental anomalies such as anomalies in the number, size, shape, structure, and position of teeth. The anomalies of the number of teeth can be either decrease (hypodontia) or increase in the number (hyperdontia). On the other hand, anomalies of size can be in the form of microdontia, and macrodontia, while anomalies of shape include double teeth (fusion and gemination), talon cusp, peg shape lateral incisor and dens invaginatus .
Moreover, dental anomalies can also arise from changes in the three mineralized components of the tooth: enamel, dentin and cementum leading to structural abnormalities of the enamel and/or the gross form of a developing tooth. The developmental defects of enamel are classified under two main categories: enamel hypoplasia which is a quantitative defect of enamel, and enamel hypomineralization which is a qualitative defect which may be in form diffuse or demarcated opacities ,.
Finally, any changes in the pattern of tooth eruption can lead to dental anomalies such as tooth transposition in which there is an exchange of position between two adjacent teeth .
There are many epidemiological studies on developmental dental anomalies have been conducted worldwide showing geographic and ethnic variation in their prevalence which ranges from 4.74 to 74% ,,,. Unfortunately, there are only few studies have been conducted in Egypt, so the present study is intended to determine the prevalence of selected developmental anomalies among a sample of Tanta school children.
| Patients and Methods|| |
Observational descriptive cross-sectional design was adopted in this study.
The study setting
The study was done among 3020 healthy Egyptian children, aged 8–14 years, at primary and preparatory (public and private) schools in Tanta between March 2016 and February 2017.
Sample size selection
The sample size was calculated using Epi info software created by WHO and Centers for Disease Control and Prevention (CDC), and the size of sample was found to be more than 400 based on 95% confidence level. Sample size was increased to 3020 to improve validity of results and to enable the study to detect more dental anomalies.
Multistage sample was selected for this study; it was selected on the basis of ease of accessibility. First the center and 23 villages were selected, then total of 94 primary and preparatory schools were selected from these areas, then from each school only one class was selected from third to sixth grade in primary and from first and second grade in preparatory schools of both sexes, then from each class about 30–35 children were selected for the examination.
Children with any medical history such as Down's syndrome, ectodermal dysplasia, cleft lip and cleft palate and Cleidocranial Dysostosis were excluded from the study.
Approval for this study was obtained from Research Ethics Committee at Faculty of Dentistry, Tanta University, Ministry of Education, Education affairs and school authorities. Informed consent/ascent to examine the children were taken from parents and their children after sending letters to explain the aim of the study according to the guidelines of Research Ethics Committee at Faculty of Dentistry, Tanta University.
Clinical examination and data collection
The students were informed about the purpose of the study and their teeth were examined by the same examiner (author) according to WHO criteria for oral health survey , and the diagnosis was based only on clinical examination using the following criteria :
- Hypodontia: student had clinical missed permanent teeth with no history of tooth extraction or trauma, or prolonged retention of primary tooth .
- Supernumerary tooth: a tooth which present in addition to the normal dentition.
- Macrodontia: a tooth that is substantially larger than average normal size or to the contra lateral tooth .
- Microdontia: a tooth that is much smaller than the average normal size, or its contra lateral tooth .
- Gemination and fusion: two teeth appear to be united because of division of a tooth germ or union of two germs. In case of fusion, there will be one less tooth in the arch than normal, while in gemination, the total number of teeth is normal, when the affected tooth is counted as one.
- Talon cusp: a prominent accessory cusp-like structure projecting incisally from the cingulum area of an incisor.
- Carabelli cusp: a characteristic morphological anomaly (cusp prominence) on the mesiopalatal surface of the upper first permanent molars.
- Peg-shaped lateral incisor: any upper lateral incisor with a reduction in its mesio-distal size in a gingivo-incisal direction.
- Dens invaginatus: an invagination of enamel in the crown of the tooth.
- Enamel hypoplasia: a quantitative defect of enamel clinically identified as grooved or pitted enamel with reduced thickness while the surface hardness is normal, it may be localized defect or generalized defect .
- Enamel hypocalcification. Demarcated opacity: enamel of normal thickness and intact surface, with alteration in the translucency of the enamel. It is demarcated from the adjacent normal enamel with a clear boundary and can be white, cream, yellow or brown in color. Diffuse opacity: an alteration in the translucency of the enamel, white in color with no clear boundary between the adjacent normal enamel .
- Tooth transposition: the positional interchange of two adjacent teeth.
| Results|| |
The results of the present study revealed that dental anomalies were found in 615 children representing 20.36% of the study sample, 19.36% have only one anomaly while 1% has more than one anomaly.
The prevalence of hypodontia was 0.63%, hyperdontia was 0.3%, microdontia was 0.2%, peg-shape lateral was 0.63%, cusp of carabelli was 5.5%, talon cusp was 0.23%, and gemination was 0.03%, enamel hypoplasia was 2.38%, demarcated opacities were 9.4%, diffuse opacities were 2.15%, transposition was 0.07%, and no cases of macrodontia, fusion, or dens invaginatus were detected in this study.
[Table 1] demonstrates distribution of dental anomalies among males and females, there were no significant differences between both sexes concerning all dental anomalies.
[Table 2] demonstrates distribution of dental anomalies among urban and rural areas. There were no significant differences regarding residence area except for peg-shape lateral which showed higher prevalence in rural areas (P < 0.05) [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6] [Figure 7] [Figure 8], [Figure 9], [Figure 10].
|Table 2: Distribution of dental anomalies according to area of residence|
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|Figure 1: Clinically bilateral missed upper lateral incisors in 13 years old female.|
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|Figure 5: Gemination in upper left central incisor in 13 years old female.|
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|Figure 9: Multiple anomalies in 12 years old female. Black arrow showing demarcated opacity in upper right incisor. Red arrow showing peg-shaped upper lateral incisor. White arrow showing retained lower deciduous incisor.|
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|Figure 10: Transposition between lower right lateral incisor and lower right canine in 13 years old female.|
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| Discussion|| |
Although the prevalence of dental anomalies has been performed by many researchers in different populations, there is no published study in Tanta yet. For this reason, Tanta was chosen as the geographical area of the study, thus providing baseline data about the prevalence of broad range of dental anomalies and their distribution in accordance with sex and residence area.
The age group selected for this study was 8–14 years old, since in persons of mid-teen age and above, the chances of misdiagnosis of some anomalies increase because some teeth may be lost as a result of caries and trauma or extracted as part of orthodontic treatment ,. This study was carried out at schools, thus increasing the chances of including children free from any syndromes to avoid their association with dental anomalies, also allowing access to children of different socioeconomic status giving methodological strength for the study.
This study respected the clinical examination only since there is no radiographs equipment was available, and no legal obligation to take radiographs in the dental health surveying held at the schools . The (American Dental Federation) FDI technical reports suggested that congenitally missed and supernumerary teeth can be studied without the use of radiographs .
The overall prevalence of dental anomalies was 20.36% in the present study. This result disagreed with Garib , and Hagiwara et al.  who reported different prevalence of dental anomalies in their clinical studies among school students (40.2 and 4.82%, respectively). These different results may be attributed to different types of anomalies evaluated in each study and to racial differences.
In the present study, the prevalence of hypodontia was 0.63%, this result approximated the results of Basalamah and Baroudi  and Guttal et al.  who reported that the prevalence of hypodontia was 0.4 and 0.3%, respectively. In contrary, Montasser and Taha  reported prevelance of 2.36% for hypodontia in Egypt. Also the systematic review by Khalaf et al.  revealed that the overall prevalence of hypodontia was 6.4% worldwide. These different results may be attributed to differences in study pattern and examination technique, as this clinical study was directed toward school children, whereas some other researchers studied dental anomalies among orthodontic patients using radiographs or including third molar in their studies.
In this study females showed higher prevalence of hypodontia when compared to males without significant difference. This finding agreed with Polder et al. , Khalaf et al. , Acev and Gjorgova , and Serour and Abu Affan , who reported that hypodontia is more common in females.
The prevalence of supernumerary teeth in this study was 0.3%. This result agreed with several studies ,,,, who documented that the prevalence of hyperdontia ranged between 0.2 and 0.38%. On the other hand, studies by Montasser and Taha , Diab , Kathariya et al. , and Lotfy , revealed higher prevalence of supernumerary teeth than this study, this may be attributable to that radiographs were not used in this investigation, therefore it was unable to confirm presence of impacted supernumerary teeth with no signs of eruption. Males showed higher prevalence of supernumerary teeth when compared to females with no statistically significant difference. This finding is in agreement with Osuji and Hardie , Berrocal et al.  and Küchler et al. .
In the present study, no cases of macrodontia were recorded. This result agreed with Şener et al.  who published that no cases of macrodontia were present in their study. On the other hand, this finding disagreed with Kathariya et al.  and Yassin  who reported that prevalence of macrodontia was 1.3 and 1.8%, respectively. These different results may be attributed to genetic and racial factors.
The prevalence of microdontia was 0.2% in this study, this result approximated the result of Temilola et al.  who reported that microdontia was 0.1%. On contrast, this result disagreed with Kathariya et al. , Vibhute et al. , and Ramdurg et al. , who reported higher prevalence of microdontia (4.3, 7.7, and 5.7%, respectively). These different results may be attributed to quietly large sample size in this study which exceeded that of aforementioned studies, and to different diagnostic criteria as these studies considered peg lateral as microdont tooth, while in the present study, peg lateral was considered as an isolated anomaly.
In the present study the overall prevalence of peg shape lateral incisor was 0.63%. This result agreed with studies done by Salama and Abdel-Megid  and Fujita et al. , they recorded that prevalence of peg shape lateral was 0.7%. On contrary, this finding disagreed with Montasser and Taha , and Hua et al. who reported higher prevalence of 1.96 and 1.8%, respectively. This may be attributed to different study groups as the present study was directed toward healthy school children.
In the present study, females showed slightly higher prevalence of peg-shaped lateral incisor than male with no statistically significant difference. Kabbani et al.  agreed that peg-shaped lateral incisors occurred in females more than males as recorded in this study, while Lotfy  reported that males are more affected that females. This may be attributed to different sample size of the examined groups. Also, in the present study, rural areas revealed significant higher prevalence of peg-shape lateral incisors, this may be attributed to genetic and environmental factors.
In the present study, cusp of carabelli represented 5.5% of the study sample. This result disagreed with other studies done by Raščić et al. , Al Shethri , and Kirthiga et al.  who reported that the prevalence of cusp of carabelli was 23, 33.5, and 19.5%, respectively. These differences may be attributed to different diagnostic criteria as in this study only cusp prominence was considered while in the previous studies even the shallow furrows on mesio-lingual cusp of upper first molars were considered as an anomaly. Males showed higher prevalence of cusp of carabelli when compared to females with no statistically significant difference. This result disagreed with Falomo , while Niazi et al.  and Subedi et al.  who reported higher prevalence in females, this may be attributed to different sample size of the examined groups.
In the present study, talon cusp represented only 0.23% of the study sample, close results of 0.29% and 0.2% were recorded by Sreeshyla  and Nayak and Nayak , respectively. This result disagreed with Hamasha and Safadi  who detected that prevalence talon cusp was 2.4% using radiographic examination alone which may be misleading, while this study depended on clinical examination which is more reliable in talon cusp detection. Also higher prevalence of 4.28% was reported by Guttal et al. , this may be attributed to genetic factors, and to different diagnostic criteria as in this study only projections that extend at least half distance from CEJ to the incisal edge were considered as talon cusp. Males and females showed equal distribution of talon cusp in this study, while Cho et al.  and Sreeshyla  reported that females were more affected than males. This may be attributed to different sample size in the examined groups.
Regarding double teeth, only one case of gemination was present in a female rural resident student representing prevalence of 0.03%. This rare occurrence of gemination is in a line with Altug-Atac and Erdem , and Hagiwara et al.  who reported the prevalence of gemination was 0.07 and 0.01%, respectively. Also, other researchers as Aljazi and Abdullah , Santosh et al. , Herrera-Atoche et al. , and Temilola et al.  reported no cases of gemination in their studies. On contrast, this result disagreed Ardakani et al. , Bunyarit et al. , and Luke et al.  who reported higher prevalence of gemination as 2.1, 0.5, and 1.1%, respectively.
There were no cases of fusion were recorded in this study, this finding agreed with Bäckman and Wahlin , Aljazi and Abdullah , Montasser and Taha , Santosh et al. , and Temilola et al. who reported that no cases of fusion were found in their studies, while disagreed with Guttal et al. , Vibhute et al. , and Yassin  who reported that prevalence of fusion was 4.85, 0.9, and 0.8%, respectively. This higher prevalence of double teeth may be attributed to different study pattern as this study only includes permanent teeth in healthy school children and to different sample size of examined groups.
No cases of dens invaginatuis were recorded in this study, this is similar to Temilola et al.  in Nigeria, and in a close relation to Sreeshyla  study in India who reported that prevalence of dens invaginatus was 0.02%. Nevertheless other studies from Iran showed higher prevalence of 1.44 and 10.9% as documented by Ghabanchi et al. , and Dalili et al. , respectively, and in Jordan, the prevalence was 2.95% by Hamasha and Alomari . These higher results may be attributed to different methodology, as they used radiographs in their studies among patients.
In the present study the overall prevalence of enamel defects was 13.95%. This result disagreed with Hawas , and with Al-Sheraydah and Al-Dahan  who published that prevalence of enamel defects in permanent teeth was 38.9 and 30.5%, respectively. These differences may be attributed to different sample size of the examined groups and different indices used in diagnosis.
Enamel hypoplasia was 2.38% in the present study, this result approximated the results of Raščić et al. , and Basalamah and Baroudi  who reported that the prevalence of enamel hypoplasia was 2 and 2.8%, respectively, while disagreed with Robles et al.  and Abdullah  who recorded that the prevalence of enamel hypoplasia was 0.8 and 9.04%, respectively. This may be attributed to different ethnic groups with different nutrition and different local factors as abscess or local trauma to the predecessor primary tooth . On the other hand, the prevalence of enamel hypocalcification was 11.5%. This finding disagreed with Raščić et al. , and Hawas  who reported that the prevalence of enamel hypocalcification was 7 and 34.3%, respectively. These different results may be attributed to different indices used in diagnosis and different sample size.
Additionally, in the present study, the prevalence of enamel hypocalcification was more prevalent than hypoplasia, these finding in a line with Raščić et al. , Nayak and Nayak , Hawas , and Robles et al. who agreed that enamel hypocalcification was more prevalent than hypoplasia. This may be attributed to that enamel hypoplasia associated with environmental disturbances during the short secretory stage, while enamel hypocalcification associated with environmental disturbances during transitional and maturational stage which occupy longer time in amelogenesis process ,.
Regarding all enamel defects, there is no significant difference was found in relation to sex or residence area; this is in agreement with Shiu-Yin et al. , Hawas , and Hamdan  who found that enamel defects were equal in males and females, while disagrees with Basha et al.  who found that enamel defects were more common in males than females, also disagree with Hamdan  who found that the prevalence of enamel defects was higher in rural areas.
Finally, the prevalence of transposition was recorded as 0.07% in the present study, this result agreed with Küchler et al. , and Hatzoudi and Moschos  who stated that the prevalence of transposition was 0.08 and 0.09%, respectively. In contrary, Moschos et al.  showed that tooth transposition has a mean prevalence of 0.33% worldwide, this may be attributed to different study groups, different sample size and racial differences.
This study had some limitations in detection of dental anomalies that could be present within the bone such as supernumerary teeth and hypodontia, also diagnosis of microdontia and macrodontia depended on visual examination without measuring the dimensions of teeth on casts.
| Conclusion|| |
- About fifth of children were affected by at least one anomaly which is comparable to other studies.
- Dental anomalies may occur without relation to a disease or syndrome.
- Dental anomalies nearly occur in both sexes equally.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10]
[Table 1], [Table 2]