Archives of Medicine and Health Sciences

ORIGINAL ARTICLE
Year
: 2019  |  Volume : 7  |  Issue : 2  |  Page : 172--176

Prevalence and distribution of dental agenesis among orthodontic patients of Kathmandu, Nepal


Sanjay Prasad Gupta1, Shristi Rauniyar2,  
1 Department of Dentistry, Orthodontics and Dentofacial Orthopedics Unit, Tribhuvan University Teaching Hospital, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal
2 Dental Villa-Orthodontic Center and Speciality Dental Clinic, Kathmandu, Nepal

Correspondence Address:
Dr. Sanjay Prasad Gupta
Department of Dentistry, Orthodontics and Dentofacial Orthopedics Unit, Tribhuvan University Teaching Hospital, Institute of Medicine, Tribhuvan University, Maharajgunj, Kathmandu
Nepal

Abstract

Background: Tooth agenesis is the most common developmental dental anomaly in humans with a wide variability of distribution among different population. Objective: The objective of this study was to find out the prevalence of dental agenesis among Nepalese orthodontic patients of Kathmandu and its occurrence with relation to gender, sides, and jaw. Materials and Methods: This study consisted of 601 patients (242 males and 359 females) aged between 10 and 35 years who require orthodontic treatment. Dental panoramic radiographs were evaluated for dental anomalies causing disturbance in number by a trained observer who followed a preestablished protocol. Chi-square test was used to determine the difference in the prevalence of dental agenesis between genders, sides, and jaws. Results: The prevalence of dental agenesis was 7.48% (45) while excluding the third molar and 27.62% (166) while including the third molar. The prevalence of oligodontia was 0.33% (2). The total number of missing teeth including the third molar was 371 and it was 72 while excluding the third molar. Maxillary lateral incisor was the most lost (48.61%) followed by mandibular lateral incisor (19.44%), mandibular central incisor (8.33%), mandibular second premolar (6.94%), and maxillary second premolar (5.55%) while excluding the third molars. There was no statistically significant difference in the prevalence of missing teeth in between gender (P = 0.996), in between right and left sides (P = 0.590), and in between upper and lower jaws (P = 0.010). Conclusion: The most common missing teeth were maxillary lateral incisor followed by mandibular lateral incisor, mandibular central incisor, and mandibular second premolar. Orthodontists have the responsibility to observe each patient carefully for dental agenesis and have full knowledge to plan the best possible treatments.



How to cite this article:
Gupta SP, Rauniyar S. Prevalence and distribution of dental agenesis among orthodontic patients of Kathmandu, Nepal.Arch Med Health Sci 2019;7:172-176


How to cite this URL:
Gupta SP, Rauniyar S. Prevalence and distribution of dental agenesis among orthodontic patients of Kathmandu, Nepal. Arch Med Health Sci [serial online] 2019 [cited 2020 Jun 4 ];7:172-176
Available from: http://www.amhsjournal.org/text.asp?2019/7/2/172/273045


Full Text



 Introduction



Dental agenesis is an important clinical and public health problem.[1],[2],[3],[4] Patients with missing permanent teeth may suffer from a reduced chewing ability, inarticulate pronunciation, and an unfavorable esthetic appearance.[5] This potentially affects their self-esteem, communication behavior, and professional performance.[6]

The reported incidences of tooth agenesis in orthodontic patients range from 2.3% to 15.7% in the permanent dentition excluding the third molars.[7] Tooth agenesis is commonly classified into three categories as follows: hypodontia, oligodontia, and anodontia.[8] Among them, oligodontia, a severe type of hypodontia, has been generally characterized as the absence of six or more permanent teeth excluding the third molars.[9],[10] The reported prevalence of oligodontia has ranged from 0.08% to 0.3%.[11],[12],[13],[14] The treatment of patients with dental agenesis represents an interdisciplinary challenge that includes specialists in oral surgery, operative dentistry, orthodontics, and prosthodontics. Management of missing teeth, especially lateral incisors, need to be closed or create space orthodontically for prosthesis.

A meta-analysis investigated the prevalence of nonsyndromic tooth agenesis; included 33 studies from North America, Australia, and Europe; and found a higher prevalence in Europe (5.5%) and Australia (6.3%) than in North America.[12] Most individuals were missing only one or two permanent teeth, with very few missing more than six. Mandibular second premolars and the maxillary lateral incisors were reported to be the most likely to be missing.[12],[15] Notably, the prevalence of tooth agenesis in the last few decades has reportedly increased.[16] However, there is no empirical evidence to support whether this apparent increase is due to more advanced screening and diagnosis or other factors.

The prevalence of tooth agenesis and the types of the most commonly missing teeth differed from one ethnic group to another.[17],[18],[19] Moreover, some studies revealed that tooth agenesis does not seem to affect the maxilla and the mandible differently,[12] while others found the mandible to be more frequently affected than the maxilla.[20]

To date, no such study has been carried out in Nepalese population. Hence, this study will be aimed to determine the prevalence and distribution of dental agenesis among orthodontic patients of Kathmandu, Nepal. Hence, the purpose of this study was to find out the prevalence of dental agenesis among Nepalese orthodontic patients of Kathmandu and its occurrence in relation to gender, location, and pattern of distribution in the maxillary and mandibular arches. This study was conducted to fill this lacuna, and it is hoped that these findings will be beneficial for future research.

 Materials and Methods



This cross-sectional descriptive study consisted of 601 participants (age range from 10 to 35 years) selected among the orthodontic patients who presented for orthodontic treatment in the Orthodontic Unit, Tribhuvan University Teaching Hospital and Dental Villa-Orthodontic Center and Speciality Dental Clinic, Kathmandu, Nepal. Sample size for this study was determined by using n = Z2pq/d2, where Z = 1.96, value of P is taken as 0.5, q = 1 − p = 0.5, allowable error (d) = 0.04 (96%), and n is the required sample size. Based on these parameters, the required sample size was 600.25. Hence, a total of 601 patients were selected from patients who presented for orthodontic treatment from 2016 to 2018.

Inclusion criteria of this study were patients between 10 and 35 years of age who presented for orthodontic treatment and gave consent to this study and presence of good-quality panoramic radiograph from a single source.

Patients were excluded who had previous orthodontic treatment, systemic disease, or craniofacial anomalies/congenital syndrome; missing teeth for decay processes; avulsions or extracted for orthodontics or other reasons. Ethical approval was obtained from the Institutional Review Committee of Institute of Medicine before conducting this study.

After obtaining the informed consent from the patients, demographic details along with detailed medical, dental, and family histories were obtained from the 601 patients (242 males and 359 females) aged between 10 and 35 years who require orthodontic treatment. In addition to the intraoral examination, dental panoramic radiograph obtained from a single source (Planmeca ProMax® 3D, Europe; exposure 66.0 kV, 8.0 mA, 15.8 s, 84.8 Gycm2) was evaluated for dental anomalies causing disturbance in number. The panoramic radiographs were analyzed by a trained observer after reliability testing who followed a preestablished protocol as follows: general observation of the teeth including the third molar, followed by a systematic analysis of the erupted and unerupted tooth number in each quadrant. A tooth was diagnosed as congenitally missing if the mineralization of its crown could not be identified on orthopantomogram.

The evaluation of digital orthopantamogram was carried out on a computer screen with a resolution of 1280 × 800 pixels. Data obtained from the panoramic radiographs were recorded by the same investigator according to gender, patient's age at the time of radiography, number of missing teeth and their location, maxillary versus mandibular agenesis, and right versus left side.

Statistical analysis

Data obtained were transferred to MS Excel sheet. The data were verified and analyzed statistically using SPSS Statistics Version 21.0 (IBM Corp. Armonk, NY, USA) with confidence level set at 95% (P< 0.05) to test for statistical significance. The prevalence of dental agenesis among orthodontic patients was descriptively analyzed. One hundred and twenty-five orthopantamograms were selected randomly after 2 weeks to assess the missing teeth for intraobserver reliability. Kappa coefficients were performed to assess the reliability (0.91). Pearson's Chi-square test was used at 5% significance level to investigate the significance of differences between gender, between right and left sides, and between maxillary and mandibular arches.

 Results



This study found that among the 601 participants, 242 (40.27%) were male, whereas 359 (59.73%) were female [Figure 1], and the mean age was 16.42 ± 3.428 years.{Figure 1}

The total number of missing teeth of the study sample according to the type of tooth and its location is summarized in [Table 1].{Table 1}

The prevalence of dental agenesis was 7.48% (45) excluding third molar and 27.62% (166) including third molar. The prevalence of oligodontia was 0.33% (2). The total number of missing teeth including the third molar was 371 (1.92%) and it was 72 (0.42%) while excluding the third molar [Table 2] and [Table 3].{Table 2}{Table 3}

There was no statistically significant difference in the prevalence of missing teeth in between gender (P = 0.996) [Table 2], in between right and left sides (P = 0.590) [Table 4], and in between upper and lower jaws (P = 0.010) [Table 5].{Table 4}{Table 5}

This study showed that among missing teeth (except the third molars), the maxillary lateral incisor was the most lost by 48.61% followed by mandibular lateral incisor (19.44%), mandibular central incisor (8.33%), mandibular second premolar (6.94%), and maxillary second premolar (5.55%). The canine, first premolar, maxillary central incisor, and second molar were rarely absent. There was no observation about the absence of the maxillary and mandibular first molars [Table 6].{Table 6}

 Discussion



The prevalence of dental agenesis was 7.48% excluding third molar for both sexes together. The prevalence of tooth agenesis, including third molars, was observed at 17.8% among females and 9.81% for males, at nearly 27.62% for both sexes together. The prevalence of oligodontia was 0.33%.

This research is the first of its kind in Nepal analyzing the prevalence of dental agenesis in a sample of orthodontic patients. According to literature review on the prevalence of agenesis, we could state that the range of prevalence values varies from 2.8% in the Malaysian population[21] to 12.6% in the German population.[22]

A higher prevalence rate was found in a few other studies: Chung et al. estimated a prevalence of 11.2% in Korean population[23] and 10.1% in Norway.[12] A very high prevalence was also reported in two German studies (12.6%[22] and 11.3%[24]). The wide range of prevalence values observed in these studies has indicated that geographic, gender, racial, and genetic differences as well as the huge differences in the sample size and criteria of selection play a fundamental role in the varied results of studies of hypodontia. This wide range could make the comparison of the result of this study very limiting with other previous studies.

This study showed that among missing teeth (except the third molars), the maxillary lateral incisor was the most lost by 48.61% followed by mandibular lateral incisor (19.44%), mandibular central incisor (8.33%), mandibular second premolar (6.94%), and maxillary second premolar (5.55%). The canine, first premolar, maxillary central incisor, and second molar were rarely absent. There was no observation about the absence of the maxillary and mandibular first molars.

In this study, there was no statistically significant difference in the prevalence of missing teeth in between gender (P = 0.996), in between right and left sides (P = 0.590), and in between upper and lower jaws (P = 0.010).

In addition to this, females presented a higher number of congenital missing teeth, which is in agreement with the majority of reports by Grahnén,[25] Haavikko,[26] Fekonja,[24] and Endo et al.[27] However, Larmour et al.[28] found that in the primary dentition, there was no gender distribution, whereas in the permanent dentition, females were affected more frequently than males at a ratio of 3:2. In the study of Behr et al. on the German population[22] and of Laganà et al. on a nonorthodontic Italian sample,[29] the percentage was equally distributed between males and females.

In the present study, of the individuals identified with congenitally missing teeth, 69% had one or two missing teeth; this is in accordance with other studies by Davis,[19] Fekonja,[24] Gomes et al.,[30] and Goya et al.[31] Thus, most of the affected individuals suffer only a mild form of hypodontia.

In this study, the most often congenital missing tooth type in patients observed in our study was maxillary lateral incisor. Polastri[32] and Abu Ain[33] had similar findings in studies on the Italian population, whereas Gracco et al.,[34] Lo Muzio et al.,[35] Laganà et al.,[29] and Sato et al.[36] found that the most affected tooth was the mandibular second premolars followed by maxillary lateral incisor.

Long-term multicentric collaborative studies in diverse population groups with greater sample size and inclusion of healthy control are suggested to make more comprehensive assessment of dental agenesis.

 Conclusion



Patients with missing teeth may suffer from unfavorable appearance, malocclusion, periodontal damage, insufficient alveolar bone growth, reduced chewing ability, inarticulate pronunciation, and other problems.

The most common missing teeth were maxillary lateral incisor followed by mandibular lateral incisor, mandibular central incisor, and mandibular second premolar while excluding third molars. There was no statistically significant difference in the prevalence of missing teeth in between gender, in between right and left sides, and in between upper and lower jaws.

Orthodontists have the responsibility to observe each patient carefully for dental agenesis and have full knowledge of them as it can help plan the best possible treatments, both esthetically and functionally by comprehensive multidisciplinary treatment.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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