Places in the dental arch that show a greater variability in tooth number, shape and position—A prevalence study

Genetic and Morphological Variation in Hypodontia of Maxillary Lateral Incisors

(1) Background: Hypodontia has a multifactorial aetiology, in which genetic factors are a major component. Associated with this congenital absence, the formed teeth may show differences in size and shape, which may vary with the specific genetic variants and with the location of the missing teeth. The aims of the present study were to investigate a specific variant of MSX1, derive morphometric tooth measurements in a sample of patients with isolated maxillary lateral incisor agenesis and matched controls, and model the findings. (2) Methods: Genotyping of the MSX1 rs8670 genetic variant and morphometric measurements with a 2D image analysis method were performed for 26 hypodontia patients and 26 matched controls. (3) Results: The risk of upper lateral incisor agenesis was 6.9 times higher when the T allele was present. The morphometric parameters showed significant differences between hypodontia patients and controls and between the unilateral and bilateral agenesis cases. The most affected crown dimension in the hypodontia patients was the bucco-lingual dimension. In crown shape there was significant variation the Carabelli trait in upper first molars. (4) Conclusions: The MSX1 rs8670 variant was associated with variations in morphological outcomes. The new findings for compensatory interactions between the maxillary incisors indicate that epigenetic and environmental factors interact with this genetic variant. A single-level directional complex interactive network model incorporates the variations seen in this study.

Prevalence of Developmental Dental Anomalies of Number and Size in Indian Population According to Age and Gender

Introduction

Dental anomalies arise due to genetic and environmental factors in the morphodifferentiation stage of odontogenesis lead to alteration in the number and size of the tooth as well as the root.^1–3 The knowledge of their prevalence and the extent of involvement can provide valuable information for phylogenic and genetic studies and also help in the understanding of differences among the population and between various population groups.⁴ We aim to identify the prevalence and distribution of such anomalies according to age and gender. The acquired details of cases will further help the dental clinicians to understand their etiology which can further facilitate their diagnosis and effective management. Also, timely intervention can be achieved.

Materials and methods

Retrospective study of 4,000 subjects (equal proportion of males and female) of age range from 10 to 40 years were studied. Their radiographs, dental casts, and clinical findings were evaluated for number and size developmental dental anomaly.

Results

Incidence of overall 331 cases (8.27%) of number and size developmental dental anomalies were recorded with 173 (8.6%) males and 158 (7.9%) females. Hypodontia was the most frequently found dental anomaly in both males (4.9%) and females (4.4%) followed by hyperdontia and supernumerary roots. Microdontia was the most frequently found size anomaly in both males (1.6%) and females (1.9%).

Conclusion

Hypodontia (4.7%) is the most frequently found numeral anomaly in both males and females. Intergroup study shows a significant statistical difference in cases of hypodontia in the 10–25 years of age-group (6.2%) with a p value ≤ 0.00001.

How to cite this article

Jain A, Saxena A, Jain S, et al. Prevalence of Developmental Dental Anomalies of Number and Size in Indian Population According to Age and Gender. Int J Clin Pediatr Dent 2021;14(4):531–536.