Anomalies of Tooth Number in the Age Range of 2–5 Years in Nonsyndromic Children: A Literature Review

Aim and objective: Dental anomalies of number predispose the teeth to malocclusion, caries, periodontal problems, and often compromise aesthetics and function.We present a literature review to assess the distribution of these anomalies and observe associated anomalies of the underlying permanent successor teeth in the age range of 2-5 years in nonsyndromic children.Review: A literature search was conducted using the "PubMed" database with a manual search of cross-references, published in the years 2000-2018.The following key words were used: "dental anomalies, primary teeth" "hypodontia, " "oligodontia, " and "hyperdontia." Of the 1,232 records accessed, 41 articles were included in the final review-34 articles (42 clinical cases) and 7 cross-sectional studies.Results: The overall prevalence of dental anomalies of number ranged from 1.8 to 4.0%.Among all the clinical cases, a predilection for boys (26/42) was observed.Hyperdontia was the most common primary tooth number anomaly; 23.8% cases (10/42) had additional coexisting primary tooth anomalies.In 35.7% cases (15/42), anomalies of the permanent successor teeth were present of which permanent tooth agenesis was most commonly seen in 75% cases of hypodontia (3/4) and 85.7% cases of oligodontia (6/7).Conclusion: Among all the anomalies, hyperdontia was most common.The anomalies of tooth number were more prevalent in boys and in the maxilla.Apart from dental anomalies of number, those of shape and size also concurrently occurred in the primary dentition and in the permanent successor teeth, stressing upon early diagnosis, radiographic examination, and long-term follow-up visits.