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Prevalence of Dental Anomalies in Norwegian School Children

Malformations of the teeth are designated as dental anomalies, including aberrant dimensions, numbers, morphology, and eruption patterns. Some studies have shown that dental anomalies can increase the risk of caries and periodontitis, and can lead to endodontic, aesthetic or orthodontic problems. For little studies about dental anomalies of children were examined in Norway, the authors of this paper conducted a study and aimed to examine the prevalence of dental anomalies in a population of Norwegian school children and investigate their possible association with gender and dental occlusion.

Diagnostic records: panoramic and periapical radiographs, dental casts and dental histories of 500 12-year-old school children (273 girls, 227 boys) were drawn from the growth files of the Department of Orthodontics, University of Oslo, Norway. The subjects were divided into three groups according to the Angle classification (Class Ι, n = 252. Class ΙΙ, n = 227. Class ΙΙΙ, n = 21). Data were evaluated and classified by one of the authors (LH) after calibration with an experienced orthodontist (VVR). And ten types of dental anomalies were diagnosed from dental cast and radiographic material: agenesis, taurodontism, pulp stones, microdontia, macrodontia, impaction, short roots, supernumerary teeth, ectopic eruption and tooth transposition. Percentages and chi-square test were used for evaluation of the data.

The results showed that in this population, 28.2% of the subjects showed at least one dental anomaly. And the most prevalent dental anomaly was impaction (8.4%), followed by agenesis (6.6%) and taurodontism (6.2%). Statistically significant associations were observed between agenesis and Angle Class II dental occlusion (P = 0.03), and between agenesis and gender (P = 0.004); none of the other dental anomalies showed significant differences between the different malocclusion groups or with gender.

All in all, agenesis was a predominant dental anomaly in girls and was found twice as often in subjects with Class ΙΙ than with Class Ι dental occlusion.

Article by Linn Haugland, et al, from Norway.

Full access: http://mrw.so/1VXCli

Image by ADRIAN J. VANDE MERWE, D.D.S., P.C., from Flickr-cc.

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