Background: The aim of this national oral health survey was to determine the prevalence of malocclusions due to some anomalies in the dentition among the 13 years old Kurdish students in sulaimani intermediate school. Materials and methods: The total sample was 950 (455 males and 495 females) which assessed by diagnostic set and special instrument. The clinical examination was mainly based on the definitions of Björk et al. Some variables were recorded as present or absent sometimes denoting the tooth or the teeth involved in malocclusion and their distribution according to the whole sample. Results: The results showed that 1)The most common extracted tooth was the mandibular first molar (2.9%). 2) At this age group the most common partially erupted tooth was the maxillary canine (4.2%). 3) The most common unerupted tooth was the maxillary second molars. 4) The most common retained deciduous tooth was the maxillary canine (6.8%), then the maxillary second molars (5.4%).5) Hypodontia as judged clinically was found in 2.1% of the sample affecting one or more permanent teeth. The most common congenitally missing tooth was the maxillary lateral incisor (0.9%), mandibular second premolars (0.4%), and then maxillary second premolar (0.2%). 6) 29.2 % of the sample had one or more rotated teeth. The most common rotated tooth was the mandibular second premolars (5.3%). 7). The sample showed 30.4% with one or more displaced teeth. The most common displaced tooth was the maxillary lateral incisor (8.8%), then the maxillary canine (7.2%). Conclusion: At the age of 13 both males and females show large range of dental anomalies that are better to be controlled.
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