Anomalies of tooth eruption and development in Iraqi 13 year olds : a national survey

الملخص EN

This study involved six governorates (cities and environs) in Iraq selected to cover the whole country geographically (Baghdad the capital, Ninevah, Basrah, Diyala, Anbar and Najaf).

The sample consisted of 6957 intermediate school students aged 13 years.

The clinical examination involved anomalies in the dentition (eruption, development and alignment) and the variables were mainly based on the definitions of Björk et al.

and the FDI.

One or more missing teeth due to extraction or trauma were found in 7.3% of the sample, and the most common extracted teeth were the first molars (3.1% mandibular and 1.3% maxillary).

Clinically judged hypodontia was found in 2.3 % of the sample.

One or more rotated teeth (≥15°) were found in 27.3 % of the sample, and the most common rotated tooth was the mandibular second premolar, then the mandibular and maxillary canines.

One or more displaced teeth (>1mm) were found in 26.1 % of the sample, and the most common displaced teeth were the maxillary canine buccally and the maxillary lateral incisor palatally.