Related Experiment Video
Updated: Sep 23, 2026

Impact of Common Fruit Juices and Toothbrushing on the Discoloration of Primary Teeth
Published on: March 27, 2026
Traumatic injuries to permanent anterior teeth among 12-year-old schoolchildren in Jordan
Mahmoud A M Hamdan1, Lamis D Rajab
1Faculty of Dentistry, The University of Jordan, Amman. anwarm@ju.edu.jo
Objectives:
To assess the prevalence and related factors of incisor trauma among 12-year-old Jordanian schoolchildren.
Design:
Cross-sectional study among schoolchildren. A sample of 1.878 schoolchildren aged 12 years, 940 boys and 938 girls, were randomly selected from 128 schools in urban and rural areas. Ellis classification was used to record the dental injuries on incisors.
Results:
Of the children examined 13.8% showed dental trauma. Difference in prevalence between boys (17.1%) and girls (10.6%) was statistically significant (p < 0.05). Maxillary central incisors were the most affected (79.2%) and the most common type of crown injury was enamel-dentin fracture (40.6%). The relationship between dental injuries and socio-economic indicators was not statistically significant. There was a tendency for children with an incisal overjet greater than 5.0 mm to have experienced dental injuries (p < 0.01). Treatment need due to dental injuries was very high but less than untreated damage.
Conclusion:
The prevalence of traumatic injuries to permanent incisors in 12-year-old Jordanian schoolchildren was close to that found in other countries. Being a boy and having overjet greater than 5.0 mm were significant predisposing factors to dental injuries.
Related Concept Videos
Teeth
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin and...
Tooth Anatomy
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or grinding food.
