Fractured and avulsed permanent incisors in Finnish children. A retrospective study.

The frequency of traumatic injuries to permanent incisors was studied in a sample of 1614 children from the city of Lahti in Southern Finland. The children, 801 girls and 813 boys, ranged in age from 6 to 16 years. Injuries to hard dental tissues and exarticulations of teeth were recorded. The prevalence of injuries was 19.8%--14.6% in girls and 25.0% in boys. A rapid growth in the prevalence rates was found at the ages of 9--11 years, at which the estimated mean annual incidence was about 5% in girls and 7% in boys. In 78.4% of the children with injured incisors, one tooth only was injured. The teeth most commonly injured were the upper central incisors, 81.7%; and the most frequent type of injury was an uncomplicated crown fracture, 90.5%.