Prevalence and change of malocclusions from primary to early permanent dentition: a longitudinal study.

OBJECTIVE To follow a group of children from primary to early permanent dentition and determine the prevalence, self-correction, and new development of malocclusions; the need for orthodontic treatment; and the possible influences of habits, breathing disturbances, and allergies. MATERIALS AND METHODS Two hundred and seventy-seven children were followed at 3, 7, and 11.5 years of age. Malocclusions and orthodontic treatment need were determined by clinical examinations. Data on sucking habits, breathing disturbances, allergies, dental trauma, and orthodontic treatments were collected from a questionnaire and dental records. RESULTS Malocclusions were found in 71% of participants at 3 years of age, 56% at 7 years of age, and 71% at 11.5 years of age. Self-correction was noted for anterior open bite, sagittal malocclusions, and posterior crossbite, while deep bite developed. A high number of contact point displacements and spacings contributed to the prevalence of malocclusion rate of 71% at 11.5 years. Severe or extreme orthodontic treatment need was apparent in 22%. Habits, allergies, or breathing disturbances found at 3 years of age had no associations with malocclusions at 11.5 years of age. CONCLUSIONS This sample revealed a significant percentage of malocclusions and orthodontic treatment need. A substantial number of self-corrections and establishment of new malocclusions occurred during the transition from primary to early permanent dentition.