GENOA ORAL GROWTH STUDY: Longitudinal Investigation of Preschool and Primary School Children

Once a year a clinical examination were performed. Data were collected with a questionnaire, that was filled out by the parents before the clinical examination, which included questions on child's clinical history, the type of feeding, the use of baby-bottle, the history of non-nutritive sucking habits (dummy-sucking and digit sucking) and the consent to the clinical examination. Two World Health Organization (WHO) calibrated examiners carried out the clinical examinations. They were blinded to the information collected from the parental questionnaires. Dental examinations were performed in a classroom environment under natural light, using gloves and masks in compliance with the infection control protocol, mouth mirrors and disposable paper rulers to measure overjet and overbite (in millimeters). The occlusion was assessed in centric occlusion and was classified according to Foster and Hamilton criteria [Foster and Hamilton, 1969] Radiographic examination was not performed.