Molar-incisor hypomineralization and oral hygiene in 10- to-12-yr-old Swedish children born preterm.

Although preterm birth is associated with an increased risk of medical problems and impairments, there is limited knowledge of how this affects oral health. It was hypothesized that when 10-12 yr of age, children who were preterm at birth would present with a higher prevalence of molar-incisor hypomineralization (MIH), more dental plaque, and a higher degree of gingival inflammation than full-term control children. Eighty-two preterm children, born between 24 and 32 wk of gestation, and 82 control children, born between 37 and 43 wk of gestation, were clinically examined for developmental defects in enamel, MIH, dental plaque, and gingival health. In addition, behaviour management problems were evaluated. Information on any aetiological factors with a potential influence on MIH and oral health was collected via questionnaires. Molar-incisor hypomineralization was more common in preterm children than in controls (38% vs. 16%), as were enamel developmental defects (69.5% vs. 51%). Low gestational age and low birth weight increased the risk of MIH. Preterm children had more plaque, a higher degree of gingival inflammation, and more behaviour-management problems than controls. In conclusion, oral health problems were more common in preterm children than in control children.