Enamel defects were commoner in preterm children, and post-natal dietary intervention had no effect on their frequency. This is the first study in which enamel defects in both primary and permanent teeth have been studied in the same group of preterm children. At age 1 and 2 yrs, 32 preterm children were examined, and the same group was examined again at 9-11 yrs. As controls, 106 healthy children were examined at 1 and 2 yrs, and 64 of them were randomly selected for comparison. When the preterm children were aged 9-11 yrs, 64 of another group of 150 10-13 yr-olds were randomly chosen as controls. All were examined by the main author. At 2 yrs, 66% of preterm children had enamel hypoplasia, and 2% of controls (P < 0.001); enamel opacity affected respectively 13% and 19% (NS). However, the proportions of teeth thus affected were respectively 16% and 0.1%, and 13% and 4%. In the permanent dentition around 10 yrs later, 38% of preterm children had hypoplasia, and 11% of controls (P < 0.01), and opacity affected respectively 47% and 25% (P < 0.05). All preterm infants had primary dentition enamel defects, and 72% also had permanent dentition defects. The preterm infants had been randomly assigned to 2 levels of vitamin D supplementa-tion up to age 6 months, and to breast milk with or without a supplement of calcium and phosphorus until reaching a weight of 2kg. These supplements had no apparent effect on enamel defects.

Future research is needed about mothers' experiences using supplementation methods, test-weighing, exploring experiences of mothers of late-preterm infants, and the validity of the concept of coping with this phenomenon.

A combination of the criteria "serum total alkaline phosphatase activity above 900 IU/l" and "serum inorganic phosphate concentrations below 1.8 mmol/l" yielded a sensitivity of 100% at a specificity of 70%. This was the best available screening method for low bone mineral density in preterms.

A randomised double blind placebo controlled study was conducted to determine whether a one week course of dexamethasone could reduce the severity of bronchopulmonary dysplasia in preterm infants without compromising their adrenal function. Forty one infants with a mean birth weight of 880 g and a gestational age of 27 weeks who were ventilator dependent at 10 days of age were enrolled. At the age of 28 days pulmonary outcome was significantly better in the girls treated with dexamethasone but not in all infants. There was no difference between the groups in the long term outcome, except for a shorter duration of supplemental oxygen in dexamethasone treated female infants. After the one week dexamethasone treatment there was a significant but short lived suppression of the basal cortisol concentrations and the adrenal response to corticotrophin (ACTH). No serious side effects were observed.It is concluded that early one week dexamethasone treatment improves short term pulmonary outcome in premature infants, but there is no clear evidence of long term benefits.