Maturation of primary and permanent teeth in preterm infants

To elucidate the development of primary and permanent teeth and to interpret the effect of different calcium, phosphorus, and vitamin D supplementation in the neonatal period on dental maturation in preterm children.

Preterm infants were randomised to four groups to receive a vitamin D dose of 500 or 1000 IU/day and calcium and phosphorus supplemented or unsupplemented breast milk. The maturity of the primary and permanent teeth was recorded in 30 preterm children. Sixty children aged 2 years and 60 children aged 9-11 years served as controls. Bone mineral content/density was assessed in the preterm infants.

The median (range) corrected teething age was 7 (2-16) months in preterm infants and 6 (2-12) months in controls (p = 0.43). The median (range) number of erupted teeth at 2 years of age was 16 (11-19) in preterm infants and 16 (12-20) in controls (p = 0.16). Maturation of the permanent teeth in the preterm infants was not delayed compared with the controls (mean Demirjian SDS 0.16 v 0.49, p = 0.14). Early dietary intake of either mineral or vitamin D did not affect maturation of the primary dentition in preterm children. Children receiving the higher vitamin D dose in the neonatal period had more mature permanent dentition than those receiving the lower dose, but mineral intake did not affect maturation of the permanent teeth. Dental maturation did not correlate with bone mineral status.

This is the first longitudinal study to follow primary and permanent tooth maturation in the same preterm children. Premature birth has no appreciable late sequelae in tooth maturation.